Patent Description:
<CIT> discloses a work vehicle operable by the operator with any of a battery and an external power. <CIT> describes an electric drive vehicle, system and method. The electric drive system comprises a motor capable of propelling the vehicle and an energy storage device coupled to the motor, and selectively coupled to a catenary line, wherein the catenary line is capable of supplying electrical power to the vehicle and to the energy storage device.

Vehicles are mobile machines that are designed and used for transporting passengers and/or cargos from one place to another. Examples of the vehicles may include bicycles, cars, trucks, locomotives, tractors, buses, boats, and aircrafts. Traditionally, at least some of these vehicles are powered by engines such as internal combustion engines. The internal combustion engines may operate by burning fuels such as diesels, gasoline, and natural gas for providing necessary power so as to drive motion of the vehicles. However, with rising concerns of scarcity, cost, and negative environmental impact in association with the use of the diesels, gasoline, and natural gas, growing interests have been raised to develop electric powered vehicles such as fully/pure electric vehicles, hybrid electric vehicles (e.g., integration of a battery and internal combustion engine), and plug-in hybrid electric vehicles. However, wide adoption of the electric powered vehicles is limited by a list of factors, one of which is that onboard or built-in energy storage device such as battery fails to meet the mileage requirement.

Therefore, it is desirable to provide improved apparatuses and methods to address one or more of the above-mentioned limitations.

In accordance with one example of the present disclosure, an apparatus is provided. The apparatus includes an onboard energy storage device, an onboard power conversion device, and at least one drive system. The onboard power conversion device is configured to be electrically coupled to an external power source for receiving electrical power therefrom. The at least one drive system is electrically coupled to the onboard energy storage device and the onboard power conversion device. The onboard energy storage device and the onboard power conversion device cooperatively provide electrical power for the at least one drive system.

In accordance with another aspect of the present disclosure, a vehicle is provided. The vehicle includes an onboard energy storage device for providing a first Direct Current (DC) power; an Alternating Current - Direct Current (AC-DC) converter configured to be electrically coupled to a utility power grid for receiving input Alternating Current (AC) power from the utility power grid and converting the input AC power to provide a second DC power; a DC bus electrically coupled to the onboard energy storage device and the AC-DC converter for receiving the first DC power and the second DC power respectively; a traction inverter electrically coupled to the DC bus for converting at least one of the first DC power and the second DC power received at the DC bus to traction AC power; and a traction motor electrically coupled to the traction inverter, the traction motor configured to convert the traction AC power received from the traction inverter to mechanical power to drive movement of the vehicle, wherein the AC-DC converter continues receiving the input AC power from the utility power grid to maintain the movement of the vehicle.

In accordance with yet another aspect of the present disclosure, a method of managing power supply of an apparatus is provided. The method includes: receiving input alternating current (AC) power from a utility power grid; converting the received input AC power to provide a first DC power; and converting at least part of the first DC power to at least one of a traction AC power and a power take-off (PTO) AC power, respectively, for a traction motor and a PTO motor of the apparatus; wherein receiving input AC power from a utility power grid is implemented concurrently with converting at least part of the first DC power to at least one of a traction AC power and a PTO AC power.

In accordance with yet another aspect of the present disclosure, a computer-readable storage medium is provided. The computer-readable storage medium has a plurality of instructions stored thereon. The plurality of instructions can be executed by one or more processors to achieve the following: receiving input alternating current (AC) power from a utility power grid; converting the received input AC power to provide a first DC power; and converting at least part of the first DC power to at least one of a traction AC power and a power take-off (PTO) AC power, respectively, for a traction motor and a PTO motor of the apparatus; wherein receiving input AC power from a utility power grid is implemented concurrently with converting at least part of the first DC power to at least one of a traction AC power and a PTO AC power.

Embodiments disclosed herein generally relate to improved power supply mechanisms for vehicles and method for managing the power supply thereof. More specifically, the present disclosure proposes a new hybrid electrical power supply mechanism, dual electrical power supply mechanism, or electric-electric hybrid power supply mechanism for vehicles. As used herein, the term "hybrid electrical power supply mechanism," "dual electrical power supply mechanism," or "electric-electric hybrid power supply mechanism" refers to a power supply mechanism that, at least in some modes of operation, a vehicle can be operated with electrical power cooperatively provided from a first electrical power arrangement and a second electric power arrangement. In some specific implementations, the first electrical power arrangement may comprise an onboard or built-in electrical power source (e.g., onboard energy storage device such as a battery or battery pack) capable of storing electrical power therein and providing electrical power for maintaining the operation of the vehicle. The second electrical power arrangement may comprise an onboard or built-in power interface or power conversion device integrated with the vehicle. The onboard or built-in power interface or power conversion device is capable of being coupled to an external power source and converting the electrical power received from an external power source (e.g., a utility power grid) to a suitable form for use by the vehicle (e.g., charging the onboard energy storage device or driving at least one drive system in association with the vehicle). As such, when the external power source is available to the vehicle, the proposed hybrid electrical power supply mechanism can be implemented to cooperatively provide electrical power to maintain operations of the vehicle; while when the external power source is unavailable, the vehicle can be powered by the onboard energy storage device.

In some implementations, based on the proposed hybrid electrical power supply mechanism, dual electrical power supply mechanism, or electric-electric hybrid power supply mechanism, the vehicle can be arranged or programmed to operate in a plurality of modes. One of the operation modes is separate operation control which refers to the first electrical power arrangement and the second electrical power arrangement are operating separately for supplying electrical power to the vehicle. More particularly, for the separate operation control, when the second electrical power arrangement is available, the first electrical power arrangement is disabled and the second electrical power arrangement is responsible for supplying electrical power to maintain the operation of the vehicle; while when the second electrical power arrangement is not available, the first electrical power arrangement is enabled to supply electrical power to maintain the operation of the vehicle. Another operation mode of the vehicle is series hybrid operation control which refers to the first electrical power arrangement and the second electrical power arrangement simultaneously supply electrical power to at least one drive system of the vehicle. Yet another operation mode of the vehicle is combined charging and operation control which refers to the second electrical power arrangement can be configured to simultaneously supply electrical power to the first electrical power arrangement (e.g., charging a battery or battery pack) and at least one drive system in association with the vehicle. A wide range of vehicles can benefit from the hybrid electrical power supply mechanism as well as the various modes of operation proposed herein. Non-limiting examples of the vehicles may include land vehicles that drive against ground, such as bicycles, motorcycles, cars, trucks, vans, buses, tractors, off-way vehicles, agricultural tractors, E-buses, golf cars, industrial construction machines, trailers, locomotives, trains, and subways, to name just a few. The vehicles may also include water vehicles or marine vessels, such as ships, boats, and the like, to name just a few. Furthermore, the vehicles may include air vehicles such as aircrafts, planes, and the like.

The present disclosure can achieve various technical effects or technical advantages, one of which is that the mileage of the vehicle can be extended in at least some modes of operation. For example, in the series hybrid operation control mode, the onboard power source such as an onboard battery can be charged during the drive system is being supplied with electrical power from the onboard power interface. In some embodiments, a conventional internal combustion engine (ICE) may be removed from the vehicle of the present disclosure. Implementing the vehicle without the use of ICEs may not only contribute to a reduction of tailpipe pollutants, but also help to reduce or eliminate noise emissions. Other technical effects or technical advantages will become apparent to those skilled in the art by referring to the detailed descriptions provided herein and the accompanying drawings.

In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the one or more specific embodiments.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," and the like, as used herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Also, the terms "a" and "an" do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. The term "or" is meant to be inclusive and mean either any, several, or all of the listed items. The use of "including," "comprising," or "having" and variations thereof herein are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms "connected" and "coupled" are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect. The terms "circuit," "circuitry," and "controller" may include either a single component or a plurality of components, which are either active and/or passive components and may be optionally connected or otherwise coupled together to provide the described function.

Turning now to the drawings, first referring to <FIG>, in which there is shown an overall block diagram of a vehicle <NUM> in accordance with one exemplary embodiment of the present invention. In general, the vehicle <NUM> is adapted to implement the above-mentioned hybrid electrical power supply mechanism in a manner that at least two sources of electrical power are cooperatively provided to maintain the operation of the vehicle <NUM>. As shown in <FIG>, the vehicle <NUM> includes at least one first power source or an onboard power source <NUM> which is configured to supply a first form of electrical power or internally-supplied electrical power <NUM> with suitable voltage and/or power to facilitate driving motion of the vehicle <NUM> and/or to facilitate performing some specific tasks in association with the vehicle <NUM>. Depending on the specific types of vehicle <NUM>, the specific tasks performed by the vehicle <NUM> may include mowing plants, plowing ground, lifting materials, shoveling materials, excavating materials, and dumping materials, and so on. According to the invention, the onboard power source <NUM> is an onboard energy storage device such as a battery or battery pack consisting of multiple battery cells coupled together in series and/or parallel configuration. Non-limiting examples of the battery or battery pack may include lead acid batteries, nickel cadmium batteries (NiCd), nickel metal hydride batteries (NiMH), lithium ion batteries, lithium polymer batteries, and so on. In some embodiments, the battery-type onboard energy storage device <NUM> may be physically replaced with a new fully charged one, if the battery power is depleted. Also, a person skilled in the art will recognize that a variety of energy storage components, such as ultra-capacitor, fly-wheel, and any other components capable of storing electrical energy can be additionally or alternatively used in association with the vehicle <NUM>.

With continued reference to <FIG>, the vehicle <NUM> also includes an onboard power interface <NUM> which functions as a power interface between various components of the vehicle <NUM> and an external power source <NUM>. The onboard power interface <NUM> is configured to provide a second source of electrical power to maintain operation of the vehicle <NUM>. In one embodiment, the onboard power interface <NUM> is electrically coupled to the external power source <NUM> via an electrical link <NUM>. In one embodiment, the electrical link <NUM> between the external power source <NUM> and the onboard power interface <NUM> may be one or more electric wires or electric cables. In other embodiments, the electrical link <NUM> may be wireless electrical power transfer link. In some specific embodiments, the electrical link <NUM> between the onboard power interface <NUM> and the external power source <NUM> is arranged to be flexible. For example, in some applications, an electrical wire of the electrical link <NUM> is arranged to have sufficient length to allow the onboard power interface <NUM> to continue receiving electrical power while the drive system <NUM> is operating to drive motion of the vehicle <NUM> or perform one or more specific tasks in association with the vehicle <NUM>. According to the invention, the onboard power interface <NUM> is an onboard power conversion device which is configured to perform power conversion with respect to the electrical power received from the external power source <NUM> and provide converted electrical power with suitable voltage and/or power to various components of the vehicle <NUM>. Depending on the various operation modes of the vehicle <NUM> which will be described in more detail below, the electrical power provided from the onboard power interface <NUM> can be delivered to charge the onboard energy storage source <NUM>, or delivered to a drive system <NUM> for driving motion of the vehicle <NUM> or performing one or more specific tasks (e.g., mowing grass, plowing ground, lifting materials, shoveling materials, excavating materials, and dumping materials) in association with the vehicle <NUM>.

With continued reference to <FIG>, the vehicle <NUM> may further include a first switch <NUM>. The first switch <NUM> is electrically coupled to the onboard power source <NUM> and a bus structure <NUM>. The bus structure <NUM> may be any suitable arrangements such as DC bus for facilitating unidirectional or bidirectional energy transfer between various components of the vehicle <NUM>. For example, the bus structure <NUM> may receive input such as DC electrical power provided from the onboard power interface <NUM>. The bus structure <NUM> may also provide output such as at least a part of the DC electrical power to charge the onboard power source <NUM>. The first switch <NUM> can be any type of mechanical and/or electrical devices or combinations thereof. The first switch <NUM> can be closed to establish or form a power/energy transfer link between the onboard power source <NUM> and the bus structure <NUM>, such that charging and/or discharging of the onboard power source <NUM> can be realized. As used herein, "closed" may refer to an "ON" status of a switch that low impedance is created by operating the switch. The first switch <NUM> can also be opened to terminate or cut off the power/energy transfer link between the onboard power source <NUM> and the bus structure <NUM>, such that the onboard power source <NUM> may not be able to supply electrical power to other vehicle components or the onboard power source <NUM> can be protected from over-charging or over-discharging problems. As used herein, "opened" may refer to an "OFF" status of a switch that high impedance is created by operating the switch. In one embodiment, the opening and closing of the first switch <NUM> can be manually performed by an operator or a user such as a driver according to real-time operating conditions and/or requirements of the vehicle <NUM>. In other embodiments, the first switch <NUM> can be automatically switched according to on/off signals which may be generated by monitoring various operating conditions and/or statuses of the vehicle <NUM>.

With continued reference to <FIG>, the vehicle <NUM> further includes a second switch <NUM>. The second switch <NUM> is electrically coupled to the bus structure <NUM> and a drive system <NUM>. The second switch <NUM> can be any type of mechanical and/or electrical devices or combinations thereof. Similar to the first switch <NUM> discussed above, the second switch <NUM> can also be manually switched or automatically switched to establish or terminate a power/energy transfer link between the bus structure <NUM> and the drive system <NUM>, such that unidirectional or bidirectional power transfer between the bus structure <NUM> and the drive system <NUM> can be enabled or disabled. In one embodiment, as shown in <FIG>, the drive system <NUM> may include a converter <NUM> and a motor <NUM>. The converter <NUM> is one type of a power conversion device functioning to convert one form of electrical power to another. For example, the converter <NUM> may be a DC-AC power conversion device configured to convert DC power received from a DC bus of the bus structure <NUM> to AC power. The AC power (e.g., three-phase AC power) is supplied to the motor <NUM> (e.g., three-phase AC motor) such that the motor <NUM> can be operated to provide a mechanical output such as torque output to drive the vehicle <NUM> to move. In other embodiments, the motor <NUM> can also provide mechanical outputs for one or more implements or tools designed to perform specific tasks.

With continued reference to <FIG>, the vehicle <NUM> is configured or programmed to provide a plurality of modes of operation. Switching between the operation modes of the vehicle <NUM> may be implemented according to instructions/commands input from an operator or a user such as a driver. In some alternative embodiments, it is possible that in an unmanned vehicle <NUM>, switching or transition between the operation modes can be automatically performed according to operation conditions and/or statuses of the vehicle <NUM>.

In a first aspect, the vehicle <NUM> may be configured to provide a first operation mode of separate control. In the separate control operation mode, the vehicle <NUM> can be further configured to operate in different states depending on for example whether the external power source <NUM> is available for supplying electrical power to the vehicle <NUM>.

In a first condition, the external power source <NUM> may be unavailable to the vehicle <NUM>, that is, the onboard power interface <NUM> is electrically decoupled with the external power source <NUM>. In this condition, upon determining that the onboard power source <NUM> has sufficient remaining power stored therein, the onboard power source <NUM> can be operated to provide electrical power to various components of the vehicle <NUM>, which may be referred to as battery powered mode. In one embodiment, to enable the power transfer, the first switch <NUM> and the second switch <NUM> are closed or turned on to allow the electrical power obtained from a battery or battery pack of the onboard power source <NUM> to be transferred to the bus structure <NUM>. In one embodiment, the converter <NUM> receives electrical power at the bus structure <NUM> and converts the electrical power to a suitable form of the motor <NUM> to operate. As a result, the motor <NUM> can provide necessary mechanical outputs for driving motion of the vehicle <NUM> or performing specific tasks in association with the vehicle <NUM>.

In a second condition, the external power source <NUM> is available to the vehicle <NUM> and the onboard power interface <NUM> can be electrically coupled to the external power source <NUM> to receive electrical power therefrom. The onboard power interface <NUM> can provide electrical power to various components of the vehicle <NUM>, which may be referred to as plugin mode. In the plugin mode, when the onboard power source <NUM> such as a battery or battery pack is determined to have insufficient remaining power, the first switch <NUM> can be closed or turned on and the second switch <NUM> can be opened or turned off. That is, the power transfer link between the bus structure <NUM> and the drive system <NUM> is cut off to disable the operation of the drive system <NUM>, while the power transfer link between the bus structure <NUM> and the onboard power source <NUM> is established to allow electrical power to be delivered through the power transfer link to charge the battery or battery pack of the onboard power source <NUM>. Still in the plugin mode, when it is determined that the onboard power source <NUM> has sufficient remaining power, the onboard power interface <NUM> can provide electrical power to other components of the vehicle <NUM>. For example, the first switch <NUM> can be opened and the second switch <NUM> can be closed. That is, the power transfer link between the onboard power source <NUM> and the bus structure <NUM> is cut off to make the onboard power source <NUM> standby, while the power transfer link between the bus structure <NUM> and the drive system <NUM> is established to allow the electrical power obtained from the onboard power interface <NUM> to be transferred to the drive system <NUM>. Consequently, the drive system <NUM> can provide mechanical outputs for driving motion of the vehicle <NUM> or performing specific tasks in association with the vehicle <NUM>.

In a second aspect, the vehicle <NUM> may be configured to provide a second operation mode of series hybrid control. In the series hybrid control mode, upon determining that the external power source <NUM> is available, the onboard power interface <NUM> can be electrically coupled to the external power source <NUM> to receive electrical power therefrom and provide converted electrical power to the bus structure <NUM>. If the onboard power source <NUM> such as a battery or battery pack is determined to have insufficient remaining power (e.g., a SOC of the battery or battery pack is below than a first threshold value, e.g., <NUM>%), the first switch <NUM> is closed and the second switch <NUM> is opened. That is, the energy transfer link between the onboard power source <NUM> and the bus structure <NUM> is established to allow electrical power to be delivered through the energy transfer link for charging the battery or battery pack of the onboard power source <NUM>. The energy transfer link between the bus structure <NUM> and the drive system <NUM> is cut off to disable the operation of the drive system <NUM>. Still in the series hybrid control mode, if the onboard power source <NUM> such as a battery or battery pack is determined to have sufficient remaining power (e.g., a SOC of the battery or battery pack is above a second threshold value, e.g., <NUM>%), both the first switch <NUM> and the second switch <NUM> are closed or turned on. In this case, the onboard power source <NUM> and the onboard power interface <NUM> can be paralleled to provide electrical power to the drive system <NUM>, as such, the drive system <NUM> can be operated to drive motion of the vehicle <NUM> and/or perform specific tasks in association with the vehicle <NUM>. In some embodiments, the amount of the electrical power provided from the onboard power source <NUM> and the amount of the electrical power provided from the onboard power interface <NUM> can be determined according to some predetermined distribution rules. For example, in one embodiment, the onboard power interface <NUM> is controlled to provide average power for the drive system <NUM>, while the onboard power source <NUM> is controlled to provide dynamic power for the drive system <NUM>. That is, when a traction motor of the drive system <NUM> requires large mechanical torque to accelerate the vehicle <NUM> or an implement or tool of the vehicle <NUM> requires large torque to perform special tasks, the onboard power source <NUM> can be configured to provide peak power to meet this requirement. When the traction motor of the drive system <NUM> doesn't require large mechanical torque or the implement or tool of the vehicle <NUM> is operating with light load, the onboard power source <NUM> can reduce its electrical power output. In a specific embodiment, the onboard power interface <NUM> may be controlled to operate at a constant output voltage mode, thus design of the onboard power interface <NUM> can be simplified.

In a third aspect, the vehicle <NUM> may be configured to provide a third operation mode of combined charging and operation control. In the combined charging and operation control mode, charging of the onboard power source <NUM> and driving of the drive system <NUM> can be performed concurrently or simultaneously. More specifically, when the external power source <NUM> is available, the onboard power interface <NUM> can be electrically coupled to the external power source <NUM> to receive the electrical power therefrom and convert the received electrical power to a suitable form for the bus structure <NUM>. In one embodiment, both the first switch <NUM> and the second switch <NUM> can be closed or turned on. That is, a first energy transfer link between the onboard power source <NUM> and the bus structure <NUM> can be established to allow at least a part of the electrical power at the bus structure <NUM> to be delivered through the first energy transfer link for charging a battery or a battery pack of the onboard power source <NUM>. Also, a second energy transfer link between the bus structure <NUM> and the drive system <NUM> can be established to allow at least part of the electrical power at the bus structure <NUM> to be delivered through the second energy transfer link for driving motion of the vehicle <NUM> and/or performing one or more specific tasks in association with the vehicle <NUM>. In a specific embodiment, the onboard power interface <NUM> is controlled to operate at a constant current mode. In one embodiment, in the constant current mode, a current reference for charging a battery or battery back of the onboard power source <NUM> can be determined based at least in part on a desired power of the drive system <NUM> and a desired charging power of the onboard power source <NUM>. Still in the combined charging and operation control mode, when it is determined that a battery or battery pack of the onboard power source <NUM> is charged to have sufficient remaining power (e.g., a SOC of the battery or battery exceeding ahigh-SOC threshold value, e.g., <NUM>%), the onboard power interface <NUM> and the onboard power source <NUM> can be paralleled to provide electrical power to the drive system <NUM>, as such, the drive system <NUM> can drive motion of the vehicle <NUM> and/or perform one or more specific tasks in association with the vehicle <NUM>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance another exemplary embodiment of the present invention. As shown in <FIG>, the vehicle <NUM> includes an onboard energy storage device <NUM> which may be a battery or battery back with suitable current and/or power output. The onboard energy storage device <NUM> is electrically coupled to an ES switch <NUM> which can be switched on and off according to switching signals <NUM> transmitted from a vehicle controller <NUM>. In alternative embodiments, the ES switch <NUM> can be manually switched on and off by an operator. The vehicle <NUM> further includes an onboard power conversion device <NUM> which may be electrically coupled to a utility power grid <NUM>. In one embodiment, when the utility power grid <NUM> is available for supplying electrical power, the utility power grid <NUM> may provide AC electrical power <NUM> (e.g., 220V or 380V electrical power depending on local grid standard) to the onboard power conversion device <NUM>. In one embodiment, the onboard power conversion device <NUM> may include an AC-to-DC conversion device (e.g., rectifier) which is configured for converting the AC electrical power <NUM> according to control signals <NUM> transmitted from the vehicle controller <NUM> and provide DC electrical power with suitable voltage and/or power. The DC electrical power is supplied to a DC bus <NUM> for further delivery to various components of the vehicle <NUM>.

With continued reference to <FIG>, the vehicle <NUM> further include a drive system <NUM> which can be supplied with electrical power from the onboard energy storage device <NUM> and/or the onboard power conversion device <NUM>. According to the invention, the drive system <NUM> includes a traction drive system or TM branch as indicated by reference numeral <NUM> in <FIG>. The traction drive system or the TM branch <NUM> is arranged for providing necessary mechanical output for driving motion of the vehicle <NUM>. In one embodiment, the TM branch <NUM> includes a TM switch <NUM>, a TM bus <NUM>, a TM converter <NUM>, and a traction motor <NUM>. The TM switch <NUM> is electrically coupled between the DC bus <NUM> and the TM bus <NUM>. In one embodiment, the TM switch <NUM> can be opened or closed according to switching signals <NUM> transmitted from the vehicle controller <NUM>, such that energy/power transfer link between the DC bus <NUM> and the TM branch <NUM> can be established or terminated. The energy flow between the DC bus <NUM> and the TM branch <NUM> can be unidirectional or bidirectional.

The TM converter <NUM> is electrically coupled between the TM bus <NUM> and the traction motor <NUM>. The TM converter <NUM> is configured to perform power conversion by converting DC electrical power received from the TM bus <NUM> to an output power <NUM> with suitable form for use by the traction motor <NUM>. In one embodiment, the TM converter <NUM> may comprise an inverter such as a DC-AC inverter which is capable of converting the DC electrical power at the TM bus <NUM> to AC electrical power <NUM> (e.g., three-phase AC electrical power). The AC electrical power <NUM> can be regulated by a vehicle controller <NUM>. For example, in one embodiment, in response to a traction torque command signal generated by operating an input device such as an acceleration pedal, the vehicle controller <NUM> can send control signals <NUM> to the TM converter <NUM> to cause the TM converter <NUM> to provide regulated AC electrical power <NUM> for the traction motor <NUM>. As such, the traction motor <NUM> (e.g., AC electric motor) can operate according to the AC electrical power <NUM> to provide desired torque output for driving motion of the vehicle <NUM>. In other embodiments, the traction motor <NUM> may include a DC motor and correspondingly the TM converter <NUM> may comprise a DC-DC converter to perform DC power conversion. The vehicle controller <NUM> may include any suitable programmable circuits or devices such as a digital signal processor (DSP), a field programmable gate array (FPGA), a programmable logic controller (PLC), and an application specific integrated circuit (ASIC).

With continued reference to <FIG>, the drive system <NUM> further includes a power take-off (PTO) drive system or a PTO branch as indicated by reference numeral <NUM> in <FIG>. For purpose of illustration and description, only a single PTO branch <NUM> is shown and described herein, however, a person having ordinary skill in the art will recognize that in some alternative embodiments, the drive system <NUM> may include a plurality of PTO branches which may be configured in parallel with each other. The PTO drive system or the PTO branch <NUM> is arranged for providing necessary mechanical power output for example torque output, for performing one or more specific tasks in association with the vehicle <NUM>. Examples of the specific tasks may include mowing plants, plowing grounds, lifting materials, shoveling materials, excavating materials, and dumping materials. According to the invention, the PTO drive system or the PTO branch <NUM> includes a PTO switch <NUM>, and may include a PTO bus <NUM>, a PTO converter <NUM>, and a PTO motor <NUM>. The PTO switch <NUM> is electrically coupled between the DC bus <NUM> and the PTO bus <NUM>. The PTO switch <NUM> can be switched on or off according to PTO switching signals <NUM> transmitted from the vehicle controller <NUM>, such that an energy/power transfer link between the DC bus <NUM> and the PTO branch <NUM> can be established or terminated. The energy flow between the DC bus <NUM> and the PTO branch <NUM> can be unidirectional and bidirectional.

The PTO converter <NUM> is electrically coupled between the TM bus <NUM> and the PTO motor <NUM>. The PTO converter <NUM> is configured to perform power conversion by converting DC electrical power received at PTO bus <NUM> to a PTO output <NUM> having a suitable form for use by the PTO motor <NUM>. In one embodiment, the PTO converter <NUM> may comprise a PTO DC-AC converter or PTO inverter which is capable of converting DC electrical power received at the PTO bus <NUM> to AC electrical power <NUM> (e.g., three-phase AC electrical power). Also, the AC electrical power <NUM> can be regulated by the vehicle controller <NUM>. For example, in one embodiment, in response to a PTO torque command signal generated by operating an input device installed with the vehicle <NUM>, the vehicle controller <NUM> can send control signals <NUM> to the PTO converter <NUM> to cause the PTO converter <NUM> to provide regulated AC electrical power <NUM> for the PTO motor <NUM>. As such, the PTO motor <NUM> can operate according to the AC electrical power <NUM> to provide desired torque output for performing one or more specific tasks in association with the vehicle <NUM>. In other embodiments, the PTO motor <NUM> may include a DC motor and correspondingly the PTO converter <NUM> may comprise a DC-DC converter to perform DC power conversion. In some applications, for example, in a forklift apparatus, the PTO motor <NUM> may be associated with one or more hydraulic pump systems for performing the tasks of lifting and transporting materials/cargoes.

The vehicle <NUM> shown in <FIG> can be configured or programmed to operate with a plurality of modes, such as separate control mode, series hybrid control mode, and combined charging and operation mode. Detailed description of these operations mode will be described later with reference to flow chart diagram of <FIG>. Before describing the flow chart diagrams, various structural embodiments of the vehicle are described with reference to <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with another exemplary embodiment of the present disclosure. The overall structure of the vehicle <NUM> and the operation thereof is substantially similar to the vehicle <NUM> that has been described with reference to <FIG>. One of the differences of the vehicle <NUM> shown in <FIG> is that the onboard power conversion device <NUM> is electrically coupled to a portable electricity generator <NUM>. The portable electricity generator <NUM> may run on diesel fuel, gasoline, or other suitable material. When the portable electricity generator <NUM> is available, the onboard power conversion device <NUM> can be electrically coupled to the portable electricity generator <NUM> and receive the electrical power <NUM> (e.g., AC electrical power) from the portable electricity generator <NUM> and convert the received electrical power <NUM> to suitable form for use by various components of the vehicle <NUM>. In one embodiment, the onboard power conversion system <NUM> may comprise an AC-DC conversion device which is capable of converting AC electrical power <NUM> to DC electrical power supplied to a DC bus <NUM>. The electrical power output from the onboard power conversion device <NUM> can be regulated according to control signals <NUM> transmitted from the vehicle controller <NUM>. The vehicle <NUM> shown in <FIG> can also be configured to operate with a plurality of modes, such as separation control mode, series hybrid control mode, and combined charging and operation control mode, which will be described in more detail below with reference to the flow chart diagrams of <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with another exemplary embodiment of the present disclosure. The overall structure of the vehicle <NUM> shown in <FIG> and the operations thereof is substantially similar to the vehicle <NUM> shown and described with reference to <FIG>. One of the differences of the vehicle <NUM> shown in <FIG> is that an onboard power conversion device <NUM> is electrically coupled to a solar panel device <NUM>. The solar panel device <NUM> is one type of a renewable power generation device which is designed for converting solar or light irradiation energy into electrical energy for direct consumption by household or transmission and distribution by a power grid. In some embodiments, the solar panel device <NUM> is arranged as a standalone device which is located separate with respect to the vehicle <NUM>. In some other embodiments, the solar panel device <NUM> may be integrated with the vehicle <NUM>. As such, when the solar panel device <NUM> is available to provide electrical power converted from solar irradiation, the onboard power conversion device <NUM> can be configured to receive electrical power <NUM> provided from the solar panel device <NUM> and convert the electrical power <NUM> to an electrical power with suitable voltage and/or power for delivering to various components of the vehicle <NUM>. In one embodiment, the onboard power conversion device <NUM> may include a DC-DC converter which is configured to perform DC-DC power conversion to provide DC electrical power with suitable voltage and/or power. Also, the DC electrical power provided from the DC-DC converter <NUM> can be regulated according to control signals <NUM> transmitted from the vehicle controller <NUM>. The vehicle <NUM> shown in <FIG> can also be configured to operate with a plurality of modes, such as separation control mode, series hybrid control mode, and combined charging and operation control mode, which will be described in more detail below with reference to the flow chart diagrams of <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with another exemplary embodiment of the present disclosure. The overall structure of the vehicle <NUM> shown in <FIG> and the operations thereof are substantially similar to the vehicle <NUM> shown and described with reference to <FIG>. One of the differences of the vehicle <NUM> shown in <FIG> is that the onboard power conversion device <NUM> can be electrically coupled to a wind turbine generator <NUM>. A wind turbine generator <NUM> is another form of renewable power generation device that is designed for converting kinetic energy of wind into electrical energy for grid transmission and/or distribution. In some embodiments, multiple wind turbine generators <NUM> may be grouped together as a wind farm for providing greater power output. In one embodiment, one or more wind turbine generators <NUM> may be integrated with the vehicle <NUM>. In other embodiments, one or more wind turbine generators <NUM> may be separately arranged with respect to the vehicle <NUM>. In one embodiment, when the wind turbine generator <NUM> is available to provide electrical power converted from wind energy, the onboard power conversion device <NUM> can be electrically coupled to the wind turbine generator <NUM> and receive the electrical power <NUM> therefrom. In one embodiment, the electrical power <NUM> provided from the wind turbine generator <NUM> may be AC power with suitable voltage and/or power. Correspondingly, the onboard power conversion device <NUM> may comprise an AC-DC converter functioning to convert the AC electrical power <NUM> to DC power with suitable voltage and/or power to be supplied to the DC bus <NUM>. In other embodiments, additionally or alternatively, the wind turbine generator <NUM> may be configured to provide DC power with suitable voltage and/or power <NUM>. Correspondingly, the onboard power conversion device <NUM> may additionally or alternatively comprise a DC-DC converter <NUM> functioning to convert first DC power <NUM> to second DC power with suitable voltage and/or power to be supplied to the DC bus <NUM>. The output of the onboard power conversion device <NUM> can be regulated or adjusted according to control signals <NUM> transmitted from the vehicle controller <NUM>. The vehicle <NUM> shown in <FIG> can also be configured to operate with a plurality of modes, such as separation control mode, series hybrid control mode, and combined charging and operation control mode, which will be described in more detail below with reference to the flow chart diagrams of <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with another exemplary embodiment of the present disclosure. The overall structure and detailed operations of the vehicle <NUM> show in <FIG> is substantially similar to what has been described above with reference to <FIG>. One difference of the vehicle <NUM> shown in <FIG> is that the vehicle <NUM> may be configured to be electrically coupled to a hydro-micro turbine generator <NUM>. The hydro-micro turbine generator <NUM> is yet another form of renewable power generation device which is functioning to convert water wave energy into electrical power. In one embodiment, the hydro-micro turbine generator <NUM> may be integrated with the vehicle <NUM>. In other embodiments, the hydro-micro turbine generator <NUM> may be arranged as a standalone device, that is, located remotely with respect to the vehicle <NUM>. As shown in <FIG>, the vehicle <NUM> is provided with an onboard power conversion device <NUM> (e.g., a AC-DC converter or a DC-DC converter) for converting electrical power <NUM> provided from the hydro-micro turbine generator <NUM> to DC power with suitable voltage and/or power to be supplied to the DC bus <NUM>. In some embodiments, the DC power output from the onboard power conversion device <NUM> can be regulated according to control signals <NUM> transmitted from the vehicle controller <NUM>. The vehicle <NUM> shown in <FIG> can also be configured to operate with a plurality of modes, such as separation control mode, series hybrid control mode, and combined charging and operation control mode, which will be described in more detail below with reference to the flow chart diagrams of <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with another exemplary embodiment of the present disclosure. The overall structure and detailed operations of the vehicle <NUM> is substantially similar to what has been described above with reference to <FIG>. One difference of the vehicle <NUM> shown in <FIG> is that a converter <NUM> is provided in association with the onboard energy storage device <NUM>. In the illustrated embodiment, the converter <NUM> is illustrated being electrically coupled between the ES switch <NUM> and the DC bus <NUM>. In other embodiments, the converter <NUM> can also be electrically coupled between the onboard energy storage device <NUM> and the ES switch <NUM>. In one embodiment, the converter <NUM> may comprise a DC-DC converter which is configured to convert first DC power <NUM> provided from the onboard energy storage device <NUM> to second DC power <NUM> with suitable voltage and/or power to be supplied to the DC bus <NUM>. In one embodiment, the DC-DC converter <NUM> may comprise a unidirectional DC-DC converter for performing DC power conversion, such as boosting the voltage of the first DC power <NUM> to match the voltage at the DC bus <NUM>. In other embodiments, the DC-DC converter <NUM> may comprise a bidirectional DC-DC converter which may be useful for collecting power during regenerative or braking operations of the vehicle <NUM>. For example, when the vehicle <NUM> is operating in a regenerative mode, the bidirectional DC-DC converter <NUM> can be operated to convert at least a part of the DC power at the DC bus <NUM> to DC power for charging the onboard energy storage device <NUM>. In the regenerative mode, at least part of the DC power at the DC bus <NUM> can be provided from the TM branch <NUM> by operating the traction motor <NUM> as a generator, which converts motion energy of the vehicle <NUM> into electrical power. The DC power at the DC bus <NUM> can also be provided from the PTO branch <NUM>. For example, when vehicle <NUM> is a forklift, the PTO motor <NUM> can be operated as a generator which converts gravitational potential energy of a load into electrical power. As shown in <FIG>, the converter <NUM> can be operated according to control signals <NUM> transmitted from the vehicle controller <NUM> to provide desired DC power for the DC bus <NUM> or desired DC power for the onboard energy storage device <NUM>.

With continued reference to <FIG>, in the illustrated embodiment, the onboard power conversion device <NUM> is electrically coupled to an external power source <NUM> for receiving electrical power <NUM> provided therefrom. The external power source <NUM> can be any one of the power sources described above with reference to <FIG>. When the external power source <NUM> is available, electrical power obtained from the external power source <NUM> can be provided to the TM branch <NUM> and/or the PTO branch <NUM> in coordination with the onboard energy storage device <NUM>. The vehicle <NUM> shown in <FIG> can also be configured to operate with a plurality of modes, such as separation control mode, series hybrid control mode, and combined charging and operation control mode, which will be described in more detail below with reference to the flow chart diagrams of <FIG>.

<FIG> illustrates a detailed block diagram of a vehicle <NUM> in accordance with yet another exemplary embodiment of the present disclosure. The overall structure and operations thereof are substantially similar to what has been described above with reference to <FIG>. For example, the vehicle <NUM> can optionally include a unidirectional or bidirectional DC-DC converter <NUM> electrically coupled between the onboard energy storage device <NUM> and the DC bus <NUM>. In addition, the vehicle <NUM> may be further provided with an onboard energy storage protection function. More specifically, the vehicle <NUM> may include a sensor <NUM> which is electrically coupled to the output of the onboard energy storage device <NUM> for detecting one or more electrical parameters in association with the onboard energy storage device <NUM>. In one embodiment, as shown in <FIG>, a current detector is used as the sensor <NUM> for detecting charging and/or discharging current in association with the operation of the onboard energy storage device <NUM>. In other embodiments, other sensors or transducers may be used, including but not limited to, voltage sensors and/or thermal sensors. In response the current detection, the current detector <NUM> may transmit a current feedback signal <NUM> representing actual or practical current flowing into or flowing from the onboard energy storage device <NUM> to the vehicle controller <NUM>. The vehicle controller <NUM> may derive a charging and/or discharging status of the onboard energy storage device <NUM> based at least in part on the current feedback signal <NUM>. In one embodiment, when a state of charge (SOC) of a battery or a battery pack of the onboard energy storage device <NUM> is determined to be fully charged (e.g., a SOC value exceeding a preset value), the vehicle controller <NUM> may transmit a switching signal <NUM> to the ES switch <NUM> to open the ES switch <NUM> (i.e., OFF state) to stop charging the onboard energy storage device <NUM>. In another situation, when the SOC of a battery of a battery pack of the onboard energy storage device <NUM> is determined to be overly discharged (e.g., a SOC value being smaller than a preset value), the vehicle controller <NUM> may similarly transmit a switching signal <NUM> to the ES switch <NUM> to stop discharging the onboard energy storage device <NUM>.

It should be noted that the various embodiments of the vehicles <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> shown and described above are merely examples only to help explain the general principles of the present disclosure. In some embodiments, two or more of the vehicles described above can be combined in some manner. For example, in some embodiments, the vehicle <NUM> shown in <FIG> can also be configured to have an onboard power conversion device <NUM> that is capable of receiving electrical power both from the utility power grid <NUM> and the solar panel device <NUM> shown in <FIG>. Thus, as long as one of the utility power grid <NUM> and the solar panel device <NUM> is available, the vehicle <NUM> can be operated with electrical power concurrently provided from the external power source (either the utility power grid <NUM> or the solar panel device) and the onboard energy storage device <NUM>. Similarly, in some other embodiments, the vehicle <NUM> shown in <FIG> can be configured to have an onboard power conversion device <NUM> that is capable of receiving electrical power both from the solar panel device <NUM> and the wind turbine generator <NUM> shown in <FIG>.

<FIG> illustrate flowchart diagrams of methods <NUM>, <NUM>, and <NUM> for operating a vehicle and/or managing power supply of a vehicle in accordance with exemplary embodiments of the present disclosure. The methods <NUM>, <NUM>, and <NUM> described herein can be implemented with at least some of the vehicles <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> shown in <FIG>. For purpose of simplifying description of these methods, the one or more blocks of methods <NUM>, <NUM>, and <NUM> will be specifically described as being tied to one or more components of the vehicle <NUM> shown in <FIG>, however, the implementation of these method blocks should not be limited to the one or more components. Also, it should be noted that at least a part of blocks of these methods <NUM>, <NUM>, and <NUM> shown in <FIG> may be programmed with software instructions stored in a computer-readable storage medium which, when executed by a processor, perform various blocks of the methods <NUM>, <NUM>, and <NUM>. The computer-readable storage medium may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology. The computer-readable storage medium includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium which can be used to store the desired information and which can accessed by a processor.

Turning now to <FIG>, the method <NUM> generally provides a separate control operation mode for the vehicle <NUM> to implement. One benefit of providing such a separate control operation mode for the vehicle <NUM> is that the design of the control system of the vehicle <NUM> can be simplified. In one embodiment, the method <NUM> may start to implement from block <NUM>. At block <NUM>, an electrical connection or coupling for interconnecting the vehicle with an external power source is established. The electrical connection may be established by plugging one or more electrical wires or cables to an electric outlet in association with the external power source <NUM>. In other embodiments, it is possible to establish a wireless connection between the external power source <NUM> and the vehicle <NUM> for wireless electrical power transfer. In one embodiment, the vehicle <NUM> is particularly equipped with an onboard power interface such as an onboard power conversion device <NUM> (e.g., AC-DC converter) for converting the electrical power <NUM> (e.g., AC electrical power) received from the external power source <NUM> to a suitable form (e.g., DC electrical power) for various components of the vehicle <NUM>.

At block <NUM>, the method <NUM> continues to implement by determining whether a charging mode of the vehicle is enabled. More specifically, the determining at block <NUM> can be made by the vehicle controller <NUM> to ascertain whether a battery or a battery pack of the onboard energy storage device <NUM> has sufficient remaining power. If the determining by the vehicle controller <NUM> reveals that the onboard energy storage device <NUM> has low remaining power, that is, the vehicle <NUM> should be charged, the method <NUM> then proceeds to block <NUM> to implement. On the other hand, if the determining by the vehicle controller <NUM> reveals that a battery or a battery pack of the onboard energy storage device <NUM> has sufficient remaining power, that is, the vehicle <NUM> doesn't need to be charged, the method <NUM> may proceed to block <NUM> to implement, which will be described later.

At block <NUM>, following the affirmative determination at block <NUM> that the vehicle should be operating in the charging mode, all the drive system of the vehicle is disabled. More specifically, in one embodiment, a traction drive system or a traction branch <NUM> shown in <FIG> for driving motion of the vehicle <NUM> is disabled. In another embodiment, additionally, a PTO drive system or a PTO branch <NUM> shown in <FIG> for performing one or more specific tasks in association with the vehicle <NUM> is disabled. In a particular embodiment, a TM switch <NUM> in the TM branch <NUM> and/or a TPO switch <NUM> in the PTO branch <NUM> can be opened or turned off by switching signals <NUM>, <NUM> transmitted from the vehicle controller <NUM>. In other embodiments, the TM switch <NUM> and the PTO switch <NUM> can be opened or turned off in a manual manner.

At block <NUM>, further following the affirmative determination at block <NUM> that the vehicle should be operating in the charging mode, the method <NUM> may continue to implement by establishing an energy transfer link between the external power source and the onboard energy storage device. In one embodiment, the establishment of the energy transfer link can be achieved by closing or turning on the ES switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>. In alternative embodiments, the ES switch <NUM> can also be closed or turned on by manual operation of an operator or a user such as a driver.

At block <NUM>, the method <NUM> continues to implement by transferring at least a part of the electrical energy from the external power source to the onboard energy storage device. In one embodiment, the electrical power provided from the external power source <NUM> is first converted by the onboard power conversion device <NUM> such as an AC-DC converter to DC electrical power. The DC electrical power then is delivered through the DC bus <NUM> and the ES switch <NUM> to the onboard energy storage device <NUM>, such that the onboard energy storage device can be charged. Various charging strategies may be employed for charging the onboard energy storage device <NUM>. For example, the onboard energy storage device may be charged with a constant current or a constant voltage or a combination thereof.

At block <NUM>, following the negative determination made at block <NUM> that the vehicle is not operating in the charging mode, the method <NUM> may continue to determine whether the vehicle should be operating in a driving mode. The determining may be made by the vehicle controller <NUM> to ascertain whether one or more command signals for driving the vehicle <NUM> has been received. If the determining by the vehicle controller <NUM> reveals that one or more command signals has been received, that is the vehicle <NUM> should be operating in the driving mode, the method <NUM> may proceed to block <NUM> to implement, which will be described later. On the other hand, if the determining by the vehicle controller <NUM> reveals that there aren't any command signals received by the vehicle <NUM>, that is, the vehicle <NUM> is not operating in the driving mode, the method <NUM> may return back to block <NUM> for further determining whether the vehicle <NUM> should be operating in charging mode.

At block <NUM>, following the affirmative determination that the vehicle is operating in the driving mode, the method <NUM> may continue to implement by disabling the onboard energy storage device of the vehicle. In one embodiment, the ES switch <NUM> is turned off or opened according to switching signal <NUM> transmitted from the vehicle controller <NUM>, such that the energy transfer link between the DC bus <NUM> and the onboard energy storage device <NUM> is cut off, thereby, the onboard energy storage device <NUM> stops charging and/or discharging.

At block <NUM>, following the affirmative determination that the vehicle is operating in the driving mode, the method <NUM> may continue to implement by establishing at least one energy transfer link between the external power source and at least one drive system of the vehicle. In one embodiment, an energy transfer link is established between the external power source <NUM> and a traction drive system or a TM branch <NUM>. More specifically, a TM switch <NUM> is turned on or closed by a switching signal <NUM> transmitted from a vehicle controller <NUM>. In another embodiment, the TM switch <NUM> may be turned on or closed by manual operation. In another embodiment, additionally or alternatively, another energy transfer link is established between the external power source <NUM> and a PTO drive system or a PTO branch <NUM> shown in <FIG>. More specifically, the establishment of the another energy transfer link may be achieved by turning on or closing the PTO switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>. In alternative embodiment, the PTO switch <NUM> may be turned on or closed by manual operation.

At block <NUM>, with the at least one established energy transfer link, electrical power is transferred from the external power source to the at least one drive system. In one embodiment, the electrical power provided from the external power source is first converted to a suitable form (e.g., DC power) for the DC bus <NUM> by the onboard power interface or the onboard power conversion device <NUM> (e.g., AC-DC converter). Then, the DC electrical power on the DC bus <NUM> is delivered through the established energy transfer link to the TM branch <NUM> for driving motion of the vehicle <NUM>. In another embodiment, the DC electrical power on the DC bus <NUM> can be delivered through the another established energy transfer link to the PTO branch <NUM> for performing one or more specific tasks in association with the vehicle <NUM>.

As long as the electrical power from the external power source <NUM> is available, the onboard power interface or the onboard power conversion device <NUM> continues supplying electrical power to the DC bus <NUM> to maintain the movement of the vehicle <NUM> or to maintain the one or more specific tasks implementation in association with the vehicle <NUM>. The benefit of using externally-supplied electrical power for driving motion of the vehicle <NUM> or performing one or more special task in association with vehicle <NUM> is that the power stored in the battery or battery pack of the onboard energy storage device <NUM> can be reserved for extending the overall mileage of the vehicle <NUM>. For example, in one embodiment, the vehicle <NUM> may be embodied as an electric tractor. When an external power source such as a utility power grid <NUM> is available, the electric tractor <NUM> can be operated with the electrical power <NUM> provided from the utility power grid <NUM> without consuming the energy stored in the battery or battery pack of the onboard energy storage device <NUM>. After some tasks such as plowing grounds have been performed, and the external power source such as the utility power grid <NUM> is unavailable for supplying electrical power to maintain the driving of the vehicle <NUM>, the vehicle <NUM> can quickly switch to an internal power supply mode and use electrical power obtained from the onboard energy storage device <NUM> to maintain the operation of the vehicle <NUM>.

Referring to <FIG>, the method <NUM> generally provides a series hybrid control operation mode for the vehicle <NUM> to implement or operate with. The method <NUM> contains similar blocks as those have been described with reference to <FIG>. For example, the method <NUM> contains a block <NUM> similar to block <NUM> for establishing an electrical connection between the vehicle and an external power source.

At block <NUM>, the method <NUM> continues to implement by determining whether an onboard energy storage device has a low remaining power. In one embodiment, the determining may be made by a vehicle controller <NUM> to ascertain whether a state of charge (SOC) of an battery or battery pack of the onboard energy storage device <NUM> is equal to or below a first threshold value (may also be referred to as a low-SOC threshold value). If the determining by the vehicle controller <NUM> reveals that the SOC of the onboard energy storage device is equal to or below the first threshold value, that is, the onboard energy storage device <NUM> has low remaining power, the method <NUM> may proceed to block <NUM> to implement, which will be described in more detail later. On the other hand, if the determining by the vehicle controller <NUM> reveals that the SOC of the onboard energy storage device <NUM> is not equal to or below the first threshold value, the method <NUM> may proceed to block <NUM> to implement, which will be described in more detail later.

At block <NUM>, all the drive system of the vehicle is disabled. In one embodiment, a traction drive system or a traction branch <NUM> shown in <FIG> for driving motion of the vehicle <NUM> is disabled. In another embodiment, additionally, a PTO drive system or a PTO branch <NUM> shown in <FIG> for performing one or more specific tasks in association with the vehicle <NUM> is disabled. In a particular embodiment, a TM switch <NUM> in the TM branch <NUM> and/or a TPO switch <NUM> in the PTO branch <NUM> can be opened or turned off by switching signals <NUM>, <NUM> transmitted from the vehicle controller <NUM>. In other embodiments, the TM switch <NUM> and the PTO switch <NUM> can be opened or turned off in a manual manner.

At block <NUM>, following the affirmative determination that the onboard energy storage device has low remaining power, the method <NUM> continues to implement by establishing an energy transfer link between the external power source and the onboard energy storage device. With the established energy transfer link, the method <NUM> may move to block <NUM> to implement, where at least a part of the electrical energy provided from the external power source is delivered to the onboard energy storage device so as to charge the energy storage device. Blocks <NUM>, <NUM> are substantially similar to the blocks <NUM> and <NUM> that have been shown and described with reference to <FIG>, thus, detailed descriptions of the two blocks <NUM>, <NUM> are omitted here.

At block <NUM>, the method <NUM> continues to implement by determining whether an onboard energy storage device of the vehicle has sufficient remaining power. In one embodiment, the determining at block <NUM> may be made by the vehicle controller <NUM> to ascertain whether the SOC of a battery or a battery pack of the onboard energy storage device <NUM> is equal to or above a second threshold value (may also be referred to as high-SOC threshold value). If the determination made by the vehicle controller <NUM> reveals that the SOC of the battery or battery pack of the onboard energy storage device <NUM> is equal to or above the second threshold value or the high-SOC threshold value, that is, the onboard energy storage device <NUM> has sufficient remaining power, the method <NUM> may proceed to the block <NUM> to implement, which will be described in more detail later. On the other hand, if the determining made by the vehicle controller <NUM> reveals that the SOC of the battery or battery pack of the onboard energy storage device <NUM> is not equal to or above the second threshold value or the high-SOC threshold value, the method <NUM> may proceed to block <NUM> to implement, which will be described in more detail later.

At block <NUM>, the method <NUM> continues to implement by providing a combination electrical power from the onboard energy storage device and the external power source to at least one drive system. Implementation of the block <NUM> may involve a plurality of sub-blocks. <FIG> illustrates a more detailed flowchart diagram of the block <NUM> in accordance with one exemplary embodiment.

Referring to <FIG>, at sub-block <NUM>, an energy transfer link between the onboard energy storage device and a DC bus is established. In one embodiment, the establishment of the energy transfer link may be achieved by turning on or closing the ES switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>. At sub-block <NUM>, with the established energy transfer link, electrical power is transferred from the onboard energy storage device <NUM> to the DC bus <NUM>.

Sub-block <NUM> may be implemented concurrently with the sub-block <NUM>. At sub-block <NUM>, at least part of electrical power is transferred from the external power source to the DC bus. In one embodiment, as shown in <FIG>, an onboard power conversion device <NUM> is utilized for converting electrical power provided from the external power source <NUM> to DC electrical power, which in turn is supplied to the DC bus <NUM>.

At sub-block <NUM>, the electrical power transferred from the onboard energy storage device and the external power source are combined. In one embodiment, the electrical power provided from the onboard energy storage device <NUM> and the electrical power provided from the onboard power interface or the onboard power conversion device <NUM> is combined at the DC bus <NUM>.

At sub-block <NUM>, at least one electrical connection between the DC bus and a drive system is established. In one embodiment, a first energy transfer link between the DC bus <NUM> and the TM branch <NUM> is established. The establishment of the first energy transfer link may be achieved by transmitting a switching signal <NUM> from the vehicle controller <NUM> to a TM switch <NUM>, so that the TM switch <NUM> can be turned on or closed according to the switching signal <NUM>. In another embodiment, a second energy transfer link between the DC bus <NUM> and the PTO branch <NUM> can be established. The establishment of the second energy transfer link can be achieved by turning on or closing the PTO switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>.

At sub-block <NUM>, the process continues to implement by transferring electrical power through the established energy transfer link. In one embodiment, when the first energy link between the DC bus <NUM> and the TM branch <NUM> is established, DC electrical power at the DC bus <NUM> can be provided to TM inverter <NUM> in the TM branch <NUM>. The TM inverter <NUM> converts the received DC electrical power to AC electrical power <NUM> which is used by the traction motor <NUM> to provide mechanical output such as torque output for driving motion of the vehicle <NUM>. In another embodiment, when the second energy transfer link between the DC bus <NUM> and the PTO branch <NUM> in established, DC electrical power at the DC bus <NUM> can be transferred to the PTO inverter <NUM> in the PTO branch <NUM>. The PTO inverter <NUM> converts the received DC electrical power to AC electrical power <NUM> which is used by the PTO motor to provide mechanical outputs such as torques outputs to perform one or more specific tasks in association with the vehicle <NUM>.

Referring now to <FIG>, the method <NUM> generally provides a combined charging and operation control mode for the vehicle <NUM> to implement or operate with. The method <NUM> contains similar blocks as those have been described with reference to <FIG>. For example, the method <NUM> contains a block <NUM> which is similar to blocks <NUM>, <NUM> described above for establishing an electrical connection between the vehicle and an external power source.

At block <NUM>, following the established electrical connection between the vehicle and the external power source, electrical power from the external power source can be concurrently provided to the onboard energy storage device and at least a drive system of the vehicle. In one embodiment, concurrently providing electrical power from the external power source to the onboard energy storage device and at least one drive system may involve a plurality of actions to be performed. <FIG> illustrates various actions that may be involved in block <NUM> in accordance with one exemplary embodiment of the present disclosure.

Referring to <FIG>, at sub-block <NUM>, electrical power obtained from the external power source is converted into a suitable form. In one embodiment, as shown in <FIG>, the onboard power conversion device <NUM> converts the electrical power (e.g., AC electrical power from a utility power grid) into DC electrical power for supply to the DC bus <NUM>. In some specific embodiments, the power conversion device <NUM> can be controlled to operate at a constant output current mode. In the constant output current mode, the onboard power conversion device <NUM> supplies the DC electrical power with a constant current to the DC bus <NUM>. In one embodiment, a desired constant current value can be determined based at least in part on the power that the traction motor <NUM> and/or the PTO motor <NUM> desired to provide as well as the power that the battery or batter pack of the onboard energy storage device <NUM> is desired to be charged with. After the desired current reference is determined, a command signals representing the desired current reference can be input to the vehicle controller <NUM>, which in turn transmits control signals <NUM> to cause the onboard power conversion device <NUM> to provide the desired reference current output.

Further referring to <FIG>, after sub-block <NUM>, the process is basically split into two parallel branches <NUM> and <NUM>. In the first branch <NUM>, at sub-block <NUM>, an energy transfer link between the onboard energy storage device and a DC bus is established. In one embodiment, as shown in <FIG>, the establishment of the energy transfer link between the onboard energy storage device <NUM> and the DC bus <NUM> can be achieved by turning on or closing the ES switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>. In alternative embodiment, the ES switch <NUM> may be turned on or closed manually. At sub-block <NUM>, with the established energy transfer link between the DC bus <NUM> and the onboard energy storage device <NUM>, a first part of electrical power at the DC bus <NUM> is transferred from the DC bus <NUM> to the onboard energy storage device <NUM>.

Further referring to <FIG>, at sub-block <NUM> in the second branch <NUM>, an energy transfer link between the DC bus and at least one drive system is established. In one embodiment, a first energy transfer link between the DC bus <NUM> and the TM drive system or the TM branch <NUM> is established. More specifically, the establishment of the first energy transfer link between the DC bus <NUM> and the TM branch <NUM> can be established by turning on or closing the TM switch <NUM> according to the switching signal <NUM> transmitted from the vehicle controller <NUM>. Alternatively, the TM switch <NUM> can also be turned on or closed manually. In another embodiment, a second energy transfer link between the DC bus <NUM> and the PTO drive system or the PTO branch <NUM> is established. More specifically, the establishment of the second energy transfer link can be achieved by turning on or closing the PTO switch <NUM> according to switching signal <NUM> transmitted from the vehicle controller <NUM>. Alternatively, the PTO switch <NUM> can also be turned on or closed manually.

At sub-block <NUM> of the second branch <NUM>, electrical power at the DC bus can be delivered through the established energy transfer link to the at least one drive system. In one embodiment, at least a second part of DC electrical power at the DC bus <NUM> can be delivered through the first energy transfer link to the TM inverter <NUM> in the first branch <NUM>. The TM inverter <NUM> converts the DC electrical power to AC electrical power for driving the traction motor <NUM> to provide mechanical output such as torque output to drive motion of the vehicle <NUM>. In another embodiment, at least a second part of DC electrical power at the DC bus <NUM> can be delivered through the second energy transfer link to the PTO converter <NUM> in the second branch <NUM>. The PTO converter <NUM> converts DC electrical power to AC electrical power for driving the PTO motor <NUM> to provide mechanical output such as torque outputs to perform one or more specific tasks in association with the vehicle <NUM>.

Referring back to <FIG>, at block <NUM>, the method <NUM> continues to determine whether an onboard energy storage device is fully charged. The purpose of this block <NUM> is to ensure a battery or a battery pack of the onboard energy storage device will not be over-charged, because the battery lifetime can be significantly reduced when the battery or battery pack of the onboard energy storage device is over-charged. In one embodiment, as shown in <FIG>, a sensor <NUM> such as a current detector is used for detecting a charging current in association with the battery or battery pack of the onboard energy storage device <NUM>. The charging current feedback detected with the current detector <NUM> can be supplied to the vehicle controller <NUM> for calculating or deducing a charging energy or a charging status of the battery or battery pack of the onboard energy storage device. Thus, determination can be made to ascertain whether the battery or battery pack of the onboard energy storage device is fully charged by comparing the calculated charging energy or charging status with a predefined value. If the determination reveals that the onboard energy storage device is fully charged, the method <NUM> may proceed to block <NUM> or alternatively to block <NUM> to implement, which will be described in more detail later. If the determination reveals that the onboard energy storage device is not fully charged, the method <NUM> may proceed to block <NUM>, which will be described in more detail later.

At block <NUM>, following the determination at block <NUM> that the onboard energy storage device has been fully charged, the onboard energy storage device may be disconnected from the external power source. In one embodiment, the ES switch <NUM> is turned off or opened according to switching signal <NUM> transmitted from the vehicle controller <NUM>, such that the energy transfer link between the DC bus <NUM> and the onboard energy storage device <NUM> is cut off. In alternative embodiment, the ES switch <NUM> can be turned off or opened manually for cutting off the energy transfer link. As shown with phantom line in <FIG>, the block <NUM> may be omitted in some implementations. In this case, the method <NUM> may proceed to block <NUM>, particularly, electrical power from the external power source and the onboard energy storage device are combined. In one embodiment, the combined electrical power may be transferred to at least one drive system such as the TM branch <NUM> and PTO branch <NUM> shown in <FIG>. The operations involve in block <NUM> is substantially similar to the block <NUM> shown and described above with reference to <FIG>, thus, detailed descriptions of the block <NUM> is omitted herein.

At block <NUM>, following the negative determination that the onboard energy storage device is not fully charged, the method <NUM> continues to determine whether the onboard energy storage device is over-discharged. In one embodiment, the current detector <NUM> as shown in <FIG> can also be used to detect the direction of the current flowing through the energy transfer link between the onboard energy storage device <NUM> and the DC bus <NUM>. More specifically, when the current is detected being flowing from the onboard energy storage device <NUM> to the DC bus <NUM>, it represents that the onboard energy storage device <NUM> is discharging. Further, the current feedback signals <NUM> can be transmitted to the vehicle controller <NUM> to further calculate or deduce a discharging status of the onboard energy storage device <NUM>. Thus, determination can be made to ascertain whether the onboard energy storage device is over-discharged by comparing the discharging status with a predefined value. If the determination reveals that the onboard energy storage device has been over-discharged, the method <NUM> may proceed to block <NUM> to implement, which will be described in more detail later. If the determination reveals that the onboard energy storage device hasn't been over-discharged, the method <NUM> may return back to block <NUM> for concurrently providing electrical power from the external power source to the onboard energy storage device and at least one drive system. In an alternative embodiment, following the negative determination at block <NUM>, the method <NUM> may return back to block <NUM> to implement, to combine the electrical power from the onboard energy storage device and the external power source.

At block <NUM>, following the affirmative determination at block <NUM> that the onboard energy storage device is over-discharged, the method <NUM> continues to implement to disconnect the onboard energy storage device with the at least one drive system. It is also beneficial to detect whether a battery or battery pack of the onboard energy storage device is over-discharging, because an over-discharged battery or battery pack also has a reduced battery lifetime. In one embodiment, the disconnection is achieved by turning off or opening the ES switch <NUM> according to the switching signal <NUM> transmitted from the vehicle controller <NUM>, such that the energy transfer link between the DC bus <NUM> and the onboard energy storage device <NUM> is cut off, thereby, the onboard energy storage device <NUM> cannot supply electrical power to the TM branch <NUM> and the PTO branch <NUM>. Alternatively, the ES switch <NUM> can be turned off or opened in a manual manner.

At block <NUM>, the method <NUM> continues to implement by providing electrical power from the external power source to at least one drive system. For example, as shown in <FIG>, the electrical power from the external power source <NUM> can be converted by the onboard power conversion device <NUM> to DC electrical power for supply to the DC bus <NUM>. In one embodiment, by turning on the TM switch <NUM>, the electrical power at the DC bus <NUM> can be supplied to the TM branch <NUM> for driving motion of the vehicle <NUM>. In another embodiment, by turning on the PTO switch <NUM>, the electrical power at the DC bus <NUM> can be supplied to the PTO branch <NUM> for performing one or more tasks in association with the vehicle <NUM>.

Although the embodiments discussed herein relate to the use with vehicles, it will be appreciated that the teachings of the present disclosure may be used with other applications, such as elevators or escalators.

Claim 1:
A vehicle, comprising:
an onboard energy storage device (<NUM>);
an onboard power conversion device (<NUM>) configured to be electrically coupled to an external power source (<NUM>) for receiving electrical power therefrom; a
at least one drive system (<NUM>) electrically coupled to the onboard energy storage device (<NUM>) and the onboard power conversion device (<NUM>), wherein the at least one drive system (<NUM>) comprises a traction drive system and a power take-off, PTO, drive system, the traction drive system is configured to receive electrical power cooperatively provided from the onboard energy storage device (<NUM>) and the onboard power conversion device (<NUM>) for driving movement of the vehicle; and the PTO drive system is configured to receive electrical power cooperatively provided from the onboard energy storage device (<NUM>) and the onboard power conversion device (<NUM>) for driving movement of at least one implement in association with the PTO drive system;
a DC bus (<NUM>) coupled to the onboard energy storage device (<NUM>) and the onboard power conversion device (<NUM>);
characterized in further comprising
a traction switch (<NUM>) electrically coupled to the DC bus (<NUM>) and the traction drive system; and
a PTO switch (<NUM>) electrically coupled to the DC bus (<NUM>) and the PTO drive system;
wherein when the vehicle is operating in a charging mode, the traction switch (<NUM>) is opened to disable the traction drive system; and wherein when the vehicle is operating in a driving mode, the traction switch (<NUM>) is closed to allow at least a part of the electrical power provided from the onboard power conversion device (<NUM>) to be transferred to the traction drive system via the DC bus (<NUM>) and the traction switch (<NUM>); and
wherein when the vehicle is operating in a charging mode, the PTO switch (<NUM>) is opened to disable the PTO drive system; and wherein when the vehicle is operating in a driving mode, the PTO switch (<NUM>) is closed to allow at least a part of the electrical power provided from the onboard power conversion device (<NUM>) to be transferred to the PTO drive system via the DC bus (<NUM>) and the PTO switch (<NUM>).