System and method for bridge mode transition and dynamic soft start of DC-DC converter and battery charger

Abstract

A system for a direct current (DC)-DC converter includes a transformer, a bridge driver connected to a primary side of the transformer, and a bridge rectifier connected to a secondary side of the transformer, one or more switches in the bridge driver operatively configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and transitions between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

Description

Technical Field

[0001] Various embodiments of the present disclosure are generally directed to systems and methods for bridge mode transition and dynamic soft start of a DC-DC converter, and a battery charger for an electric vehicle including a DC-DC converter with bridge mode transition and dynamic soft start. Background Art

[0002] In the field of battery chargers, a two-stage layout is generally used to meet the requirements of on-board chargers for motor vehicles. These on-board chargers have high power density, low weight, and small footprint. The configuration layout used by single-phase or three-phase chargers includes an alternating current (AC) to direct current (DC) power factor correction (PFC) converter in stage I and an isolated DC-DC converter in stage II. Battery chargers are configured for specific applications and may not operate at high efficiency for different power requirements.

[0003] The present disclosure is directed to overcoming one or more of the challenges set forth above. Summary of the invention

[0004] In some aspects, the technology described herein relates to a system for a direct current (DC)-DC converter, the system comprising: a transformer; a bridge driver connected to a primary side of the transformer; and a bridge rectifier connected to a secondary side of the transformer, wherein one or more switches in the bridge driver operatively configure the bridge driver to each of a half-bridge driver configuration and a full-bridge driver configuration and transition between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

[0005] In some aspects, the technology described herein relates to a system that also includes a controller configured to control operation of the one or more switches.

[0006] In some aspects, the technology described herein relates to a system wherein the one or more switches include a first bridge driver switch and a second bridge driver switch on a first branch of the bridge driver, and a third bridge driver switch and a fourth bridge driver switch on a second branch of the bridge driver.

[0007] In some aspects, the technology described herein relates to a system wherein the controller is configured to control operation of the one or more switches to configure the bridge driver into a half-bridge driver configuration by controlling the third bridge driver switch to open and controlling the fourth bridge driver switch to close.

[0008] In some aspects, the technology described herein relates to a system, wherein the controller is further configured to control operation of the one or more switches to configure the bridge driver to a half-bridge driver configuration when a sensed voltage of a battery connected to the DC-DC converter is in a low voltage region, to configure the bridge driver to a half-bridge driver configuration or a full-bridge driver configuration when the sensed voltage is in a nominal voltage region, and to configure the bridge driver to a full-bridge driver configuration when the sensed voltage is in a full voltage region.

[0009] In some aspects, the technology described herein relates to a system wherein the controller is further configured to, when the sensed voltage is in the nominal voltage region, check a power demand of the DC-DC converter, and when the power demand is less than a minimum transition threshold, operate the bridge driver in a half-bridge driver configuration, and when the power demand is greater than the minimum transition threshold, operate the bridge driver in a full-bridge driver configuration.

[0010] In some aspects, the technology described herein relates to a system wherein the controller is further configured to ramp a current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate.

[0011] In some aspects, the technology described herein relates to a system wherein the controller is further configured to maintain a fixed duty cycle of the one or more switches and to vary a switching frequency of the one or more switches.

[0012] In some aspects, the technology described herein relates to a system wherein the controller is further configured to vary the switching frequency based on a comparison of a current reference signal and a measured current.

[0013] In some aspects, the technology described herein relates to a system wherein the DC-DC converter has a voltage operating range from about 170V to about 850V at a battery interface connected to the bridge rectifier.

[0014] In some aspects, the technology described herein relates to a system that also includes an alternating current (AC) to direct current (DC) power factor correction (PFC) converter connected to the bridge driver to provide the system as a battery charger.

[0015] In some aspects, the technology described herein relates to a system that also includes: a battery connected to the DC-DC converter of the battery charger, and a motor configured to rotate based on power received from the battery, wherein the system is provided as a vehicle.

[0016] In some aspects, the technology described herein relates to a system wherein the battery charger is configured to: receive input AC power through the PFC converter, convert the AC power into DC power, and provide the DC power to the battery to charge the battery, and receive DC power from the battery through the DC-DC converter, convert the DC power into AC power, and provide the AC power as output AC power through the PFC converter.

[0017] In some aspects, the technology described herein relates to a system wherein the transformer comprises a high frequency transformer disposed in a resonant tank.

[0018] In some aspects, the technology described herein relates to a method of controlling a system including a direct current (DC)-DC converter, the DC-DC converter including a transformer, a bridge driver connected to a primary side of the transformer, and a bridge rectifier connected to a secondary side of the transformer, the method including performing the following operations by a controller: controlling one or more switches in the bridge driver to configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and transitioning between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

[0019] In some aspects, the technology described herein relates to a method wherein the operation further comprises receiving a sensed voltage of a battery connected to the DC-DC converter, and wherein controlling the switch operation comprises controlling the operation of the one or more switches to configure the bridge driver as a half-bridge driver configuration when the sensed voltage is in a low voltage region, to configure the bridge driver as a half-bridge driver configuration or a full-bridge driver configuration when the sensed voltage is in a nominal voltage region, and to configure the bridge driver as a full-bridge driver configuration when the sensed voltage is in a full voltage region.

[0020] In some aspects, the technology described herein relates to a method wherein the operations further include ramping a current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate.

[0021] In some aspects, the technology described herein relates to a method wherein the operations further include maintaining a fixed duty cycle of the one or more switches and varying a switching frequency of the one or more switches.

[0022] In some aspects, the technology described herein relates to a method in which varying the switching frequency of the one or more switches is based on a comparison of a current reference signal and a measured current.

[0023] In some aspects, the technology described herein relates to a non-transitory computer-readable medium storing instructions that, when executed by one or more processors, perform the following operations: controlling one or more switches in a bridge driver of a DC-DC converter to configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and transitioning between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

[0024] Additional objects and advantages of the disclosed embodiments will be set forth in part in the description that follows, will be apparent in part from the description, or may be learned by practicing the disclosed embodiments. The objects and advantages of the disclosed embodiments will be realized and obtained by the elements and combinations particularly pointed out in the appended claims. As will be apparent from the following embodiments, at least some of the disclosed systems and methods have the advantage of being a charger that can operate over a wide range of input voltages and produce a wide range of output voltages. An advantage of at least some of the disclosed systems and methods is a singular resonant topology that can provide seamless transitions between half-bridge and full-bridge operating modes, and vice versa, depending on battery voltage and output power conditions. An advantage of at least some of the disclosed systems and methods is a soft start operation that can be a software solution that ensures smooth startup of the converter and determines the intended operating mode (half-bridge or full-bridge) without the need for any additional hardware circuitry.

[0025] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosed embodiments, as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and, together with the description, serve to explain the principles of the disclosed embodiments.

[0027] Figure 1 Depicted is an exemplary system infrastructure for a battery charger in accordance with one or more implementations.

[0028] Figure 2 Depicted is an exemplary electrical schematic of a battery charger with a DC-DC converter in accordance with one or more embodiments.

[0029] Figure 3 Depicted are implementations of a computer system that can perform the techniques presented herein, according to one or more embodiments.

[0030] Figure 4Depicted is an exemplary electrical schematic of a battery charger with a DC-DC converter operating with a full-bridge driver according to one or more embodiments.

[0031] Figure 5 Depicted is an exemplary electrical schematic of a battery charger having a DC-DC converter operating in half-bridge operation according to one or more embodiments.

[0032] Figure 6 Depicted is an exemplary mode transition diagram for a battery charger with a DC-DC converter according to one or more embodiments.

[0033] Figure 7 Depicted are exemplary mode operation controls for a battery charger with a DC-DC converter according to one or more implementations.

[0034] Figure 8 Depicted is an exemplary voltage operation control of a battery charger with a DC-DC converter according to one or more implementations.

[0035] Fig. 9 A flow chart is depicted of a method of operating a battery charger having a soft-start DC-DC converter in accordance with one or more embodiments.

[0036] Fig.10 A flow chart is depicted of a method of operating a battery charger having a DC-DC converter in accordance with one or more embodiments. DETAILED DESCRIPTION

[0037] The foregoing general description and the following detailed description are exemplary and explanatory only and do not limit the claimed features. As used herein, the terms "comprises," "having," "including," or other variations thereof are intended to encompass non-exclusive inclusions, such that a process, method, article, or device comprising a series of elements includes not only these elements, but may also include other elements that are not explicitly listed or inherent to such processes, methods, articles, or devices. In this disclosure, unless otherwise stated, relative terms (such as "about," "substantially," and "approximately") are used to indicate that the value may vary by ±10%. In this disclosure, unless otherwise stated, any numerical value may include a possible variation of ±10% of the value.

[0038] Various embodiments of the present disclosure are generally directed to systems and methods for bridge mode transition and dynamic soft start of a DC-DC converter, and a battery charger for an electric vehicle including a DC-DC converter with bridge mode transition and dynamic soft start.

[0039] Although the terminology used below is used in conjunction with the detailed description of certain specific examples of the present disclosure, it is intended to be interpreted in the broadest reasonable manner. In fact, certain terms may even be emphasized below; however, any term that is intended to be interpreted in any limiting manner will be publicly and specifically defined in this detailed description section.

[0040] In the field of battery chargers, a two-stage layout is generally used to meet the requirements of on-board chargers for motor vehicles. These on-board chargers have high power density, low weight and small footprint. The configuration layout used in single-phase or three-phase chargers includes an alternating current (AC) to direct current (DC) power factor correction (PFC) converter in stage I and an isolated DC-DC converter in stage II. The automotive industry's transition from 400V to 800V has brought some problems in achieving high efficiency and better power density capabilities. The power level of on-board chargers has increased to 11kW and 22kW, which can be used with any type of grid input power. Charging systems powered by single-phase or three-phase input have difficulty in achieving charging capabilities at lower output battery voltages. Some methods can stabilize the DC link voltage at the PFC converter to a fixed or variable voltage range to help flexible operation at lower battery voltages, but are limited in terms of output voltage range. Resonant-based DC-DC converters are preferred as stage II converters due to their good performance and have been adopted in many charging applications. Some converters may operate at lower voltages, but have higher losses, including switching losses, conduction losses, and stress on the device. The size of magnetic components designed for a wide voltage range can result in bulky components. In addition, the soft-start method used to limit current and achieve proper operating conditions in DC-DC converter operation is very complex and costly.

[0041] According to one or more embodiments, the charger can operate with single-phase or three-phase AC power and can have high efficiency without being limited by output voltage or power. The disclosed method can provide operation of DC-DC converters for different battery voltages. The charger can be designed to support a wide range of HVDC battery voltage ranges, such as 400V and 800V systems and maximum output powers of 11kW and 22kW.

[0042] In order to achieve higher efficiency at lower output voltage, the charger can be operated using the disclosed method. A DC-DC converter with LLC resonant structure can be used. A PFC converter with single-phase or three-phase power supply can be used.

[0043] In the lower HVDC battery voltage region, the full-bridge operation mode may not be able to meet the lower output current condition at the maximum switching frequency. Similarly, in the higher HVDC battery voltage region, the half-bridge operation mode may not be able to meet the higher output current condition at the minimum switching frequency. The charger may have a medium HVDC battery voltage region where both the full-bridge and half-bridge modes meet the full output current range. Therefore, in order to provide the full output current range for the full HVDC battery voltage range, one or more embodiments may include a single resonant topology that combines the half-bridge and full-bridge operation modes.

[0044] The advantage of a single topology is that it can accommodate a wide HVDC battery voltage range without any additional hardware. In addition, one or more embodiments do not require any hardware modifications to combine half-bridge and full-bridge operating modes. From a hardware perspective, a single resonant half-bridge DC-DC converter may be the same as a full-bridge DC-DC resonant converter, and one or more embodiments may provide software control of individual switches in the DC-DC resonant converter. According to one or more embodiments, a single resonant topology may provide a seamless transition between half-bridge and full-bridge operating modes, and vice versa, depending on the HVDC battery voltage and output power conditions.

[0045] The switching bridge on the primary side of the DC-DC converter includes two branches, each branch including two switches. When the converter is in half-bridge mode, the switch of one branch is inactive (remains open and closed, respectively). Therefore, in half-bridge mode, the switches in only one branch are operated alternately with opposite cycles, wherein each switch in the activated branch has an on-off or closed-open duty cycle of 50%.

[0046] When the HVDC battery voltage is in the medium HVDC battery voltage region and the output power demand is above the threshold, the converter can perform a transition from half-bridge to full-bridge mode. During the transition, the unused branch in the half-bridge mode is activated. Therefore, the switches on both branches of the switching bridge can be operated alternately with opposite cycles, with each switch having an on-off or closed-open duty cycle of 50%.

[0047] When the HVDC battery voltage is in the medium HVDC battery voltage region and the output power demand is below the threshold, the converter can perform a transition from full-bridge to half-bridge mode. During the transition, the switches on one branch are deactivated (respectively kept open and closed so that one switch in the deactivated branch maintains a 100% duty cycle and the other switch in the deactivated branch maintains a 0% duty cycle). Therefore, in half-bridge mode, the switches in only one branch are operated alternately with opposite cycles, where each switch in the activated branch has a 50% on-off or closed-open duty cycle. The switch bridge gain in half-bridge mode is half of that in full-bridge mode.

[0048] Therefore, by controlling the operation of the switches in the switching bridge, transition from half-bridge to full-bridge mode and vice versa can be achieved, and the charging capability of the converter can be enhanced based on the output voltage.

[0049] One or more embodiments can utilize variable power to charge lower battery voltages. Even at lower battery voltages, the current can be increased to provide adequate charging time. The disclosed method for mode transition can be used for an 800V battery system. The maximum voltage of the battery pack can be variable. The user can select a threshold based on the power level of the charger.

[0050] One or more embodiments may include a PFC (AC to DC) converter and a DC-DC converter stage. The PFC converter may receive an AC input from the grid and convert the AC power to a DC voltage and charge an intermediate bulk capacitor. The DC-DC converter receives a DC input from a bulk capacitor and converts the DC input to the required HV battery voltage. A soft start operation may be employed at the DC-DC stage to ensure that there are no transients at the bulk capacitor and the HVDC battery.

[0051] According to one or more embodiments, the DC-DC stage of the charger may regulate the HVDC battery voltage and current to a desired set point. The voltage compensator may regulate the HVDC battery voltage to a voltage reference received from the vehicle. The output of the voltage compensator may be a current reference signal. The current compensator may receive the current reference signal from the voltage compensator, compare the current reference signal with the measured HVDC battery charging current, and generate a switching frequency signal for a switch used in the DC-DC converter. The relationship between the switching frequency and the measured HVDC battery charging current may ensure that there are no transients in the HVDC battery.

[0052] At startup, if the HVDC battery charging current demand is the largest, the current compensator can generate a corresponding switching frequency to adjust to the expected current reference as quickly as possible. However, this may generate large transients at the battery, thereby damaging the battery. Therefore, one or more embodiments can smoothly adjust the measured HVDC battery charging current to the reference current.

[0053] Soft-start operation can ensure smooth startup of the converter. Traditionally, soft-start operation is implemented by additional hardware circuits in the DC-DC converter. The analog circuit slowly ramps up the duty cycle of the DC-DC converter switches to achieve smooth startup of the converter. However, the hardware circuit increases the board space, increases the cost, and does not provide flexibility in operation.

[0054] According to one or more embodiments, the soft start operation can be a software solution that ensures a smooth start of the converter and determines the intended operating mode (half-bridge or full-bridge) without any additional hardware circuitry. In addition, digital control loops (such as voltage and current compensators) can also be used for voltage and current regulation.

[0055] According to one or more embodiments, the soft start operation can use the HVDC battery voltage and the HVDC battery charge current reference as inputs. With these two inputs, the algorithm can automatically select the appropriate operating mode between half-bridge or full-bridge and the appropriate switching frequency to regulate the required HVDC battery charge current. The soft start operation can be programmed to have a variable start rate. In addition, the soft start operation can be extended based on the requirements of the charger, battery, or vehicle.

[0056] According to one or more embodiments, the soft start algorithm can check whether the measured HV battery voltage is within the half-bridge or full-bridge operating range and set the PWM configuration accordingly. When the operating mode is determined, the initial switching frequency of the switch can be set to the maximum value, and the soft start current reference (usually a small HV battery charging current value) can be set. Once the PWM configuration is set, the lower limit of the current loop output can begin to ramp down the switching frequency from the maximum value to the minimum value at a predetermined soft start rate.

[0057] According to one or more embodiments, during the switching frequency ramp-down period, the measured HV battery charging current and the soft-start current reference can be continuously compared to ensure that the current is properly regulated. When the measured current is regulated to the soft-start current reference, the current loop limits can be expanded to the maximum and minimum values, and the soft-start current reference can be smoothly ramped up to the actual HV battery charging current demand.

[0058] According to one or more embodiments, the soft start algorithm can also detect whether the current regulation conditions are met as expected and whether the soft start operation ends within a specified time window. This information can be used to perform appropriate diagnostics.

[0059] The battery charger according to the present disclosure can operate with multiple types of AC input power supplies, including single-phase, split-phase / dual-phase / two-phase and three-phase power supplies. The charger can be compatible with a wide range of operations. The algorithm can ensure that the converter operates under a wide range of input voltage changes, thereby generating a wide range of output voltages. An inductor-inductor-capacitor (LLC) converter can be used as a second-stage converter, using the DC link voltage generated from the PFC as the input voltage of the converter. However, the present disclosure is not limited to this.

[0060] A battery charger according to the present disclosure may have higher efficiency without being limited by output voltage or power. An algorithm according to the present disclosure may provide operation of a configurable DC-DC converter for different battery voltages. The input and output layout of the charger may follow automotive standards. A battery charger according to the present disclosure may include a two-stage configuration, including an AC-DC power factor correction converter stage and an isolated DC-DC converter stage. The isolated DC-DC converter may include a full-bridge driver configuration with a resonant tank element to achieve better efficiency. The DC-DC converter may be designed to charge the battery from a minimum voltage to a maximum voltage.

[0061] The battery charger according to the present disclosure can be operated as a battery charger only, or bidirectionally for charging operation or supplying operation. The converter can either receive power from the AC power supply and provide DC power to the battery, or receive power from the battery and provide power as an AC power supply. Vehicle-to-grid (V2G) operation can be achieved using control strategies designed for single-phase, two-phase and three-phase systems. For example, the switches can be any devices such as GTOs, thyristors, or MOSFET / IGBTs with series diodes. These switches can also be mechanical components (such as relays or contactors) if sufficient failure rates and arc conditions during operation are met.

[0062] Figure 1 Depicted is an exemplary system infrastructure for a battery charger with a DC-DC converter in accordance with one or more implementations.

[0063] like Figure 1 As shown, the battery charger 100 may include or be electrically connected to a charging connector 110. The charging connector 110 may provide an electrical connection from an external power source to the battery charger 100 and may be, for example, a Type 1 or Type 2 connector. The charging connector 110 may transfer single-phase, two-phase, or three-phase power.

[0064] The battery charger 100 may include a power factor correction (PFC) converter 120, a DC-DC converter 130, and a controller 300 that receives a signal from an input sensor 150. The battery charger 100 may include a battery 140 or may be electrically connected to the battery 140. The battery charger 100 may be used as an on-board charger in a motor vehicle to transfer power from an external power source to the battery 140 through a charging connector 110, or to transfer power from the battery 140 in the vehicle to a grid operation. The battery charger 100 may be included in a system provided as an electric vehicle including a motor configured to rotate based on power received from the battery 140.

[0065] Figure 2Depicted is an exemplary electrical schematic of a battery charger with a DC-DC converter in accordance with one or more embodiments.

[0066] like Figure 2 As shown, the PFC converter 120 according to the present disclosure may include four switch branches, which can operate under all types of input power supplies and universal input voltages. The four switch branches may be arranged as follows: Phase A includes switches S1a and S2a, Phase B includes switches S1b and S2b, Phase C includes switches S1c and S2c, and the neutral phase includes switches S3 and S4. The input voltage from the connector 110 may be sensed and the PFC converter 120 may be switched to operate in three-phase, two-phase, or single-phase operation.

[0067] The PFC converter 120 may also include switches Sx and Sy, respectively disposed between the A phase and the B phase and between the B phase and the C phase from the connector 110. For example, all switches described in the present disclosure may be any device such as a GTO, a thyristor, or a MOSFET / IGBT with a series diode. These switches may also be mechanical components (e.g., relays or contactors) if sufficient failure rates and arc conditions during operation are met.

[0068] In addition, the PFC converter 120 may include inductors L1a, L2a, and L3a disposed between switches Sx and Sy and switches of phases A, B, and C, respectively, on phases A, B, and C. A capacitor Cpfc may be disposed at the output of the PFC converter 120 as a DC link capacitor, with a voltage Vpfc to the input of the DC-DC converter 130.

[0069] The DC-DC converter 130 may be any suitable converter that operatively isolates the PFC converter 120 from the battery 140. For example, the DC-DC converter 130 may be a Figure 2 The LLC converter shown may alternatively be a CLLLC converter.

[0070] The bidirectional battery charger 100 may be a system including a PFC converter 120. The PFC converter 120 may include a first (e.g., A) phase switch group (e.g., switches S1a and S2a) connected to a first node from the connector 110 to receive power from a first phase (e.g., Vin,a) of a voltage source. The system may include a second (e.g., B) phase switch group (e.g., switches S1b and S2b) connected to a second node from the connector 110 to receive power from a second phase (e.g., Vin,b) of the voltage source. The system may include a third (e.g., C) phase switch group (e.g., switches S1c and S2c) connected to a third node from the connector 110 to receive power from a third phase of the voltage source (e.g., Vin,c). The system may include a neutral phase switch group (e.g., S3 and S4) connected to a fourth node from the connector 110 to connect to a ground terminal of the voltage source.

[0071] The PFC converter 120 may include a first switch (eg, Sx) connected to a first node and a second node, and a second switch (eg, Sy) connected to the second node and a third node.

[0072] The PFC converter 120 may include an input sensor 150 configured to sense a voltage and / or current of each phase of a voltage source. The PFC converter 120 may include a controller 300 configured to determine a phase of the voltage source based on the voltage and / or current sensed from the input sensor 150, and to control operations of the first, second, third, and neutral phase switch groups (e.g., S1a and S2a, S1b and S2b, S1c and S2c, and S3 and S4) and operations of the first and second switches (e.g., (Sx and Sy)) based on the determined phase of the voltage source.

[0073] The DC-DC converter 130 may be connected to the outputs of the first, second, third and neutral phase switch groups. A voltage source may be connected to one or more of the first, second, third and fourth nodes of the PFC converter 120 , and a battery 140 may be connected to the output of the DC-DC converter 130 .

[0074] The control structure can provide a wide range of changes in the PFC DC link voltage to achieve the desired battery voltage. The battery charger 100 can operate bidirectionally. Using control strategies designed for single-phase, two-phase and three-phase systems, vehicle-to-grid (V2G) operation can also be achieved. The PFC converter 14 can be configured to receive DC power from the battery 140 through a DC-DC converter 130, convert the DC power into AC power, and provide AC power through one or more of the first, second, third and fourth nodes. The requested voltage phase may include single-phase, two-phase and three-phase operation. The controller 300 can be designed to have an algorithm so that based on the requested voltage phase, the controller 300 can control the operation of the first, second, third and neutral phase switch groups and the operation of the first switch and the second switch to provide AC power through one or more of the first, second, third and fourth nodes.

[0075] The controller 300 may be designed and / or configured to run an algorithm for controlling the first, second, third, neutral phases and the first and second (e.g., Sx and Sy) switches to provide a desired DC link voltage Vpfc suitable for the DC-DC converter 130 to charge the battery 140. The algorithm may be designed for balanced and unbalanced power supplies to ensure that appropriate PFC operation is provided to charge the battery 140 with reduced voltage and current ripple. The DC link voltage may be variable, for example, from 300V to 900V, to obtain a desired output voltage to the battery 140.

[0076] The controller 300 may be designed and / or configured to run an algorithm for controlling the switches of the DC-DC converter 130 , including the primary side bridge driver switches Tp1 , Tp2 , Tp3 , and Tp4 and the secondary side bridge rectifier switches Hp1 , Hp2 , Hp3 , and Hp4 .

[0077] Figure 3 An implementation of a controller 300 is depicted that can perform the techniques presented herein in accordance with one or more embodiments.

[0078] Any suitable system infrastructure may be established to allow control of the battery charger. Figure 3 The following discussion provides a brief, general description of a suitable computing environment in which the present disclosure may be implemented. In one embodiment, any of the disclosed systems, methods, and / or graphical user interfaces may be implemented by a computer system that is compatible with the present disclosure. Figure 3, or similar computing systems as shown in . Although not required, aspects of the present disclosure are described in the context of computer executable instructions, such as routines executed by a data processing device (e.g., a server computer, a wireless device, and / or a personal computer). Those skilled in the relevant art will appreciate that aspects of the present disclosure can be practiced using other communication, data processing, or computer system configurations, including: Internet appliances, handheld devices (including personal digital assistants ("PDAs")), wearable computers, various cellular or mobile phones (including voice over IP ("VoIP") phones), dumb terminals, media players, gaming devices, virtual reality devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, set-top boxes, network PCs, minicomputers, mainframe computers, and the like. In fact, terms such as "computer," "server," and the like are generally used interchangeably herein to refer to any of the above-mentioned devices and systems, as well as any data processor.

[0079] Aspects of the present disclosure may be embodied in a special-purpose computer and / or data processor that is specifically programmed, configured, and / or constructed to perform one or more computer-executable instructions explained in detail herein. Although aspects of the present disclosure (e.g., certain functions) are described as being performed only on a single device, the present disclosure may also be practiced in a distributed environment, where functions or modules are shared between different processing devices connected through a communication network (e.g., a local area network ("LAN"), a wide area network ("WAN"), and / or the Internet). Similarly, the techniques proposed herein involving multiple devices may be implemented in a single device. In a distributed computing environment, program modules may be located in local and / or remote memory storage devices.

[0080] Aspects of the present disclosure may be stored and / or distributed on non-transitory computer readable media, including magnetic or optical readable computer disks, hardwired or pre-programmed chips (e.g., EEPROM semiconductor chips), nanotechnology memories, biological memories, or other data storage media. Alternatively, computer-implemented instructions, data structures, screen displays, and other data under aspects of the present disclosure may be distributed over the Internet and / or other networks (including wireless networks), distributed over a propagation signal over a propagation medium (e.g., electromagnetic waves, sound waves, etc.) over a period of time, and / or they may be provided over any analog or digital network (packet switching, circuit switching, or other schemes).

[0081] The controller 300 may include a set of instructions that may be executed to cause the controller 300 to perform any one or more of the methods or computer-based functions disclosed herein. The controller 300 may operate as a standalone device, or may be connected to other computer systems or peripheral devices, for example using a network.

[0082] In a networked deployment, the controller 300 can operate as a server or as a client in a server-client user network environment, or as a peer-to-peer computer system in a peer-to-peer (or distributed) network environment. The controller 300 can also be implemented as or incorporated into various devices, such as a personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile device, a palmtop computer, a laptop computer, a desktop computer, a communication device, a wireless phone, a fixed telephone, a control system, a camera, a scanner, a fax machine, a printer, a pager, a personal trust device, a web device, a network router, a switch or a bridge, or any other machine capable of executing a set of instructions (sequential or other), which specify the actions to be taken by the machine. In a specific implementation, the controller 300 can be implemented using an electronic device providing voice, video or data communication. In addition, although the controller 300 is shown as a single system, the term "system" should also be understood to include a collection of any system or subsystem that executes one or more sets of instructions to perform one or more computer functions individually or jointly.

[0083] like Figure 3 As shown, the controller 300 may include a processor 302, such as a central processing unit (CPU), a graphics processing unit (GPU), or both. The processor 302 may be a component in a variety of systems. For example, the processor 302 may be part of a standard computer. The processor 302 may be one or more general-purpose processors, digital signal processors, application-specific integrated circuits, field programmable gate arrays, servers, networks, digital circuits, analog circuits, combinations thereof, or other devices now known or later developed for analyzing and processing data. The processor 302 may implement a software program, such as a manually generated code (i.e., a programmed code).

[0084] The controller 300 may include a memory 304 capable of communicating via a bus 308. The memory 304 may be a main memory, a static memory, or a dynamic memory. The memory 304 may include, but is not limited to, computer-readable storage media, such as various types of volatile and non-volatile storage media, including but not limited to random access memory, read-only memory, programmable read-only memory, electrically programmable read-only memory, electrically erasable read-only memory, flash memory, tape or disk, optical media, etc. In one implementation, the memory 304 includes a cache or random access memory for the processor 302. In an alternative implementation, the memory 304 is separated from the processor 302, such as a cache memory, system memory, or other memory of the processor. The memory 304 may be an external storage device or database for storing data. Examples include a hard drive, a compact disk ("CD"), a digital video disk ("DVD"), a memory card, a memory stick, a floppy disk, a universal serial bus ("USB") memory device, or any other device that stores data in operation. The memory 304 stores instructions executable by the processor 302 in operation. The functions, actions, or tasks shown in the figures or described herein may be performed by the processor 302 executing instructions stored in the memory 304. These functions, actions, or tasks are independent of a particular type of instruction set, storage medium, processor, or processing strategy, and may be performed by software, hardware, integrated circuits, firmware, microcode, etc. operating alone or in combination. Likewise, processing strategies may include multi-processing, multi-tasking, parallel processing, etc.

[0085] As shown, the controller 300 may further include a display 310, such as a liquid crystal display (LCD), an organic light emitting diode (OLED), a flat panel display, a solid state display, a cathode ray tube (CRT), a projector, a printer, or other display devices known now or developed later for outputting determined information. The display 310 may be used as an interface for a user to view the operation of the processor 302, or specifically as an interface with software stored in the memory 304 or the drive unit 306.

[0086] Additionally or alternatively, the controller 300 may include an input device 312 configured to allow a user to interact with any component of the controller 300. The input device 312 may be a numeric keypad, a keyboard, or a cursor control device (e.g., a mouse, a joystick, a touch screen display, a remote control, or any other device that operatively interacts with the controller 300).

[0087] The controller 300 may also or alternatively include a drive unit 306 implemented as a disk or optical drive. The drive unit 306 may include a computer-readable medium 322 in which one or more sets of instructions 324 (e.g., software) may be embedded. In addition, the instructions 324 may embody one or more methods or logic described herein. The instructions 324 may reside in whole or in part within the memory 304 and / or within the processor 302 during execution by the controller 300. The memory 304 and the processor 302 may also include computer-readable media as described above.

[0088] In some systems, the computer-readable medium 322 includes instructions 324 or receives and executes instructions 324 in response to a propagation signal, so that a device connected to the network 370 can transmit voice, video, audio, image, or any other data through the network 370. In addition, the instructions 324 can be sent or received on the network 370 and / or using the bus 308 via the communication port or interface 320. The communication port or interface 320 can be part of the processor 302 or a separate component. The communication port or interface 320 can be created with software or can be a physical connection in hardware. The communication port or interface 320 can be configured to connect to the network 370, external media, display 310, or any other component in the controller 300, or a combination thereof. The connection to the network 370 can be a physical connection, such as a wired Ethernet connection, or can be established wirelessly as described below. Similarly, additional connections to other components of the controller 300 can be physical connections or can be established wirelessly. The network 370 can alternatively be directly connected to the bus 308.

[0089] Although the computer-readable medium 322 is shown as a single medium, the term "computer-readable medium" may include a single medium or multiple media, such as a centralized or distributed database, and / or associated caches and servers storing one or more sets of instructions. The term "computer-readable medium" may also include any medium capable of storing, encoding, or carrying a set of instructions for execution by a processor or causing a computer system to perform any one or more methods or operations disclosed herein. The computer-readable medium 322 may be non-transitory and may be tangible.

[0090] Computer readable medium 322 may include solid state memory, such as a memory card or other package that accommodates one or more non-volatile read-only memories. Computer readable medium 322 may be random access memory or other volatile rewritable memory. Additionally or alternatively, computer readable medium 322 may include magneto-optical or optical media, such as disks or tapes or other storage devices, to capture carrier signals, such as signals transmitted through a transmission medium. Digital file attachments to e-mails or other self-contained information archives or archives may be considered distribution media, i.e., tangible storage media. Therefore, the present disclosure is considered to include any one or more of computer readable media or distribution media and other equivalents and subsequent media in which data or instructions may be stored.

[0091] In alternative implementations, dedicated hardware implementations, such as application specific integrated circuits, programmable logic arrays, and other hardware devices, may be constructed to implement one or more of the methods described herein. Applications that may include various implementations of the device and system may broadly include various electronic and computer systems. One or more implementations described herein may use two or more specific interconnected hardware modules or devices to implement functions, which have associated control and data signals that may be transmitted between or through the modules, or as part of an application specific integrated circuit. Therefore, the present system encompasses software, firmware, and hardware implementations.

[0092] The controller 300 can be connected to a network 370. The network 370 can define one or more networks, including wired or wireless networks. The wireless network can be a cellular telephone network, an 802.11, 802.16, 802.20, or WiMAX network. In addition, such a network can include a public network (e.g., the Internet), a private network (e.g., an intranet), or a combination thereof, and can utilize various existing or later developed network protocols, including but not limited to TCP / IP-based network protocols. The network 370 can include a wide area network (WAN), such as the Internet, a local area network (LAN), a campus network, a metropolitan area network, a direct connection (e.g., through a universal serial bus (USB) port), or any other network that can allow data communication. The network 370 can be configured to connect one computing device to another computing device to enable data communication between devices. The network 370 can generally use any form of machine-readable media to transmit information from one device to another. The network 370 can include a communication method by which information can travel between computing devices. The network 370 can be divided into subnetworks. A subnetwork may allow access to all other components connected thereto, or a subnetwork may restrict access between components. Network 370 may be considered a public or private network connection and may include, for example, a virtual private network or encryption or other security mechanisms employed over the public Internet.

[0093] According to various embodiments of the present disclosure, the methods described herein may be implemented by a software program executable by a computer system. In addition, in an exemplary, non-limiting implementation, the implementation may include distributed processing, component / object distributed processing, and parallel processing. Alternatively, a virtual computer system process may be constructed to implement one or more methods or functions described herein.

[0094] Although this specification describes components and functions that can be implemented with reference to specific standards and protocols in a particular implementation, the present disclosure is not limited to such standards and protocols. For example, standards for Internet and other packet-switched network transmissions (such as TCP / IP, UDP / IP, HTML, HTTP) represent examples of state-of-the-art technology. These standards are regularly replaced by faster, more efficient, and substantially functionally equivalent equivalents. Therefore, replacement standards and protocols that have the same or similar functions as the standards and protocols disclosed herein are considered equivalents thereof.

[0095] It should be understood that in one embodiment, the steps of the method discussed are performed by executing instructions (computer readable code) stored in a storage device by an appropriate processor (or multiple processors) of a processing (i.e., computer) system. It should also be understood that the present disclosure is not limited to any particular implementation or programming technique, and the present disclosure can be implemented using any suitable technique for implementing the functions described herein. The present disclosure is not limited to any particular programming language or operating system.

[0096] Figure 4 An exemplary electrical schematic diagram of a battery charger with a DC-DC converter operating with a full-bridge driver according to one or more embodiments is depicted. Figure 2 The structure of the battery charger 100 is described.

[0097] like Figure 4 As shown, the battery charger 100 can be configured to operate in a full-bridge driver configuration on the primary side of the transformer 240. For the full-bridge driver operation, the switches on the primary side of the transformer 240 can be controlled so that the primary first switch 211, the primary second switch 212, the primary third switch 213, and the primary fourth switch 214 operate to generate a voltage signal.

[0098] like Figure 4 As shown, the battery charger 100 can be configured to operate in a full bridge driver configuration on the primary side of the transformer 240. For example, when the voltage range of the battery 140 is from 650V to 850V, the full voltage region 830 (see Figure 8) using a full-bridge driver operation. However, the present disclosure is not limited thereto. The full-bridge driver operation may be used for any operation of the battery charger 100 as desired, and the full voltage region 830 may range between any appropriate voltage levels.

[0099] Figure 5 An exemplary electrical schematic diagram of a battery charger with a configurable DC-DC converter operating with a half-bridge driver according to one or more embodiments is depicted. Figure 2 The structure of the battery charger 100 is described.

[0100] like Figure 5 As shown, the battery charger 100 can be configured to operate in a half-bridge driver configuration on the primary side of the transformer 240. For the half-bridge driver operation, the switches on the primary side of the transformer 240 can be controlled so that the primary first switch 211 and the primary second switch 212 operate to generate a voltage signal, the primary third switch 213 is open, and the primary fourth switch 214 is closed.

[0101] like Figure 5 As shown, the battery charger 100 can be configured to operate in a half-bridge driver configuration on the primary side of the transformer 240. For example, when the voltage range of the battery 140 is 360V to 450V, the battery charger 100 can be configured to operate in a half-bridge driver configuration on the primary side of the transformer 240. Figure 8 ) using a half-bridge driver operation. However, the present disclosure is not limited thereto. The half-bridge driver operation may be used for any operation of the battery charger 100 as desired, and the low voltage region 810 may be in a range between any appropriate voltage levels.

[0102] Figure 6 An exemplary mode transition diagram 600 of a battery charger with a DC-DC converter is depicted.

[0103] Figure 6 FIG. 2 shows an implementation of the battery charger 100 to charge the battery 140 with variable power. Figure 6 In this case, the current can be increased to provide adequate charging even at lower battery voltages. Figure 6A half-bridge region 610, a half-bridge or full-bridge region 620, and a full-bridge region 630 are depicted. For example, when the battery voltage approaches 350V and the output power is 1kW, the battery charger 100 can be operated in a half-bridge configuration with a switching frequency of 120kHz. For example, when the battery voltage approaches 365V and the output power is 1.1kW, the battery charger 100 can be operated in a half-bridge configuration with a switching frequency of 109kHz. For example, when the battery voltage approaches 400V and the output power is 2kW, the battery charger 100 can be operated in a half-bridge configuration with a switching frequency of 220kHz. For example, when the battery voltage approaches 550V and the output power is 2kW, the battery charger 100 can be operated in a full-bridge configuration with a switching frequency of 200kHz. For example, when the battery voltage approaches 600V and the output power is 2kW, the battery charger 100 can be operated in a half-bridge configuration with a switching frequency of 68kHz. For example, when the battery voltage is close to 650V and the output power is 2kW, the battery charger 100 can be operated in a full-bridge configuration with a switching frequency of 151kHz. For example, when the battery voltage is close to 800V and the output power is 3.6kW, the battery charger 100 can be operated in a full-bridge configuration with a switching frequency of 96.7kHz.

[0104] Figure 7 Depicted are exemplary mode operation controls for a battery charger with a DC-DC converter according to one or more implementations.

[0105] Method 700 may control a system including DC-DC converter 130 and may include various operations of method 700 being performed by controller 300. Operation 705 may include observing one or more of a voltage of battery 140, an input grid voltage, a DC link voltage, a power requirement, and a state of charge (SOC) of battery 140. Operation 710 may include comparing the voltage of battery 140 to a first reference voltage (e.g., Figure 8 360V as shown) and a second reference voltage (e.g., Figure 8 When the voltage of the battery 140 is greater than the first reference voltage and less than the second reference voltage (yes in operation 710), operation 715 may include controlling the operation of the bridge driver 210 to operate in a half-bridge driver configuration.

[0106] When the voltage of the battery 140 is greater than the second reference voltage (No in operation 710), operation 720 may include comparing the voltage of the battery 140 with the second reference voltage (eg, Figure 8 450V as shown) and a third reference voltage (e.g., Figure 8When the voltage of the battery 140 is greater than or equal to the second reference voltage and less than the third reference voltage (yes in operation 720), operation 725 may include checking the power demand of the DC-DC converter, such as the power demand from the vehicle. Operation 730 may include comparing the power demand with the minimum transition threshold.

[0107] When the power demand is less than the minimum transition threshold (yes in operation 730), operation 735 may include controlling the operation of the bridge driver 210 to transition from the full bridge driver configuration to the half bridge driver configuration. Operation 735 may further include controlling the operation of the bridge driver 210 to operate in the half bridge driver configuration until the power demand from the vehicle is greater than the maximum transition threshold.

[0108] When the power demand is greater than or equal to the minimum transition threshold (No in operation 730), operation 740 may include controlling the operation of the bridge driver 210 to transition from the half-bridge driver configuration to the full-bridge driver configuration. Operation 740 may also include controlling the operation of the bridge driver 210 to operate in the full-bridge driver configuration until the power demand of the vehicle is less than the minimum transition threshold.

[0109] When the voltage of the battery 140 is greater than or equal to the third reference voltage (No in operation 720), operation 750 may include comparing the voltage of the battery 140 with the third reference voltage (e.g., Figure 8 650V as shown) and a fourth reference voltage (e.g., Figure 8 When the voltage of the battery 140 is greater than the third reference voltage and less than the fourth reference voltage (yes in operation 750), operation 755 may include controlling the operation of the bridge driver 210 to operate in a full bridge driver configuration.

[0110] Figure 8 Depicted is an example voltage operated control 800 for a battery charger with a DC-DC converter in accordance with one or more implementations.

[0111] like Figure 8As shown, the battery charger 100 and the DC-DC converter 130 can operate in different configurations based on different battery voltages. For example, when the voltage of the battery 140 is in a first range from 360V to 450V, the DC-DC converter 130 can operate in a half-bridge driver configuration in the low voltage region 810. When the voltage of the battery 140 is in a second range from 450V to 650V, the DC-DC converter 130 can operate in a half-bridge driver configuration or a full-bridge driver configuration in the nominal voltage region 820. When the voltage of the battery 140 is in a third range from 650V to 850V, the DC-DC converter 130 can operate in a full-bridge driver configuration in the full voltage region 830. Here, the first range as the low voltage region 810, the second range as the nominal voltage region 820, and the third range as the full voltage region 830 are provided as non-overlapping ranges increasing from a minimum voltage value to a maximum voltage value. However, these are merely examples, and the present disclosure is not limited to the above configurations or voltage levels. For example, for a 400V system, voltage regions 810, 820, and 830 may be non-overlapping ranges from 170V to 200V, from 200V to 300V, and from 300V to 450V, respectively.

[0112] Fig. 9 A flow chart is depicted of a method of operating a battery charger having a soft-start DC-DC converter in accordance with one or more embodiments.

[0113] Method 900 may control a system including a DC-DC converter 130 and may include various operations of method 900 performed by a controller 300. Operation 901 may include observing one or more of a voltage of a battery 140, an input grid voltage, a DC link voltage, a power requirement, and a state of charge (SOC) of the battery 140. Operation 905 may include comparing the voltage of the battery 140 to a full-bridge voltage threshold. When the voltage of the battery 140 is lower than the full-bridge voltage threshold (no in operation 905), operation 910 may include controlling the operation of the bridge driver 210 to operate in a half-bridge driver configuration and setting a switching frequency and a current reference. Operation 915 may include ramping down a current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate. Operation 920 may include comparing a current reference and a measured current to determine whether an absolute error check is met.

[0114] When the absolute error check is satisfied (yes in operation 920), operation 925 may include comparing the lower limit of the switching frequency ramp to the minimum value. When the lower limit of the switching frequency ramp is equal to the minimum value (yes in operation 925), the soft start method 900 may end at operation 999. When the lower limit of the switching frequency ramp is not equal to the minimum value (no in operation 925), operation 930 may include ensuring that the lower limit of the switching frequency ramp is equal to the minimum value, and ending the soft start method 900 at operation 999.

[0115] When the absolute error check is not satisfied (no in operation 920), operation 970 may include comparing the lower limit of the switching frequency ramp to the minimum value. When the lower limit of the switching frequency ramp is greater than the minimum value (yes in operation 970), method 900 may proceed to operation 915, which may include ramping down the current loop compensator output frequency lower limit from the maximum value to the minimum value at a predetermined soft start rate and continuing as described above.

[0116] When the lower limit of the switching frequency ramp is less than the minimum value (NO in operation 970), operation 975 may include disabling the bridge PWM configuration. Operation 935 may include controlling the operation of the bridge driver 210 to operate in a full bridge driver configuration and setting the switching frequency and current reference.

[0117] When the voltage of the battery 140 is above the full bridge voltage threshold (yes in operation 905), the method 900 may proceed to operation 935. Operation 940 may include ramping down the current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate. Operation 945 may include comparing the current reference and the measured current to determine whether the absolute error check is met.

[0118] When the absolute error check is satisfied ("yes" in operation 945), operation 950 may include comparing the lower limit of the switching frequency ramp to the minimum value. When the lower limit of the switching frequency ramp is equal to the minimum value (yes in operation 950), the soft start method 900 may end at operation 999. When the lower limit of the switching frequency ramp is not equal to the minimum value (no in operation 950), operation 955 may include ensuring that the lower limit of the switching frequency ramp is equal to the minimum value and ending the soft start method 900 at operation 999.

[0119] When the absolute error check is not satisfied (no in operation 945), operation 960 may include comparing the lower limit of the switching frequency ramp to the minimum value. When the lower limit of the switching frequency ramp is greater than the minimum value (yes in operation 960), method 900 may proceed to operation 940 and continue as described above. When the lower limit of the switching frequency ramp is less than the minimum value (no in operation 960), method 900 may generate an error at operation 965.

[0120] Fig.10 A flow chart is depicted of a method of operating a battery charger having a DC-DC converter in accordance with one or more embodiments.

[0121] The method 1000 may control a system including a DC-DC converter 130 and may include performing various operations of the method 1000 by a controller 300. Operation 1010 may include controlling a system including a DC-DC converter 130 including a transformer 240, a bridge driver 210 connected to a primary side of the transformer 240, and a bridge rectifier connected to a secondary side of the transformer 240. Operation 1020 may include controlling one or more switches (211, 212, 213, or 214) in the bridge driver 210 to configure the bridge driver 210 to each of a half-bridge driver configuration and a full-bridge driver configuration, and to transition between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter 130 outputs power.

[0122] Operation 1030 may include receiving a sensed voltage of a battery 140 connected to a DC-DC converter 130, and controlling the operation of one or more switches (211, 212, 213, or 214) to configure the bridge driver 210 as a half-bridge driver configuration when the sensed voltage is in a low voltage region 810, to configure the bridge driver 210 as any one of a half-bridge driver configuration and a full-bridge driver configuration when the sensed voltage is in a nominal voltage region 820, and to configure the bridge driver 210 as a full-bridge driver configuration when the sensed voltage is in a full voltage region 830.

[0123] Operation 1040 may include ramping down the current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate. Operation 1050 may include maintaining a fixed duty cycle of one or more switches (211, 212, 213, or 214) and changing the switching frequency of one or more switches (211, 212, 213, or 214). Operation 1060 may include changing the switching frequency of one or more switches (211, 212, 213, or 214) based on a comparison of the current reference signal and the measured current.

[0124] Several examples of different configurations of the DC-DC converter 130 and the battery charger 100 are provided above. However, the present disclosure is not limited to the examples provided above. Furthermore, any suitable voltage or other signal may be used to control the operation of the switches discussed above.

[0125] The battery charger 100 according to the present disclosure can operate with multiple types of AC input power supplies, including single-phase, split-phase / dual-phase / two-phase and three-phase power supplies. The battery charger 100 is compatible with a wide range of operations. The algorithm can ensure that the DC-DC converter 130 operates under a wide range of input voltage changes to produce a wide range of output voltages. By providing different configurations, the battery charger 100 can reduce the current delivered to the individual devices of the battery charger 100 to reduce the stress on the devices. The battery charger 100 according to the present disclosure can obtain a lower voltage on each switch on the secondary side of the transformer 240, and the performance is enhanced. This lower voltage on each switch can allow the use of lower voltage devices. At least some of the advantages of the disclosed systems and methods are a single resonant topology, which can provide seamless transitions between half-bridge and full-bridge operating modes according to HVDC battery voltage and output power conditions, and vice versa. At least some of the advantages of the disclosed systems and methods are soft start operations, which can be software solutions, ensuring smooth startup of the converter and determining the expected operating mode (half-bridge or full-bridge) without any additional hardware circuits.

[0126] Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. The specification and examples should be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.

Claims

1. A system for a direct current (DC)-DC converter, the system comprising: transformer; a bridge driver connected to the primary side of the transformer; as well as a bridge rectifier connected to the secondary side of the transformer, wherein one or more switches in the bridge driver operatively configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and transition between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power. 2 . The system of claim 1 , further comprising a controller configured to control operation of the one or more switches.

3. The system according to claim 2, wherein: The one or more switches include a first bridge driver switch and a second bridge driver switch on a first branch of the bridge driver, and a third bridge driver switch and a fourth bridge driver switch on a second branch of the bridge driver.

4. The system according to claim 3, wherein: The controller is configured to control operation of the one or more switches to configure the bridge driver into a half-bridge driver configuration by controlling the third bridge driver switch to open and controlling the fourth bridge driver switch to close.

5. The system according to any one of claims 2 to 4, wherein: The controller is also configured to control the operation of the one or more switches to configure the bridge driver as a half-bridge driver configuration when a sensed voltage of a battery connected to the DC-DC converter is in a low voltage region, to configure the bridge driver as a half-bridge driver configuration or a full-bridge driver configuration when the sensed voltage is in a nominal voltage region, and to configure the bridge driver as a full-bridge driver configuration when the sensed voltage is in a full voltage region.

6. The system according to claim 5, wherein: The controller is further configured to, when the sense voltage is in the nominal voltage region, check the power demand of the DC-DC converter, and operating the bridge driver in a half-bridge driver configuration when the power demand is less than a minimum transition threshold, and When the power demand is greater than a minimum transition threshold, the bridge driver is operated in a full bridge driver configuration.

7. The system according to claim 5 or 6, wherein: The controller is also configured to ramp the current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate.

8. The system according to claim 7, wherein: The controller is further configured to maintain a fixed duty cycle of the one or more switches and to vary a switching frequency of the one or more switches.

9. The system according to claim 8, wherein: The controller is further configured to vary the switching frequency based on a comparison of a current reference signal and a measured current.

10. The system according to any one of claims 1 to 9, wherein: The DC-DC converter has a voltage operating range from about 170V to about 850V at a battery interface connected to the bridge rectifier.

11. The system of any one of claims 1 to 10, further comprising an alternating current (AC) to direct current (DC) power factor correction (PFC) converter connected to the bridge driver to provide the system as a battery charger.

12. The system according to claim 11, further comprising: a battery connected to the DC-DC converter of the battery charger, and a motor configured to rotate based on power received from the battery, wherein the system is provided as a vehicle.

13. The system according to claim 12, wherein: The battery charger is configured to: receiving input AC power through the PFC converter, converting the AC power into DC power, and providing the DC power to the battery to charge the battery, and The DC-DC converter receives DC power from the battery, converts the DC power into AC power, and provides the AC power as output AC power through the PFC converter.

14. The system according to any one of claims 1 to 13, wherein: The transformer comprises a high frequency transformer arranged in a resonant circuit.

15. A method of controlling a system including a direct current (DC)-DC converter, the DC-DC converter including a transformer, a bridge driver connected to a primary side of the transformer, and a bridge rectifier connected to a secondary side of the transformer, the method comprising: One or more switches in the bridge driver are controlled to configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and to transition between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

16. The method according to claim 15, wherein: The operations also include receiving a sensed voltage of a battery connected to the DC-DC converter, and Wherein, controlling the switch operation includes controlling the operation of the one or more switches to configure the bridge driver as a half-bridge driver configuration when the sensing voltage is in a low voltage region, to configure the bridge driver as a half-bridge driver configuration or a full-bridge driver configuration when the sensing voltage is in a nominal voltage region, and to configure the bridge driver as a full-bridge driver configuration when the sensing voltage is in a full voltage region.

17. The method according to claim 16, wherein: The operations also include ramping a current loop compensator output frequency lower limit from a maximum value to a minimum value at a predetermined soft start rate.

18. The method according to claim 17, wherein: The operations also include maintaining a fixed duty cycle of the one or more switches and varying a switching frequency of the one or more switches.

19. The method according to claim 18, wherein: Changing the switching frequency of the one or more switches is based on a comparison of the current reference signal and the measured current.

20. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors, perform operations comprising: One or more switches in a bridge driver of a DC-DC converter are controlled to configure the bridge driver into each of a half-bridge driver configuration and a full-bridge driver configuration, and to transition between the half-bridge driver configuration and the full-bridge driver configuration while the DC-DC converter outputs power.

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