Power control circuits, electric vehicles, on-board chargers and their control methods

Abstract

This application provides a power control circuit, an electric vehicle, an on-board charger, and a control method thereof. The control circuit of the on-board charger can control the voltage conversion circuit to operate in different working modes. In addition to enabling the voltage conversion circuit to perform the basic function of energy exchange between the power grid and at least one energy storage device, the voltage conversion circuit can also control the output power of the high-voltage battery when the high-voltage battery in at least one energy storage device supplies power to the first electrical device. This enriches the functions that the on-board charger can achieve, enabling it to be applied in different scenarios and thus meeting the requirements for greater integration and higher power density.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a power control circuit, an electric vehicle, an on-board charger, and a control method thereof. Background Technology

[0002] With the continuous development of electric vehicles, on-board electronic devices are also showing a trend towards miniaturization, integration, and high power density. As the core component for energy conversion in electric vehicles, the on-board charger (OBC) also urgently needs to meet the increasing demands of electric vehicles with a smaller size and higher power density.

[0003] In the existing technology, on-board chargers usually have limited functions, such as converting AC power from the grid into DC power to charge high-voltage or low-voltage batteries, or providing the voltage of high-voltage batteries to external loads of electric vehicles.

[0004] However, the functions provided by existing on-board chargers are relatively limited. Therefore, how to enrich the functions of on-board chargers is a technical problem that needs to be solved in this field. Summary of the Invention

[0005] This application provides a power control circuit, an electric vehicle, an on-board charger, and a control method thereof to overcome the technical problem that the on-board charger has limited functionality in the prior art.

[0006] The first aspect of this application provides an on-board charger, comprising: a PFC circuit connected to a power grid and a voltage conversion circuit; the voltage conversion circuit connected to the PFC circuit, a first electrical device, and at least one energy storage device; and a control circuit for controlling the voltage conversion circuit to operate in an on-board charger mode that converts the voltage between the PFC circuit and the at least one energy storage device, or in a power control mode that controls the power supplied by the at least one energy storage device to the first electrical device.

[0007] A second aspect of this application provides an electric vehicle including an on-board charger as provided in the first aspect of this application.

[0008] A third aspect of this application provides a power control circuit, including a first battery pack, a second battery pack, a third bridge arm, a fourth bridge arm, a capacitor, a third control switch, a fourth control switch, a first inductor, a second inductor, and a third inductor; wherein the load, the capacitor, the third bridge arm, and the fourth bridge arm are connected in parallel in sequence, the midpoint of the third bridge arm is connected between the first battery pack and the second battery pack through the fourth control switch and the second inductor, the midpoint of the fourth bridge arm is connected between the first battery pack and the second battery pack through the third control switch and the first inductor, and the third inductor is disposed between the fourth bridge arm and the positive terminal of the first battery pack.

[0009] A fourth aspect of this application provides a control method for an on-board charger, comprising a first battery pack, a second battery pack, a third bridge arm, a fourth bridge arm, a capacitor, a third control switch, a fourth control switch, a first inductor, a second inductor, and a third inductor; wherein the load, the capacitor, the third bridge arm, and the fourth bridge arm are connected in parallel in sequence, the midpoint of the third bridge arm is connected between the first battery pack and the second battery pack through the fourth control switch and the second inductor, the midpoint of the fourth bridge arm is connected between the first battery pack and the second battery pack through the third control switch and the first inductor, and the third inductor is disposed between the fourth bridge arm and the positive terminal of the first battery pack.

[0010] In summary, the power control circuit, electric vehicle, on-board charger, and control method provided in this application allow the on-board charger's control circuit to operate the voltage conversion circuit in different modes. This enables the voltage conversion circuit to perform the basic function of energy exchange between the power grid and at least one energy storage device. Furthermore, the voltage conversion circuit can control the output power of the high-voltage battery when the high-voltage battery in at least one energy storage device supplies power to the first electrical device. Therefore, the power control circuit, electric vehicle, on-board charger, and control method provided in this application enable the on-board charger to provide different operating modes, enriching the functions it can perform. This allows the on-board charger to be applied in various scenarios, ultimately meeting the requirements for greater integration and higher power density. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1A schematic diagram of the structure of an embodiment of the electric vehicle provided in this application;

[0013] Figure 2 This is a schematic diagram of the structure of an embodiment of the on-board charger provided in this application;

[0014] Figure 3 This is a schematic diagram of the structure of an embodiment of the voltage conversion circuit provided in this application;

[0015] Figure 4 A schematic diagram of the circuit structure of the first voltage conversion module provided in this application;

[0016] Figure 5 A schematic diagram of the circuit structure of the second voltage conversion module provided in this application;

[0017] Figure 6 A schematic diagram of the circuit structure of the third voltage conversion module provided in this application;

[0018] Figure 7 A schematic diagram of the circuit structure of another voltage conversion circuit provided in this application;

[0019] Figure 8 This is a schematic diagram of the circuit structure of a power control circuit provided in this application. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] Figure 1 This is a schematic diagram of the structure of an embodiment of the electric vehicle provided in this application, as shown below. Figure 1As shown, the electric vehicle 1 used in this application includes an on-board charger 10 and at least one energy storage device. The on-board charger 10 (OBC) is the core component in the electric vehicle 1 used for energy conversion. In one embodiment, as... Figure 1 The at least one energy storage device shown includes a high-voltage battery 11 and a low-voltage battery 12, or in another embodiment, at least one energy storage device may include a high-voltage battery 11. In one embodiment, the low-voltage battery 12 may specifically be a load disposed within the electric vehicle 1.

[0023] When the electric vehicle 1 is connected to the external power grid 2, the on-board charger 10 can receive AC power from the external power grid 2, convert the AC power to DC power, and perform voltage conversion and other processing before charging the high-voltage battery 11 or the low-voltage battery 12. Alternatively, when the electric vehicle 1 is connected to a second electrical device 3 outside the electric vehicle 1, the on-board charger 10 can perform voltage conversion and other processing on the DC power provided by the high-voltage voltage 11 before supplying power to the second electrical device 3.

[0024] However, in the existing technology, the on-board charger 10 usually does not have other functions besides the above-mentioned functions, which limits the functions that the on-board charger 10 can achieve. Under the current trend of integration and high power density of on-board equipment for electric vehicles 1, how to enrich the functions of the on-board charger 10, enable the on-board charger 10 to be used in more scenarios, and improve the utilization rate of the on-board charger 10 to meet the needs of integration and high power density of the on-board charger 10 is a technical problem that needs to be solved in this field.

[0025] Based on the technical problems existing in the prior art, this application provides an on-board charger, a battery power control circuit, and an electric vehicle. The technical solution of this application will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0026] Figure 2 This is a schematic diagram of the structure of an embodiment of the on-board charger provided in this application, as shown below. Figure 2 The on-board charger 10 shown can be applied to, for example... Figure 1 In the electric vehicle 1 shown.

[0027] Specifically, such as Figure 2The on-board charger in the electric vehicle 1 shown includes a PFC circuit 101, a voltage conversion circuit 102, and a control circuit 100. The PFC circuit 101 is connected to the power grid 2 and the voltage conversion circuit 102, respectively. The voltage conversion circuit 102 is connected to the PFC circuit 101, the high-voltage battery 11, the low-voltage battery 12, and the first electrical device 14 installed inside the electric vehicle 1.

[0028] The control circuit 100 is connected to the PFC circuit 101 and the voltage conversion circuit 102 respectively. The control circuit 100 can be used to execute the control method of the on-board charger, thereby controlling the PFC circuit 101 and the voltage conversion circuit 102. In this embodiment, when the control circuit 100 executes the control method of the on-board charger, it can be used to control the voltage conversion circuit 102 to operate in different modes.

[0029] PFC circuit 101 can be used to convert between AC power on the grid 2 side and DC power on the voltage conversion circuit 102 side, and improve the power factor.

[0030] The voltage conversion circuit 102 includes two operating modes, denoted as on-board charger mode and power control mode. The control circuit 100 can be used to control the voltage conversion circuit 102 to operate in on-board charger mode or in power control mode. In specific implementations, on-board charger mode may also be referred to as OBC mode, and power control mode may also be referred to as Battery Energy Control (BEC) mode.

[0031] When the voltage conversion circuit 102 operates in on-board charger mode, it can be used to convert the voltage between the PFC circuit and at least one energy storage device; when the voltage conversion circuit 102 operates in power control mode, it can be used to control the power supplied by the high-voltage battery 11 in at least one energy storage device to the first electrical device.

[0032] In one embodiment, when the electric vehicle 1 is in motion, the voltage conversion circuit 102 operates in on-board charger mode; when the electric vehicle 1 is parked, the voltage conversion circuit 102 operates in power control mode. The control circuit 100 can control the voltage conversion circuit 102 according to the state of the electric vehicle, so that the voltage conversion circuit 102 operates in a working state corresponding to the state of the electric vehicle 1.

[0033] Therefore, in the on-board charger 10 provided in this embodiment, the control circuit 100 can control the voltage conversion circuit 102 to operate in different working modes, enabling the voltage conversion circuit 102 to realize the basic function of energy interaction between the power grid 2 and at least one energy storage device. Furthermore, the voltage conversion circuit 102 can also control the output power of the high-voltage battery 12 in at least one energy storage device when it supplies power to the first electrical device 14. Therefore, the on-board charger 10 provided in this embodiment can provide different working modes, enriching the functions that the on-board charger 10 can realize, thus enabling the on-board charger 10 to be applied in different scenarios, and further enabling the on-board charger 10 to meet the requirements for greater integration and higher power density.

[0034] More specifically, in one embodiment of this application, when the voltage conversion circuit 102 operates in on-board charger mode, the control circuit 100 can specifically control the voltage conversion circuit 102 to operate in six different states, each performing a different function. The six operating states that the voltage conversion circuit 102 can achieve are as follows:

[0035] Operating state 1: The power grid 2 charges the high-voltage battery 11 through the PFC circuit 101 and the voltage conversion circuit 102.

[0036] Operating state 2: The power grid 2 charges the low-voltage battery 12 through the PFC circuit 101 and the voltage conversion circuit 102.

[0037] Operating state 3: The high-voltage battery 11 supplies power to the power grid 2 through the voltage conversion circuit 102.

[0038] Operating state 4: The high-voltage battery 11 supplies power to the second electrical device 3 through the voltage conversion circuit 102 and the PFC circuit 101.

[0039] Operating state 5: The high-voltage battery 11 discharges to the low-voltage battery 12 through the voltage conversion circuit 102, thereby charging the low-voltage battery 12.

[0040] Operating state 6: The low-voltage battery 12 discharges to the high-voltage battery 11 through the voltage conversion circuit 102, thereby charging the high-voltage battery 11.

[0041] In one embodiment, the high-voltage battery 11 in at least one energy storage device provided in this application supports multiple different output powers. When the voltage conversion circuit 102 operates in power control mode, the control circuit 100 can specifically control the voltage conversion circuit 102 so that the high-voltage battery 11 supplies power to the first electrical device 14 through the voltage conversion circuit 102 at the target output power among multiple different output powers.

[0042] In one embodiment, such as Figure 2 The high-voltage battery 11 shown specifically includes a first battery pack 111 and a second battery pack 112. The first battery pack 111 can be used to handle the peak output power of the high-voltage battery 11, and it has a higher power density and a higher discharge rate. Therefore, the power density of the first battery pack 111 is greater than that of the second battery pack 112. The second battery pack 112 can be used to handle the main energy storage capacity of the high-voltage battery 11, and it has a higher energy density and can store more energy. Therefore, the energy density of the second battery pack 112 is greater than that of the first battery pack 111.

[0043] When the voltage conversion circuit 102 operates in power control mode, the control circuit 100 can specifically control the voltage conversion circuit 102 according to the power demand of the first electrical device 14 or the charge level of the first battery pack 111, so that the first battery pack 111 and the second battery pack 112 in the high-voltage battery 11 are in different charging and discharging states, supplying power to the first electrical device 14 with different target output power. The voltage conversion circuit 102 can achieve three different operating states, namely:

[0044] Operating state 7: The second battery pack 112 supplies power to the first electrical device 14 through the voltage conversion circuit 102.

[0045] Operating state 8: The first battery pack 111 and the second battery pack 112 together supply power to the first electrical device 14 through the voltage conversion circuit 102.

[0046] Operating state 9: The second battery pack 112 discharges to the first battery pack 111 through the voltage conversion circuit 102, thereby charging the first battery pack 111.

[0047] In one embodiment, when the power demand of the first electrical device 14 is less than or equal to a preset power, it indicates that the power demand of the first electrical device 14 is not high, and the power demand of the second battery pack 112 with a lower power density can be met. Therefore, the control circuit 100 controls the voltage conversion circuit 102 to operate in operating state 7, so that the second battery pack 112 supplies power to the first electrical device 14. When the power of the first electrical device 14 is greater than the preset power, it indicates that the power demand of the first electrical device 14 is high, and the power demand of the first battery pack 111 with a higher power density needs to be met in combination with the second battery pack 112. Therefore, the control circuit 100 controls the voltage conversion circuit 102 to operate in operating state 8, so that the first battery pack 111 and the second battery pack 112 jointly supply power to the first electrical device 14.

[0048] In one embodiment, when the power of the first battery pack 111 is less than the preset power, it indicates that the first battery pack 111 needs to be charged. Then, the control circuit 100 controls the voltage conversion circuit 102 to work in working state 8, so that the second battery pack 112 charges the first battery pack 111.

[0049] In summary, the on-board charger 10 provided in this embodiment can achieve a total of 9 different working states based on two working modes, thereby realizing more working states on the basis of different working modes, further enriching and refining the functions that the on-board charger 10 can achieve, and further improving the integration and intelligence of the on-board charger 10.

[0050] Meanwhile, the high-voltage battery 11 provided in this embodiment supports multiple different output powers through the configuration of the first battery pack 111 and the second battery pack 112, so that the high-voltage battery 11 as a whole has a higher power density. Combined with the control circuit 100's control of the voltage conversion circuit 102, the high-voltage battery 11 can not only meet the energy density requirements, but also ensure power and increase battery life to a certain extent.

[0051] The on-board charger 10 provided in this embodiment can connect to different battery packs, thus enabling the sharing of batteries with different lifespan systems and different chemical systems. This allows the high-voltage battery 11 to be electrically connected without being constrained by the cell energy density and power density, through a relatively simple circuit topology. In this way, the potential of the entire high-voltage battery 11 can be fully utilized through the joint control of multiple battery packs.

[0052] Figure 3 This is a schematic diagram of the structure of an embodiment of the voltage conversion circuit provided in this application, as shown below. Figure 3 The voltage conversion circuit 102 shown can be applied to, for example... Figure 2 The on-board charger 10 shown.

[0053] Specifically, such as Figure 3 The voltage conversion circuit 102 shown includes: a first voltage conversion module 1021, a transformer 1020, a second voltage conversion module 1022, and a third voltage conversion module 1023. The transformer 1020 includes a primary winding, a first secondary winding, and a second secondary winding. The first voltage conversion module 1021 is connected to the PFC circuit 101 and the primary winding, respectively. The second voltage conversion module 1022 is connected to the first secondary winding, the first battery pack 111 and the second battery pack of the high-voltage battery 11, and the internal load 14, respectively. The third DC / DC module 1023 is connected to the second secondary winding and the low-voltage battery 12, respectively.

[0054] Furthermore, the voltage conversion circuit 102 provided in this application can realize an on-board charger mode for converting the voltage between the PFC circuit 101 and at least one energy storage device, and a power control mode for controlling the power supplied by at least one energy storage device to the first electrical device 14. Specifically, Figure 3 In the voltage conversion circuit 102 shown, the second voltage conversion module 1022 includes two functional units: a voltage conversion unit and a power supply unit. Components can be reused between the two functional units. For example, the voltage conversion unit and the power supply unit can reuse at least two bridge arms.

[0055] Specifically, when the voltage conversion circuit 102 is in the on-board charger mode, the voltage conversion unit of the second voltage conversion module 1022 can be used to convert the AC power of the first secondary winding and the DC power between the high-voltage battery 11 to each other, and the power supply unit is in a non-working state at this time; when the voltage conversion circuit 102 is in the power control mode, the power supply unit of the second voltage conversion module 1022 can be used to control the power supplied by the high-voltage battery 11 to the first electrical device 14, and the voltage conversion unit is in a non-notifying state at this time.

[0056] Therefore, the voltage conversion circuit 102 provided in this embodiment combines the on-board charger mode and power control mode supported by the voltage conversion circuit 102 with the reuse of the second voltage conversion module 1022, and implements them in the same conversion module. This effectively improves the integration of the on-board charger and enriches its functions without significantly increasing the design complexity and cost of the circuit.

[0057] Figure 4 A schematic diagram of the circuit structure of the first voltage conversion module provided in this application is shown below. Figure 4 It shows Figure 3 This diagram illustrates a specific implementation of the first voltage conversion module 1021 in the voltage conversion circuit 102 shown. Specifically, the first voltage conversion module 1021 includes: a first switch K4, a first resonant capacitor Cr1, a first resonant inductor Lr1, a first bridge arm, and a second bridge arm. The first bridge arm includes an upper bridge arm Q5 and a lower bridge arm Q7, and the second bridge arm includes an upper bridge arm Q6 and a lower bridge arm Q8. The first bridge arm, the first switch K4, the primary winding 1220a, the first resonant capacitor Cr1, and the second bridge arm are connected sequentially.

[0058] In one embodiment, such as Figure 4 The PFC circuit shown includes: capacitor L1, inductor C1, inductor C2, fourth switch K1, fifth switch K2, sixth switch K3, seventh bridge arm, and eighth bridge arm. The seventh bridge arm includes upper bridge arm Q1 and lower bridge arm Q3, and the eighth bridge arm includes upper bridge arm Q2 and lower bridge arm Q4. The fourth switch K1 is used to connect to power grid 2. Power grid 2 is... Figure 4The equivalent voltage source Vin, the fifth switch K2 is used to connect the external second electrical device 3, the second electrical device 3 in Figure 4 The equivalent is resistor R1. The sixth switch K3 is used to connect capacitor C1. After the voltage source Vin, resistor R1 and capacitor C1 are connected in parallel, they are connected in sequence to capacitor L1, the seventh bridge arm, inductor C2 and the eighth bridge arm.

[0059] Figure 5 The circuit structure diagram of the second voltage conversion module provided in this application is as follows: Figure 5 It shows Figure 3 This diagram illustrates a specific implementation of the second voltage conversion module 1022 in the voltage conversion circuit 102 shown. Specifically, the second voltage conversion module 1022 includes: a second switch K5, a second resonant capacitor Cr2, a second resonant inductor Lr2, a first control switch K10, a second control switch K9, a third control switch K7, a fourth control switch K8, a capacitor C3, a first inductor Boost1, a second inductor Boost2, a third inductor Boost3, a third bridge arm, and a fourth bridge arm. The third bridge arm includes an upper bridge arm Q9 and a lower bridge arm Q11, and the fourth bridge arm includes an upper bridge arm Q10 and a lower bridge arm Q12.

[0060] The components are connected in sequence: the second switch K5, the second resonant inductor Lr2, the midpoint of the third bridge arm, the junction points at both ends of the third bridge arm, the first control switch K10, the first battery pack 111 and the second battery pack 112 of the high-voltage battery 11, the junction points at both ends of the fourth bridge arm, the second resonant capacitor Cr2, and the second secondary winding 1220b. Simultaneously, the first electrical device 14, capacitor C3, the third bridge arm, and the fourth bridge arm are connected in parallel. The second control switch K9 is positioned between capacitor C3 and the third bridge arm. The midpoint of the third bridge arm is connected between the first battery pack 111 and the second battery pack 112 of the high-voltage battery 11 via the fourth control switch K8 and the second inductor Boost2. The midpoint of the fourth bridge arm is connected between the first battery pack 111 and the second battery pack 112 of the high-voltage battery 11 via the third control switch K7 and the first inductor Boost1. The third inductor Boost3 and the first control switch K10 are connected in parallel and positioned between the fourth bridge arm and the positive terminal of the first battery pack 111.

[0061] When the voltage conversion circuit 102 is in on-board charger mode, the second switch K5, the second resonant capacitor Cr2, the second resonant inductor Lr2, the first control switch K10, the third bridge arm, and the fourth bridge arm in the second voltage conversion module 1022 form a voltage conversion unit. When the voltage conversion circuit 102 is in power control mode, the third bridge arm, the fourth bridge arm, the capacitor C3, the second control switch K9, the third control switch K7, the fourth control switch K8, the first inductor Boost1, the second inductor Boost2, and the third inductor Boost3 in the second voltage conversion module 1022 form a power supply unit.

[0062] Figure 6 A schematic diagram of the circuit structure of the third voltage conversion module provided in this application is shown below. Figure 6 It shows Figure 3 This diagram illustrates a specific implementation of the third voltage conversion module 1023 in the voltage conversion circuit 102 shown. Specifically, the third voltage conversion module 1023 includes: a third switch K6, a fourth resonant capacitor Cr3, a third resonant inductor Lr3, a fifth bridge arm, and a sixth bridge arm. The fifth bridge arm includes an upper bridge arm Q13 and a lower bridge arm Q15, and the sixth bridge arm includes an upper bridge arm Q14 and a lower bridge arm Q16. The third switch K5, the third resonant inductor Lr3, the fifth bridge arm, the low-voltage battery 12, the sixth bridge arm, the third resonant capacitor Cr3, and the second secondary winding 1220c are connected sequentially.

[0063] Combination Figure 4 , Figure 5 and Figure 6 The complete circuit structure of the voltage conversion circuit 102 shown can be controlled by the control circuit 100 to control the voltage conversion circuit 102 to work in different modes and to be in different working states in different modes by controlling different bridge arms in the voltage conversion circuit 102.

[0064] In one embodiment, the control circuit 100 specifically controls the second switch K5 and the first control switch K10 to be turned on, and controls the second control switch K7, the third control switch K8 and the fourth control switch K9 to be turned off, so that the voltage conversion circuit 102 operates in the on-board charger mode.

[0065] In one embodiment, the control circuit 100 specifically controls the second switch K5 and the first control switch K10 to be disconnected, and controls the second control switch K7, the third control switch K8 and the fourth control switch K9 to be turned on, so that the voltage conversion circuit 102 operates in power control mode.

[0066] More specifically, when the voltage conversion circuit 102 operates in on-board charger mode:

[0067] The control circuit 100 specifically controls the third switch K6 to be open, controls the first switch K4 and the third switch K5 to be open, and controls the fourth switch K1 in the PFC circuit 101 to be open, and controls the fifth switch K2 and the sixth switch K3 to be open, thereby controlling the first bridge arm, the second bridge arm, the seventh bridge arm and the eighth bridge arm to make the voltage conversion circuit 102 work in working state 1.

[0068] The control circuit 100 specifically controls the second switch K5 to be open, controls the first switch K4 and the third switch K5 to be open, and controls the fourth switch K1 in the PFC circuit 101 to be open, and controls the fifth switch K2 and the sixth switch K3 to be open, thereby controlling the first bridge arm, the second bridge arm, the seventh bridge arm and the eighth bridge arm to make the voltage conversion circuit 102 work in working state 2.

[0069] The control circuit 100 specifically controls the third switch K6 to be open, controls the first switch K4 and the second switch K5 to be open, and controls the fourth switch K1 in the PFC circuit 101 to be open, and controls the fifth switch K2 and the sixth switch K3 to be open, thereby controlling the upper arm of the third bridge arm and the upper arm of the fourth bridge arm to make the voltage conversion circuit 102 work in working state 3.

[0070] The control circuit 100 specifically controls the first switch K4 to be open, controls the second switch K5 and the third switch K6 to be open, and controls the fourth switch K1 in the PFC circuit 101 to be open, and controls the fifth switch K2 and the sixth switch K3 to be open, thereby controlling the upper arm of the third bridge arm and the upper arm of the fourth bridge arm to make the voltage conversion circuit 102 work in working state 4.

[0071] The control circuit 100 specifically controls the first switch K4 to open and the second switch K5 and the third switch K6 to open, thereby controlling the third bridge arm and the fourth bridge arm to make the voltage conversion circuit 102 work in working state 5.

[0072] Specifically, the control circuit 100 controls the first switch K4 to open and the second switch K5 and the third switch K6 to open, thereby controlling the fifth bridge arm and the sixth bridge arm to make the voltage conversion circuit 102 work in working state 6.

[0073] More specifically, when the voltage conversion circuit 102 operates in power control mode:

[0074] Specifically, the control circuit 100 controls the third and fourth bridge arms to alternately turn on and off according to the first switching frequency, so that the second battery pack 112 supplies power to the first electrical device 14 through the third and fourth bridge arms, and the voltage conversion circuit 102 operates in working state 7.

[0075] Specifically, the control circuit 100 controls the upper bridge arm Q9 of the third bridge arm and the lower bridge arm Q12 of the fourth bridge arm to conduct, so that the first battery pack 111 and the second battery pack 112 are connected in series and together supply power to the first electrical device 14 through the third bridge arm and the fourth bridge arm, so that the voltage conversion circuit 102 works in working state 8.

[0076] Specifically, the control circuit 100 controls the third and fourth bridge arms to alternately turn on and off according to the second switching frequency, so that the second battery pack 112 charges the first battery pack 111 through the third and fourth bridge arms, and the voltage conversion circuit 102 operates in working state 9.

[0077] In summary, by controlling the switches and bridge arms in the voltage conversion circuit 102, the control circuit 100 enables the voltage conversion circuit 102 to operate in at least nine different working states, greatly enriching the functions of the voltage conversion circuit 102 and the on-board charger 10 in which it is located. Furthermore, the control logic of the control circuit 100 is relatively simple and efficient, which can reduce the time and computing power costs required by the control circuit 100. This is beneficial for the application and promotion of the on-board charger 10 and the control method executed by the control circuit 100 provided in this application.

[0078] In a specific implementation, the control circuit 100 can control the voltage conversion circuit 102 to operate in different working modes according to the instructions of other devices or electric vehicle users. Alternatively, the control circuit 100 can also control the voltage conversion circuit 102 to operate in different working modes according to the pre-configured conditions, thereby improving the automation and intelligence of the control method.

[0079] Furthermore, this application also provides another implementation of the voltage conversion circuit 102, wherein the structure of the other voltage conversion circuit 102 is similar to... Figure 3 The same as shown, and the first voltage conversion module 1021, the transformer and the third voltage conversion module 1023 are all the same, the only difference is the second voltage conversion module 1022.

[0080] Specifically, Figure 7 A schematic diagram of the circuit structure of another voltage conversion circuit provided in this application is shown below. Figure 7 The second voltage conversion module 1022 shown includes: a second switch K5, a second resonant capacitor Cr2, a second resonant inductor Lr2, a capacitor C3, a third bridge arm, and a fourth bridge arm. The third bridge arm includes an upper bridge arm Q9 and a lower bridge arm Q11, and the fourth bridge arm includes an upper bridge arm Q10 and a lower bridge arm Q12. The second switch K5, the second resonant inductor Lr2, the midpoint of the third bridge arm, the junction points at both ends of the third bridge arm, the high-voltage battery 11, the junction points at both ends of the fourth bridge arm, the second resonant capacitor Cr2, and the second secondary winding 1220b are connected sequentially.

[0081] Then by Figure 4 , Figure 6 and Figure 7 The voltage conversion circuit 102 formed can also be controlled by the control circuit 100 to operate in any one of the following states: working state 1, working state 2, working state 3, working state 4, working state 5, or working state 6.

[0082] Based on the foregoing of this application Figure 5 The second voltage conversion module 1022 provided in the illustrated embodiment integrates a voltage conversion unit and a power supply unit to achieve different operating modes. The power supply unit, used for power control in power control mode, can also exist as a separate circuit.

[0083] For example, Figure 8 A schematic diagram of the circuit structure of a power control circuit provided in this application is shown below. Figure 8 The power control circuit shown includes: a first battery pack 111, a second battery pack 112, a capacitor C3, a third control switch K7, a fourth control switch K8, a first inductor Boost1, a second inductor Boost2, a third inductor Boost3, a third bridge arm, and a fourth bridge arm. The third bridge arm includes an upper bridge arm Q9 and a lower bridge arm Q11, and the fourth bridge arm includes an upper bridge arm Q10 and a lower bridge arm Q12. R is the equivalent load of the battery.

[0084] The battery load, capacitor C3, third bridge arm, and fourth bridge arm are connected in parallel in sequence. The midpoint of the third bridge arm is connected between the first battery pack 111 and the second battery pack 112 through the fourth control switch K8 and the second inductor Boost2. The midpoint of the fourth bridge arm is connected between the first battery pack 111 and the second battery pack 112 through the third control switch K7 and the first inductor Boost1. The third inductor Boost3 is located between the fourth bridge arm and the positive terminal of the first battery pack 111.

[0085] like Figure 8The power control circuit shown can achieve different operating states by controlling the states of the third control switch K7, the fourth control switch K8, the third bridge arm, and the fourth bridge arm. For example, the control circuit specifically controls the third and fourth bridge arms to alternately turn on and off according to a first switching frequency, allowing the third and fourth bridge arms of the second battery pack 112 to supply power to the first electrical device 14. Specifically, the control circuit 100 controls the upper bridge arm Q9 of the third bridge arm and the lower bridge arm Q12 of the fourth bridge arm to turn on, so that the first battery pack 111 and the second battery pack 112 are connected in series and jointly supply power to the first electrical device 14 through the third and fourth bridge arms. Specifically, the control circuit 100 controls the third and fourth bridge arms to alternately turn on and off according to a second switching frequency, allowing the second battery pack 112 to charge the first battery pack 111 through the third and fourth bridge arms.

[0086] Finally, it should be noted that in the foregoing embodiments of this application, the structure and different working modes and states of the on-board charger 10 provided in this application have been described. To achieve the control of each working mode and state of the on-board charger 10 provided in the embodiments of this application, the control circuit 100, as the execution entity, can be implemented through hardware structures and / or software modules. For example, it can be implemented using hardware structures, software modules, or a combination of hardware structures and software modules. Whether a particular function is executed using hardware structures, software modules, or a combination of hardware structures and software modules depends on the specific application and design constraints of the technical solution.

[0087] In the above embodiments, the control executed by the control circuit 100 can be implemented wholly or partially through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented wholly or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks (SSDs)).

[0088] For example, this application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed, can be used to implement a control method or step performed by any of the control circuits 100 in the foregoing embodiments of this application.

[0089] This application also provides a chip for executing instructions, the chip being used to execute control methods or steps as performed by any of the control circuits 100 described above.

[0090] This application also provides a computer program product, including a computer program that, when executed, implements a control method or steps as performed by any of the control circuits 100 described above.

[0091] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An on-board charger, characterized in that, include: The PFC circuit is connected to the mains and the voltage conversion circuit respectively; The voltage conversion circuit is connected to the PFC circuit, the first electrical device, and at least one energy storage device, respectively. A control circuit is used to control the voltage conversion circuit to operate in an on-board charger mode that converts the voltage between the PFC circuit and the at least one energy storage device, or in a power control mode that controls the power supplied by the at least one energy storage device to the first electrical device. The voltage conversion circuit includes: A transformer includes a primary winding, a first secondary winding, and a second secondary winding; The first voltage conversion module is connected to the PFC circuit and the primary winding, respectively; The second voltage conversion module is connected to the first secondary winding, the high-voltage battery, and the internal load, respectively. The third voltage conversion module is connected to the second secondary winding and the low-voltage battery, respectively. The second voltage conversion module includes: a power supply unit, used to control the power supplied by the high-voltage battery to the first electrical device; The power supply unit includes: a third bridge arm, a fourth bridge arm, a capacitor, a second control switch, a third control switch, a fourth control switch, a first inductor, a second inductor, and a third inductor; wherein, the first electrical device, the capacitor, the third bridge arm, and the fourth bridge arm are connected in parallel in sequence, the second control switch is disposed between the capacitor and the third bridge arm, the midpoint of the third bridge arm is connected between the first battery pack and the second battery pack through the fourth control switch and the second inductor, the midpoint of the fourth bridge arm is connected between the first battery pack and the second battery pack through the third control switch and the first inductor, and the third inductor and the first control switch are connected in parallel and disposed between the fourth bridge arm and the positive terminal of the first battery pack.

2. The on-board charger according to claim 1, characterized in that, The at least one energy storage device includes a high-voltage battery; when the voltage conversion circuit operates in the power control mode, the control circuit is specifically used for: By controlling the voltage conversion circuit, the high-voltage battery supplies power to the first electrical device at a target output power among the multiple output powers supported by the high-voltage battery.

3. The on-board charger according to claim 2, characterized in that, The control circuit is specifically used for: Based on the power requirements of the first electrical device, the voltage conversion circuit is controlled to enable the high-voltage battery to supply power to the first electrical device at the target output power.

4. The on-board charger according to claim 3, characterized in that, The high-voltage battery includes a first battery pack and a second battery pack; wherein the power density of the first battery pack is greater than the power density of the second battery pack, and the energy density of the second battery pack is greater than the energy density of the first battery pack.

5. The on-board charger according to claim 4, characterized in that, The control circuit is specifically used for: When the power demand of the first electrical device is less than or equal to the preset power, the voltage conversion circuit is controlled to supply power to the first electrical device from the second battery pack. When the power demand of the first electrical device exceeds the preset power, the voltage conversion circuit is controlled so that the first battery pack and the second battery pack jointly supply power to the first electrical device.

6. The on-board charger according to claim 4 or 5, characterized in that, The control circuit is also used for: When the power of the first battery pack is less than the preset power, the voltage conversion circuit is controlled to enable the second battery pack to charge the first battery pack.

7. The on-board charger according to any one of claims 2-5, characterized in that, The at least one energy storage device further includes a low-voltage battery. When the voltage conversion circuit operates in the on-board charger mode, the control circuit is specifically used for: The voltage conversion circuit is controlled to charge the high-voltage battery from the power grid, or to charge the low-voltage battery from the power grid, or to supply power from the high-voltage battery to the power grid, or to supply power from the high-voltage battery to a second electrical device, or to charge the low-voltage battery from the high-voltage battery, or to charge the high-voltage battery from the low-voltage battery.

8. The on-board charger according to claim 1, characterized in that, The second voltage conversion module includes: A voltage conversion unit is used to convert between the AC power of the first secondary winding and the DC power of the high-voltage battery.

9. The on-board charger according to claim 8, characterized in that, The voltage conversion unit includes: The second switch, the second resonant capacitor, the second resonant inductor, the first control switch, the third bridge arm, and the fourth bridge arm; The second switch, the second resonant inductor, the midpoint of the third bridge arm, the junction points at both ends of the third bridge arm, the first control switch, the high-voltage battery, the junction points at both ends of the fourth bridge arm, the second resonant capacitor, and the second secondary winding are connected in sequence.

10. The on-board charger according to claim 1, characterized in that, The control circuit is specifically used for: The third and fourth bridge arms are controlled according to the first switching frequency, so that the second battery pack supplies power to the first electrical device through the third and fourth bridge arms.

11. The on-board charger according to claim 1, characterized in that, The control circuit is specifically used for: The upper arm of the third bridge arm and the lower arm of the fourth bridge arm are connected to the circuit, so that the first battery pack and the second battery pack are connected in series and jointly supply power to the first electrical device through the third bridge arm and the fourth bridge arm.

12. The on-board charger according to claim 1, characterized in that, The control circuit is specifically used for: The third and fourth bridge arms are controlled according to the second switching frequency, so that the second battery pack charges the first battery pack through the third and fourth bridge arms.

13. The on-board charger according to any one of claims 9-12, characterized in that, The first voltage conversion module includes: First switch, first resonant capacitor, first resonant inductor, first bridge arm and second bridge arm; The first bridge arm, the first resonant inductor, the first switch, the primary winding, the first resonant capacitor, and the second bridge arm are connected in sequence.

14. The on-board charger according to claim 13, characterized in that, The third voltage conversion module includes: The third switch, the third resonant capacitor, the third resonant inductor, the fifth bridge arm, and the sixth bridge arm; The third switch, the third resonant inductor, the fifth bridge arm, the low-voltage battery, the sixth bridge arm, the third resonant capacitor, and the second secondary winding are connected in sequence.

15. The on-board charger according to claim 14, characterized in that, The control circuit is specifically used for: The second and first control switches are turned on, and the second, third, and fourth control switches are turned off, so that the voltage conversion circuit operates in on-board charger mode.

16. The on-board charger according to claim 14, characterized in that, The control circuit is specifically used for: The second and first control switches are disconnected, and the second, third, and fourth control switches are turned on, so that the voltage conversion circuit operates in power control mode.

17. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: The third switch is controlled to open, and the first and third switches are controlled to open, as well as the first and second bridge arms are controlled, so that the power grid charges the high-voltage battery.

18. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: The second switch is controlled to open, and the first and second switches are controlled to open, as well as the first and second bridge arms are controlled, so that the power grid charges the low-voltage battery.

19. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: The third switch is controlled to open, and the first and second switches are controlled to open, as well as the upper arms of the third and fourth bridge arms are controlled, so that the high-voltage battery supplies power to the power grid.

20. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: Controlling the first switch and the second switch to turn on, and controlling the upper arm of the third bridge arm and the upper arm of the fourth bridge arm, enables the high-voltage battery to supply power to the second electrical device.

21. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: The first switch is controlled to open, and the second and third switches are controlled to open, as well as the third and fourth bridge arms are controlled, so that the high-voltage battery charges the low-voltage battery.

22. The on-board charger according to claim 15 or 16, characterized in that, The control circuit is specifically used for: The first switch is controlled to open, and the second and third switches are controlled to open, as well as the fifth and sixth bridge arms are controlled, so that the low-voltage battery charges the high-voltage battery.

23. An electric vehicle, characterized in that, Includes the on-board charger as described in any one of claims 1-22.

24. A power control circuit, characterized in that, include: First battery pack, second battery pack, third bridge arm, fourth bridge arm, capacitor, third control switch, fourth control switch, first inductor, second inductor and third inductor; The load, the capacitor, the third bridge arm, and the fourth bridge arm are connected in parallel in sequence. The midpoint of the third bridge arm is connected between the first battery pack and the second battery pack through the fourth control switch and the second inductor. The midpoint of the fourth bridge arm is connected between the first battery pack and the second battery pack through the third control switch and the first inductor. The third inductor is disposed between the fourth bridge arm and the positive terminal of the first battery pack.

25. A control method for an on-board charger, characterized in that, The on-board charger includes a PFC circuit and a voltage conversion circuit. The PFC circuit is connected to the power grid and the voltage conversion circuit, respectively. The voltage conversion circuit is connected to the PFC circuit, a first electrical device, and at least one energy storage device, respectively. The control method includes: The voltage conversion circuit is controlled to operate in either an on-board charger mode that converts the voltage between the PFC circuit and the at least one energy storage device, or a power control mode that controls the power supplied by the at least one energy storage device to the first electrical device. The voltage conversion circuit includes: A transformer includes a primary winding, a first secondary winding, and a second secondary winding; The first voltage conversion module is connected to the PFC circuit and the primary winding, respectively; The second voltage conversion module is connected to the first secondary winding, the high-voltage battery, and the internal load, respectively. The third voltage conversion module is connected to the second secondary winding and the low-voltage battery, respectively. The second voltage conversion module includes: a power supply unit, used to control the power supplied by the high-voltage battery to the first electrical device; The power supply unit includes: a third bridge arm, a fourth bridge arm, a capacitor, a second control switch, a third control switch, a fourth control switch, a first inductor, a second inductor, and a third inductor; In this configuration, the first electrical device, the capacitor, the third bridge arm, and the fourth bridge arm are connected in parallel in sequence. The second control switch is disposed between the capacitor and the third bridge arm. The midpoint of the third bridge arm is connected between the first battery pack and the second battery pack through the fourth control switch and the second inductor. The midpoint of the fourth bridge arm is connected between the first battery pack and the second battery pack through the third control switch and the first inductor. The third inductor and the first control switch are connected in parallel and disposed between the fourth bridge arm and the positive terminal of the first battery pack.

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