Solar energy based mobile electric vehicle fast charger system

A solar energy based mobile EV fast charger system comprising a stationary solar power supply and a mobile EV fast charger installed in a service truck which has a bidirectional Multi-Functional Power Converter System (MFPCS), a solar energy based on-board battery, multiple DC inductors, a alternator power interface and an universal battery interface provides mobile EV charging service for any EV battery.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. patent application Ser. No. 15/615,647 and hereby incorporates the application by reference.

TECHNICAL FIELD

The present invention relates to non-stationary high power Electric Vehicle (EV) fast charger using a solar based on-board battery as its energy source, capable of providing mobile EV fast charging services for any EV battery, such as but not limited to solar energy based mobile Electric Vehicle (EV) fast charger system.

BACKGROUND

It is well known that Electric Vehicle (EV) can reduce pollution by increasing Mile Per Gallon Equivalent (MPGe) which relies on how EV batteries are charged. In fact EV chargers are facing many challenges. The first challenge is battery charging time, usually up to 8 or 10 hours or more. The second challenge is the lack of EV charging infrastructure resulting in EVs stranding on the road if there is no charging station nearby. The third challenge is that most of energy source used for charging EV battery come from fossil-fuel or coal causing significant reduction of MPGe. The fourth challenge is that EVs have different battery voltage range and current EV DC chargers can only be used for one particular battery voltage range, for example 150v-210V, or 300 v-420 v, or 600 v-840 v. The fifth challenge is that all renewable energy based battery chargers are using multiple power conversions leading to high cost and low efficiency. Therefore, a low cost and high efficient solar energy based mobile EV fast charger system capable of charging any EV battery with different voltage ranges is desired to meet above mentioned challenges.

There are several attempts in prior art addressing the challenges mentioned above separately. For example, Racci (2017/0136902, 2017/0136903) teaches various ways to charge EVs. However Racci's inventions deal with wireless battery charger. Comparing to wired battery charger, wireless battery charger suffers the following deficiencies: increased cost, weight, energy losses and charging noise, limited power, and incompatibility with various EV charging plug-in standards, etc. James (US20160176305A1) teaches a multi-functional power management system (MFPMS) having bidirectional power converters using multi-stage power conversion for residential home, including PV inverter, EV charger, home power system, and power quality correction as shown in his patentFIG. 3. For example, in EV charger mode (as shown in his patentFIGS. 7 and 12) solar energy is converted to HF AC (with power switches1209,1210,1211,1212), HF AC is then converted to DC (with power switches1205,1206,1207,1208), DC is then converted to Grid AC (with power switches1201,1202,1203,1204), finally Grid AC is plugged into an EV on-board charger (OBC) (which itself has another three power stages: Grid AC to DC, DC to HF AC, and then HF AC to EV battery DC https://powerpulse.net/6-6-kw-bi-directional-ev-on-board-charger-reference-design/) to charge an EV battery. It leads to substantial power loss and lower efficiency because of multi-stage power conversion. The techniques disclosed in Pat. Application WO 2012178010 A1, U.S. Pat. No. 6,979,913 B2 and U.S. Pat. No. 7,057,303 B2 represent the prior art of mobile EV chargers which use EV on board charger (OBC) and regular fossil fuel powered generator as its power source to charge EV battery, so that it decreases MPGe significantly and takes longer charging time due to low power of (OBC).

The prior art has not set forth a solar energy based mobile EV fast charger system that has a stationary solar power supply, a bidirectional multi-functional power conversion system (MFPCS) and an universal battery interface. The object of this invention is to provide a solar energy based mobile EV fast charger system that has high power, high efficiency, but low cost, and capable of charging any EV battery with different voltage ranges.

SUMMARY

One non-limiting aspect of the present invention contemplates a multi-function power conversion system (MFPCS) mountable on a vehicle operated as a solar energy based mobile Electric Vehicle (EV) fast charger comprising a three phase Insulated Gate Bipolar Transistor (IGBT) module having a DC port connected to a solar energy source and an on-board battery and a AC port connected to an stationary solar power supply, a Digital Signal Processor (DSP) controller, a DC-link capacitor, a voltage sensor, a DC current sensor, a plurality of AC current sensors and operating in operation mode 6 (i.e., solar energy charging on-board battery and generating AC grid power).

One non-limiting aspect of the present invention contemplates the MFPCS with the AC port connected to a plurality of DC inductors which are connected to the solar energy source and the DC port connected to the on-board battery further operating in operation mode 4 (i.e., solar energy charging on-board battery).

One non-limiting aspect of the present invention contemplates the MFPCS with the AC port connected to a universal battery interface that is connected to an EV battery and the DC port connected to the on-board battery further operating in operation mode 1 (i.e., on-board battery charging EV battery).

One non-limiting aspect of the present invention contemplates the MFPCS with the AC port connected to the universal battery interface that is connected to an EV battery and an alternator interface that is connected to an alternator power, and the DC port connected to the on-board battery further operates in operation mode 2 (i.e., on-board battery and/or alternator power charging EV battery).

One non-limiting aspect of the present invention contemplates the MFPCS with the AC port connected to an alternator interface that is connected to an alternator power, and the DC port connected to the on-board battery further operates in operation mode 3 (i.e., alternator power charging on-board battery).

One non-limiting aspect of the present invention contemplates the MFPCS with the AC port connected to LCL filter plus transformer that is connected to an AC grid power and the DC port connected to the on-board battery further operates in operation mode 5 (i.e., AC grid power charging on-board battery).

One non-limiting aspect of the present invention contemplates the MFPCS further comprising Mode 1 control library used for operation mode 1 consisting of High Frequency (HF) isolated EV fast charger control algorithms, Mode 2 control library used for operation mode 2 consisting of HF isolated EV fast charger control and DC/DC boost converter control algorithms, Mode 3 control library used for operation mode 3 consisting of DC/DC boost battery charger control algorithms, Mode 4 control library used for operation mode 4 consisting of interleaved multi-phase on-board battery charger control algorithms, Mode 5 control library used for operation mode 5 consisting of Pulse Width Modulation (PWM) rectifier battery charger control algorithms, and Mode 6 control library used for operation mode 6 consisting of three phase grid-tied inverter control and direct on-board battery charger control algorithms.

One non-limiting aspect of the present invention contemplates HF isolated EV fast charger control algorithms to charge EV battery with on-board battery comprising an EV battery data base of voltage, current, temperature, state of charge (SOC), age, chemistry, charging requirements for all EV battery system, a battery voltage controller, a battery current controller, a DC current controller, a full bridge PWM unit and an user interface and/or communication interface.

One non-limiting aspect of the present invention contemplates DC/DC boost converter control algorithms to regulate the DC-link voltage of MFPCS with truck alternator power source comprising a DC voltage controller, a DC current controller, and a boost PWM unit.

One non-limiting aspect of the present invention contemplates DC/DC boost battery charger control algorithms to charge on-board battery with truck alternator power comprising a battery voltage controller, a battery current controller, a DC current controller, and a boost PWM unit.

One non-limiting aspect of the present invention contemplates interleaved multi-phase battery charger control algorithms to charge on-board battery with solar energy when solar energy voltage is less than battery voltage (VMP<VB) comprising an optimal solar energy tracking unit, a battery voltage controller, a multi-phase current controller, and an interleaved multi-phase PWM unit.

One non-limiting aspect of the present invention contemplates PWM rectifier battery charger control algorithms to charge on-board battery with AC grid power comprising a battery voltage controller, a battery current controller, an AC current reference generation unit, an AC current controller and a Space Vector Modulation (SVM) unit.

One non-limiting aspect of the present invention contemplates three phase grid-tied inverter control with direct on-board battery charger control algorithms to produce AC grid power and charge on-board battery directly with solar energy when solar energy voltage is greater than battery voltage (VMP>VB) comprising a maximum power point tracking (MPPT) unit, a DC voltage controller, a required battery power calculation unit, an inverter command generation unit, an AC current reference generation unit, an AC current controller, and a SVM unit.

One non-limiting aspect of the present invention contemplates a universal battery interface providing an interface to adapt any EV battery voltage range comprising two identical re-configurable HF transformers, a plurality of transformer re-configuration switches, a diode rectifier circuit, an output L-C filter circuit, and a transformer re-configuration switch control table.

One non-limiting aspect of the present invention contemplates a re-configuration of HF transformers comprising one primary winding and two secondary windings with primary winding connected in parallel while secondary windings connected in combination of series and/or parallel to match mobile EV fast charger voltage with any EV battery.

One non-limiting aspect of the present invention contemplates a plurality of transformer re-configuration switches being controlled based on a transformer re-configuration control table.

DETAILED DESCRIPTION

The following description and the drawings illustrate specific embodiments sufficiently to enable those skilled in the art to practice the system and method described. Other embodiments may incorporate structural, logical, process and other changes. Examples merely typify possible variations. Individual elements and functions are generally optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification. “MFPCS” is defined herein as multi-purpose power converter used to convert DC to DC (DC/DC), or DC to AC (DC/AC), or AC to DC (AC/DC). “IGBT module” is defined as a group of IGBTs packaged into one module. “Power converter” is made of one or several IGBT modules. “IGBT Gate Driver” is defined as an integrated circuit that accepts a low power input from a Digital Signal Processor (DSP) and produces the appropriate voltage and current for an IGBT module. “DSP controller” is defined as a specialized microprocessor with its architecture optimized for the operational needs of digital signal processing. “On-board battery” is defined herein as meaning a large capacity high voltage battery mounted on a service truck and used to charge EV battery. “Battery voltage controller”, “Battery current controller”, “DC voltage controller”, “DC current controller”, “AC current controller” are defined as feedback controllers that consist of Proportional and Integral (PI) controllers which continuously calculate error values as the difference between voltage/current reference and feedback voltage/current and apply correction. “Full Bridge (F.B.) PWM”, “Boost PWM”, “Multi-Phase Interleaved PWM”, “Space vector modulation (SVM)” are defined as pulse width modulation (PWM) techniques used in HF isolated EV fast charger, DC/DC boost converter, interleaved multi-phase on-board battery charger, and three phase inverter respectively. “AC current reference generation” is defined as AC waveform generation technique, its amplitude depends on inverter power command and its frequency depends on the frequency of AC grid power. “Maximum power point tracking (MPPT)” is defined as a technique used with solar power converter to maximize power extraction under all conditions. “Required battery power calculation” is the multiplication of measured battery voltage and required battery charging current.

FIG. 1illustrates a prior art power conversion hardware configuration of solar energy based mobile EV battery charger system10. It consists of three portions: stationary solar power supply12that consists of DC/DC converter314and three-phase inverter22to generate AC grid power18from solar power20(i.e. power converter26converting solar power20to High Frequency (HF) AC28, power converter24converting HF AC28to DC voltage30, and three-phase inverter22converting DC voltage30to three phase AC grid power18), stationary DC fast charger14that consists of three-phase rectifier32and DC/DC converter316to recharge on-board battery42(used as power source in mobile EV charging service) with AC grid power18(i.e. three-phase rectifier32converting three phase AC grid power18to DC voltage38, power converter34converting DC voltage38to HF AC40, then power converter36charging on-board battery42with HF AC40), and mobile EV DC fast charger16(installed on a service truck) that consists of DC/DC converter318to charge EV battery50with on-board battery42. (i.e. power converter44converting DC voltage of on-board battery42to HF AC46, and power converter48charging EV battery50with HF AC46). Therefore, prior art solar energy based mobile EV charger system10consists of eight (8) power converters (22,24,26,32,34,36,44, and48). Each power converter may cause power loss as a result of lower efficiency and high cost. And also system10can only be used for one fixed EV battery voltage range, for example 150v-210 v or 300 v-420 v or 600 v-840 v.

FIGS. 2a-2fillustrate the functional block diagrams of a solar energy based mobile EV fast charger system60operated in operation mode 1 to 6 as disclosed in present invention.FIG. 2aillustrates the operation mode 1 where Stationary Solar Power Supply64may produce AC Grid Power90with Solar Energy80into via power flow320and Mobile EV DC Fast Charger62may charge EV Battery76with On-Board Battery68via power flow322.FIG. 2billustrates the operation mode 2 where Stationary Solar Power Supply64may produce AC Grid Power90with Solar Energy80via power flow320and Mobile EV DC Fast Charger62may charge EV Battery76with On-Board Battery68and/or the Alternator Power70via power flow324.FIG. 2cillustrates the operation mode 3 where Stationary Solar Power Supply64may produce AC Grid Power90with Solar Energy80via power flow320and Mobile EV DC Fast Charger62may charge On-Board Battery68with the Alternator Power70via power flow326.FIG. 2dillustrates the operation mode 4 where Mobile EV DC Fast Charger62may charge On-Board Battery68with Solar Energy80via power flow302.FIG. 2eillustrates the operation mode 5 where Mobile EV DC Fast Charger62may charge On-board Battery68with AC Grid Power90via power flow304.FIG. 2fillustrates the operation mode 6 where Mobile EV DC Fast Charger62may charge On-Board Battery68with part of Solar Energy80via power flow306and feed extra solar energy to AC Grid Power90via power flow308.

FIG. 3illustrates the structure of solar energy based mobile EV fast charger system60. Mobile EV fast charger62mountable on a service truck comprises Multi-Functional Power Conversion Systems (MFPCS)66, Universal Battery Interface74, Alternator Power Interface72, Three DC inductors78, and operation switches SW52, SW254. Stationary Solar Power supply64comprises Three-Phase DC/AC Inverter84, LCL filter Plus Isolation Transformer88, and mobile on-board battery recharging interfaces82,86. MFPCS66is configured and operated in operation mode 1 to 2 to charge EV Battery76, and in mode 3 to mode 6 to charge On-Board Battery68. MFPCS66connected with On-Board Battery68and Universal Battery Interface74may operate in operation mode 1. MFPCS66connected with on-board battery68, Alternator Power Interface72and Universal Battery Interface74may operate in operation mode 2. MFPCS66connected with On-Board Battery68and Alternator Power Interface72may operate in operation mode 3. MFPCS66connected with On-Board Battery68and Three DC Inductors78which are further connected with Solar Energy80through mobile on-board battery recharging interfaces82may operate in operation mode 4. MFPCS66connected with On-Board Battery68and AC Grid Power90through mobile on-board battery recharging interfaces86may operate in operation mode 5. MFPCS66connected with On-Board Battery68and Stationary Solar Power Supply64which is further connected with Solar Energy80and AC Grid Power90may operate in operation mode 6. Stationary Solar Power Supply64may operate as a three-phase grid-tied solar power converter to produce AC Grid Power90with Solar Energy80when it is not connected to Mobile EV DC Fast Charger62.

FIG. 4aillustrates the block diagram of a bidirectional Multi-Functional Power Conversion Systems (MFPCS)66and its complement of power sources available for switching in or out of use as provided by the disclosed functionality. Power sources may be connected to either DC Port310or AC Port312. MFPCS66configuration examples are shown inFIG. 4afor the power converter functions in six (6) operation modes. The present design of MFPCS66may provide converter facilities and functionalities using hardware and control algorithms potentially including a tailored set of logic and operations to realize the desired operating capabilities disclosed herein.

FIG. 4bschematically illustrates the structure of MFPCS66comprising Insulated Gate Bipolar Transistor (IGBT) Module104which is connected to DC-Link Capacitor110, DC Port310, AC Port312and mounted on liquid cooled Heatsink106, Digital Signal Processor (DSP) Controller128, DC Current Sensor102, Primary Current Sensors108, and Voltage Sensor100. The IGBT module is made of six (6) IGBT switches112,114,116,118,120,122. Primary Current Sensors108sense currents of Universal Battery Interface74or Three DC Inductors78or Alternator Power Interface72or AC Grid Power90(inFIG. 3) depending on the operation mode and the power source connected to AC Port312. DC Current Sensor102senses currents of Solar Energy80or On-Board Battery68(inFIG. 3) depending on the operation mode and the power source connected to DC Port310. Voltage Sensor100senses the voltage of the DC Port310. DSP Controller128comprises Mode 1 control library130with High Frequency (HF) isolated EV fast charger control algorithms, Mode 2 control library132with HF isolated EV fast charger control and DC/DC boost converter control algorithms, Mode 3 control library134with DC/DC boost battery charger control algorithms, Mode 4 control library136with interleaved multi-phase on-board battery charger control algorithms, Mode 5 control library138with PWM rectifier battery charger control algorithms, and Mode 6 control library140with three phase grid-tied inverter and direct on-board battery charger control algorithms. With the sensed voltage and current, DSP Controller128may implement one of control algorithms in Mode Control Libraries 1 or 2 or 3 or 4 or 5 or 6 for operation mode 1 or 2 or 3 or 4 or 5 or 6 respectively by providing control signals to IGBT Gate Driver124. With the control signals, IGBT Gate Driver124may produce gate drive signals with appropriate voltage and current for IGBT Module104to provide battery charging and power conversion functions in operation mode 1 to 6.

FIG. 5schematically illustrates configurations of an exemplary Mobile EV Fast Charger62in operation mode 1 or mode 2 or mode 3. In operation mode 1 DC-Link Capacitor110of MFPCS66through DC Port310is connected to On-Board Battery68and IGBT switches112,114,120,122of MFPCS66through AC Port312are connected to Universal Battery Interface74which is further connected to EV Battery76, Mode 1 Control Library130in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that EV Battery76is charged with On-Board Battery68. Comparing two (2) IGBT modules44,48being used in prior art ofFIG. 1, the operation mode 1 only uses one (1) IGBT Module104to charge EV Battery76with On-Board Battery68. In operation mode 2 IGBT switches116,118of MFPCS66are connected to Alternator Power Source70through AC Port312and Alternator Power Interface72which consists of an inductor and a capacitor, DC-Link Capacitor110of MFPCS66through DC Port310is connected to On-Board Battery68and IGBT switches112,114,120,122of MFPCS66through AC Port312are connected to Universal Battery Interface74which is further connected to EV Battery76, Mode 2 Control Library132in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that EV Battery76is charged with On-Board Battery68and/or Alternator Power Source70. Comparing two (2) IGBT modules44,48being used in prior art ofFIG. 1, the operation mode 2 only use one (1) IGBT Module104to charge EV Battery76with On-Board Battery68and/or Alternator Power70. In operation mode 3 DC-Link Capacitor110of MFPCS66through DC Port310is connected to On-Board Battery68and IGBT switches116,118of MFPCS66are connected to Alternator Power Source70through AC Port312and Alternator Power Interface72which consists of an inductor and a capacitor, Mode 3 Control Library130in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that On-Board Battery68is charged with Alternator Power Source70.

FIG. 6schematically illustrates configurations of an exemplary solar energy based mobile EV fast charger system60in operation mode 4 or mode 5 or mode 6. In operation mode 4 where solar energy voltage is less than on-board battery voltage (VMP<VB), IGBT switches112,114,116,118,120,122of MFPCS66are connected to Solar Energy Source80through AC Port312, Three DC Inductors78and mobile on-board battery recharging interface82with operation switch SW254closed, DC-Link Capacitor110of MFPCS66through DC Port310is connected to On-Board Battery68, Solar Energy80is dis-connected to On-Board Battery68with operation switch SW152open, Mode 4 Control Library136in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that On-Board Battery68is charged with Solar Energy Source80. Comparing six (6) IGBT modules22,24,26,32,34,36being used in prior art ofFIG. 1, the operation mode 4 only use one (1) IGBT Module104to charge On-Board Battery68with Solar Energy Source80. In operation mode 5 MFPCS66is connected to On-Board Battery68through DC Port310and connected to AC Grid Power90through AC Port312, mobile on-board battery recharging interface86, and LCL filter Plus Isolation Transformer88, Mode 5 Control Library138in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that On-Board Battery68is charged with AC Grid Power90. Comparing three (3) IGBT modules32,34,36being used in prior art ofFIG. 1, the operation mode 5 only use one (1) IGBT Module104to charge On-Board Battery68with AC Grid Power90. In operation mode 6 where solar energy voltage is greater than on-board battery voltage (VMP>VB), MFPCS66is connected to On-Board Battery68and Solar Energy80through DC Port310and mobile on-board battery recharging interface82with operation switch SW152closed, and connected to AC Grid Power90through AC Port312, mobile on-board battery recharging interface86, and LCL Filter Plus Isolation transformer88, Mode 6 Control Library140in DSP Controller128generates control signals for IGBT Gate Driver124to control IGBT Module104(inFIG. 4b) so that a part of Solar Energy80is used to charge On-Board Battery68and extra solar energy is fed to AC Grid Power90. Comparing six (6) IGBT modules22,24,26,32,34,36being used in prior art ofFIG. 1, the operation mode 6 only use one (1) IGBT Module104to charge On-Board Battery68and to produce AC Grid Power90with Solar Energy Source80.

FIG. 7illustrates the block diagram of HF isolated EV fast charger control algorithms150in Mode 1 and Mode 2 Control Libraries. Control algorithms150incorporates EV Battery Data Base152providing battery voltage reference Vbr and battery current reference Ibr to battery voltage controller154and battery current controller156based on the battery information including but not limited to EV manufacturer and model number, chemistry, voltage and current ranges, State of Charge (SOC), temperatures and charging requirements of EV batteries. The battery voltage Vb is regulated to battery voltage reference Vbr by battery voltage controller154in constant voltage mode; the battery current Ib is regulated to battery current reference Ibr by battery current controller156in constant current mode. Using the output from either voltage control154or current control156, DC current controller158regulates output current Idc56(inFIG. 5) by commanding Full-Bridge (F.B) PWM160to generate PWM signals controlling IGBTs112,114,120,122of MFPCS66to charge EV battery76with on-board battery68(inFIG. 5). User and/or Communication Interface164allows users to select the EV model from EV Battery Data Base152so that the corresponding hardware configuration and battery charging control algorithms can be selected before the battery charging process begin.

FIG. 8illustrates the functional block diagram of DC/DC boost converter control algorithms170in Mode 2 Control library which is used in operation mode 2. DC voltage controller172regulates the voltage Vdc of DC-link capacitor110in MFPCS66(inFIG. 5) with reference Vdcr by generating a boost current reference Ibstr for DC current controller174. Current controller174regulates the boost current Ibst58(inFIG. 5) with the boost current reference Ibstr by generating a PWM command voltage Vm. Boost PWM176generates PWM signals based on the PWM command voltage Vm controlling IGBT switches116,118of MFPCS66to boost a low voltage of truck Alternator Power Source70to a high voltage of DC-Link Capacitor110in MFPCS66so as to charge EV Battery76with the high voltage of DC-Link Capacitor110(inFIG. 5).

FIG. 9illustrates the functional block diagram of DC/DC boost battery charger control algorithms180in Mode 3 Control Library which is used in operation mode 3. Battery voltage controller182regulates battery voltage Vb to battery voltage reference Vbr by generating a DC current reference Ibstr in constant voltage mode, battery current controller184regulates battery current Ib to battery current reference Ibr by generating a DC current reference Ibstr in constant current mode. DC current controller186regulates boost current Ibst58(inFIG. 5) to DC current reference Ibstr by commanding Boost PWM188to generate PWM signals controlling IGBT switches116,118of MFPCS66to charge On-Board Battery68with truck Alternator Power Source70(inFIG. 5).

FIG. 10illustrates the functional block diagram of interleaved multi-phase on-board battery charger control algorithms196in Mode 4 Control Library which is used in operation mode 4. Battery voltage controller198regulates battery voltage to battery voltage reference Vbr by generating DC current reference Impr202in constant voltage mode. Optimal Solar Tracking unit200regulates battery current by generating DC current reference Impr202in constant current mode. In Optimal Solar Tracking unit200, battery voltage Vb192and solar voltage Vmp190are used by function block178to derive the inverse duty cycle: 1/1−D (162)=Vb(192)/VMP(190). Solar current reference Impr202is related to battery charging current reference Ibr194by the expression: Impr=1/1−D×Ibr. Impr202is fed into multi-phase current controller204to regulate inductor currents IL1142, IL2144, IL3146of DC inductors78(inFIG. 6) by commanding Multi-Phase Interleaved PWM206to generate signals controlling IGBT switches112,114,116,118,120,122of MFPCS66to charge On-Board Battery68with Solar Energy80(inFIG. 6).

FIG. 11illustrates the functional block diagram of PWM rectifier battery charger control algorithms210in Mode 5 Control Library which is used in operation mode 5. Battery voltage controller212regulates battery voltage Vb to battery voltage reference Vbr by generating an inverter power command Pinv in constant voltage mode, battery current controller214regulates battery current Ib to battery current reference Ibr by generating an inverter power command Pinv in constant current mode. AC Current Reference Generation unit216produces AC current references Iacr with the inverter power command Pinv. AC current controller218regulates AC currents Ia94, Ib96, Ic98in LCL Filter Plus Isolation Transformer88by commanding Space Vector Modulation (SVM)220to generate PWM signals controlling IGBT switches112,114,116,118,120,122of MFPCS66to charge On-Board Battery68with AC Grid Power90(inFIG. 6).

FIG. 12illustrates the functional block diagram of three phase grid-tied inverter and direct on-board battery charger control algorithms230in Mode 6 Control Library which is used in operation mode 6. Maximum Power Point Tracking (MPPT) unit240extracts the maximum solar power by producing a dynamic voltage reference Vmr to DC voltage controller242. DC voltage controller242regulates solar power output voltage Vmp190to dynamic voltage reference Vmr by generating solar power command Ps244. Required Battery Power Calculation232produces required on-board battery charging power Pb238based on on-board battery charging current reference IBR236and on-board battery voltage VB234. Inverter command generation unit248produces inverter power command Pinv246by subtracting required on-board battery charging power Pb238from solar power command Ps244. Inverter power command Pinv246is then fed to AC Current Reference Generation250to create a current reference Iacr for AC current controller252which regulates AC currents Ia94, Ib96, Ic98in LCL Filter Plus Isolation Transformer88by commanding SVM254to generate PWM signals controlling IGBT switches112,114,116,118,120,122of MFPCS66to charge On-Board Battery68and produce AC Grid Power with Solar Energy90(inFIG. 6).

FIG. 13illustrates Universal Battery Interface74comprising two identical HF transformers270each having one primary winding and two separated secondary windings, Transformer Reconfiguration Switches272reconfiguring HF transformer's secondary windings in series and/or parallel, Diode Rectifier circuit274converting an AC voltage pulse trains to DC ones, Output L-C Filter276eliminating HF switching harmonic components, may be reconfigured by MFPCS66(inFIG. 3) through opening and closing of switches CT1278, CT2280, CT3282, CT4284, CT5286, CT6288, CT7290, CT8292, CT9294based on transformer re-configuration switch control table300as shown inFIG. 14so that it can interface with EV battery with any voltage range, for example 150 v-210V, 300 v-420 v, 600 v-840 v.