System and method for power management and control

Abstract

To provide a system and a method for suitable power management and control.SOLUTION: Systems and methods directed to improved battery management, motor control, energy storage, and battery charging. The systems and methods provide a paradigm change platform that allows for the motorization of vehicles and allows for the integration of battery management, charging, and motor control with means to manage regenerative braking, traction, and handling. In embodiments, systems and methods are directed to a unified modular battery pack system having a cascaded architecture comprising, as building blocks, an integrated combination of a networked low-voltage converter / controller with peer-to-peer communication capability, an embedded ultracapacitor or other secondary energy storage element, a battery management system, and a series-connected set of individual cells.SELECTED DRAWING: Figure 21

Description

[Technical Field]

[0001] The present disclosure relates to power management and control of battery systems, and more particularly to systems and methods that facilitate improved battery management, motor control, energy storage, and battery charging for electric vehicles and other stationary applications. [Background technology]

[0002] Today's automotive technology, as developed over the past century, is characterized by the interplay of, among other things, motors, mechanical elements, and electronics. These are key components that influence vehicle performance and the driver experience. Motors can be combustion or electric, and typically one motor is found per vehicle. Exceptions include vehicles with hybrid drivetrains, which feature a combination of a combustion engine with one or two electric motors, or performance-oriented electric vehicles equipped with two motors. In almost all cases, rotational energy from the motor is delivered through a highly sophisticated set of mechanical elements, including clutches, transmissions, differentials, driveshafts, torque tubes, and couplers. These components largely control torque conversion and power distribution to the wheels and are key factors in defining a vehicle's performance. They also affect road handling. Over the years, individual vehicle manufacturers have highly optimized these mechanical components to provide better performance, greater fuel efficiency, and ultimately, market differentiation. On the control side, aside from driver comfort such as entertainment, navigation, and human-machine interface elements, there are typically only a few clusters of specialized electronic hardware and embedded software that control / optimize motor, clutch / transmission operation, and road-keeping / handling.

[0003] Today's electric automobiles or vehicles (EVs) have largely adopted most of the century-old design paradigm of combustion vehicles, with the obvious substitution of batteries, charging systems, and electric motors for the usual gas tank, fuel pump / injector, and combustion engine. While the control electronics are adapted to the component differences, it is important to recognize that most of the mechanical drivetrain parts described above are still present (see, for example, Figures 1A and 1B). This means that the overall design philosophy of current EVs only marginally moves beyond the traditional paradigm. Thus, the true potential of electrification has not been realized.

[0004] An EV includes various electrical systems associated with the drivetrain, including, among other things, the battery, charger, and motor control. A short inventory of the current capabilities and shortcomings of these electrical systems includes the following:

[0005] (Traditional battery design) Currently, high-voltage battery packs are typically organized as a series chain of low-voltage battery modules. Each such module further consists of a series-connected set of individual cells and a simple built-in battery management system to regulate basic cell-related characteristics such as state of charge and voltage. Electronics with more sophisticated capabilities or some form of smart interconnectivity are lacking. As a result, any monitoring or control functions are handled by separate systems, which, even if present elsewhere in the vehicle, lack the ability to monitor individual cell health, state of charge, temperature, and other performance-affecting metrics. Nor does the ability to regulate power draw per individual cell in any way exist. Some of the major consequences are: (1) the weakest cell will inhibit the overall performance of the entire battery pack; (2) failure of any cell or module will lead to the need to replace the entire pack; (3) battery reliability and safety will be significantly reduced; (4) battery life will be limited; (5) thermal management will be difficult; (6) the battery pack will always operate below its maximum capacity; and (7) the surge of power into the battery pack from regenerative braking cannot be easily stored within the battery and will require dissipation through a dump resistor.

[0006] (Current charger design) Charging circuits are typically implemented in separate, on-board systems. They step up power coming from outside the EV in the form of an AC or DC signal, convert it to DC, and deliver it to the battery pack. The charging system monitors voltage and current and typically provides a steady, constant delivery. Given the design of the battery pack and typical charging circuitry, there is little ability to tailor charge flow to individual battery modules based on cell health, performance characteristics, temperature, etc. Charging cycles are also typically long because the charging system and battery pack lack circuitry to enable pulse charging or other techniques that would optimize charge transfer or achievable total charge.

[0007] (Current Motor Control Design) Conventional controls include a DC-DC conversion stage to adjust the battery pack voltage level to the bus voltage of the EV's electrical system. The motor is then driven by a simple two-level multi-phase converter, which then provides the required AC signal to the electric motor. Each motor is traditionally controlled by a separate controller, driving the motor in a three-phase design. A dual-motor EV would require two controllers, while an EV using four in-wheel motors would require four individual controllers. Conventional controller designs also lack the ability to drive next-generation motors, such as switched reluctance motors (SRMs), which are characterized by a larger number of magnetic pole pieces. Adaptation would require a high-phase design, making the system more complex and ultimately unable to cope with electrical noise and drive performance, such as high torque ripple and acoustic noise.

[0008] In light of the aforementioned limitations, systems and methods that facilitate improved battery management, motor control, power storage, and battery charging are desirable to address the above-mentioned shortcomings and provide a paradigm-changing platform. Summary of the Invention [Problem to be solved by the invention]

[0009] Embodiments of the present disclosure are directed to systems and methods that facilitate improved battery management, motor control, energy storage, and battery charging. Accordingly, the systems and methods provided herein enable the realization of the true potential of vehicle electrification, providing a paradigm-changing platform that intelligently integrates battery management, charging, and motor control with means for managing regenerative braking, traction, and handling. [Means for solving the problem]

[0010] Exemplary embodiments of the present disclosure are directed to a unified modular battery pack system, preferably having a cascaded architecture with, as its building blocks, an integrated combination of networked low-voltage converters / controllers with peer-to-peer communication capabilities, embedded ultracapacitors or other secondary energy storage elements, a battery management system, and a series-connected set of individual cells. Such an interconnected assembly of intelligent battery modules effectively becomes a smart electrical "neural network" and a replacement for (1) the charging system, (2) the battery management module, (3) the DC-DC converter, and (4) the motor controller.

[0011] This modular smart battery pack system can be combined not only with conventional EV motors and drivetrains, but also with new in-wheel EV motors being developed for use in future EVs.

[0012] In the exemplary embodiments provided herein, the electronics of each modular smart battery pack is based on a multi-level controller, which in one exemplary embodiment is preferably a bidirectional multi-level hysteretic controller combined with a temperature sensor and networking interface logic. This design offers a long list of advantages: (1) improved battery utilization through individual switching of modules based on their age, thermal condition, and performance characteristics; (2) reduced heat loss within the cells through careful power consumption or generation balancing; (3) slower cell aging through better individual thermal management and filtering of higher current harmonics; (4) the ability to monitor battery health with granularity and provide early warning of the need for inspection; (5) a fail-safe and redundant design that can maintain drivability even under individual module failure; (6) higher efficiency and better economy through the use of new semiconductor technologies that operate at lower component voltages, reducing power losses and costs; (7) software-based optimization of the topology and control method to suit different vehicle characteristics; (8) near-perfect recovery of energy from regenerative braking and fast response to acceleration due to built-in ultracapacitors; and (9) ultra-fast pulse speeds driven by intelligent controller circuitry. (10) Reduced electromagnetic interference and susceptibility of the circuit topology; (11) Adaptive neural net-based coordination between modules to improve overall system performance, response time, thermal management, and collective system efficiency; (12) Elimination of mechanical drivetrain components and associated losses when combined with in-wheel motors; (13) Reduced overall drivetrain magnetic and electrical losses; (14) Increased power density when used with in-wheel motors; (15) Reduced torque ripple and increased passenger comfort due to reduced electrical and mechanical noise from refined motor control and electrical filtering; (16) Ability to fit and be optimized for all current and next generation motor designs; (17) Reduced space providing more room for passengers / cargo / additional batteries (more range); (18) Better performance, higher vehicle efficiency.(19) Providing a longer driving range, reduced weight, (20) Superior handling and better traction when combined with in-wheel motors, (21) A universal building block adaptable for use in vehicles from small passenger cars to large buses and commercial trucks, and (22) Offering software-based differentiation of vehicle characteristics instead of through traditional mechanical component design.

[0013] Other systems, methods, features and advantages of the illustrative embodiments will be, or become, apparent to one with skill in the art upon examination of the following figures and detailed description. The present specification also provides, for example, the following items: (Item 1) An electric vehicle, A chassis, three or more wheels operably coupled to the chassis; one or more electric motors operably coupled to the three or more wheels; one or more intelligent modular battery packs operably coupled to the one or more motors; a control system operably coupled to the one or more battery packs and the one or more motors; An electric vehicle equipped with (Item 2) Item 1. The electric vehicle of item 1, wherein the chassis is drivetrain-less. (Item 3) Item 1. The electric vehicle according to item 1, wherein the one or more motors are in-wheel motors. (Item 4) Item 1. The electric vehicle of item 1, wherein the one or more intelligent modular battery packs have a cascaded architecture. (Item 5) Item 5. The electric vehicle of item 4, wherein the battery pack comprises a plurality of interconnected intelligent battery modules. (Item 6) Item 6. The electric vehicle of item 5, wherein the battery module comprises an integrated combination of a networked low-voltage converter / controller with peer-to-peer communication capabilities, an embedded ultracapacitor, a battery management system, and a series-connected set of individual cells. (Item 7) Item 1. The electric vehicle of item 1, wherein the battery pack comprises a neural network comprising a plurality of interconnected intelligent battery modules. (Item 8) Item 6. The electric vehicle of item 5, wherein the battery module comprises an integrated combination of a battery with a BMS, a supercapacitor module, and an output converter. (Item 9) Item 9. The electric vehicle of item 8, wherein the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank. (Item 10) Item 9. The electric vehicle of item 8, wherein the output converter comprises a four-quadrant H-bridge. (Item 11) Item 1. The electric vehicle of item 1, wherein the control system comprises a bidirectional multilevel controller. (Item 12) Item 12. The electric vehicle of item 11, wherein the bidirectional multilevel controller is a bidirectional multilevel hysteresis controller. (Item 13) Item 12. The electric vehicle of item 11, wherein the bidirectional multilevel controller is combined with a temperature sensor and networking interface logic. (Item 14) 14. The electric vehicle of claim 11, wherein the control system is configured to balance battery utilization through individual switching of modules based on module age, thermal conditions, and performance characteristics. (Item 15) The electric vehicle of items 1-14, wherein the battery pack is switchable to rectifier / charger operation. (Item 16) An intelligent modular battery pack comprising a cascaded architecture comprising a plurality of interconnected intelligent battery modules. (Item 17) Item 17. The intelligent modular battery pack of item 16, wherein the battery module comprises an integrated combination of a networked low-voltage converter / controller with peer-to-peer communication capabilities, an embedded ultracapacitor, a battery management system, and a series-connected set of individual cells. (Item 18) Item 17. The intelligent modular battery pack of item 16, wherein the interconnected intelligent battery modules comprise a neural network. (Item 19) Item 17. The intelligent modular battery pack of item 16, wherein the battery module comprises an integrated combination of a battery with a BMS, a supercapacitor module, and an output converter. (Item 20) 20. The intelligent modular battery pack of item 19, wherein the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank. (Item 21) 20. The intelligent modular battery pack of item 19, wherein the output converter comprises a four-quadrant H-bridge. (Item 22) An intelligent battery module comprising an integrated low-voltage converter / controller with peer-to-peer communication capabilities, a built-in ultracapacitor, a battery management system, and multiple series-connected sets of individual cells. (Item 23) Item 23. The intelligent battery module of item 22, wherein the converter / controller comprises a four-quadrant H-bridge. (Item 24) An intelligent battery module, comprising: a battery with an integrated BMS; a supercapacitor module operably coupled to the battery; an output converter operably coupled to the battery and the supercapacitor module; An intelligent battery module comprising: (Item 25) Item 25. The intelligent battery module of item 24, wherein the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank. (Item 26) Item 25. The intelligent battery module of item 24, wherein the output converter comprises a four-quadrant H-bridge.

[0014] Details of illustrative embodiments, including structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts. The components within the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the present disclosure. Moreover, all illustrations are intended to convey the concept, in which relative size, shape, and other detailed attributes may be depicted diagrammatically, rather than literally or precisely. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 illustrates a simplified schematic diagram of the power electronics circuitry and electric motor of a conventional battery electric vehicle.

[0016] [Figure 2] FIG. 2 illustrates a schematic diagram of a power electronics circuit and electric motor for a battery electric vehicle according to an embodiment of the present disclosure having a unified modular system with a cascaded architecture including an intelligent modular AC battery pack with a series connection of intelligent low-voltage battery modules.

[0017] [Figure 3A]3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3A shows a high-voltage battery pack comprising a series chain of low-voltage battery modules. [Figure 3B] 3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3B shows each battery module comprising a series connection of low-voltage battery cells and an integrated battery management or control system. [Figure 3C] 3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3C shows a high-voltage DC / AC converter split into multiple low-voltage DC / AC converters in series. [Figure 3D] 3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3D shows individual low-voltage DC / AC converters integrated within individual battery modules. [Figure 3E] 3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3E shows ultra- or super-capacitors integrated within individual battery modules for intermittent storage of braking power inrush. [Figure 3F]3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3F shows a high-voltage intelligent modular AC battery pack comprising a series connection of low-voltage intelligent battery modules integrated with a battery management or control system, a low-voltage converter, and an ultracapacitor. [Figure 3G] 3A-3I illustrate schematic diagrams showing a power electronics circuit according to an embodiment of the present disclosure as an intelligent modular representation of the conventional high-voltage power electronics circuit for a battery electric vehicle shown in FIG. 1. Figures 3G and 3H show the DC / DC converter removed from the power electronics circuit. [Figure 3H] 3A-3I illustrate schematic diagrams showing a power electronics circuit according to an embodiment of the present disclosure as an intelligent modular representation of the conventional high-voltage power electronics circuit for a battery electric vehicle shown in FIG. 1. Figures 3G and 3H show the DC / DC converter removed from the power electronics circuit. [Figure 3I] 3A-3I illustrate schematic diagrams showing power electronics circuits according to embodiments of the present disclosure as intelligent modular representations of conventional high-voltage power electronics circuits for battery electric vehicles shown in FIG. 1. FIG. 3I shows the AC / DC converter / charger removed from the power electronics circuit.

[0018] [Figure 4] FIG. 4 illustrates a perspective view of a conceptual representation of an intelligent battery module comprising a battery integrated with a battery management and control system, a low-voltage converter, and an ultracapacitor, according to an embodiment of the present disclosure.

[0019] [Figure 5]FIG. 5 illustrates a schematic diagram of an intelligent battery module coupled to a battery module control system (or local electronic control unit (ECU)) and a master control system (or master ECU), according to an embodiment of the present disclosure.

[0020] [Figure 6] FIG. 6 illustrates a schematic diagram of multiple intelligent modular AC battery packs coupled to a three-phase motor and a charging coupling for coupling to a single or three-phase grid or power source, according to an embodiment of the present disclosure.

[0021] [Figure 7] 7A and 7B illustrate graphs of typical waveforms of the output voltage for one intelligent battery module (FIG. 7A) and one phase of an intelligent modular AC battery pack with six intelligent battery modules connected in series in each phase (FIG. 7B).

[0022] [Figure 8] 8A, 8B, 8C, and 8D illustrate graphs showing the principles of the phase shift carrier technique.

[0023] [Figure 9] FIG. 9 illustrates a schematic diagram of a functional diagram of a voltage level selector of a nine-level four-quadrant hysteretic controller.

[0024] [Figure 10] 10A, 10B, and 10C illustrate graphs showing the operation of a nine-level, four-quadrant hysteretic controller. FIG. 10A illustrates the current control error IERROR as the difference between IIREAL and IREF. FIG. 10B illustrates the reference current IREF and the actual current IREAL in the motor phase. FIG. 10C illustrates the converter output voltage VOUT.

[0025] [Figure 11]FIG. 11 illustrates a functional diagram of a nine-level four-quadrant hysteretic current controller with state-of-charge (SOC) balancing and zero-state rotation.

[0026] [Figure 12] FIG. 12 illustrates a functional diagram of the intelligent battery module rotation controller.

[0027] [Figure 13] FIG. 13 illustrates a functional diagram of the di / dt estimator.

[0028] [Figure 14A] 14A and 14B illustrate functional diagrams of the -0 VDC Rotate (FIG. 14A) and +0 VDC Rotate (FIG. 14B) blocks. [Figure 14B] 14A and 14B illustrate functional diagrams of the -0 VDC Rotate (FIG. 14A) and +0 VDC Rotate (FIG. 14B) blocks.

[0029] [Figure 15A] 15A and 15B illustrate functional diagrams of the +1 VDC Rotation (FIG. 15A) and −1 VDC Rotation (FIG. 15B) blocks. [Figure 15B] 15A and 15B illustrate functional diagrams of the +1 VDC Rotation (FIG. 15A) and −1 VDC Rotation (FIG. 15B) blocks.

[0030] [Figure 16] 16A, 16B, 16C, and 16D illustrate functional diagrams of a 0 VDC rotary generator (FIG. 16A), a 1 VDC rotary generator (FIG. 16B), a 2 VDC rotary generator (FIG. 16C), and a 3 VDC rotary generator (FIG. 16D).

[0031] [Figure 17] FIG. 17 illustrates a schematic diagram of the centralized connection of all intelligent modules to a master ECU for State of Charge (SOC) balancing.

[0032] [Figure 18]FIG. 18 illustrates a flow diagram of structural power flow management within an intelligent battery module.

[0033] [Figure 19] FIG. 19 illustrates a circuit diagram showing the topology of the intelligent battery module and the current in node 1.

[0034] [Figure 20] FIG. 20 illustrates a graph of the current in the intelligent battery module when the supercapacitor module operates as an active filter.

[0035] [Figure 21] FIG. 21 illustrates a single-phase intelligent battery pack connected to a single-phase load.

[0036] [Figure 22] FIG. 22 illustrates a three-phase intelligent battery pack connected to a switched reluctance motor. DETAILED DESCRIPTION OF THE INVENTION

[0037] It should be noted that elements of similar structure or function are generally represented by like reference numerals throughout the figures for illustrative purposes, and that the figures are intended only to facilitate the description of preferred embodiments.

[0038] The following embodiments are described in detail to enable those skilled in the art to make and use various embodiments of the present disclosure. It is to be understood that other embodiments will be apparent based on this disclosure, and that system, process, or modifications may be made without departing from the scope of the present embodiments.

[0039] Embodiments of the present disclosure are directed to systems and methods that facilitate improved battery management, motor control, energy storage, and battery charging. Accordingly, the systems and methods provided herein enable the realization of the true potential of vehicle electrification, providing a paradigm-changing platform that intelligently integrates battery management, charging, and motor control with means for managing regenerative braking, traction, and handling.

[0040] Exemplary embodiments of the present disclosure are directed to a unified modular battery pack system, preferably having a cascaded architecture with, as its building blocks, an integrated combination of networked low-voltage converters / controllers with peer-to-peer communication capabilities, embedded ultracapacitors, a battery management system, and a series-connected set of individual cells. Such an interconnected assembly of intelligent battery modules effectively becomes a smart electrical "neural network" and a replacement for (1) the charging system, (2) the battery management module, (3) the DC-DC converter, and (4) the motor controller.

[0041] This modular smart battery pack system can be combined not only with conventional EV motors and drivetrains, but also with new in-wheel EV motors being developed for use in future EVs.

[0042] In exemplary embodiments provided herein, the electronic device is based on a bidirectional multilevel controller combined with a temperature sensor and networking interface logic. In an exemplary embodiment, the bidirectional controller is a bidirectional multilevel hysteretic controller.

[0043] Referring in detail to the figures, a simplified schematic diagram of a conventional power electronics circuit 10 and electric motor 70 is shown in Figure 1. As shown in Figure 1, the power electronics circuit 10 typically includes a charger 20 having an AC-DC converter, a high-voltage battery pack 30 electrically coupled to the charger 20, a DC-DC converter 40 electrically coupled to the high-voltage battery pack 30, a DC-AC converter 50 electrically coupled to the DC-DC converter 40, and an electric motor 60 electrically coupled to the DC-AC converter 50.

[0044] A conventional high-voltage battery pack 30 is typically organized as a series chain of low-voltage battery modules 32 (see, e.g., FIGS. 3A and 3B). Each such module 32 further comprises a series-connected set of individual low-voltage cells 34 and a simple built-in battery management system 36 to regulate basic cell-related characteristics such as state of charge and voltage (see, e.g., FIG. 3B). Electronics with more sophisticated capabilities or some form of smart interconnectivity are lacking. As a result, the ability to regulate the power draw per individual cell 34 in any way is also absent. Some of the major consequences are: (1) the weakest cell inhibits the overall performance of the entire battery pack; (2) failure of any cell or module leads to the need for replacement of the entire pack; (3) battery reliability and safety are significantly reduced; (4) battery life is limited; (5) thermal management is difficult; (6) the pack always operates below maximum capacity; and (7) power surges from regenerative braking cannot be easily stored in the battery.

[0045] Conventional charging circuits or systems, such as that represented by charger 20, are typically implemented in separate, integrated systems. Such charging systems step up power (AC or DC signal) coming from outside the EV, convert it to DC, and deliver it to the battery pack 30. The charging system monitors voltage and current and typically provides a steady, constant delivery. Given the design of the battery and typical charging circuitry, there is little ability to adjust charge flow to the individual battery modules 32 of the battery pack 30 based on cell health, performance characteristics, temperature, etc. Charging cycles are also typically long because the charging system and battery pack 30 and individual modules 32 lack circuitry to enable pulse charging or other techniques that would optimize charge transfer or achievable total charge.

[0046] Conventional control includes a DC-DC conversion stage (see, e.g., DC-DC converter 40) to adjust the voltage level of battery pack 30 to the bus voltage of the EV's electrical system. A motor, such as motor 60, is then driven by a simple two-level multi-phase converter (see, e.g., DC-AC converter 50), which then provides the required AC signal to electric motor 60. Each motor is traditionally controlled by a separate controller, driving the motor in a three-phase design. A dual-motor EV would require two controllers, while an EV using four in-wheel motors would require four individual controllers. Conventional controller designs also lack the ability to drive next-generation motors, such as switched reluctance motors (SRMs), which are characterized by a larger number of magnetic pole pieces. Adaptation would require a high-phase design, making the system more complex and ultimately unable to cope with electrical noise and drive performance, such as high torque ripple and acoustic noise.

[0047] In contrast to the complex power electronics circuitry 10 of a conventional EV, the exemplary embodiment provided herein as illustrated in FIG. 2 replaces the charging system 20, battery management module, DC-DC converter 40, and motor controller 50 with an intelligent or smart modular AC battery pack 130 comprising an interconnected assembly of intelligent or smart battery modules 132 that effectively provides a smart electrical "neural network."

[0048] 3A-3I, a series of schematic diagrams illustrate the simplification of the complex high-voltage power electronics circuitry 10 for a conventional EV shown in FIG. 1 into an intelligent or smart battery pack 130, as shown in FIG. 2, comprising an interconnected assembly of intelligent battery modules 132, according to an exemplary embodiment of the present disclosure. As shown in FIG. 3A, the high-voltage battery pack 30 comprises a series chain of low-voltage battery modules 32, each comprising a series connection of low-voltage battery cells 34 and an integrated battery management and control system 36, as shown in FIG. 3B. The high-voltage DC / AC converter 50 can be divided into multiple low-voltage DC / AC converters 52 connected in series, as shown in FIG. 3C. Each individual low-voltage DC / AC converter 52 can be integrated into an individual battery module to form a smart or intelligent battery module 132, as shown in FIG. 3D. For intermittent storage of braking power inrush, FIG. 3E shows an ultracapacitor 38 integrated into each intelligent battery module 132 (see also, e.g., FIG. 4). As depicted in Figure 3F, a high-voltage intelligent battery pack 130 comprises an interconnected assembly of intelligent battery modules 132. As shown in Figures 3G and 3H, the high-voltage intelligent battery pack 130 effectively eliminates the need for a DC / DC converter 40. As shown in Figures 3H and 31, the high-voltage intelligent battery pack 130, which is effectively an intelligent modular AC battery pack 130, effectively eliminates the need for an AC / DC converter / charger 20.

[0049] (Intelligent Battery Module Architecture) 4 and 5 show a perspective view and a schematic diagram, respectively, of an intelligent battery module 132 with regenerative braking / acceleration capability using supercapacitors (or ultracapacitors). It has three main components: a battery 32 with a BMS 36; a supercapacitor module 38 with a bidirectional DC-DC converter based on MOSFET transistors (MOSFETs) S1 and S2 with a supercapacitor bank CSC and a coupled inductor LC; and an output converter 52 based on a four-quadrant H-bridge topology with four MOSFETs S3-S6. As shown in FIG. 5, the intelligent battery module 132 is coupled to a battery module control system 200 (or local electronic control unit (ECU)) and a master control system 210 (or master ECU).

[0050] (ACi battery pack principle of operation) 6 depicts the topology of a three-phase ACi battery pack (130A, 130B, 130C) connected to a motor 60, with N intelligent battery modules connected in series in each phase. Each intelligent battery module in FIGS. 5 and 6 provides three different voltage outputs, namely +V dc , 0, and -V dc +V dc To obtain -V, switches S3 and S6 are turned on, while -V dccan be obtained by turning on switches S4 and S5. By turning on S3 and S5 or S4 and S6, the output voltage becomes 0. The AC outputs of the different output converter levels are connected in series so that the combined voltage waveform is the sum of the inverter outputs. The number m of output phase voltage levels in the ACi battery pack is defined by m = 2s + 1, where s is the number of intelligent battery modules. An example phase voltage waveform for a pulse-width modulation (PWM) modulated 13-level ACi battery pack with six intelligent battery modules connected in series in each phase is presented in FIG. 7B, and the output voltage of one of the intelligent battery modules 132 is shown in FIG. 7A.

[0051] The ACi battery pack can also act as a rectifier / charger for the battery of the intelligent battery module 132 while the vehicle is connected to an AC supply as shown in FIG.

[0052] The switching signals S3÷S6 (see FIGS. 5 and 6) for the switches S3÷S6 of the output converter 152 in each intelligent battery module 132 can be generated in different ways, depending on the flexibility and requirements of the control hardware employed. One approach is to use space vector modulation or sinusoidal PWM to generate a reference voltage for each phase of the intelligent battery module 132. The switching signals for each output converter of the intelligent battery module can then be generated using a phase-shifted carrier technique. This technique ensures that the cells are continuously rotated and that power is equally distributed between them.

[0053] (Modulation of output voltage in ACi battery packs - multi-level PWM modulation) The principle of the phase shift technique is to generate multilevel output PWM using incrementally shifted two-level waveforms. Thus, an N-level PWM waveform is generated by the summation of N-1 two-level PWM waveforms. These two-level waveforms are generated by comparing a reference waveform with a triangular carrier that is incrementally shifted by 360° / (N-1). A nine-level example is shown in FIG. 8A. The carrier is incrementally shifted by 360° / (9-1)=45° and compared to the reference waveform. The resulting two-level PWM waveform is shown in FIG. 8C. These two-level waveforms can be used as gate signals for the output converter (H-bridge) MOSFETs in each intelligent battery module. For our nine-level example with four H-bridges, the 0° signal is used for S3, the 180° signal is used for S6 of the first module, the 45° signal is used for S3, the 225° signal is used for S6 of the second module, and so on. Note that in all H-bridges, the signal for S4 is the complement of S3, and the signal for S5 is the complement of S6, with some dead time to avoid shoot-through of each leg.

[0054] Depending on the resources and limitations of the hardware used to implement the modulation, an alternative is to generate a negative reference signal along with the first (N-1) / 2 carriers. A 9-level example is shown in Figure 8B. In this case, a 0° to 135° PWM signal is generated by V ref The 180° to 315° PWM signal is generated by comparing the -V ref is generated by comparing the carrier from 0° to 135°. However, the logic of the comparison in the latter case must be reversed.

[0055] Other techniques, such as a state machine decoder, may also be used to generate the gate signals for the H-bridge.

[0056] (Modulation of output voltage in ACi battery packs - multi-level hysteresis control) Another approach to generating the switching signals S3 / S6 (see Figures 5 and 6) for the switches of the output converters in each intelligent battery module is the multi-level hysteresis control technique. This control method can be used with any type of motor and is particularly effective for switched reluctance motor (SRM) drives.

[0057] Multi-level hysteresis control is described here for only one of the three phases of a three-phase ACi battery pack. For PMSM motors, three controllers need to be used with an additional circulating current reduction block (not described here). For SRM motors, the number of controllers can exceed three, eliminating the need for a circulating current reduction block.

[0058] For a 9-level ACi battery pack (see FIG. 6) with four intelligent battery modules 132 connected in series in each phase, all possible switching states for the switches of the output converter with the corresponding output voltage levels are presented in Table 1. N and S5 N , N=1, 2, 3, 4 is the number of intelligent battery modules) are presented in this table. F N To avoid shorting the H-bridge converter, only one switch in the half-bridge of the output H-bridge converter can be on (conduction mode) at any instant. Therefore, the even switching element (MOSFET S4 N and S6 N , N=1, 2, 3, 4 is the number of intelligent battery modules) can be easily obtained by reversing the state of the odd switching elements of the same half-bridge. For example, S3 N =1 and S5 N If =0, S4 N =0 and S6 N =1. [Table 1-1] [Table 1-2]

[0059] A zero output voltage of 0VDC can be ensured when all cells are simultaneously operating in a zero state. This can be obtained by bypassing the battery by switching on either both upper switches or both lower switches. For example, for the intelligent battery module 1, S3 1 =1, S5 1 =1, S4 1 =0, S6 1 =0, or S3 1 =0, S5 1 =0, S4 1 =1, S6 1 =1.

[0060] Both voltage levels -3VDC and +3VDC can be obtained using four different combinations, namely ±3VDC1, ±3VDC2, ±3VDC3, and ±3VDC4, where the last index corresponds to the number of intelligent battery modules that operate in the zero state and provide an output zero voltage. Thus, each zero state can be coded using two of the above-mentioned combinations of switching. Therefore, there are eight possible combinations of setting the ±3VDC output voltage level.

[0061] Similarly, the voltage levels -2VDC and +2VDC can both be set by five different combinations, namely ±2VDC 12, ±2VDC 13, ±2VDC 14, ±2VDC 23, ±2VDC 24, depending on the two intelligent battery modules operating at the zero-state voltage. Considering the double possibility of providing the zero state, the total number of possible combinations for ±2VDC is equal to 10.

[0062] Both voltage levels -1VDC and +1VDC can be obtained using four different combinations: ±1VDC1, ±1VDC2, ±1VDC3, ±1VDC4. The last index corresponds to the number of intelligent battery modules operating at the ±1VDC level. Again, each zero state is obtained twice. Thus, as for the ±3VDC level, there are eight possible combinations that provide ±1VDC output voltage levels.

[0063] Finally, maximum voltage levels of -4 VDC and +4 VDC can be provided at the output of the converter phases when all intelligent battery modules of the same phase are operating simultaneously, so there is only one available combination of switching states for each of these cases. Hysteresis Control Voltage Level Selection

[0064] Above, it was explained how all voltage levels of the 9-level ACi battery pack can be obtained by different switching combinations of the output converters of the four intelligent battery modules 142. However, the most significant task for the multi-level hysteresis controller is to control the current feedback (motor phase) signal I REAL Identification of the appropriate output voltage level at any instant of converter operation based on

[0065] A block diagram of the voltage level selector 300 is presented in Figure 9. The voltage level selector comprises two summation blocks Sum1 301 and Sum2 307, five hysteresis blocks 302, 303, 304, 305, and 306, and one look-up table for voltage level determination. The actual feedback current signal I REAL is the reference current I REF and the difference between them is the current error signal I ERROR is the input to all five hysteresis blocks. Each of these blocks has a different setting for the high (HB) and low (LB) boundary thresholds as presented in Table 2, and ΔI is the preset value for the maximum allowable current error. IERROR When the corresponding high boundary (HB) of the hysteresis block is reached, its output value is set to "1" and I ERROR It stays at this level until it crosses its low boundary (LB). This sets a "0" at the output of the hysteresis block, and the output ERROR It remains at this level until it reaches HB again. Therefore, if the low and high boundaries of the five hysteresis blocks are distributed within the range between -ΔI and +ΔI (as shown in Table 2), the output of Sum2 will be I ERROR 9 is used to determine the required output voltage level based on the sum state value of the hysteresis block (the output of Sum2) and taking into account the sign of the actual (or reference) current derivative di / dt. As discussed below, the sign of di / dt can be determined as positive the instant Sum2 reaches a value of 6, and will be changed to negative 1 when Sum2 equals 1. [Table 2]

[0066] (Switching between voltage levels in 9-level four-quadrant hysteresis control) A detailed description of the key principles of switching between voltage levels in a nine-level four-quadrant hysteretic control technique for one phase of a nine-level ACi battery pack operation is presented below.

[0067] In Figure 10B, the reference current I in the motor phase REF (red trace) and the actual current I REAL (blue trace) is I REF -ΔI and I REF +ΔI and separated from each other by ΔI / 5 (green trace), along with five positive (HB1 ÷ HB5) and five negative (LB1 ÷ LB5) hysteresis boundaries (see also Table 2 and Figure 10A). REAL and I REF Current control error I as the difference between ERROR, and the converter output voltage V OUT are presented in Figures 10(a) and 10(c), respectively.

[0068] V within the considered time window (from 23.06 ms) OUT The initial status of is preset by the control system at +4VDC (VDC=80V). At this voltage level, the current I REAL is rising, I ERROR When the first hysteresis boundary LB1 is reached at point A (level -ΔI / 5 in FIG. 10(a)), the output state of the first hysteresis block is changed from "1" to "0", and therefore the sum at the output of the Sum2 block is reduced by 1 from "6" to "5" (FIG. 9). And according to the table in FIG. 9 for di / dt>0, the voltage V OUT becomes +3VDC.

[0069] From the beginning of the considered time window until time t1 (Fig. 10C), the current I REF has a positive di / dt value, and the hysteresis controller operates with the voltage levels presented in the second column of the look-up table in FIG. 10C (di / dt>0). Starting at t1, the current I REF The di / dt sign of is negative, but the hysteresis controller ERROR The hysteresis controller will remain operating for a positive di / dt until time t2, when it reaches the fifth hysteresis boundary LB5 and Sum2=1. This event will switch the operation of the hysteresis controller to the first column of the table for di / dt<0. In other words, the sign of di / dt can be determined as negative at the moment (t2) when Sum2 reaches a value of "1" (it will be changed to positive when Sum2 equals "6"). This logic is implemented in the di / dt estimator block, which will be presented as explained in the next section of this document.

[0070] V OUT While at its maximum negative level of -4VDC, the current I REALis falling (FIG. 10(b)), and when it reaches point F corresponding to the first hysteresis boundary HB1 in FIG. 10(a), the output state of the first hysteresis block changes from "0" to "1", and therefore the sum at the output of Sum2 is increased by 1 from "1" to "2" (FIG. 9). And according to the look-up table in FIG. 9 for di / dt<0, the voltage V OUT At point G, I REAL and I ERROR When reaches HB2, Sum2 is incremented again and V OUT will be -2VDC.

[0071] In the hysteresis control method provided herein, the maximum current error ΔI is determined by the reference current I REF This occurs only at the time when the di / dt value of ΔI / 5 changes sign. Beyond these critical points, the method reduces the current error I at ΔI / 5 as fast as possible given the load parameters. ERROR Operate in a manner that minimizes

[0072] (Overall method description) A generalized functional diagram of a 9-level four-quadrant hysteretic current controller 500 with state-of-charge balancing and zero-state rotation is presented in FIG. 11. It includes a switching stage selector 300, which functions as previously described. The output signal of Sum2 in FIG. 9 is labeled "Level" in FIG. 11. This signal represents a numeric value (from 1 to 6) for the general level of the 9-level hysteretic controller, which is further used in the present method to select the appropriate output voltage level of the output converter of the intelligent battery module.

[0073] According to the lookup table in Figure 9, knowledge of the di / dt sign is required to select the appropriate output voltage level. As previously mentioned, the di / dt sign can be determined as negative when "Level" reaches a value of "1," and will be changed to positive when "Level" equals "6." This logic is implemented in the di / dt estimator block shown in Figure 13. The estimator block comprises two digital comparators (Comp1 and Comp2) and an RS flip-flop element. Both comparators provide "false"-to-"true" transition pulses at the instants when the "Level" signal equals "6" (Comp1) and "1" (Comp2). These rising edges are detected by the RS flip-flop, which changes its output state accordingly and provides a "true" signal at its non-inverting output Q when di / dt > 0 and a "false" signal when di / dt < 0.

[0074] As previously mentioned and presented in Table 1, there are many switching states available for each voltage level of a 9-level ACi battery pack, excluding ±4 VDC, when all intelligent battery modules are involved in providing the maximum positive or negative output voltage. Therefore, considering that the hysteresis "level" and the sign of di / dt are known parameters, there are the following main tasks that must be solved to control the motor current: 1) Identifying intelligent battery modules that need to be repeatedly switched over over a period of time to provide the required output voltage level and output current adjustment based on the state of charge (SOC) of each intelligent battery module. This identification methodology is required to ensure state-of-charge balance during operation of the ACi battery pack. When this is provided, the energy stored in the battery or transferred from or to the motor is equally distributed among all intelligent battery modules. This is a necessary condition for the correct operation of the ACi battery pack, where each cell needs to be designed for a specific temperature profile of the semiconductor switches based on their operating regime. This task is performed by the SOC balancing block (see FIG. 11) in the method provided herein, and a functional diagram of the intelligent battery module rotation controller 600 as a main component of this block is presented in FIG. 12. 2) Rotation of the zero switching state for the intelligent battery module identified by the SOC balancing block. This rotation provides a distribution of energy among the switches within the specific module during operation. As shown in Table 1, there are two possible combinations of switches to provide zero voltage at the output of the intelligent battery module. The rotation methodology alternates the switches used to provide zero voltage with every other positive or negative operating level of the cells. In fact, as will be shown in the next section of this document, this rotation reduces the switching frequency of the switches by a factor of two compared to the output voltage frequency of the intelligent battery module and the entire ACi battery pack. For different levels of output voltage from 0 VDC to 3 VDC, as shown in Figures 16A, 16B, 16C, and 16D, in the method provided herein, there are four rotation generator blocks 1001, 1002, 1003, and 1004.

[0075] Each of the four rotation generators in Figures 16A, 16B, 16C, and 16D includes four digital comparators, one inverting element, four logical AND elements, two SR flip-flops (Latch 1 and Latch 2), and two dividers by two. The structure and operation principle of all rotation generator blocks are identical; the only difference lies in the preset values ​​of the digital comparators. In the 0VDC rotation generator, when the "di / dt" signal from the di / dt estimator output is "true," comparator Comp1 will set the SR flip-flop Latch 1 output to "true" when the "Level" signal is equal to "3," corresponding to an output voltage level of +1VDC. Another comparator Comp2, in a positive di / dt state, will reset Latch 2 when the "Level" signal is equal to "2," corresponding to an output voltage level of +0VDC. In other words, a high-level pulse train at the output of Latch 1 would correspond to a +1 VDC voltage at the output of the 9-level converter, while its zero level would indicate a +0 VDC voltage level (+0 indicates that a 0 VDC level follows and / or precedes the +VDC level). Finally, the circuit includes a divider block, and a logic element AND is intended to set the output signal Rot+0 VDC to "true," with a high level of Latch 1 output occurring at a +1 VDC output voltage level and maintaining this "true" signal until a second transition from +0 VDC to +1 VDC occurs. Such an output signal Rot+0 VDC is used to alternate between two possible zero-state switching combinations for the intelligent battery module during operation to provide a +1 VDC voltage level. The same operating logic is behind the Rot-0 VDC signal, generated by the same 0 VDC rotation generator, to alternate between two zero-state switching combinations for the intelligent battery module during operation to provide a -1 VDC voltage level.

[0076] The intelligent battery module rotation controller 600 and the SOC balancing block provided in this specification for the multi-level hysteresis controller are further described. A detailed functional diagram of the intelligent battery module rotation controller is presented in FIG. 12. The input to this block is the measured state of charge SOC1, SOC2, SOC3, and SOC4 from the battery management systems (BMS) of all four intelligent battery modules within one phase. The output signals are distributed as follows: the maximum state of charge SOCmax, the minimum state of charge SOCmin, and then the number of intelligent battery modules (from 1 to 4) with SOCrot3 and SOCrot4, such that SOCmin < SOCrot4 < SOCrot3 < SOCmax. First, SOC1 and SOC2 are compared with each other, and if their difference ΔSOC 12 is higher or lower than the positive or negative threshold of the hysteresis block Hyst1, the output of this block is set to "1" or "0" respectively; otherwise, the previously set value is maintained at the output. This threshold helps to ignore a certain level of noise within the feedback signal and adjust the frequency at which the rotation of the intelligent battery module should occur. Based on the Hyst1 output signal, switch 1 selects the number of intelligent battery modules (1 or 2) with the higher SOC, and switch 5 passes the corresponding SOC value to Sum3, which compares it with the minimum state of charge of SOC3 and SOC4 through the same comparison technique. Thus, at the output of the intelligent battery module rotation controller, the intelligent battery module numbers are distributed according to their SOCs as SOCmin < SOCrot4 < SOCrot3 < SOCmax. Before proceeding to the rotation block, the signals SOCmax and SOCmin are reassigned to SOCrot1 and SOCrot2 within the SOC balancing block (see FIG. 11), taking into account the sign of the reference current I REF Current I REFis positive, corresponding to the transfer of energy from the intelligent battery module to the motor, the intelligent battery module with the maximum SOC will participate in the rotation of all positive output voltage levels (although not simultaneously). This will cause a faster discharge of the intelligent battery module with the maximum SOC, since at a positive output voltage and positive load current there is only one way for energy to be transferred from the intelligent battery module to the motor. At the same time, the positive output current (or I REF ), the intelligent battery module with the minimum SOC is responsible for providing only the negative output voltage level and needs to charge its battery voltage as quickly as possible, since with a positive load current but a negative output voltage of the output converter, there is only one direction for energy transfer from the motor to the battery.

[0077] The 0VDC rotation and 1VDC rotation blocks are shown in Figures 14A, 14B, 15A, and 15B, respectively. First, we will explain +0VDC rotation. This block receives one control signal from the intelligent battery module balancing block SOCrot1 and one signal, Rot+0VDC, from the 0VDC rotation generator. It provides control signals for the switching elements of the 9-level ACi battery pack for a +0VDC output voltage, where +0 means that the 0VDC level follows and / or precedes the +VDC level. Multiplexer Switch1 selects one of four different combinations of switching signals based on the input signal SOCrot1, which indicates the intelligent battery modules simultaneously operating to provide the +VDC output level. This means that a zero switching state rotation needs to be implemented for this specific intelligent battery module (with the SOCrot1 number). The input signal Rot+0VDC controls the switching sequence between two possible zero states

[11] and

[00] for the same intelligent battery module.

[0078] The +1VDC Rotation block has a more complex structure. In addition to the control signal Rot+1VDC coming from the 1VDC Rotation Generator block, it receives two control signals SOCrot1 and SOCrot3 from the SOC Balancing block. The first signal SOC1rot is used by the multiplexer switch 1 to set the positive voltage at the output of the intelligent battery module whose number is determined by this signal. This is done by providing a switching combination

[10] for that intelligent battery module. All other three intelligent battery modules must provide a zero switching state. If the voltage at the converter output varies between +0VDC and +1VDC, the signal Rot+1VDC is always "true" and there is no zero switching state rotation for the other three cells. If the output voltage varies between +1VDC and +2VDC, a zero state rotation needs to be implemented for only one specific intelligent battery module involved in generating the +2VDC level. The input signal Rot+1VDC controls the sequence of switching between the two possible zero states

[11] and

[00] for the intelligent battery module.

[0079] The same operating principle is valid for -0VDC and -1VDC rotation, with the only differences being input signal SOCrot2 instead of SOCrot1 and Rot-1VDC instead of Rot+1VDC. The SOCrot3 signal, which indicates the number of cells operating at both +2DC and -2VDC levels, remains the same for the positive rotation block.

[0080] The blocks +2VDC Rotation and +3VDC Rotation have a complex structure with four input signals, three of which, namely SOCrot1, SOCrot2 and SOCrot3, originate from the SOC balancing block and one signal either from the 2VDC Rotation Generator or the 3VDC Rotation Generator intended to control the sequence of changes between zero switching states for a specific intelligent battery module.

[0081] A detailed discussion of multi-level hysteresis control is provided in U.S. Provisional Application No. 62 / 518,331, filed June 12, 2017, and U.S. Provisional Application No. 62 / 521,227, filed June 16, 2017, which applications are incorporated by reference as if fully set forth.

[0082] (Local and Master ECU functions) The power electronics converter and local ECU 200, which manages the intelligent battery module 132 operation (see FIG. 5), operates through the use of a state-of-charge (SOC) estimator to measure the initial SOC of the battery. A master control system (ECU) 210 receives this initial SOC data of all intelligent battery modules and sorts them, as depicted in FIG. 17 (see also FIG. 5).

[0083] The SOC balancing technique for multi-level hysteretic controllers was described above. For multi-level PWM, the balancing methodology is as follows: assuming all batteries are balanced before discharging, when the ACi battery pack is fully charged, the strongest battery is the one with the highest initial SOC and the weakest battery is the one with the lowest initial SOC.

[0084] In response to this data, the master ECU 210 calculates the corresponding switching signal array required for proper operation of each individual intelligent battery module based on its battery capacity. In other words, to balance the state of charge of the modules, the SOC of each module should be compared to the total SOC, which can be calculated as follows: [ka] In the ceremony, SOC i and Q iare the individual SOCs and capacities of the batteries of the i-th intelligent battery module, and the difference may be used to control the modulation index (M) of each module in conjunction with a PI controller. Note that when the modules are charging, the direction of the effect of the SOC difference must be reversed, since in this case the module with the higher SOC is expected to receive less energy compared to the other modules.

[0085] The local control system of the intelligent battery module 132 obtains this information and therefore controls the individual DC currents (I DC1 , I DC2 …I DCN ) and DC bus voltage (battery voltage V B1 , V B2 …V BN ) is determined by the switching signal array S 1…N Thus, the power management works, and the built-in power electronics unit autonomously manages the output power of each intelligent battery module. The strongest battery carries the highest current and the weakest battery carries the least current so that the SOC of all batteries converges at a certain time.

[0086] (Supercapacitor module) The supercapacitor module 38 of the intelligent battery module 132 (FIG. 5) is connected in parallel with the main battery 32 and the output converter 52. During acceleration, the capacitor voltage is allowed to discharge from a full charge (50 Vdc) to about one-third of its nominal voltage (17 Vdc), allowing it to deliver 11 kW of useful energy. This amount of energy allows 2.2 kW of power to be drawn from a single intelligent battery module for 5 seconds, for a total of 66 kW, if 30 intelligent battery modules are installed in an ACi battery pack—enough power and time for good acceleration without damage to battery life. During deceleration (regenerative braking), energy is recovered in a similar manner to recharge the supercapacitor.

[0087] When the vehicle accelerates, the battery delivers the amount of current the motor needs. If this current exceeds the current limit for the battery, the supercapacitor provides the difference. Regenerative braking operation is similar. In this case, the motor acts as a generator delivering recovered energy into the battery, but if the injected current exceeds the limit, a DC-DC converter injects the excess into the supercapacitor.

[0088] The DC-DC converter operates in two ways: boost operation, which is used for acceleration to discharge the supercapacitor, and buck operation, which is used for deceleration (regenerative braking) to discharge the supercapacitor. During boost operation (acceleration), MOSFET S2 is switched on and off at a controlled duty cycle D to transfer the required amount of energy from the capacitor to the battery pack. When S2 is on, energy is taken from the supercapacitor and applied to inductor L C When S2 is switched off, L C The energy stored in C F During buck operation, the converter transfers energy from the battery to the supercapacitor. This is accomplished using controlled operation on S1. When S1 is switched on, energy travels from the battery to the supercapacitor, and L C stores some of this energy. When S1 is switched off, L C The residual energy stored in is transferred inside the supercapacitor through the diode of S2.

[0089] The battery as the primary energy source is the one with the highest energy content and should therefore provide the average power required by the motor, while the supercapacitor is the secondary energy source and assists the battery by providing / absorbing the instantaneous load power peaks.

[0090] The redundant structure of power flow management between the two sources and the motor is depicted in Figure 18. This has advantages over other power control methods, as it allows a complete decoupling between the electrical characteristics of each source (terminal voltage and current) and the electrical characteristics of the load. The power flow controller 1 receives the reference battery power flow P from the local ECU of the intelligent battery module. BATT,REF This signal is used to receive the motor power P iBATTERY Based on the requirements and the SOC of the batteries of the individual intelligent battery modules, which is determined by the main power management controller located in the master ECU, the power flow controller 1 estimates the maximum allowed battery charge / discharge current and determines the actual allowed battery power flow P BATT This signal is calculated as P iBATTERY and the difference between them is the signal P SC,REF is applied to the power flow controller 2 as a supercapacitor voltage V SC Based on I SCM Calculate the current and determine the switching signals S1 and S2 for the buck / boost converter of the supercapacitor module, the basic working principle of which is explained above. iBATTERY The flow is provided by the output converter, P BATT is estimated based on the maximum battery current and the actual SOC, and P iBATTERY and P SC The difference between the two is ensured, and the last one is managed by the converter of the supercapacitor module.

[0091] Another important function performed by the supercapacitor module is to reduce the DC current I of the output converter as a result of the inherent pulsating power nature of single-phase systems. DC Active filtering of secondary current harmonics appearing in V(t) OUT and I(t) OUT Considering that the output voltage and current of the intelligent battery module are: [ka] The instantaneous input / output power balance of the intelligent battery module results in: [ka]

[0092] The first constant term refers to the average power used to charge / discharge the battery. However, the second oscillatory term does not contribute to the average battery SOC. This component has a significant peak-to-peak value that can reach up to twice the grid current amplitude at unity modulation indices. The secondary current component exhibits several disadvantages, such as an increase in the internal battery resistance losses associated with the resulting RMS current value and cyclic changes in battery behavior.

[0093] The main waveforms for the active filtering case are shown in Figures 20A and 20B. The supercapacitor is connected to the battery current I B Before compensation starts (before the moment t1), the battery I B The current is divided into DC components (I B =130A) and amplitude I 2AC = 60 A. Starting from the instant t1, the supercapacitor module SC starts to generate a current I B This current I is redirected to the supercapacitor (see Figure 20B). SC I DC The amplitude of the main harmonic is equal to that of the second harmonic of the current (see FIG. 19), but as shown in FIG. 20A, the battery I B with nearly opposite phase angles in such a way that the resulting current in contains either only a DC component, or mostly a DC component with some significantly reduced AC ripple.

[0094] At high RPM, secondary current harmonics are generated by the filtering capacitor C Fis significantly suppressed by the operation of the supercapacitor module is not required.

[0095] Figure 21 shows a single-phase 9-level four-quadrant intelligent battery pack connected to a single-phase load, presented as an RL load. The system can be used for energy storage and interruptible power supply systems in residential or commercial buildings.

[0096] Figure 22 shows a three-phase intelligent battery pack comprising three nine-level two-quadrant single-phase intelligent battery packs connected to a three-phase switched reluctance motor (SRM). The use of a multi-level hysteretic current controller and intelligent battery packs improves the efficiency and overall performance of the SRM and allows for significant reductions in torque ripple and acoustic noise.

[0097] In the foregoing description, numerous specific details are set forth to provide a thorough understanding of the present embodiments. However, it will be apparent that the present embodiments may be practiced without these specific details. To increase clarity, some well-known circuits, system configurations, and process steps may not be described in detail. In other instances, structures and devices are shown in block diagram form to avoid obscuring the present invention.

[0098] The drawings illustrating embodiments of the present disclosure are semi-schematic and not to scale, in particular some of the dimensions are shown exaggerated in the drawings for clarity of presentation.

[0099] References in the preceding description to "one embodiment," "an embodiment," or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

[0100] Some portions of the detailed description are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps require physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

[0101] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as will be apparent from the disclosure that follows, throughout this disclosure, terms such as "processing," "calculating," "calculating," "determining," "displaying," or the like, should be understood to refer to the actions and processes of a computer system or similar electronic computing device that manipulates and converts data represented as physical (electronic) quantities in the computer system's registers and memory into other data that is similarly represented as physical quantities in the computer system's memory or registers, or other such information storage, transmission, or display device.

[0102] The present embodiments also relate to apparatus for performing the operations herein. The apparatus may be specially constructed for the required purposes, or it may be a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. The present embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment containing both hardware and software elements. In one embodiment, the present embodiments are implemented in software, comprising instructions or data stored on a computer-readable storage medium, including, but not limited to, firmware, resident software, microcode, or another method of storing instructions for execution by a processor.

[0103] Furthermore, the embodiments may take the form of a computer program product accessible from a computer-usable or computer-readable storage medium providing program code for use by or in connection with a computer or any instruction execution system. For purposes of this description, a computer-usable or computer-readable storage medium is any apparatus that may contain, store, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium may be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device), or a propagation medium. Examples of tangible computer-readable storage media include, but are not limited to, semiconductor or solid-state memory, magnetic tape, removable computer diskettes, random access memory (RAM), read-only memory (ROM), rigid magnetic disks, optical disks, EPROMs, EEPROMs, magnetic or optical cards, or any type of computer-readable storage medium suitable for storing electronic instructions, each coupled to a computer system bus. Examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read / write (CD-R / W), and digital video disk (DVD).

[0104] To the extent that embodiments disclosed herein include or operate in conjunction with memory, storage, and / or computer-readable medium, that memory, storage, and / or computer-readable medium is non-transitory. Thus, to the extent that memory, storage, and / or computer-readable medium is covered by one or more claims, that memory, storage, and / or computer-readable medium is only non-transitory. The terms "non-transitory" and "tangible" as used herein are intended to describe memory, storage, and / or computer-readable medium that exclude propagating electromagnetic signals, but are not intended to limit the type of memory, storage, and / or computer-readable medium in terms of persistence of storage or otherwise. For example, "non-transitory" and / or "tangible" memory, storage, and / or computer-readable media encompasses volatile and non-volatile media, such as random-access media (e.g., RAM, SRAM, DRAM, FRAM, etc.), read-only media (e.g., ROM, PROM, EPROM, EEPROM, Flash, etc.), and combinations thereof (e.g., hybrid RAM and ROM, NVRAM, etc.), and later-developed variants thereof.

[0105] A data processing system suitable for storing and / or executing program code includes at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements may include local memory employed during the actual execution of the program code, mass storage devices, and cache memory that provides temporary storage of at least some program code to reduce the number of times the code must be read from mass storage devices during execution. In some embodiments, input / output (I / O) devices (such as keyboards, displays, pointing devices, or other devices configured to receive data or present data) are coupled to the system either directly or through intervening I / O controllers.

[0106] Network adapters may also be coupled to the data processing system to enable coupling to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modems, and Ethernet cards are just some examples of currently available types of network adapters.

[0107] Finally, the methods and displays presented herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may be used in conjunction with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the required method steps. The required structure for a variety of these systems will appear from the description below. It will be understood that a variety of programming languages ​​may be used to implement the teachings of the invention as described herein.

[0108] The figures and detailed description describe certain embodiments, by way of example only. Those skilled in the art will recognize from the foregoing description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles described herein. Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying figures. It should be noted that, where practical, like or similar reference numerals may be used in the figures to indicate like or similar functionality.

[0109] Embodiments of the present disclosure are directed to a converter battery module architecture for an intelligent battery (iBattery) module used as a building block of an intelligent battery pack or system of intelligent battery packs. In embodiments, the iBattery module comprises a battery unit, a supercapacitor or ultracapacitor module unit, and an output converter unit. In embodiments, the iBattery module's local control unit is configured to accept, process, and transmit signals, including but not limited to, from the iBattery module's temperature, voltage, and current sensors and the like, trigger and fault signals to and from semiconductor switches, and voltages of the battery unit's base cells and supercapacitor modules. In embodiments, the local control system facilitates communication with, and transmission of corresponding control signals to and from, a master control unit of an intelligent alternating current battery pack (ACi-battery pack) comprising multiple iBattery modules.

[0110] Embodiments of the present disclosure are directed to an Alternating Current (ACi-battery pack) comprising two or more iBattery modules interconnected together in each phase. In embodiments, an output voltage of any shape and frequency can be generated at the output of the ACi-battery pack as a superposition of the output voltages of the individual iBattery modules.

[0111] Embodiments of the present disclosure are directed to a method of multi-level current hysteresis control for controlling an ACi-battery pack and providing balance between the SOC and the iBatteries in the ACi-battery pack. In embodiments, the method enables power sharing among all iBattery modules in the ACi-battery pack. In embodiments, power sharing among all iBattery modules can be used to keep the SOC of the iBattery's battery modules balanced at all times during operation, ensuring that the full capacity of each module is utilized regardless of possible differences in capacity.

[0112] Embodiments of the present disclosure are directed to processes, methodologies, and systems described herein relating to motor vehicles and stationary energy storage systems.

[0113] Embodiments of the present disclosure are directed to an electric vehicle having a chassis, three or more wheels operably coupled to the chassis, one or more electric motors operably coupled to the three or more wheels, one or more intelligent modular battery packs operably coupled to the one or more motors, and a control system operably coupled to the one or more battery packs and the one or more motors.

[0114] In an embodiment, the chassis is drivetrain-less. In an embodiment, the one or more motors are in-wheel motors.

[0115] In an embodiment, the one or more intelligent modular battery packs have a cascaded architecture.

[0116] In an embodiment, a battery pack comprises a plurality of interconnected intelligent battery modules.

[0117] In an embodiment, a battery module comprises an integrated combination of a networked low-voltage converter / controller with peer-to-peer communication capabilities, an embedded ultracapacitor or supercapacitor, a battery management system, and a series-connected set of individual cells.

[0118] In an embodiment, the battery pack comprises a neural network comprising a plurality of interconnected intelligent battery modules.

[0119] In an embodiment, the battery module comprises an integrated combination of a battery with a BMS, a supercapacitor module, and an output converter.

[0120] In an embodiment, the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank.

[0121] In an embodiment, the output converter comprises a four-quadrant H-bridge.

[0122] In an embodiment, the control system comprises a bidirectional multi-level controller.

[0123] In an embodiment, the bidirectional multilevel controller is a bidirectional multilevel hysteretic controller.

[0124] In an embodiment, a bidirectional multi-level controller is combined with a temperature sensor and networking interface logic.

[0125] In an embodiment, the control system is configured to balance battery utilization through individual switching of modules based on module age, thermal conditions, and performance characteristics.

[0126] In an embodiment, the battery pack is switchable into rectifier / charger operation.

[0127] Embodiments of the present disclosure are directed to an intelligent modular battery pack comprising a cascaded architecture comprising multiple interconnected intelligent battery modules.

[0128] In an embodiment, the battery module comprises an integrated combination of a networked low-voltage converter / controller with peer-to-peer communication capabilities, an embedded ultracapacitor, a battery management system, and a series-connected set of individual cells.

[0129] In an embodiment, the interconnected intelligent battery modules comprise a neural network.

[0130] In an embodiment, the battery module comprises an integrated combination of a battery with a BMS, a supercapacitor module, and an output converter.

[0131] In an embodiment, the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank.

[0132] In an embodiment, the output converter comprises a four-quadrant H-bridge.

[0133] Embodiments of the present disclosure are directed to an intelligent battery module comprising an integrated low-voltage converter / controller with peer-to-peer communication capabilities, a built-in ultracapacitor, a battery management system, and multiple series-connected sets of individual cells.

[0134] Embodiments of the present disclosure are directed to an intelligent battery module comprising a battery with an integrated BMS, a supercapacitor module operably coupled to the battery, and an output converter operably coupled to the battery and the supercapacitor module.

[0135] In an embodiment, the supercapacitor module includes a bidirectional DC-DC converter and a supercapacitor bank.

[0136] In an embodiment, the output converter comprises a four-quadrant H-bridge.

[0137] All features, elements, components, functions, and steps described with respect to any embodiment provided herein are intended to be freely combinable and substituted with those from any other embodiment. If a feature, element, component, function, or step is described with respect to only one embodiment, it should be understood that that feature, element, component, function, or step can be used in conjunction with all other embodiments described herein unless expressly stated otherwise. This paragraph therefore serves as a prior basis and written support for the introduction of claims that, from time to time, combine features, elements, components, functions, and steps from different embodiments or substitute features, elements, components, functions, and steps from one embodiment with those of another embodiment, even if the following description does not explicitly state that such combinations or substitutions are possible in a particular instance. An explicit description of all possible combinations and substitutions would be unduly burdensome, especially given that the permissibility of any and all such combinations and substitutions would be readily apparent to those of ordinary skill in the art upon perusal of this description.

[0138] In many instances, entities are described herein as being coupled to other entities. It should be understood that the terms "coupled" and "connected," or any of their forms, are used interchangeably herein and are general in both cases to the direct coupling of two entities without any significant, e.g., parasitic, intervening entities, and the indirect coupling of two entities with one or more significant intervening entities. When entities are shown as being directly coupled together or described as being coupled together without description of any intervening entities, it should be understood that those entities may also be indirectly coupled together, unless the context clearly dictates otherwise.

[0139] While the embodiments are susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are described in detail herein. It should be understood, however, that these embodiments are not limited to the particular forms disclosed; on the contrary, these embodiments are intended to cover all modifications, equivalents, and alternatives falling within the spirit of the disclosure. Furthermore, negative limitations may be set forth in or added to the claims that define the scope of the claimed invention by any feature, function, step, or element of the embodiments and any feature, function, step, or element that does not fall within its scope.

Claims

1. A modular battery pack system controllable to supply power to a motor load of an electric vehicle (EV), the modular battery pack system comprising: a plurality of converter modules arranged in at least three units, each unit comprising at least two converter modules coupled together to output a single-phase AC voltage signal, the single-phase AC voltage signal comprising a superposition of pulse-width modulated (PWM) output voltages from each of the at least two converter modules, the at least three units together outputting an AC voltage signal of at least three different phases, each converter module of the plurality of converter modules comprising: a primary energy source coupled between a first node and a second node, the primary energy source being a battery, and a voltage between the first node and the second node being V DC ; a switch circuit comprising a plurality of switches controllable to selectively output one of three voltages output from the converter module, the three voltages being +V DC , zero, and −V DC ; a local control device configured to output switch signals to the plurality of switches based on control information, and configured to receive state-of-charge (SOC) information for the battery and output the state-of-charge (SOC), wherein outputting the switch signals includes selecting one switching signal array from a plurality of switching signal arrays, the selection being based on the control information, and each switching signal array comprising a combination of switching signals; a plurality of converter modules, each comprising: a master control device configured to balance utilization of each battery across the plurality of converter modules by receiving and using the SOC information received from each local control device of each of the plurality of converter modules of each of the at least three units and outputting the control information to each of the local control devices, the control information for each local control device of each of the plurality of converter modules being generated based on comparing the SOC received from the local control device to a total state of charge determined from the SOC information received from each local control device of the plurality of converter modules; A modular battery pack system comprising:

2. A modular battery pack system as described in claim 1, wherein each battery comprises a series connection of battery cells.

3. The modular battery pack system of claim 1, further comprising a secondary energy source coupled between the inductor and the second node, each secondary energy source being a supercapacitor or an ultracapacitor.

4. A modular battery pack system as described in claim 1, wherein each switch of the first plurality of switches is a transistor with a diode in parallel.

5. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to supply power from the secondary energy source to assist the battery in providing power during acceleration of the EV.

6. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to charge the battery during regenerative braking of the EV.

7. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to charge the secondary energy source during regenerative braking of the EV.

8. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to inject excess current to charge the secondary energy source when charging current generated during regenerative braking of the EV exceeds battery limits.

9. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to actively filter second harmonics in the current from the battery using current from the secondary energy source.

10. A modular battery pack system as described in claim 1, wherein the master control device is configured to generate control information comprising a switch signal and output the control information to each of the local control devices.

11. A modular battery pack system as described in claim 1, wherein for each converter module of the plurality of converter modules, the local control device is configured to generate and output a switch signal for the first plurality of switches.

12. The modular battery pack system of claim 1, wherein the modular battery pack system further comprises temperature, voltage, and current sensors, and the local control device is configured to process signals from the temperature, voltage, and current sensors of the modular battery pack system.

13. Each unit comprises S converter modules, where S is 2 or more, and the system comprises: generating, for each unit, at least one reference waveform signal and at least S carrier signals, each of the at least S carrier signals having a different phase; For each unit, generating at least 2S pulse width modulated (PWM) switching signals by using the at least one reference waveform signal and the at least S carrier signals; controlling the second plurality of switches of the S converter modules of each unit using the PWM switching signal so that each unit outputs the single-phase AC voltage signal comprising a superposition of output voltages from each of the S converter modules of the unit; 10. The modular battery pack system of claim 1, configured to:

14. A modular battery pack system controllable to supply power to a motor load of an electric vehicle (EV), the modular battery pack system comprising: a plurality of converter modules arranged in at least three units, each unit comprising at least two converter modules coupled together to output a single-phase AC voltage signal, the single-phase AC voltage signal comprising a superposition of pulse-width modulated (PWM) output voltages from each of the at least two converter modules, the at least three units together outputting an AC voltage signal of at least three different phases, each converter module of the plurality of converter modules comprising: a primary energy source coupled between the first node and the second node, the primary energy source being a battery; a secondary energy source coupled between the inductor and the second node; a switch circuit comprising: a first plurality of switches controllable to selectively couple the secondary energy source to either the first node or the second node through the inductor; and a second plurality of switches controllable to selectively output three voltages output from the converter module, the switch circuit being controllable to supply power from the secondary energy source to assist the battery in providing power during acceleration of the EV, or to charge the battery and the secondary energy source during regenerative braking of the EV; a capacitor coupled between the first node and the second node and adapted to receive and store energy from the inductor; a local control device configured to output switch signals to the first and second plurality of switches based on control information, and configured to receive state-of-charge (SOC) information and output information about the battery, wherein outputting switch signals includes selecting one switching signal array from a plurality of switching signal arrays, the selection being based on the control information, and each switching signal array comprising a combination of switching signals; a plurality of converter modules, each comprising: a master control device configured to receive and use the SoC information received from each local control device of each of the plurality of converter modules of each of the at least three units to generate control information and output the control information to each of the local control devices, thereby balancing utilization of each battery across the plurality of converter modules, wherein the control information for each local control device of each of the plurality of converter modules is generated based on comparing the SOC information received from the local control device to a total state of charge determined from the SOC information received from each local control device of the plurality of converter modules; A modular battery pack system comprising:

15. The modular battery pack system of claim 14, wherein each battery comprises a series connection of battery cells.

16. A modular battery pack system as described in claim 14, wherein each secondary energy source is a supercapacitor or an ultracapacitor.

17. The modular battery pack system of claim 14, wherein each switch of the first plurality of switches is a transistor with a diode in parallel.

18. A modular battery pack system as described in claim 14, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to inject excess current to charge the secondary energy source when charging current generated during regenerative braking of the EV exceeds battery limits.

19. A modular battery pack system as described in claim 14, wherein for each converter module of the plurality of converter modules, the switch circuit is controllable to actively filter second harmonics in the current from the battery using current from the secondary energy source.

20. A modular battery pack system as described in claim 14, wherein the master control device is configured to generate control information comprising a switch signal and output the control information to each of the local control devices.

21. A modular battery pack system as described in claim 14, wherein for each converter module of the plurality of converter modules, the local control device is configured to generate and output a switch signal for the first plurality of switches.

22. The modular battery pack system of claim 14, wherein the modular battery pack system further comprises temperature, voltage, and current sensors, and the local control device is configured to process signals from the temperature, voltage, and current sensors of the modular battery pack system.

23. Each unit comprises S converter modules, where S is 2 or more, and the modular battery pack system comprises: generating, for each unit, at least one reference waveform signal and at least S carrier signals, each of the at least S carrier signals having a different phase; For each unit, generating at least 2S pulse width modulated (PWM) switching signals by using the at least one reference waveform signal and the at least S carrier signals; controlling the second plurality of switches of the S converter modules of each unit using the PWM switching signal so that each unit outputs the single-phase AC voltage signal comprising a superposition of output voltages from each of the S converter modules of the unit; 15. The modular battery pack system of claim 14 configured to:

24. A method of generating power for a load using a modular battery pack system comprising a plurality of converter modules arranged in at least three units, each unit comprising S converter modules coupled in series, where S is 2 or greater, said at least three units together outputting AC voltage signals of at least three different phases, each converter module comprising a battery and a plurality of switches controllable to selectively output voltages output from said converter modules, said method comprising: sensing an operating parameter for one or more batteries of the plurality of converter modules; generating a plurality of reference waveform signals for each unit, the reference waveform signals comprising a first reference waveform signal Vref and a second reference waveform signal −Vref; generating, for each unit, at least S carrier signals, each of the at least S carrier signals having a different phase; For each unit, generating at least 2S pulse width modulated (PWM) switching signals using the plurality of reference waveform signals and the at least S carrier signals; controlling the switches of the S converter modules of each unit using the PWM switching signal so that each unit outputs a single phase AC voltage signal comprising a superposition of output voltages from each of the S converter modules of that unit; Including, The method wherein controlling the switches of the S converter modules of each unit with the generated PWM switching signals is for balancing utilization of each battery across the converter modules.

25. The method described in claim 24, wherein controlling the multiple switches of the S converter modules of each unit using the PWM switching signal includes controlling the multiple switches of a first converter module of a first unit to selectively output one of three output voltages, the three output voltages being +V, 0, and -V.

26. The method of claim 24, wherein the at least S carrier signals each have a different phase that is separated by 360° / 2S.

27. ​​The method of claim 24, wherein the operating parameters comprise the state of charge (SOC) of the one or more batteries, and wherein control of the multiple switches of the S converter modules of each unit using the generated PWM switching signal is for SOC balancing of each battery across the multiple converter modules.

28. The method of claim 27, further comprising comparing the state of charge (SOC) for the battery to the total state of charge (SOC) for SOC balance.

29. The method of claim 24, wherein the operating parameters comprise the state of charge (SOC) and temperature of the one or more batteries, and wherein control of the multiple switches of the S converter modules of each unit using the generated PWM switching signal is for SOC balancing and thermal management of each battery across the multiple converter modules.

30. The method described in claim 24, wherein generating the PWM switching signal and controlling the multiple switches of the S converter modules of each unit using the generated PWM switching signal maintains balance of the state of charge (SOC) and temperature of each battery across the multiple converter modules.

31. The method of claim 24, further comprising controlling the modulation index of each of the S converter modules of each unit.

32. The method of claim 31, wherein the control of the modulation index of the converter module is based on the state of charge (SOC) and capacity of the battery of the converter module.

33. The method described in claim 24, wherein the battery of each of the plurality of converter modules is a primary energy source, and each of the plurality of converter modules is provided with a secondary energy source.

34. The method of claim 33, further comprising actively filtering second harmonics in the battery output of each converter module using the secondary energy source.

35. The method described in claim 24, wherein the load is a vehicle motor, the battery of each of the plurality of converter modules is a primary energy source, and each of the plurality of converter modules is provided with a secondary energy source.

36. The method of claim 35, further comprising supplying power from each secondary energy source to assist the battery in providing power during acceleration of the vehicle.

37. The method of claim 35, further comprising charging each battery and secondary energy source using regenerative braking current.

38. The method of claim 35, further comprising injecting at least excess charging current into the secondary energy source if the charging current generated during regenerative braking exceeds a battery limit.

39. The method described in claim 35, wherein each secondary energy source is a supercapacitor or an ultracapacitor.

40. The method described in claim 24, wherein the load is an in-wheel motor of a vehicle.

Images