Patent Description:
Modern structures, such as office buildings and residences, utilize heating, ventilation, and air conditioning (HVAC) systems having controllers that allow users to control the environmental conditions within these structures. These controllers have evolved over time from simple temperature based controllers to more advanced programmable controllers, which allow users to program a schedule of temperature set points in one or more environmental control zones for a fixed number of time periods as well as to control the humidity in the control zones, or other similar conditions. Typically, these HVAC systems use an air handler that includes a motor and a fan to deliver the conditioned air to an interior space.

These motors commonly utilize an integrated or external variable frequency drive (VFD) to drive a permanent magnet motor. However, since the VFD traditionally remains connected to an AC input source, a constant standby power consumption is typically present, even when the blower motor is not running. This results in increased energy cost and carbon consumption. Accordingly, there remains a need to a solution to reduce energy consumption during standby (i.e., when the blower motor is not running).

<CIT> discloses a method for soft start of a motor in a heating, ventilation, and cooling (HVAC) system, including operably connecting a first switching device with the motor.

According to a first aspect of the invention, a heating, ventilation, and air conditioning (HVAC) system is provided. The HVAC system including: a blower assembly including a blower motor; and an electronically commutated motor (ECM) controller in electrical communication with the blower motor, the ECM controller including: a rectifier electrically connected to an alternating current (AC) input source, the rectifier being configured to receive AC electricity from the AC input source and convert the AC electricity from the AC input source to direct current (DC) electricity; a DC electrical circuit including a first DC electrical circuit loop and a second DC electrical circuit loop, the rectifier being configured to circulate the DC electricity through the DC electrical circuit; and a relay located within the first DC electrical circuit loop, the relay being configured to open to break the first DC electrical circuit loop and close to complete the first DC electrical circuit loop in order to reduce standby power consumption of the ECM controller.

The HVAC system includes: a DC-to-DC converter electrically connected to the rectifier, the DC-to-DC converter being configured to receive the DC electricity at a first voltage from the rectifier and convert the DC electricity from the first voltage to at least one of a second voltage or a third voltage, the second voltage and the third voltage being less than the first voltage; a rectifier-to-converter line electrically connecting the rectifier to the DC-to-DC converter, wherein DC electricity is configured to flow from the rectifier to the DC-to-DC converter through the rectifier-to-converter line; and a converter-to-rectifier line electrically connecting the DC-to-DC converter to the rectifier, wherein the DC electricity is configured to flow from the DC-to-DC converter to the rectifier through the converter-to-rectifier line, wherein the relay is located within the converter-to-rectifier line, the relay being configured to open the first DC electrical circuit loop within the converter-to-rectifier line and close the first DC electrical circuit loop within the converter-to-rectifier line.

Optionally, the HVAC system may include an equipment control board configured to transmit an activation signal to the relay and close the relay to complete the first DC electrical circuit loop.

Optionally, the equipment control board is configured to transmit the activation signal to the relay to close the relay and complete the first DC electrical circuit loop when activation of the blower motor is desired.

Optionally, the HVAC system may include an equipment control board or a system control unit configured to transmit an activation signal to the relay to close the relay and complete the first DC electrical circuit loop.

Optionally, the HVAC system may include an inverter electrically connected to the rectifier and the DC-to-DC converter, the inverter configured to change the DC electricity received from the rectifier and the DC-to-DC converter to AC converted electricity and provide said AC converted electricity to the blower motor.

Optionally, the HVAC system may include: a converter-to-processor line; a processor-to-inverter line; and a processor electrically connected to the DC-to-DC converter through the converter-to-processor line, the processor being configured to receive DC electricity at the third voltage from the DC-to-DC converter, wherein the processor is electrically connected to the inverter through the processor-to-inverter line and is configured to transmit a blower activation signal to the blower motor through the processor-to-inverter line and the inverter.

Optionally, the HVAC system may include an equipment control board configured to transmit an activation signal to the relay to close the relay and complete the first DC electrical circuit loop, wherein the equipment control board is configured to transmit a blower activation signal to the processor.

Optionally, the HVAC system as defined in any of the preceding statements may be a HVAC system of a transport refrigeration system. Accordingly, in a further aspect of invention, there is provided a transport refrigeration system comprising the HVAC system as defined in any of the preceding statements.

According to another aspect of the invention, a method of operating a heating, ventilation, and air conditioning (HVAC) system having the features according to the first aspect is provided. The method including transmitting an activation signal to the relay located within the first DC electrical circuit loop in the DC electrical circuit of the electronically commutated motor (ECM) controller, the relay being configured to close and complete the first DC electrical circuit loop in response to the activation signal; and operating the blower motor using electricity from the DC electrical circuit.

Optionally, the method may include converting, using an inverter, DC electricity from the DC electrical circuit to AC converted electricity; and providing, using the inverter, the AC converted electricity to the blower motor.

Optionally, the method may include receiving, using the rectifier, AC electricity from the AC input source; converting, using the rectifier, the AC electricity from the AC input source to DC electricity; and providing, using the rectifier, the DC electricity to the DC electrical circuit.

Optionally, the method may include receiving, using the DC-to-DC converter, the DC electricity from the rectifier at a first voltage; converting, using the DC-to-DC converter, the DC electricity from the first voltage to at least one of a second voltage and a third voltage, the second voltage and the third voltage being less than the first voltage; and providing, using the DC-to-DC converter, the DC electricity at the second voltage to the rectifier via the converter-to-rectifier line, wherein the relay is located within the converter-to-rectifier line, the relay being configured to open the first DC electrical circuit loop within the converter-to-rectifier line and close the first DC electrical circuit loop within the converter-to-rectifier line.

Optionally, the method may include transmitting a blower activation signal to a processor within the DC electrical circuit, the processor being configured to receive the DC electricity at the third voltage from the DC-to-DC converter, wherein the processor is electrically connected to an inverter through the processor-to-inverter line; and transmitting, using the processor, the blower activation signal to the blower motor through the processor-to-inverter line and the inverter.

Optionally, the method may include that the activation signal is configured to be transmitted when the blower activation signal is transmitted.

The HVAC system of the second aspect is the HVAC system of the first aspect, optionally in accordance with any optional feature thereof.

According to another aspect of the invention, a computer program product embodied on a non-transitory computer readable medium is provided. The computer program product includes instructions that, when executed by a processor, cause the processor to carry out the method of the second aspect, to perform operations including: transmitting an activation signal to a relay located within a first DC electrical circuit loop in a DC electrical circuit of an electronically commutated motor (ECM) controller, the relay being configured to close and complete the first DC electrical circuit loop in response to the activation signal; and operating a blower motor using electricity from the DC electrical circuit.

Optionally, the computer program product includes instructions that, when executed by a processor, cause the processor to perform operations comprising: transmitting a blower activation signal to a processor within the DC electrical circuit, the processor being electrically connected to an inverter through a processor-to-inverter line, wherein the inverter is configured to convert the DC electricity from the DC electrical circuit to AC converted electricity and provide said AC converted electricity to the blower motor; and transmitting, using the processor, the blower activation signal to the blower motor through the processor-to-inverter line and the inverter.

Optionally, the activation signal is configured to be transmitted when the blower activation signal is transmitted.

The relay is located in a converter-to-rectifier line electrically connecting a DC-to-DC converter and a rectifier within the first DC electrical circuit loop, and wherein the relay is configured to open the first DC electrical circuit loop within the converter-to-rectifier line and close the first DC electrical circuit loop within the converter-to-rectifier line.

Technical effects of embodiments of the present invention include closing a direct current electrical circuit in an ECM controller only when operation of the blower motor is required.

Certain exemplary embodiments will now be described in greater detail, by way of example only, and with reference to the accompanying drawings, in which:.

An ECM for a heating, ventilation, and air conditioning (HVAC) system utilizes a pulse width modulation (PWM) signal to communicate with the furnace or fan coil system control board or ECM controller. The ECM controller may be provided with a three phase electrical current to control operation. The ECM controller may be a variable frequency drive (VFD) configured to control a blower motor of the HVAC system using the three phase electrical current. In traditional systems, the ECM controller may remain connected to an AC input source and constantly consume power even when the blower motor is not in operation, thereby increasing energy costs and carbon consumption. Embodiments disclosed herein incorporate a relay into the ECM controller to control when the ECM controller consumes power.

Referring now to the drawings, <FIG> illustrates a schematic view of an HVAC system <NUM> according to an embodiment of the present invention. Particularly, the HVAC system <NUM> includes a system controller or system control unit <NUM>, an equipment control board <NUM>, an ECM controller <NUM>, and a blower assembly <NUM> (as part of an air handler <NUM>) having a blower motor <NUM> and a centrifugal blower unit <NUM> connected to the duct system <NUM>.

As shown, HVAC system <NUM> operates to heat or cool an environment <NUM>. An air handler unit <NUM>, such as a furnace or fan coil, is provided with air from an inlet air duct <NUM>. Typically, an air filter <NUM> is placed on the inlet air duct <NUM>, and upstream of the blower unit <NUM>. The air filter <NUM> is configured to filter airflow through the duct system <NUM>. The blower unit <NUM> pulls air through the inlet air duct <NUM>, air filter <NUM>, and through the air handler unit <NUM>.

In an embodiment, the blower motor <NUM> may be a dual motor ECM. The system control unit <NUM> is in operative communication with the equipment control board <NUM> over system communication bus <NUM>, which communicates signals between the system control unit <NUM> and the equipment control board <NUM>. As a result of the bidirectional flow of information between the system control unit <NUM> and the equipment control board <NUM>, the algorithms described in illustrated embodiments may be implemented in either control unit <NUM> or the equipment control board <NUM>. Also, in some embodiments, certain aspects of the algorithms may be implemented in control unit <NUM> while other aspects may be implemented in the ECM controller <NUM> or the equipment control board <NUM>.

In one embodiment, the system control unit <NUM> includes a computing system <NUM> having a program stored on non-volatile memory to execute instructions via a microprocessor related to aspects of an airflow rate algorithm to determine the predicted operating parameters of air volume flow, air mass flow, external static pressure load, and operating power consumption of the blower unit <NUM> in HVAC system <NUM>. In embodiments, the microprocessor may be any type of processor (CPU), including a general purpose processor, a digital signal processor, a microcontroller, an application specific integrated circuit, a field programmable gate array, or the like.

The system control unit <NUM> of the illustrated embodiment includes a user interface element <NUM> such as, for example, a graphic user interface (GUI), a CRT display, a LCD display, or other similar type of interface by which a user of the HVAC system <NUM> may be provided with system status and/or the determined operating parameters of the air handler <NUM>. Also, the system control unit <NUM> includes a user input element <NUM> by which a user may change the desired operating characteristics of the HVAC system <NUM>, such as airflow requirements. The user may also enter certain specific aspects of the air handler <NUM> installation such as, for example, the local altitude for operation of the air handler <NUM>, which may be used in the various algorithms. It is to be appreciated that the system control unit <NUM> implements aspects of an airflow control algorithm for determining, in an embodiment, the operating parameters including air volume flow rate or air mass flow rate, the blower unit <NUM> power consumption, and duct static pressure at the extremes of the operating range of the blower motor <NUM> (e.g., at or near maximum motor RPM). The determination of these operating parameters through the algorithms eliminates a need to measure these parameters against published parameters, thereby providing for self-certification of the air handler <NUM> and diagnostics of the HVAC system <NUM>. The equipment control board <NUM> may be located inside of the air handler. The determined operating parameters may be compared to published, expected parameters to provide a certification that the air handler <NUM> meets the published parameters. It should be appreciated that while aspects of the algorithms described above may be executed in the ECM controller <NUM>, in other embodiments, any of the above algorithms may also be executed in the system control unit <NUM> without departing from the scope of the invention.

Also shown, HVAC system <NUM> includes the equipment control board <NUM> operably connected to the blower assembly <NUM> for transmitting operation requests <NUM> to the blower assembly <NUM>. The equipment control board <NUM> may be operably connected to the ECM controller <NUM>. The equipment control board <NUM> includes a processor <NUM> and a memory <NUM>, which stores operational characteristics of blower assembly <NUM> that are specific to the model of the air handler unit <NUM> being used. In some non-limiting embodiments, the operational characteristics include blower diameter, blower operating torque, a cabinet size of the air handler unit <NUM>, and a motor power rating of the blower motor <NUM>.

In one embodiment, the equipment control board <NUM> transmits operation requests <NUM> to the ECM controller via a motor communication bus <NUM>. The ECM controller <NUM> is configured to receive the operation requests <NUM> and control the blower motor <NUM> in accordance with the operation requests <NUM>. The ECM controller <NUM> may also include an associated memory <NUM> and processor <NUM>. The ECM controller <NUM> may be an electronic controller including a processor and an associated memory comprising computer-executable instructions (i.e., computer program product) that, when executed by the processor, cause the processor to perform various operations. The processor may be, but is not limited to, a single-processor or multi-processor system of any of a wide array of possible architectures, including field programmable gate array (FPGA), central processing unit (CPU), application specific integrated circuits (ASIC), digital signal processor (DSP) or graphics processing unit (GPU) hardware arranged homogenously or heterogeneously. The memory may be but is not limited to a random access memory (RAM), read only memory (ROM), or other electronic, optical, magnetic or any other computer readable medium.

The operation requests <NUM> includes a torque command <NUM>. In one embodiment, the equipment control board <NUM> receives operation feedback <NUM> from the ECM controller <NUM> of blower motor <NUM> via the motor communication bus <NUM>. The operation feedback <NUM> includes an operating speed <NUM> of the blower motor <NUM>. In order to determine the operating speed <NUM> of the blower motor <NUM>, the motor control algorithm provides sinusoidal phases currents to the blower motor <NUM> and the operating speed <NUM> of the blower motor <NUM> is directly related to the frequency of the phase currents. The assumption is that the motor is operating in its normal condition where rotor is synched with the rotating magnetic field of the stator.

The ECM controller <NUM> receives the torque commands <NUM> from the equipment control board <NUM> and impels blades of the blower unit <NUM> at the commanded motor operating torque. In an embodiment, the processor <NUM> of the equipment control board <NUM> implements one or more algorithms for determining the air volume flow rate, air mass flow rate, the static pressure in the duct system <NUM> over the full range of duct restrictions and airflow range, and operating power consumption by the blower assembly <NUM> based on the specific characteristic constants of the air handler unit <NUM> including characteristics of the specific blower motor <NUM> and blower unit <NUM> being used.

In an embodiment, for an operating mode of the HVAC system <NUM>, the system control unit <NUM> communicates to the equipment control board <NUM> a command for a desired indoor airflow. The desired indoor airflow depends on user settings such as, for example, the current operating mode, such as heating, cooling, dehumidification, humidification, circulation fan, outside fresh air intake, etc., the number of stages of heating or cooling, and other factors. In some other operating modes, such as gas heating or electric heating, the system control unit <NUM> commands the stages of heat and the equipment control board <NUM> determines the corresponding desired indoor airflow.

Also, the equipment control board <NUM> is in direct communication with the blower assembly <NUM> over motor communication bus <NUM>, which serves to transmit, in one embodiment, torque commands <NUM> from the equipment control board <NUM> to the blower assembly <NUM>. It will be appreciated that the blower assembly <NUM> may send operation feedback <NUM> to the equipment control board <NUM> such as, in one non-limiting example, the operating speed <NUM>. In an embodiment, the equipment control board <NUM> is configured to determine the torque command <NUM> values for the blower motor <NUM>. Further, in an embodiment, the equipment control board <NUM> is configured to determine the external static pressure in the duct system <NUM> that is external to the air handler unit <NUM>.

Referring now to <FIG>, with continued reference to <FIG>, a schematic illustration of the ECM controller <NUM> within the HVAC system <NUM> is illustrated, in accordance with an embodiment of the present invention. An alternating current (AC) input source <NUM> is configured to provide AC electricity to the ECM controller <NUM>. The AC electricity provided to the ECM controller <NUM> includes a positive half-cycle and a negative half-cycle. The first current flow direction I1 represents the flow of electrical current in the HVAC system <NUM> during the positive half-cycle and the second current flow direction I2 represents the flow of electrical current in HVAC system <NUM> during the negative half-cycle. The ECM controller <NUM> include a direct current (DC) circuit <NUM> discussed further herein.

The ECM controller <NUM> includes a rectifier <NUM>, an inverter <NUM>, a DC-to-DC converter <NUM>, the processor <NUM>, and a relay <NUM>. The rectifier <NUM> is electrically connected to the AC input source <NUM> through a first AC input line <NUM> and a second AC input line <NUM>. The AC input source <NUM> is configured to provide AC electricity to the rectifier <NUM>. The rectifier <NUM> is configured to receive AC electricity from the AC input source <NUM> and the rectifier <NUM> is configured to convert the AC electricity to DC electricity.

The inverter <NUM> is electrically connected to the rectifier <NUM> through a rectifier-to-inverter line <NUM> and an inverter-to-rectifier line <NUM>. DC electricity is configured to flow from the rectifier <NUM> to the inverter <NUM> through the rectifier-to-inverter line <NUM>. DC electricity is configured to flow from the inverter <NUM> to the rectifier <NUM> through the inverter-to-rectifier line <NUM>.

The DC-to-DC converter <NUM> is electrically connected to the rectifier <NUM>. The DC-to-DC converter <NUM> is configured to receive DC electricity at a first voltage from the rectifier <NUM> and convert the DC electricity from the first voltage to at least one of a second voltage or a third voltage. The second voltage and the third voltage may be both less than the first voltage. In another embodiment, the DC-to-DC converter <NUM> may be a boost converter and at least one of the second voltage and the third voltage may be greater than the first voltage.

The DC-to-DC converter <NUM> is configured to receive DC electricity from the rectifier <NUM>, convert the voltage of the DC electricity from the rectifier <NUM>, and provide the DC electricity at a reduced or increased voltage to the inverter <NUM>. The DC-to-DC converter <NUM> is configured to convert the DC electricity from the first voltage to the second voltage. In an embodiment, the first voltage is greater than the second voltage, thus the DC-to-DC converter <NUM> is configured to reduce the voltage of the DC electricity from the first voltage to the second voltage. The DC-to-DC converter <NUM> may be configured to provide reduced voltage DC electricity to the inverter <NUM> at the second voltage. In an embodiment, the second voltage is 15V.

The DC-to-DC converter <NUM> is configured to receive DC electricity from the rectifier <NUM>, reduce the voltage of the DC electricity from the rectifier <NUM>, and provide the DC electricity at a reduced voltage to the processor <NUM>. The DC-to-DC converter <NUM> is configured to convert the DC electricity from the first voltage to the third voltage. In an embodiment, the first voltage is greater than the third voltage, thus the DC-to-DC converter <NUM> is configured to reduce the voltage of the DC electricity from the first voltage to the third voltage. The DC-to-DC converter <NUM> may be configured to provide reduced voltage DC electricity to the processor <NUM> at the third voltage. In an embodiment, the third voltage is <NUM>. In one embodiment, the DC-to-DC converter <NUM> may have two direct outputs to produce a third voltage that is different than the second voltage. In another embodiment, there may be a separate linear regulator to produce a third voltage that is different than the second voltage. The separate linear regulator may be located between the DC-to-DC converter <NUM> and the processor <NUM> or between the DC-to-DC converter <NUM> and the inverter <NUM>.

The rectifier <NUM> is electrically connected to the DC-to-DC converter <NUM> through a rectifier-to-converter line <NUM>. The DC-to-DC converter <NUM> is electrically connected to the rectifier <NUM> through a converter-to-rectifier line <NUM>. DC electricity is configured to flow from the rectifier <NUM> to the DC-to-DC converter <NUM> through the rectifier-to-converter line <NUM>. DC electricity is configured to flow from the DC-to-DC converter <NUM> to the rectifier <NUM> through the converter-to-rectifier line <NUM>. The rectifier-to-converter line <NUM> may be electrically connected to the rectifier-to-inverter line <NUM>, as illustrated in <FIG>. The converter-to-rectifier line <NUM> may be electrically connected to the inverter-to-rectifier line <NUM>. The DC bus potential between rectifier-to-converter line <NUM> and the converter-to-rectifier line <NUM> may be 340VDC nominal.

The inverter <NUM> is electrically connected to the DC-to-DC converter <NUM> through a converter-to-inverter line <NUM>. DC electricity is configured to flow from the DC-to-DC converter <NUM> to the inverter <NUM> through the converter-to-inverter line <NUM>. The inverter <NUM> is configured to change DC electricity received from the rectifier <NUM> and the DC-to-DC converter <NUM> to AC converted electricity. The blower motor <NUM> is electrically connected to the inverter <NUM> through an inverter-to-blower motor line <NUM> and the inverter <NUM> is configured to provide the AC converted electricity to the blower motor <NUM> through the inverter-to-blower motor line <NUM>.

The processor <NUM> is electrically connected to the DC-to-DC converter <NUM> through a converter-to-processor line <NUM> and a processor-to-converter line <NUM>. DC electricity is configured to flow from the DC-to-DC converter <NUM> to the processor <NUM> through the converter-to-processor line <NUM>. DC electricity is configured to flow from processor <NUM> to the DC-to-DC converter <NUM> through the processor-to-converter line <NUM>.

The processor <NUM> is electrically connected to inverter <NUM> through a processor-to-inverter line <NUM>. The processor <NUM> is configured to transmit electrical signals or commands for the blower motor <NUM> through the processor-to-inverter line <NUM>.

The ECM controller <NUM> includes a DC electrical circuit <NUM>. The DC electrical circuit <NUM> includes the rectifier <NUM>, the rectifier-to-inverter line <NUM>, the inverter-to-rectifier line <NUM>, the inverter <NUM>, the DC-to-DC converter <NUM>, the rectifier-to-converter line <NUM>, the converter-to-rectifier line <NUM>, the processor <NUM>, the converter-to-processor line <NUM>, and the processor-to-converter line <NUM>. It is understood that the DC electrical circuit <NUM> may include more or less components, as required.

The DC electrical circuit <NUM> may include a first DC electrical circuit loop <NUM> and a second DC electrical circuit loop <NUM>. The first DC electrical circuit loop <NUM> may comprise at least the rectifier <NUM>, the rectifier-to-converter line <NUM>, the DC-to-DC converter <NUM>, and the converter-to-rectifier line <NUM>. The second DC electrical circuit loop <NUM> may comprise at least the rectifier <NUM>, the rectifier-to-inverter line <NUM>, the inverter <NUM>, and the inverter-to-rectifier line <NUM>. The first DC electrical circuit loop <NUM> may be considered a high voltage loop and the second DC electrical circuit loop <NUM> may be considered a high voltage loop. The voltage of the first DC electrical circuit loop <NUM> may be equivalent to the voltage of the second DC electrical circuit loop <NUM>.

The rectifier <NUM> is configured to circulate DC electricity through the DC electrical circuit <NUM>. The relay <NUM> is located within the first DC electrical circuit loop <NUM> of the DC electrical circuit <NUM>. The relay <NUM> may be an electromechanical device or a solid state device. The relay <NUM> is configured to open and close the first DC electrical circuit loop <NUM>. The relay <NUM> may be located within the converter-to-rectifier line <NUM>. Advantageously, locating the relay <NUM> in the converter-to-rectifier line <NUM> after the DC-to-DC converter <NUM> reduces the voltage of the DC electricity, the relay <NUM> will have to withstand a lower voltage than in other parts of the DC electrical circuit <NUM>. In an embodiment, the relay <NUM> is located in series with the rectifier-to-converter line <NUM> and/or the converter-to-rectifier line <NUM>.

The relay <NUM> is configured to open to break the first DC electrical circuit loop <NUM> and close to complete the first DC electrical circuit loop <NUM> within the converter-to-rectifier line <NUM> when commanded by the equipment control board <NUM> in order to reduce standby power consumption of the ECM controller <NUM>. The relay <NUM> controls electrical current flow from the rectifier <NUM> to the DC-to-DC controller <NUM>. If the relay <NUM> is open then electrical current does not flow from the rectifier <NUM> to the DC-to-DC controller <NUM> but if the relay <NUM> is closed then current is allowed to flow from the rectifier <NUM> to the DC-to-DC controller <NUM>.

The equipment control board <NUM> is electrically connected to the relay <NUM> through a system control unit-to-relay line <NUM>. The equipment control board <NUM> is configured to transmit an activation signal <NUM> to the relay <NUM> to close the relay <NUM> and complete the first DC electrical circuit loop <NUM>. In another embodiment, the system control unit <NUM> may be configured to transmit an activation signal <NUM> to the relay <NUM> to close the relay <NUM> and complete the first DC electrical circuit loop <NUM>. The activation signal <NUM> may be a 24VAC signal. The equipment control board <NUM> may only close the relay <NUM> to complete the first DC electrical circuit loop <NUM> when activation of the blower motor <NUM> is desired. Advantageously, if the relay <NUM> is open then electrical current is not allowed to flow from the AC input source <NUM> to the ECM controller <NUM> and thus no energy is wasted.

The equipment control board <NUM> is electrically connected to the processor through a system control unit-to-processor line <NUM>. The equipment control board <NUM> is configured to transmit a blower activation signal <NUM> to the processor <NUM> in order for the processor <NUM> to activate the blower motor <NUM>. The blower activation signal <NUM> could be discrete voltage inputs (e.g. - 24VAC), a PWM command, or digital communication. The blower activation signal <NUM> may be an operation request <NUM> including a torque command <NUM> requesting that the blower motor <NUM>. be operated at a desired torque.

Referring now to <FIG>, with continued reference to <FIG>. <FIG> shows a flow process illustrating a method <NUM> of operating an HVAC system <NUM>, according to an embodiment of the present invention. In an embodiment, the method <NUM> may be performed by the ECM controller <NUM>.

At block <NUM>, an activation signal <NUM> is transmitted to a relay <NUM> located within a first DC electrical circuit loop <NUM> in a DC electrical circuit <NUM> of an ECM controller <NUM>. The relay <NUM> is configured to close and complete the first DC electrical circuit loop <NUM> in response to the activation signal <NUM>, thus allowing the flow of DC electricity through the first DC electrical circuit loop <NUM>. A rectifier <NUM> receives AC electricity from an AC input source <NUM>, converts the AC electricity from the AC input source <NUM> to DC electricity, and provides the DC electricity to the first DC electrical circuit loop <NUM>.

A DC-to-DC converter <NUM> receives the DC electricity from the rectifier <NUM> at a first voltage and converts the DC electricity from the first voltage to at least one of a second voltage and a third voltage. The second voltage and the third voltage being less than the first voltage. The DC-to-DC converter <NUM> then provides the DC electricity at the second voltage to the rectifier <NUM> via a converter-to-rectifier line <NUM>. The relay <NUM> is located within the converter-to-rectifier line <NUM>. The relay <NUM> is configured to open the first DC electrical circuit loop <NUM> within the converter-to-rectifier line <NUM> and close the first DC electrical circuit loop <NUM> within the converter-to-rectifier line <NUM>.

At block <NUM>, a blower motor <NUM> is operated using electricity from the DC electrical circuit <NUM>. An inverter <NUM> converts DC electricity from the DC electrical circuit <NUM> to AC converted electricity and provides the AC converted electricity to the blower motor <NUM>.

The method <NUM> may further include that a blower activation signal <NUM> is transmitted to a processor <NUM> within the DC electrical circuit <NUM>. The processor <NUM> being configured to receive DC electricity at the third voltage from the DC-to-DC converter <NUM>. The processor <NUM> is electrically connected to the inverter <NUM>. through the processor-to-inverter line <NUM>. The processor <NUM> transmits a blower activation signal <NUM> to the blower motor <NUM> through the processor-to-inverter line <NUM> and the inverter <NUM>.

In an embodiment, the activation signal <NUM> is configured to be transmitted when the blower activation signal <NUM> is transmitted. The activation signal <NUM> may only be transmitted when the blower activation signal <NUM> is transmitted. In an embodiment, the activation signal <NUM> may be transmitted first and then the blower activation signal <NUM> may be transmitted after the activation signal <NUM>.

While the above description has described the flow process of <FIG> in a particular order, it should be appreciated that, unless otherwise specifically required in the attached claims, that the ordering of the steps may be varied.

Embodiments can also be in the form of computer program code (e.g., computer program product) containing instructions embodied in tangible media, such as floppy diskettes, CD ROMs, hard drives, or any other non-transitory computer readable medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes a device for practicing the embodiments. Embodiments can also be in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into an executed by a computer, the computer becomes an device for practicing the exemplary embodiments.

Claim 1:
A heating, ventilation, and air conditioning (HVAC) system (<NUM>) comprising:
a blower assembly (<NUM>) comprising a blower motor (<NUM>); and
an electronically commutated motor (ECM) controller (<NUM>) in electrical communication with the blower motor (<NUM>), the ECM controller (<NUM>) comprising:
a rectifier (<NUM>) electrically connected to an alternating current (AC) input source (<NUM>), the rectifier (<NUM>) being configured to receive AC electricity from the AC input source (<NUM>) and convert the AC electricity from the AC input source (<NUM>) to direct current (DC) electricity;
a DC electrical circuit (<NUM>) comprising a first DC electrical circuit loop (<NUM>) and a second DC electrical circuit loop (<NUM>), the rectifier (<NUM>) being configured to circulate the DC electricity through the DC electrical circuit (<NUM>); and
a relay (<NUM>) located within the first DC electrical circuit loop (<NUM>), the relay (<NUM>) being configured to open to break the first DC electrical circuit loop (<NUM>) and close to complete the first DC electrical circuit loop (<NUM>) in order to reduce standby power consumption of the ECM controller (<NUM>);
characterised in that the HVAC system (<NUM>) comprises:
a DC-to-DC converter (<NUM>) electrically connected to the rectifier (<NUM>), the DC-to-DC converter (<NUM>) being configured to receive the DC electricity at a first voltage from the rectifier (<NUM>) and convert the DC electricity from the first voltage to at least one of a second voltage or a third voltage, the second voltage and the third voltage being less than the first voltage;
a rectifier-to-converter line (<NUM>) electrically connecting the rectifier (<NUM>) to the DC-to-DC converter (<NUM>), wherein DC electricity is configured to flow from the rectifier (<NUM>) to the DC-to-DC converter (<NUM>) through the rectifier-to-converter line (<NUM>); and
a converter-to-rectifier line (<NUM>) electrically connecting the DC-to-DC converter (<NUM>) to the rectifier (<NUM>), wherein the DC electricity is configured to flow from the DC-to-DC converter (<NUM>) to the rectifier (<NUM>) through the converter-to-rectifier line (<NUM>),
wherein the relay (<NUM>) is located within the converter-to-rectifier line (<NUM>), the relay (<NUM>) being configured to open the first DC electrical circuit loop (<NUM>) within the converter-to-rectifier line (<NUM>) and close the first DC electrical circuit loop (<NUM>) within the converter-to-rectifier line (<NUM>).