Charging system and electric vehicle

Abstract

The present application provides a charging system and an electric vehicle, the charging system comprising a motor controller MCU and a first inductor, the first bridge arm and the first inductor in the MCU forming a voltage conversion circuit, the MCU can step up the power supply voltage through the voltage conversion circuit when the power supply voltage is less than the minimum charging voltage of the power battery, and output the stepped-up power supply voltage as a first output voltage to the power battery, the first output voltage being not less than the minimum charging voltage. The present application can reduce the space and cost occupied by the charging system while using the charging system to step down the power supply voltage.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a charging system and an electric vehicle. Background Art

[0002] With the development of new energy technology, electric vehicles have received increasing attention. Electric vehicles are equipped with power batteries, which can receive and store the power provided by the charging pile, and release the stored power during the driving of the electric vehicle to drive the electric vehicle.

[0003] In order to increase the charging speed of electric vehicles, more and more electric vehicles use 800V high-voltage power batteries. The maximum battery voltage of the power battery is 800V, and the required charging voltage may exceed 800V. However, the output voltage of most DC fast charging piles on the market is 500V. These charging piles cannot directly charge 800V high-voltage power batteries, causing electric vehicles equipped with high-voltage power batteries to face charging difficulties, which is not conducive to improving user experience.

[0004] Therefore, the charging scheme for electric vehicles still needs further research. Summary of the invention

[0005] In view of this, the present application provides a charging system and an electric vehicle, which are beneficial for the electric vehicle to still support the power supply voltage to charge the power battery when the power supply voltage is lower than the minimum charging voltage of the power battery.

[0006] In the first aspect, the present application provides a charging system, including a motor controller MCU and a first inductor, the MCU including N bridge arms, N being an integer greater than or equal to 1. The high potential ends of the N bridge arms are connected to the first power supply end and the first battery end of the charging system, the first power supply end can be connected to the positive pole of the DC power supply, the first battery end can be connected to the positive pole of the power battery, the DC power supply can output the power supply voltage, and the power battery can receive the first output voltage of the charging system. The low potential ends of the N bridge arms are connected to the second battery end of the charging system, and the second battery end can be connected to the negative pole of the power battery. One end of the first inductor is connected to the second power supply end, the other end of the first inductor is connected to the middle point of the first bridge arm, the second power supply end can be connected to the negative pole of the DC power supply, and the first bridge arm is any one of the N bridge arms. The N bridge arms of the MCU and the first inductor constitute a voltage conversion circuit, and the MCU can perform a voltage conversion on the power supply voltage through the voltage conversion circuit when the power supply voltage is less than the minimum charging voltage of the power battery, and output the power supply voltage after the voltage conversion as the first output voltage to the power battery, and the first output voltage is not less than the minimum charging voltage.

[0007] In summary, the present application realizes a charging system by reusing the MCU. When the power supply voltage is less than the minimum charging voltage of the power battery, the charging system can perform a step-up conversion on the power supply voltage to obtain a first output voltage that is not less than the above-mentioned minimum charging voltage, and the first output voltage can be adapted to the power battery, so as to charge the power battery. At the same time, the present application reuses the MCU commonly used in electric vehicles, which is also conducive to reducing the space and cost occupied by the charging system.

[0008] Exemplarily, the first aspect of the present application provides the following examples for illustration:

[0009] Example 1

[0010] The first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point of the first bridge arm is located between the first switch tube and the second switch tube. When the power supply voltage is less than the minimum charging voltage, the MCU can turn on the first switch tube to charge the first inductor. The MCU turns off the first switch tube to discharge the first inductor.

[0011] Specifically, when the MCU turns on the first switch tube, the current is output from the positive electrode of the DC power supply, reaches the first inductor after passing through the first switch tube, and charges the first inductor. When the MCU turns off the first switch tube, the first inductor begins to discharge. The current is output from one end of the first inductor close to the second power supply end, and after being transmitted through the DC power supply, the power battery, and the diode in the second switch tube, it flows back to the end of the first inductor close to the second switch tube. In this process, the DC power supply and the first inductor are discharged in series, and the first output voltage is the sum of the power supply voltage and the voltage of the first inductor. Obviously, the first output voltage is greater than the power supply voltage, so boost conversion can be achieved.

[0012] It can be understood that the power supply voltage provided by the DC power supply may also be within the charging voltage range of the power battery, that is, the power supply voltage is adapted to the power battery. In order to be compatible with this scenario, the charging system in the present application may also include a first switch, the first end of the first switch is connected to the second battery end, and the second end of the first switch is connected to the second power supply end. The MCU can also turn on the first switch when the power supply voltage is within the charging voltage range of the power battery; and turn off the first switch when the power supply voltage is outside the charging voltage range of the power battery.

[0013] Specifically, when the first switch is turned on, the power battery can be directly connected to the DC power supply, so the power battery can directly receive the power supply voltage provided by the DC power supply to complete charging. Therefore, when the power supply voltage is within the charging voltage range of the power battery, the first switch can be turned on. When the first switch is turned off, the MCU can convert the power supply voltage and provide the converted power supply voltage as the first output voltage to the power battery. Therefore, when the power supply voltage is outside the charging voltage range of the power battery, the first switch can be turned off.

[0014] In order to adapt to high-power scenarios, the charging system may include N first inductors and N third switches, wherein one end of the N third switches is connected to the second power supply end, the other end of the N third switches is connected to one end of the N first inductors in a one-to-one correspondence, and the other end of the N first inductors is connected to the N bridge arms in a one-to-one correspondence. The N third switches can be turned on when receiving the power supply voltage and turned off when stopping receiving the power supply voltage.

[0015] Specifically, when the N third switches are turned on, the charging and discharging of the N first inductors can be controlled respectively through the N bridge arms. In other words, the N first inductors can transmit power in parallel, so they can adapt to high-power scenarios. When the power supply voltage is stopped, the N third switches are turned off, so that the N first inductors are disconnected from each other, which is conducive to reducing the impact of the N first inductors on the inverter function of the MCU.

[0016] Example 2

[0017] It can be foreseen that in some scenarios, the power supply voltage may also be greater than the maximum charging voltage of the power battery. In view of this, in this application, the MCU can also step down the power supply voltage through the voltage conversion circuit when the power supply voltage is greater than the maximum charging voltage of the power battery, and output the power supply voltage after the step-down conversion as the first output voltage to the power battery, and the first output voltage is not greater than the maximum charging voltage. In this case, the electric vehicle can receive a larger power supply voltage, and after converting the power supply voltage, the power battery is charged, which is conducive to improving the convenience of charging.

[0018] Exemplarily, the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point of the first bridge arm is located between the first switch tube and the second switch tube. The charging system may also include a first switch and a second switch, wherein the first end of the first switch is connected to the second battery terminal, the second end of the first switch is connected to the second power supply terminal, the first end of the second switch is connected to the first battery terminal, the second end of the second switch is connected to one end of the first inductor, and the third end of the second switch is connected to the first power supply terminal.

[0019] Based on the charging system, when the power supply voltage is greater than the maximum charging voltage, the MCU can turn on the first switch and turn on the first end and the second end of the second switch. The MCU turns on the first switch tube to charge the first inductor. The MCU turns off the first switch tube to discharge the first inductor.

[0020] Specifically, after the MCU turns on the first switch tube, the first inductor can be charged, and the first output voltage is the voltage difference between the power supply voltage and the voltage of the first inductor. After the MCU turns off the first switch tube, the first inductor can be discharged, and the first output voltage is the voltage of the first inductor. It can be seen that the first output voltage is always less than the power supply voltage, so the charging system can step down the power supply voltage.

[0021] It should be noted that the charging system provided in this example 2 can also perform a step-up conversion on the power supply voltage. Exemplarily, the charging system may also include a third switch, a first end of the third switch is connected to one end of the first inductor, and a second end of the third switch is connected to the second power supply end. When the power supply voltage is less than the minimum charging voltage, the MCU can turn on the first end and the third end of the second switch, turn on the third switch, and turn off the first switch. The MCU turns on the first switch tube to charge the first inductor. The MCU turns off the first switch tube to discharge the first inductor.

[0022] Specifically, after the MCU turns on the first switch tube, the first inductor can be charged. After the MCU turns off the first switch tube, the first inductor can be discharged. At this time, the first output voltage is the sum of the voltage of the first inductor and the power supply voltage. It can be seen that the first output voltage is greater than the power supply voltage, so the charging system can perform a boost conversion on the power supply voltage.

[0023] In addition, the charging system provided in this example 2 can also perform buck-boost conversion on the power supply voltage. Exemplarily, the charging system may also include a third switch, a first end of the third switch is connected to one end of the first inductor, and a second end of the third switch is connected to the second power supply end. The MCU may turn on the first end and the second end of the second switch, and turn on the third switch. The MCU turns on the first switch tube to charge the first inductor. Turn off the first switch tube to discharge the first inductor.

[0024] Specifically, the MCU can charge the first inductor after turning on the first switch tube. The MCU can discharge the first inductor after turning off the first switch tube, and the first output voltage is the voltage of the first inductor. The voltage of the first inductor depends on the charging time of the first inductor. Therefore, the first output voltage can be adjusted by adjusting the charging time of the first inductor. The first output voltage may be greater than the power supply voltage (boost conversion) or less than the power supply voltage (buck conversion).

[0025] It can be understood that the charging system provided in Example 2 of the present application is also compatible with the scenario where the power supply voltage matches the power battery. Exemplarily, the MCU can also turn on the first and third ends of the second switch and the first switch when the power supply voltage is within the charging voltage range of the power battery. In this case, the power battery is directly connected to the DC power supply and can directly receive the power supply voltage to complete charging.

[0026] In the second aspect, the present application also provides a charging system, mainly including a motor controller MCU and a first inductor. Among them, the MCU includes N bridge arms, and N is an integer greater than or equal to 1. The high potential ends of the N bridge arms of the MCU are connected to the first power supply end and the first battery end of the charging system, the first power supply end can be connected to the positive pole of the DC load, the first battery end can be connected to the positive pole of the power battery, the DC load can receive the second output voltage of the charging system, and the power battery can output the battery voltage to the charging system. The low potential ends of the N bridge arms in the MCU are connected to the second battery end of the charging system, and the second battery end can be connected to the negative pole of the power battery. One end of the above-mentioned first inductor is connected to the second power supply end, and the other end of the first inductor is connected to the first bridge arm, the second power supply end can be connected to the negative pole of the DC load, and the first bridge arm is any bridge arm among the N bridge arms. The first bridge arm and the first inductor constitute a voltage conversion circuit. When the battery voltage is greater than the maximum operating voltage of the DC load, the MCU can step down the battery voltage through the voltage conversion circuit and output the stepped-down battery voltage as a second output voltage to the DC load. The second output voltage is not greater than the maximum operating voltage.

[0027] In summary, the present application realizes a charging system by reusing the MCU. When the battery voltage is greater than the maximum operating voltage of the DC load, the charging system can step down the battery voltage to obtain a second output voltage not greater than the above maximum operating voltage, and the second output voltage can be adapted to the DC load, thereby supplying power to the DC load. At the same time, the present application reuses the MCU commonly used in electric vehicles, which is also conducive to reducing the space and cost occupied by the charging system.

[0028] Exemplarily, the second aspect of the present application provides the following examples for illustration:

[0029] Example 1

[0030] Exemplarily, the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point of the first bridge arm is located between the first switch tube and the second switch tube. When the battery voltage is greater than the maximum operating voltage, the MCU can turn on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0031] Specifically, after the MCU turns on the second switch tube, the first inductor can be charged. At this time, the first output voltage is the voltage difference between the power supply voltage and the voltage of the first inductor. After the MCU turns off the second switch tube, the first inductor can be discharged, and at this time, the first output voltage is the voltage of the first inductor. It can be seen that the first output voltage is always less than the battery voltage. Therefore, the charging system provided in Example 1 of the present application can realize the step-down conversion of the battery voltage.

[0032] It is understandable that the battery voltage of the power battery may also be adapted to the DC load. In order to be compatible with this scenario, the charging system may further include a first switch, the first end of the first switch is connected to the second battery end, and the second end of the first switch is connected to the second power supply end. The MCU may also turn on the first switch when the battery voltage is within the operating voltage range of the DC load; and turn off the first switch when the battery voltage is outside the operating voltage range of the DC load.

[0033] When the first switch is turned on, the power battery can be directly connected to the DC load to directly supply power to the DC load. When the first switch is turned off, the MCU can convert the battery voltage and provide the converted battery voltage to the DC load as the second output voltage.

[0034] In order to adapt to high-power scenarios, the charging system may include N first inductors and N third switches, one end of the N third switches is connected to the second power supply end, the other end of the N third switches is connected to one end of the N first inductors in a one-to-one correspondence, and the other end of the N first inductors is connected to the N bridge arms in a one-to-one correspondence. The N third switches can be turned on when the second output voltage is output, and turned off when the second output voltage stops being output.

[0035] Specifically, when the N third switches are turned on, the charging and discharging of the N first inductors can be controlled respectively through the N bridge arms. In other words, the N first inductors can transmit power in parallel, so they can adapt to high-power scenarios. When the power supply voltage is stopped, the N third switches are turned off, so that the N first inductors are disconnected from each other, which is conducive to reducing the impact of the N first inductors on the inverter function of the MCU.

[0036] Example 2

[0037] It is foreseeable that in some scenarios, the battery voltage may be lower than the minimum operating voltage of the DC load. In view of this, the MCU in this application can also step up the battery voltage through the voltage conversion circuit when the battery voltage is lower than the minimum operating voltage of the DC load, and output the stepped-up battery voltage as the second output voltage to the DC load, and the second output voltage is not lower than the minimum operating voltage.

[0038] Exemplarily, the first bridge arm in the MCU includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point of the first bridge arm is located between the first switch tube and the second switch tube. The charging system may also include a first switch and a second switch, wherein the first end of the first switch is connected to the second battery terminal, the second end of the first switch is connected to the second power supply terminal, the first end of the second switch is connected to the first battery terminal, the second end of the second switch is connected to one end of the first inductor, and the third end of the second switch is connected to the first power supply terminal.

[0039] Based on the charging system, when the battery voltage is less than the minimum operating voltage, the MCU can turn on the first switch and turn on the first end and the second end of the second switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0040] Specifically, the MCU can charge the first inductor after turning on the second switch tube. The MCU can discharge the first inductor after turning off the second switch tube. At this time, the second output voltage is the sum of the battery voltage and the voltage of the first inductor. It can be seen that the second output voltage is greater than the battery voltage, so the charging system can perform a step-up conversion on the battery voltage.

[0041] It should be noted that the charging system provided in this example 2 can also perform a step-down conversion on the battery voltage. Exemplarily, the charging system may further include a third switch, a first end of the third switch being connected to one end of the first inductor, and a second end of the third switch being connected to the second power supply end. When the battery voltage is greater than the maximum operating voltage, the MCU may turn on the first end and the third end of the second switch, turn on the third switch, and turn off the first switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0042] Specifically, after the MCU turns on the second switch tube, the first inductor can be charged, and the second output voltage is the voltage difference between the battery voltage and the voltage of the first inductor. After the MCU turns off the second switch tube, the first inductor can be discharged, and the second output voltage is the voltage of the first inductor. It can be seen that the second output voltage is always less than the battery voltage, so the charging system can perform a step-down conversion on the battery voltage.

[0043] In addition, the charging system provided in this example 2 can also perform buck-boost conversion on the battery voltage. Exemplarily, the charging system may also include a third switch, a first end of the third switch is connected to one end of the first inductor, and a second end of the third switch is connected to the second power supply end. The MCU may turn on the first end and the second end of the second switch, and turn on the third switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0044] Specifically, the MCU can charge the first inductor after turning on the second switch tube. The MCU can discharge the first inductor after turning off the second switch tube. At this time, the second output voltage is the voltage of the first inductor. The voltage of the first inductor depends on the charging time of the first inductor. Therefore, by adjusting the charging time of the first inductor, the size of the second output voltage can be adjusted. The second output voltage may be greater than the battery voltage (boost conversion) or less than the battery voltage (buck conversion).

[0045] It can be understood that the charging system provided in Example 2 of the present application is also compatible with the scenario where the battery voltage matches the DC load. Exemplarily, the MCU can also turn on the first and third ends of the second switch and the first switch when the battery voltage is within the operating voltage range of the power battery. In this case, the power battery is directly connected to the DC load and can directly power the DC load.

[0046] In the third aspect, the present application provides a charging system, which mainly includes a motor controller MCU and a first inductor. The MCU includes N bridge arms, where N is an integer greater than or equal to 1. Among them, the high potential ends of the N bridge arms are connected to the first battery end of the charging system, the first battery end can be connected to the positive electrode of the power battery, and the power battery can receive the first output voltage of the charging system. The low potential ends of the N bridge arms are connected to the second battery end and the second power supply end of the charging system, the second battery end can be connected to the negative electrode of the power battery, the second power supply end can be connected to the negative electrode of the DC power supply, and the DC power supply can output the power supply voltage. One end of the first inductor is connected to the first power supply end, and the other end of the first inductor is connected to the middle point of the first bridge arm. The first power supply end can be connected to the positive electrode of the DC power supply, and the first bridge arm is any one of the N bridge arms. The first bridge arm and the first inductor constitute a voltage conversion circuit. When the power supply voltage is less than the minimum charging voltage of the power battery, the MCU can perform a voltage conversion on the power supply voltage through the voltage conversion circuit, and output the power supply voltage after the voltage conversion as a first output voltage to the power battery, and the first output voltage is not less than the minimum charging voltage; when the power supply voltage is greater than the maximum charging voltage of the power battery, the power supply voltage is stepped down through the voltage conversion circuit, and the power supply voltage after the voltage conversion is output to the power battery as a first output voltage, and the first output voltage is not greater than the minimum charging voltage.

[0047] Exemplarily, the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point of the first bridge arm is located between the first switch tube and the second switch tube. The charging system also includes a sixth switch and a fifth switch, wherein the first end of the fifth switch is connected to the second battery terminal, the second end of the fifth switch is connected to the low potential end of the N bridge arms, the third end of the fifth switch is connected to one end of the first inductor, the first end of the sixth switch is connected to the first battery terminal, and the second end of the sixth switch is connected to the first power supply terminal.

[0048] When the power supply voltage is greater than the maximum charging voltage, the MCU can turn on the sixth switch, turn on the first end and the third end of the fifth switch, turn on the second switch tube to charge the first inductor, and turn off the second switch tube to discharge the first inductor.

[0049] Specifically, after the MCU turns on the second switch tube, the first inductor can be charged, and the first output voltage is the voltage difference between the power supply voltage and the voltage of the first inductor. After the MCU turns off the second switch tube, the first inductor can be discharged, and the first output voltage is the voltage of the first inductor. It can be seen that the first output voltage is always less than the power supply voltage, so the charging system can perform a step-down conversion on the power supply voltage.

[0050] It should be noted that the charging system provided in the third aspect of the present application can also perform a step-up conversion on the power supply voltage. Exemplarily, the charging system may further include a fourth switch, a first end of the fourth switch being connected to one end of the first inductor, and a second end of the fourth switch being connected to the first power supply end. When the power supply voltage is less than the minimum charging voltage, the MCU may turn on the first and second ends of the fifth switch, turn on the fourth switch, and turn off the sixth switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0051] Specifically, the MCU can charge the first inductor after turning on the second switch tube. The MCU can discharge the first inductor after turning off the second switch tube. At this time, the first output voltage is the sum of the voltage of the first inductor and the power supply voltage. It can be seen that the first output voltage is greater than the power supply voltage, so the charging system can perform a step-up conversion on the power supply voltage.

[0052] In addition, the charging system provided in the third aspect of the present application can also perform buck-boost conversion on the power supply voltage. Exemplarily, the charging system may further include a fourth switch, a first end of the fourth switch being connected to one end of the first inductor, and a second end of the fourth switch being connected to the first power supply end. The MCU may turn on the first end and the third end of the fifth switch, and turn on the fourth switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0053] Specifically, the MCU can charge the first inductor after turning on the second switch tube. The MCU can discharge the first inductor after turning off the second switch tube, and the first output voltage is the voltage of the first inductor. The voltage of the first inductor depends on the charging time of the first inductor. Therefore, by adjusting the charging time of the first inductor, the magnitude of the first output voltage can be adjusted. The first output voltage may be greater than the power supply voltage (boost conversion) or less than the power supply voltage (buck conversion).

[0054] It can be understood that the charging system provided in the third aspect of the present application can also be compatible with the scenario where the power supply voltage matches the power battery. Exemplarily, the MCU can also turn on the first and second ends of the fifth switch and the sixth switch when the power supply voltage is within the charging voltage range of the power battery. In this case, the power battery is directly connected to the DC power supply and can directly receive the power supply voltage to complete charging.

[0055] In a fourth aspect, the present application provides a charging system, which mainly includes a motor controller MCU and a first inductor. The MCU includes N bridge arms, where N is an integer greater than or equal to 1. Among them, the high potential ends of the N bridge arms are connected to the first battery terminal of the charging system, the first battery terminal can be connected to the positive electrode of the power battery, and the power battery can output the battery voltage to the charging system. The low potential ends of the N bridge arms are connected to the second battery terminal and the second power supply terminal of the charging system, the second battery terminal can be connected to the negative electrode of the power battery, the second power supply terminal can be connected to the negative electrode of the DC load, and the DC load can receive the second output voltage of the charging system. One end of the first inductor is connected to the first power supply terminal, and the other end of the first inductor is connected to the middle point of the first bridge arm, the first power supply terminal can be connected to the positive electrode of the DC load, and the first bridge arm is any one of the N bridge arms. The first bridge arm and the first inductor can constitute a voltage conversion circuit. When the battery voltage is greater than the maximum operating voltage of the DC load, the MCU can step down the battery voltage through the voltage conversion circuit, and output the battery voltage after the step-down conversion as the second output voltage to the DC load, and the second output voltage is not greater than the maximum operating voltage; when the battery voltage is less than the minimum operating voltage of the DC load, the battery voltage is stepped up through the voltage conversion circuit, and the battery voltage after the step-up conversion is output to the DC load as the second output voltage, and the second output voltage is not less than the minimum operating voltage.

[0056] Exemplarily, the first bridge arm of the MCU includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is connected to the first battery terminal and the first power supply terminal respectively, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point is located between the first switch tube and the second switch tube. The charging system also includes a sixth switch and a fifth switch, the first end of the fifth switch is connected to the second battery terminal, the second end of the fifth switch is connected to the low potential end of the N bridge arms, the third end of the fifth switch is connected to one end of the first inductor, the first end of the sixth switch is connected to the first battery terminal, and the second end of the sixth switch is connected to the first power supply terminal.

[0057] Based on the charging system, when the battery voltage is less than the minimum operating voltage, the MCU can turn on the sixth switch, turn on the first end and the third end of the fifth switch, turn on the first switch tube to charge the first inductor, and turn off the first switch tube to discharge the first inductor.

[0058] Specifically, the MCU can charge the first inductor after turning on the first switch tube. The MCU can discharge the first inductor after turning off the first switch tube. At this time, the second output voltage is the sum of the battery voltage and the voltage of the first inductor. It can be seen that the second output voltage is greater than the battery voltage, so the charging system can perform a boost conversion on the battery voltage.

[0059] It should be noted that the charging system provided in the fourth aspect of the present application can also perform a step-down conversion on the battery voltage. Exemplarily, the charging system may further include a fourth switch, a first end of the fourth switch being connected to one end of the first inductor, and a second end of the fourth switch being connected to the first power supply end. When the battery voltage is greater than the maximum operating voltage, the MCU may turn on the first end and the second end of the fifth switch, turn on the fourth switch, and turn off the sixth switch. The MCU turns on the second switch tube to charge the first inductor. The MCU turns off the second switch tube to discharge the first inductor.

[0060] Specifically, after the MCU turns on the first switch tube, the first inductor can be charged, and the second output voltage is the voltage difference between the battery voltage and the voltage of the first inductor. After the MCU turns off the first switch tube, the first inductor can be discharged, and the second output voltage is the voltage of the first inductor. It can be seen that the second output voltage is always less than the battery voltage, so the charging system can perform a step-down conversion on the battery voltage.

[0061] In addition, the charging system provided in the fourth aspect of the present application can also perform buck-boost conversion on the battery voltage. Exemplarily, the charging system may also include a fourth switch, a first end of the fourth switch is connected to one end of the first inductor, and a second end of the fourth switch is connected to the first power supply end. The MCU can turn on the first end and the third end of the fifth switch, and turn on the fourth switch. The MCU turns on the first switch tube to charge the first inductor. The MCU turns off the first switch tube to discharge the first inductor.

[0062] Specifically, the MCU can charge the first inductor after turning on the first switch tube. The MCU can discharge the first inductor after turning off the first switch tube, and the second output voltage is the voltage of the first inductor. The voltage of the first inductor depends on the charging time of the first inductor. Therefore, by adjusting the charging time of the first inductor, the size of the second output voltage can be adjusted. The second output voltage may be greater than the battery voltage (boost conversion) or less than the battery voltage (buck conversion).

[0063] It can be understood that the charging system provided in the fourth aspect of the present application is also compatible with the scenario where the battery voltage matches the DC load. Exemplarily, the MCU can also turn on the first and second ends of the fifth switch and the sixth switch when the battery voltage is within the operating voltage range of the DC load. In this case, the power battery is directly connected to the DC load and can directly power the DC load.

[0064] In a fifth aspect, the present application provides an electric vehicle, which mainly includes a power battery and a charging system as provided in any one of the first to fourth aspects above, and the charging system can charge the power battery.

[0065] These and other aspects of the present application will become more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 A schematic diagram of an electric vehicle charging scenario;

[0067] Figure 2 is a schematic diagram of an electric drive system;

[0068] Figure 3 A schematic diagram of a charging system provided in an embodiment of the present application;

[0069] Figure 4 It is one of the boost conversion states of the charging system provided in the embodiment of the present application;

[0070] Figure 5 This is the second boost conversion state of the charging system provided in the embodiment of the present application;

[0071] Figure 6 A schematic diagram of a specific charging system provided in an embodiment of the present application;

[0072] Figure 7 A schematic diagram of a specific charging system provided in an embodiment of the present application;

[0073] Figure 8 It is one of the step-down conversion states of the charging system provided in the embodiment of the present application;

[0074] Fig. 9 This is the second step-down conversion state of the charging system provided in the embodiment of the present application;

[0075] Fig.10 A schematic diagram of a specific charging system provided in an embodiment of the present application;

[0076] Fig.11 One of the switch states of the charging system provided in the embodiment of the present application;

[0077] Fig.12 The third step-down conversion state of the charging system provided in the embodiment of the present application;

[0078] Fig.13 This is the fourth step-down conversion state of the charging system provided in the embodiment of the present application;

[0079] Fig.14 This is a second switch state of the charging system provided in the embodiment of the present application;

[0080] Fig.15 This is a third switch state of the charging system provided in the embodiment of the present application;

[0081] Fig.16 One of the buck-boost conversion states of the charging system provided in the embodiment of the present application;

[0082] Fig.17 The second buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0083] Fig.18 The third boost conversion state of the charging system provided in the embodiment of the present application;

[0084] Fig.19 This is the fourth boost conversion state of the charging system provided in the embodiment of the present application;

[0085] Fig. 20 The third buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0086] Fig.21 The fourth buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0087] Fig. 22 A schematic diagram of another charging system provided in an embodiment of the present application;

[0088] Fig.23 This is a fourth switching state of the charging system provided in the embodiment of the present application;

[0089] Fig.24 The fifth step-down conversion state of the charging system provided in the embodiment of the present application;

[0090] Fig.25 The sixth step-down conversion state of the charging system provided in the embodiment of the present application;

[0091] Fig.26 A fifth switching state of the charging system provided in the embodiment of the present application;

[0092] Fig. 27 This is a sixth switch state of the charging system provided in the embodiment of the present application;

[0093] Fig.28 The fifth buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0094] Fig.29 The sixth buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0095] Fig.30 The fifth boost conversion state of the charging system provided in the embodiment of the present application;

[0096] Fig.31 The sixth boost conversion state of the charging system provided in the embodiment of the present application;

[0097] Fig.32 The seventh buck-boost conversion state of the charging system provided in the embodiment of the present application;

[0098] Fig.33 This is the eighth buck-boost conversion state of the charging system provided in the embodiment of the present application. DETAILED DESCRIPTION

[0099] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The specific operating method in the method embodiment can also be applied to the device embodiment or the system embodiment. It should be noted that in the description of the present application, "at least one" refers to one or more, wherein multiple refers to two or more. In view of this, "multiple" can also be understood as "at least two" in the embodiment of the present invention. "And / or" describes the association relationship of the associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / ", unless otherwise specified, generally indicates that the related objects before and after are in an "or" relationship. In addition, it should be understood that in the description of the present application, words such as "first" and "second" are only used to distinguish the purpose of description, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying order.

[0100] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0101] Electric vehicles, also known as new energy vehicles, are vehicles powered by electricity. Figure 1 As shown, the electric vehicle 10 mainly includes a power battery 12, a motor 13 and wheels 14. The power battery 12 is a large-capacity, high-power storage battery. When the electric vehicle 10 is running, the power battery 12 can supply power to the motor 13 through a motor control unit (MCU) 111, and the motor 13 converts the electrical energy provided by the power battery 12 into mechanical energy, thereby driving the wheels 14 to rotate and realize the vehicle running.

[0102] When the electric vehicle 10 is charged, the electric vehicle 10 can generally be charged through the charging pile 20. Figure 1As shown, the charging pile 20 mainly includes a power circuit 21 and a charging gun 22. One end of the power circuit 21 is connected to the power frequency power grid 30, and the other end is connected to the charging gun 22 through a cable. At present, most charging piles 20 are DC charging piles, and the power circuit 21 can convert the AC power provided by the power frequency power grid 30 into DC power. The operator can insert the charging gun 22 into the charging socket of the electric vehicle 10 to connect the charging gun 22 to the power battery 12 in the electric vehicle 10, and the power circuit 21 of the charging pile 20 can then charge the power battery 12 through the charging gun 22.

[0103] The output voltage of the charging pile 20 can be understood as the power supply voltage received by the electric vehicle 10. In the DC fast charging scenario, the power supply voltage received by the electric vehicle 10 is within the charging voltage range of the power battery 12, and the power battery 12 can be directly charged using the output voltage of the charging pile 20.

[0104] The lower limit of the charging voltage range of the power battery 12 is the minimum charging voltage, which can be understood as the minimum value of the charging voltage that the power battery 12 can adapt. The upper limit of the charging voltage range of the power battery 12 is the maximum charging voltage, which can be understood as the maximum value of the charging voltage that the power battery 12 can adapt.

[0105] At present, in order to improve the charging speed of the electric vehicle 10, the voltage level of the power battery 12 will gradually increase from the current 500V to 800V. Taking the power battery 12 with a voltage level of 800V as an example, the battery voltage of the power battery 12 can reach 800V, and the required charging voltage is often not less than 800V. However, for the charging piles 20 that support DC fast charging on the market, their voltage level is generally 500V, that is, the maximum output voltage of most charging piles 20 that support DC fast charging is 500V. This makes many electric vehicles 10 equipped with high-voltage power batteries face the problem of difficulty in charging.

[0106] In view of this, an embodiment of the present application provides a charging system 11, which is connected to a power battery 12. When charging the electric vehicle 10, the charging system 11 can receive a power supply voltage. When the power supply voltage is less than the minimum charging voltage of the power battery 12, the charging system 11 can boost the power supply voltage and provide the boosted power supply voltage to the power battery 12 as a first output voltage.

[0107] As in the above example, the output voltage of the charging pile 20 is 500 V, that is, the power supply voltage received by the charging system 11 is 500 V. Assuming that the charging voltage that the power battery 12 can adapt to is 960 V, the charging system 11 can step up the power supply voltage to 960 V, thereby providing the power battery 12 with a first output voltage of 960 V, so that the power battery 12 can complete charging using the first output voltage.

[0108] It should be noted that, in order to save the space occupied by the charging system 11 in the electric vehicle 10 and control the cost of the charging system 11, the charging system 11 in the embodiment of the present application can be implemented on the basis of the MCU 111 in the electric vehicle 10. Among them, the MCU 111 and the motor 13 are generally integrated into the electric drive system. In other words, the charging system 11 in the embodiment of the present application can be implemented by improving the conventional electric drive system.

[0109] Specifically, the motor 13 relies on the electromagnetic induction effect to realize the conversion of electrical energy into mechanical energy, so a motor winding is provided in the motor 13. At present, the number of motor windings in the motor 13 is mostly 3 or 6. Taking a three-phase motor as an example, Figure 2 As shown, the MCU 111 includes three bridge arms, the motor 13 includes three motor windings (N1 to N3), and the three bridge arms in the MCU 111 are connected to the three motor windings in the motor 13 in a one-to-one correspondence.

[0110] The first bridge arm includes a switch tube T1 and a switch tube T2, the first electrode of the switch tube T1 is used to connect to the positive electrode of the power battery 12, the second electrode of the switch tube T1 is connected to the first electrode of the switch tube T2, and the second electrode of the switch tube T2 is used to connect to the negative electrode of the power battery 12. The middle point of the first bridge arm, that is, the connection point between the switch tube T1 and the switch tube T2, is connected to one end of the motor winding N1.

[0111] The second bridge arm includes a switch tube T3 and a switch tube T4, the first electrode of the switch tube T3 is used to connect to the positive electrode of the power battery 12, the second electrode of the switch tube T3 is connected to the first electrode of the switch tube T4, and the second electrode of the switch tube T4 is used to connect to the negative electrode of the power battery 12. The middle point of the second bridge arm, that is, the connection point between the switch tube T3 and the switch tube T4, is connected to one end of the motor winding N2.

[0112] The third bridge arm includes a switch tube T5 and a switch tube T6, the first electrode of the switch tube T6 is used to connect the positive electrode of the power battery 12, the second electrode of the switch tube T3 is connected to the first electrode of the switch tube T4, and the second electrode of the switch tube T4 is used to connect the negative electrode of the power battery 12. The middle point of the third bridge arm is the connection point between the switch tube T5 and the switch tube T6. The middle point of the third bridge arm is connected to one end of the motor winding N3, and the other ends of the three motor windings are connected.

[0113] The MCU111 also includes a control board (not shown in the figure). The control board is connected to the control electrodes of the switch tubes T1 to T6, respectively, and controls the conduction and shutdown of the switch tubes T1 to T6, respectively, so that the three bridge arms can convert the battery voltage output by the power battery 12 into three-phase alternating current, and each bridge arm corresponds to one phase of the three-phase alternating current. The MCU111 outputs the three-phase alternating current to the motor 13, so that the motor windings N1 to N3 generate a spatial rotating magnetic field, thereby driving the motor rotor to rotate, and then converting electrical energy into mechanical energy.

[0114] It should be pointed out that the switch tube in the embodiment of the present application can be one or more of various types of switch tubes such as relays, metal oxide semiconductor field effect transistors (metal oxide semiconductor field effect transistors, MOSFET), bipolar junction transistors (bipolar junction transistors, BJT), insulated gate bipolar transistors (insulated gate bipolar transistors, IGBT), etc. The embodiment of the present application will not list them one by one. Each switch tube can include a first electrode, a second electrode and a control electrode, wherein the control electrode is used to control the on or off of the switch tube. When the switch tube is turned on, current can be transmitted between the first electrode and the second electrode of the switch tube, and when the switch tube is turned off, current cannot be transmitted between the first electrode and the second electrode of the switch tube. Taking IGBT as an example, in the embodiment of the present application, the first electrode of the switch tube can be a collector, the second electrode can be an emitter, and the control electrode can be a gate electrode.

[0115] Generally speaking, if Figure 2 As shown, a switch K2 and a switch K5 may be provided between the power battery 12 and the MCU 111. For example, the switch K2 and the switch K5 may be relays. The switch tube K2 and the switch tube K5 may be integrated with the power battery 12 in the battery pack, or may be provided independently, and the embodiment of the present application does not impose any restrictions on this.

[0116] One end of the switch K2 is connected to the anode of the power battery 12, and the other end of the switch K2 is connected to the high potential ends of the three bridge arms. One end of the switch K5 is connected to the cathode of the power battery 12, and the other end of the switch K5 is connected to the low potential ends of the three bridge arms. When the switch K2 and the switch K5 are turned on, the power battery 12 can supply power to the MCU 111. When the switch K2 and the switch K5 are turned off, the power battery 12 stops supplying power to the MCU 111.

[0117] From the above introduction to the MCU 111 and the motor 13, it can be seen that the MCU 111 includes N bridge arms, where N is an integer greater than or equal to 1. It can be understood that when the electric vehicle 10 is charged, the electric vehicle 10 often does not need to move, that is, at this time, the MCU 111 does not need to provide three-phase electricity for the motor 13. Therefore, the embodiment of the present application can realize charging of the power battery 12 based on the N bridge arms in the MCU without affecting the driving function of the electric vehicle 10.

[0118] Next, the charging system 11 provided in the embodiment of the present application is further illustrated by the following examples.

[0119] Embodiment 1

[0120] Exemplarily, the charging system 11 provided in the embodiment of the present application includes an MCU 111 and a motor 13. The MCU 111 includes N bridge arms, and the motor 13 includes N motor windings, the N bridge arms and the N motor windings are respectively connected one-to-one, and N is an integer greater than or equal to 1.

[0121] Take N=3 as an example, Figure 3 As shown, the charging system 11 includes an MCU 111 and a motor 13. The first battery terminal of the charging system 11 is connected to the positive electrode of the power battery 12, the second battery terminal is connected to the negative electrode of the power battery 12, the first power terminal of the charging system 11 is connected to the positive electrode of the DC power supply, and the second power terminal of the charging system is connected to the negative electrode of the DC power supply.

[0122] Among them, the DC power supply can be a charging pile, another electric car, etc., and the embodiments of the present application do not impose many restrictions on this. The DC power supply can output a power supply voltage. The charging system 11 receives the power supply voltage through the first power supply terminal and the second power supply terminal, converts the power supply voltage into a first output voltage adapted to the power battery 12, and outputs it to the power battery 12 through the first battery terminal and the second battery terminal. The power battery 12 can receive the first output voltage provided by the charging system 11, thereby completing the charging.

[0123] Specifically, if Figure 3As shown, MCU111 includes three bridge arms. In the embodiment of the present application, the high potential ends of the three bridge arms in MCU111 are connected to the first power supply terminal, and the low potential ends of the three bridge arms are connected to the second battery terminal of the charging system 11. The charging system 11 also includes an inductor L1, one end of the inductor L1 is connected to the second power supply terminal, and the other end of the inductor L2 is connected to the middle point of any bridge arm in MCU11. Figure 3 In the specific example shown, the other end of the inductor L2 is connected to the middle point of the bridge arm 2 where the switch tube T3 and the switch tube T4 are located.

[0124] In this case, the three bridge arms in MCU111 and the inductor L1 can form a voltage conversion circuit, so that MCU111 can control the on and off of each switch tube among the switch tubes T1 to T6 to enable the above voltage conversion circuit to convert the power supply voltage.

[0125] Therefore, when the power supply voltage is lower than the minimum charging voltage of the power battery 12 , the MCU 111 can boost the power supply voltage through the voltage conversion circuit, and output the boosted power supply voltage as a first output voltage to the power battery, and the first output voltage is not lower than the minimum charging voltage of the power battery 12 .

[0126] For example, the power supply voltage is 500 V, and the minimum charging voltage of the power battery 12 is 960 V. The MCU 111 can boost the power supply voltage to 960 V or above, thereby providing an adaptive first output voltage for the power battery 12 so that the power battery 12 can be charged.

[0127] Generally speaking, if Figure 3 As shown, the charging system 11 also includes a switch K3 and a switch K4. The switch K3 and the switch K4 can also be called a fast contactor. Among them, one end of the switch K3 is connected to the connection point of the motor windings N1 to N3, and the other end of the switch K3 is connected to the second power supply terminal. One end of the switch K4 is connected to the high potential end of the three bridge arms, and the other end of the switch K4 is connected to the first power supply terminal. When the switch K3 and the switch K4 are turned on, the DC power supply can supply power to the charging system 11. When the switch K3 and the switch K4 are turned off, the DC power supply can stop supplying power to the charging system 11.

[0128] Next, taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the process of the boost conversion is further illustrated. Among them, the middle point of the bridge arm 2 is also the connection point of the switch tube T3 and the switch tube T4. One end of the inductor L1 is connected to the second power supply terminal, and the other end of the inductor L1 is connected to the middle point of the bridge arm 2. When the power supply voltage is boosted, it mainly includes the following two stages:

[0129] Phase 1: Charging of inductor L1

[0130] MCU111 can turn on the switch tube T3 to charge the inductor L1. It can be understood that the switch tube T4 is turned off at this time. Figure 4 As shown, the current is output from the positive electrode of the DC power supply, transmitted through the switch tube T3 and the inductor L1, and then flows back to the negative electrode of the DC power supply, thereby forming a charging loop to charge the inductor L1.

[0131] Phase 2: Inductor L1 discharges

[0132] MCU111 can turn off the switch tube T3, and the inductor L1 can no longer receive current through the switch tube T3. Due to the freewheeling characteristic of the inductor, the inductor L1 begins to discharge. Figure 5 As shown, the current is output from the end of the inductor L1 close to the second power supply end, and after being transmitted through the DC power supply, the power battery 12 and the diode in the switch tube T4, it flows back to the end of the inductor L1 close to the switch tube T4. In this process, the first output voltage of the charging system 11 is the sum of the power supply voltage of the DC power supply and the voltage of the inductor L1. Obviously, the first output voltage is greater than the power supply voltage of the DC power supply, thereby realizing the boost conversion.

[0133] It can be understood that when the power of the DC power supply is relatively large, the MCU 111 can also synchronously control multiple bridge arms to perform boost conversion. Figure 6 As shown, MCU111 includes three inductors (inductors L1-1 to L1-3) and three switches K3 (switch K3-1 to switch K3-3), one end of switches K3-1 to K3-3 are all connected to the second power supply end, and the other ends of switches K3-1 to K3-3 are connected to one end of the three inductors (inductors L1-1 to L1-3) in a one-to-one correspondence. Specifically, switch K3-1 is connected to one end of inductor L1-1, switch K3-2 is connected to one end of inductor L1-2, and switch K3-3 is connected to one end of inductor L1-3.

[0134] The three inductors are connected to the middle points of the three bridge arms in MCU111 in a one-to-one correspondence. Among them, one end of the inductor L1-1 is connected to the second power supply terminal of the charging system 11, and the other end of the inductor L1-1 is connected to the middle point between the switch tube T1 and the switch tube T2. One end of the inductor L1-2 is connected to the second power supply terminal of the charging system 11, and the other end of the inductor L1-2 is connected to the middle point between the switch tube T3 and the switch tube T4. One end of the inductor L1-3 is connected to the second power supply terminal of the charging system 11, and the other end of the inductor L1-3 is connected to the middle point between the switch tube T5 and the switch tube T6.

[0135] When charging the power battery 12, the MCU111 can turn on the switches K3-1 to K3-3. The MCU111 can synchronously control the on and off of the switch tubes T1, T3, and T5, so that the inductors L1-1 to L1-3 are synchronously charged and discharged. In this case, it is equivalent to three inductors working in parallel, so as to support voltage conversion in high-power scenarios. After stopping charging the power battery 12, the MCU111 can turn off the switches K3-1 to K3-3. In this case, the inductors L1-1 to L1-3 are open circuited, which can reduce the influence of the inductors L1-1 to L1-3 on the inverter process of the MCU111.

[0136] In summary, the charging system 11 in the embodiment of the present application can perform a voltage step-up conversion on the power supply voltage of the DC power supply, so as to charge the high-voltage power battery 12, which is conducive to improving the convenience of charging the high-voltage power battery 12. At the same time, the embodiment of the present application implements the charging system 11 by reusing the N bridge arms in the MCU 111, which is also conducive to reducing the space and cost occupied by the charging system 11.

[0137] It is understandable that the power supply voltage provided by the DC power supply may also be adapted to the power battery 12. For example, the charging voltage range of the power battery 12 is 700-1000V, and the power supply voltage of the DC power supply (charging pile) is 800V. In this case, there is no need to perform a step-up conversion on the power supply voltage.

[0138] To be compatible with this scenario, Figure 7 As shown, the charging system 11 provided in the embodiment of the present application may further include a switch K1. The first end of the switch K1 is connected to the second battery end, and the second end of the switch K1 is connected to the second power supply end. The MCU 111 may control the on and off of the switch K1. Specifically, the MCU 111 may turn on the switch K1 when the power supply voltage is within the charging voltage range of the power battery 12, and turn off the switch K1 when the power supply voltage is outside the charging voltage range of the power battery 12.

[0139] Among them, the scenario where the power supply voltage is within the charging voltage range of the power battery 12 may be a scenario where the power supply voltage is equal to the minimum charging voltage of the power battery 12, a scenario where the power supply voltage is equal to the maximum charging voltage of the power battery 12, or a scenario where the power supply voltage is greater than the minimum charging voltage of the power battery 12 and less than the maximum charging voltage of the power battery 12. The scenario where the power supply voltage is outside the charging voltage range of the power battery 12 may be a scenario where the power supply voltage is less than the minimum charging voltage of the power battery 12, or a scenario where the power supply voltage is greater than the maximum charging voltage of the power battery 12.

[0140] like Figure 7As shown, when the power battery 12 is charged, the switch K5 is turned on by default. When the switch K1 is turned on, the power battery 12 can be directly connected to the DC power supply, so it can directly receive the power supply voltage provided by the DC power supply to complete charging. Therefore, the MCU 111 can turn on the switch K1 when the power supply voltage is within the charging voltage range of the power battery 12.

[0141] When switch K1 is turned off, Figure 7 The charging system 11 shown is equivalent to Figure 3 In the charging system 11 shown, the MCU 111 can perform a voltage boost conversion on the power supply voltage, which will not be described in detail.

[0142] In one possible implementation, Figure 3 As shown, the charging system 11 may further include a filter capacitor C1, one end of the filter capacitor C1 is connected to the first battery terminal, and the other end of the filter capacitor C1 is connected to the second battery terminal. When charging the power battery 12, the filter capacitor C1 may filter the first output voltage.

[0143] Similar, such as Figure 3 As shown, the charging system 11 may further include a filter capacitor C2, one end of the filter capacitor C2 is connected to the first power supply terminal, and the other end of the filter capacitor C2 is connected to the second power supply terminal. When charging the power battery 12, the filter capacitor C2 may filter the received power supply voltage.

[0144] Embodiment 2

[0145] With the development of charging and discharging technology of electric vehicles 10, more and more electric vehicles 10 can also support the discharge function, that is, the electric vehicle 10 supplies power to a DC load. In some scenarios, the DC load can be another electric vehicle. For example, Figure 3 As shown, the first power supply terminal of the charging system 11 can also be connected to the positive electrode of the DC load, and the second power supply terminal of the charging system 11 can also be connected to the negative electrode of the DC load.

[0146] The power battery 12 can output a battery voltage to the charging system 11. When the battery voltage of the power battery 12 is greater than the maximum operating voltage of the DC load, the charging system 11 can step down the battery voltage to obtain a second output voltage adapted to the DC load, and output the second output voltage to the DC load through the first power supply terminal and the second power supply terminal. When the DC load is another electric vehicle, the operating voltage range of the DC load can be understood as the charging voltage range of the power battery in the other electric vehicle.

[0147] The lower limit of the working voltage range of the DC load is the minimum working voltage, which can be understood as the minimum value of the working voltage that the DC load can adapt to. The upper limit of the working voltage range of the DC load is the maximum working voltage, which can be understood as the maximum value of the working voltage that the DC load can adapt to.

[0148] For example, if the battery voltage of the power battery 12 is 800V and the working voltage range of the DC load is 400-600V, the MCU 111 can step down the battery voltage to obtain a second output voltage within the working voltage range. The charging system 11 outputs the second output voltage to the DC load, thereby providing a matching working voltage for the DC load.

[0149] Next, Figure 3 Taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the process of the boost conversion is further illustrated. It can be understood that at this time, the switches K2 to K5 are turned on, and no further description is given. When the battery voltage is bucked, it mainly includes the following two stages:

[0150] Phase 1: Charging of inductor L1

[0151] MCU111 turns on the switch tube T4, while the switch tube T3 remains off. Figure 8 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the DC load, the inductor L1 and the switch tube T4, it flows back to the negative electrode of the power battery 12. During this stage, the inductor L1 is charged. The second output voltage output by the charging system 11 is the difference between the battery voltage and the voltage of the inductor L1. Obviously, the second output voltage is less than the battery voltage, so the charging system 11 can achieve a step-down conversion of the battery voltage.

[0152] Phase 2: Inductor L1 discharges

[0153] MCU111 can turn off the switch tube T4, and the charging circuit of the inductor L1 is turned off. Due to the freewheeling characteristic of the inductor, the inductor L1 starts to discharge. Fig. 9 As shown, the current is output from the end of the inductor L1 close to the switch tube T3, and flows back to the end of the inductor L1 close to the second power supply end after being transmitted through the diode in the switch tube T3 and the DC load. In this process, the second output voltage of the charging system 11 is the voltage of the inductor L1. Obviously, the voltage of the inductor L1 is lower than the battery voltage, so the charging system 11 can achieve a step-down conversion of the battery voltage.

[0154] Understandably, Figure 6In the charging system 11 shown, the MCU 111 can also synchronously control multiple bridge arms to perform boost conversion. For example, the MCU 111 can synchronously control the on and off of the switch tubes T2, T4, and T6 to synchronously charge and discharge the inductors L1-1 to L1-3. In this case, it is equivalent to three inductors working in parallel, thereby supporting voltage conversion in high-power scenarios.

[0155] It should be pointed out that if Figure 7 The charging system 11 shown is also suitable for step-down conversion of the battery voltage. When the battery voltage is within the operating voltage range of the DC load, the MCU 111 can turn on the switch K1 so that the power battery 12 directly supplies power to the DC load. When the battery voltage is outside the operating voltage range of the DC load, the MCU 111 can turn off the switch K1 so that the MCU 111 can perform voltage conversion on the battery voltage. The details are not repeated here.

[0156] Among them, the scenario where the battery voltage is within the operating voltage range of the DC load can be a scenario where the battery voltage is equal to the minimum operating voltage of the DC load, a scenario where the battery voltage is equal to the maximum operating voltage of the DC load, or a scenario where the battery voltage is greater than the minimum operating voltage of the DC load and less than the maximum operating voltage of the DC load. The scenario where the battery voltage is outside the operating voltage range of the DC load can be a scenario where the battery voltage is less than the minimum operating voltage of the DC load, or a scenario where the battery voltage is greater than the maximum operating voltage of the DC load.

[0157] Embodiment 3

[0158] As mentioned above, there are both low-voltage charging piles and high-voltage charging piles in the current market. The electric vehicle 10 can be equipped with both high-voltage power batteries and low-voltage power batteries. Therefore, it will also be a common scenario for a high-voltage charging pile to charge a low-voltage power battery.

[0159] In view of this, the embodiment of the present application further provides a charging system 11, and the connection relationship between the charging system 11 and the DC power supply and the power battery 12 is the same as that in the above embodiment, which will not be described in detail. When the power supply voltage of the DC power supply is greater than the maximum charging voltage of the power battery 12, the charging system 11 can step down the power supply voltage. When the power supply voltage of the DC power supply is less than the minimum charging voltage of the power battery 12, the charging system 11 can step up the power supply voltage. Therefore, the charging system 11 can provide the power battery 12 with a first output voltage that is compatible with it.

[0160] For example, Fig.10As shown, the charging system 11 in the embodiment of the present application may include an MCU 111 and an inductor L1, and the connection relationship between the N bridge arms in the MCU 111 and the inductor L1 is not repeated. In addition, the charging system 11 may also include a switch K1 and a switch K2. Among them, the first end of the switch K1 is connected to the second battery terminal of the charging system 11, and the second end of the switch K1 is connected to the second power supply terminal. The switch K2 is a single-pole double-throw switch, wherein the first end of the switch K2 is connected to the first battery terminal, the second end a of the switch K2 is connected to one end of the inductor L1, and the third end b of the switch K2 is connected to the first power supply terminal.

[0161] It should be noted that the switch K2 can be independently provided with the power battery 12. In this case, the first end of the switch K2 can be understood as the first battery end of the charging system 11. It can be understood that the switch K2 can also be integrated with the power battery 12 in the power battery pack. In this case, it can be considered that the charging system 11 provided in the embodiment of the present application includes two first battery ends, one of which is connected to the second end a of the switch K2, and the other first battery end is connected to the third end b of the switch K2.

[0162] Next, Fig.10 Taking as an example, the step-down conversion and step-up conversion of the power supply voltage are respectively explained.

[0163] 1. Buck conversion

[0164] During the step-down conversion process, the MCU 111 can turn on the switch K1, and turn on the first end and the second end a of the switch K2. The circuit state can be as follows: Fig.11 It should be noted that in some scenarios, switches K3 to K5 may also be provided in the charging system 11. In this case, switches K4 and K5 should be kept turned on, and switch K3 should be kept turned off. Fig.11 In the circuit state shown, taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the step-down conversion process mainly includes:

[0165] Phase 1: Charging of inductor L1

[0166] MCU111 turns on the switch tube T3 to charge the inductor L1. Fig.12 As shown, the current is output from the positive electrode of the DC power supply, and after being transmitted through the switch tube T3, the inductor L1, the switch K2, and the power battery 12, it flows back to the negative electrode of the DC power supply, thereby forming a charging circuit to charge the inductor L1. In this process, the first output voltage of the charging system 11 is the difference between the power supply voltage and the voltage of the inductor L1. Obviously, the first output voltage is less than the power supply voltage, so the charging system 11 can achieve step-down conversion.

[0167] Phase 2: Inductor L1 discharges

[0168] MCU111 turns off the switch tube T3 to discharge the inductor L1. Specifically, after MCU111 turns off the switch tube T3, the charging circuit is turned off. Due to the freewheeling characteristics of the inductor, the inductor L1 is discharged. Fig.13 As shown, the current is output from the end of the inductor L1 close to the second power supply end, and after being transmitted through the switch K2, the power battery 12 and the diode in the switch tube T4, it flows back to the end of the inductor L1 close to the switch tube T4. In this process, the first output voltage of the charging system 11 is the voltage of the inductor L1. Obviously, the first output voltage is less than the power supply voltage, so the charging system 11 can realize step-down conversion of the power supply voltage.

[0169] 2. Boost Conversion

[0170] like Fig.10 As shown, the charging system 11 may further include a switch K3. The first end of the switch K3 is connected to the connection point of the motor windings N1 to N3, and the second end of the switch K3 is connected to the second power supply terminal. During the step-up conversion process, the MCU 111 may turn on the first end and the third end b of the switch K2, turn on the switch K3, and turn off the switch K1. The circuit state may be as follows: Fig.14 As shown. Fig.14 It can be seen that the circuit state in this case is equivalent to Figure 3 The charging system 11 shown in the figure can therefore refer to the boost conversion process provided in the above-mentioned embodiment 1, which will not be described in detail.

[0171] also, Fig.10 The charging system 11 shown can also support voltage conversion in a buck-boost mode for the power supply voltage. Specifically:

[0172] Buck-Boost

[0173] When performing buck-boost conversion on the power supply voltage, the MCU 111 can turn on the first terminal and the second terminal a of the switch K2, and turn on the switch K3. The circuit state can be as follows: Fig.15 Based on Fig.15 The circuit state shown, buck-boost conversion mainly includes the following two stages:

[0174] Phase 1: Charging of inductor L1

[0175] MCU111 turns on the switch tube T3 to charge the inductor L1. Fig.16 As shown, the current is output from the positive electrode of the DC power supply, transmitted through the switch tube T3 and the inductor L1, and then flows back to the negative electrode of the DC power supply, thereby forming a charging loop of the inductor L1 to charge the inductor L1.

[0176] Phase 2: Inductor L1 discharges

[0177] MCU111 turns off the switch tube T3 to discharge the inductor L1. Fig.17 As shown, the current is output from the end of the inductor L1 close to the second power supply end, and after being transmitted through the switch K2, the power battery 12 and the diode in the switch tube T4, it flows back to the end of the inductor L1 close to the switch tube T4. It can be seen that the first output voltage of the charging system 11 is equal to the voltage of the inductor L1. By controlling the charging time of the inductor L1 in the first stage, the MCU111 can control the voltage of the inductor L1, thereby controlling the magnitude of the first output voltage, which may be greater than the power supply voltage or less than the power supply voltage.

[0178] Similar to the first embodiment, when the power supply voltage of the DC power supply is within the charging voltage range of the power battery 12, the MCU 111 can also turn on the first end and the third end b of the switch K2, and turn on the switch K1, so that the power battery 12 can directly receive the power supply voltage, thereby completing the charging. The specific implementation can refer to the first embodiment, which will not be described in detail.

[0179] Embodiment 4

[0180] It should be pointed out that Fig.10 The charging system 11 shown can also support the discharge function of the electric vehicle 10. When the electric vehicle 10 is discharging, the connection relationship between the charging system 11, the power battery 12 and the DC load is similar to that in the second embodiment, which will not be described in detail.

[0181] The difference from the second embodiment is that: Fig.10 The provided charging system 11 can not only step down the battery voltage, but also step up the battery voltage, so that the battery voltage output by the high-voltage power battery and the low-voltage power battery can adapt to DC loads with different operating voltage ranges.

[0182] Next, Fig.10 Taking as an example, the step-up conversion and step-down conversion of the battery voltage are respectively explained.

[0183] 1. Boost Conversion

[0184] During the boost conversion process, the MCU 111 can turn on the switch K1, and turn on the first end and the second end a of the switch K2. The circuit state can be as follows: Fig.11 Based on Fig.11 In the circuit state shown, taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the boost conversion process mainly includes:

[0185] Phase 1: Charging of inductor L1

[0186] MCU111 turns on the switch tube T4 to charge the inductor L1. Fig.18 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the switch K2, the inductor L1 and the switch tube T4, it flows back to the negative electrode of the power battery 12, thereby forming a charging loop to charge the inductor L1.

[0187] Phase 2: Inductor L1 discharges

[0188] MCU111 turns off the switch tube T4 to discharge the inductor L1. After MCU111 turns off the switch tube T4, the charging circuit is turned off. Due to the freewheeling characteristics of the inductor, the inductor L1 is discharged. Fig.19 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the switch K2, the inductor L1, the diode in the switch tube T3 and the DC load, it flows back to the negative electrode of the power battery 12. In this process, the second output voltage of the charging system 11 is the sum of the battery voltage of the power battery 12 and the voltage of the inductor L1. Obviously, the second output voltage is greater than the battery voltage, so the charging system 11 can achieve a boost conversion of the battery voltage.

[0189] 2. Buck Conversion

[0190] like Fig.10 As shown, the charging system 11 may further include a switch K3. The first end of the switch K3 is connected to the connection point of the motor windings N1 to N3, and the second end of the switch K3 is connected to the second power supply terminal. During the step-down conversion process, the MCU 111 may turn on the first end and the third end b of the switch K2, turn on the switch K3, and turn off the switch K1. The circuit state may be as follows: Fig.14 As shown. Fig.14 It can be seen that the circuit state in this case is equivalent to Figure 3 The charging system 11 shown can therefore refer to the step-down conversion process provided in the above-mentioned second embodiment, which will not be described in detail.

[0191] also, Fig.10 The charging system 11 shown can also support buck-boost mode voltage conversion of the battery voltage. Specifically:

[0192] Buck-Boost

[0193] When performing buck-boost conversion on the battery voltage, the MCU 111 can turn on the first terminal and the second terminal a of the switch K2, and turn on the switch K3. The circuit state can be as follows: Fig.15 Based on Fig.15 The circuit state shown, buck-boost conversion mainly includes the following two stages:

[0194] Phase 1: Charging of inductor L1

[0195] MCU111 turns on the switch tube T4 to charge the inductor L1. Fig. 20 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the switch K2, the inductor L1 and the switch tube T4, it flows back to the negative electrode of the power battery 12, thereby forming a charging loop of the inductor L1.

[0196] Phase 2: Inductor L1 discharges

[0197] MCU111 turns off the switch tube T4 to discharge the inductor L1. Fig.21 As shown, the current is output from one end of the inductor L1 close to the switch tube T3, and after being transmitted through the diode in the switch tube T3 and the DC load, it flows back to the end of the inductor L1 close to the second power supply end. It can be seen that the second output voltage of the charging system 11 is equal to the voltage of the inductor L1. By controlling the charging time of the inductor L1 in the first stage, the MCU111 can control the voltage of the inductor L1, thereby controlling the magnitude of the second output voltage, which may be greater than the battery voltage or less than the battery voltage.

[0198] Similar to the second embodiment, when the battery voltage of the power battery 12 is within the operating voltage range of the DC load, the MCU 111 can also turn on the first end and the third end b of the switch K2, and turn on the switch K1, so that the power battery 12 can directly power the DC load. The specific implementation can refer to the second embodiment, which will not be described in detail.

[0199] Embodiment 5

[0200] In the third and fourth embodiments, the inductor L1 is connected to the second power supply terminal. Based on a similar concept, the inductor L1 can also be connected to the first power supply terminal. In this case, the charging system 11 can be as follows: Fig. 22 shown.

[0201] The charging system 11 further includes a switch K5 and a switch K6. The switch K5 is a single-pole double-throw switch, wherein a first end of the switch K5 is connected to the second battery end, a second end a of the switch K5 is connected to the low potential end of the N bridge arms, a third end b of the switch K5 is connected to one end of the inductor L1, a second end of the switch K6 is connected to the second power supply end, a first end of the switch K6 is connected to the first battery end, and a second end of the switch K6 is connected to the first power supply end.

[0202] It should be noted that the switch K5 can be independently provided with the power battery 12. In this case, the first end of the switch K5 can be understood as the second battery end of the charging system 11. It can be understood that the switch K5 can also be integrated with the power battery 12 in the power battery pack. In this case, it can be considered that the charging system 11 provided in the embodiment of the present application includes two second battery ends, one of which is connected to the second end a of the switch K5, and the other second battery end is connected to the third end b of the switch K5.

[0203] Next, Fig. 22 Taking as an example, the step-down conversion and step-up conversion of the power supply voltage are respectively explained.

[0204] 1. Buck conversion

[0205] When the power supply voltage is greater than the maximum charging voltage, the MCU111 can perform a step-down conversion on the power supply voltage. During the step-down conversion process, the MCU111 can turn on the switch K6, and turn on the first end and the third end b of the switch K5. The circuit state can be as follows: Fig.23 It should be noted that in some scenarios, switches K2 to K4 may also be provided in the charging system 11. In this case, switches K2 and K3 should be kept turned on, and switch K4 should be kept turned off. Fig.23 In the circuit state shown, taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the step-down conversion process mainly includes:

[0206] Phase 1: Charging of inductor L1

[0207] MCU111 turns on the switch tube T4 to charge the inductor L1. Fig.24 As shown, the current is output from the positive electrode of the DC power supply, and after being transmitted through the power battery 12, the switch K5, the inductor L1 and the switch tube T4, it flows back to the negative electrode of the DC power supply, thereby forming a charging circuit to charge the inductor L1. In this process, the first output voltage of the charging system 11 is the difference between the power supply voltage and the voltage of the inductor L1. Obviously, the first output voltage is less than the power supply voltage, so the charging system 11 can achieve step-down conversion.

[0208] Phase 2: Inductor L1 discharges

[0209] MCU111 turns off the switch tube T4 to discharge the inductor L1. Turn off the second switch tube to discharge the inductor L1. Specifically, after MCU111 turns off the switch tube T4, the charging circuit is turned off. Due to the freewheeling characteristics of the inductor, the inductor L1 is discharged. Fig.25As shown, the current is output from the end of the inductor L1 close to the switch tube T3, and after being transmitted through the diode in the switch tube T3, the power battery 12, and the switch K5, it flows back to the end of the inductor L1 close to the first power supply end. In this process, the first output voltage of the charging system 11 is the voltage of the inductor L1. Obviously, the first output voltage is less than the power supply voltage, so the charging system 11 can realize step-down conversion of the power supply voltage.

[0210] 2. Boost Conversion

[0211] like Fig. 22 As shown, the charging system 11 may further include a switch K4. The first end of the switch K4 is connected to the connection end of the N motor windings, and the second end of the switch K4 is connected to the first power supply end. During the boost conversion process, the MCU 111 may turn on the first end and the second end a of the switch K5, turn on the switch K4 and turn off the switch K6, and the circuit state may be as follows Fig.26 As shown. Fig.26 It can be seen that the circuit state in this case is equivalent to Figure 3 The charging system 11 shown in the figure can therefore refer to the boost conversion process provided in the above-mentioned embodiment 1, which will not be described in detail.

[0212] also, Fig. 22 The charging system 11 shown can also support voltage conversion in a buck-boost mode for the power supply voltage. Specifically:

[0213] Buck-Boost

[0214] When performing buck-boost conversion on the power supply voltage, the MCU 111 can turn on the first terminal and the third terminal b of the switch K5, and turn on the switch K4. The circuit state can be as follows: Fig. 27 Based on Fig. 27 The circuit state shown, buck-boost conversion mainly includes the following two stages:

[0215] Phase 1: Charging of inductor L1

[0216] MCU111 turns on the switch tube T4 to charge the inductor L1. Fig.28 As shown, the current is output from the positive electrode of the DC power supply, and after being transmitted through the switch tube inductor L1 and the switch tube T4, it flows back to the negative electrode of the DC power supply, thereby forming a charging loop for the inductor L1.

[0217] Phase 2: Inductor L1 discharges

[0218] MCU111 turns off the switch tube T3 to discharge the inductor L1. Fig.29As shown, the current is output from the end of the inductor L1 close to the switch tube T3, and after being transmitted through the diode in the switch tube T3, the power battery 12 and the switch K5, it flows back to the end of the inductor L1 close to the first power supply end. It can be seen that the first output voltage of the charging system 11 is equal to the voltage of the inductor L1. By controlling the charging time of the inductor L1 in the first stage, the MCU111 can control the voltage of the inductor L1, thereby controlling the magnitude of the first output voltage, which may be greater than the power supply voltage or less than the power supply voltage.

[0219] Similar to the first embodiment, when the power supply voltage of the DC power supply is within the charging voltage range of the power battery 12, the MCU 111 can also turn on the first end and the second end a of the switch K5, and turn on the switch K6, so that the power battery 12 can directly receive the power supply voltage, thereby completing the charging. The specific implementation can refer to the first embodiment, which will not be described in detail.

[0220] Embodiment 6

[0221] It should be pointed out that Fig. 22 The charging system 11 shown can also not only step down the battery voltage but also step up the battery voltage so that the battery voltage output by the high-voltage power battery and the low-voltage power battery can adapt to DC loads with different operating voltage ranges.

[0222] Next, Fig. 22 Taking as an example, the step-up conversion and step-down conversion of the battery voltage are respectively explained.

[0223] 1. Boost Conversion

[0224] During the boost conversion process, the MCU 111 can turn on the switch K6, and turn on the first end and the third end b of the switch K5. The circuit state can be as follows: Fig.23 Based on Fig.23 In the circuit state shown, taking the bridge arm 2 including the switch tube T3 and the switch tube T4 as an example, the boost conversion process mainly includes:

[0225] Phase 1: Charging of inductor L1

[0226] MCU111 turns on the switch tube T3 to charge the inductor L1. Fig.30 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the switch tube T3, the inductor L1 and the switch K5, it flows back to the negative electrode of the power battery 12, thereby forming a charging loop to charge the inductor L1.

[0227] Phase 2: Inductor L1 discharges

[0228] MCU111 turns off the switch tube T3 to discharge the inductor L1. After MCU111 turns off the switch tube T3, the charging circuit is turned off. Due to the freewheeling characteristics of the inductor, the inductor L1 is discharged. Fig.32 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the DC load, the diode in the switch tube T4, the inductor L1 and the switch tube K5, it flows back to the negative electrode of the power battery 12. In this process, the second output voltage of the charging system 11 is the sum of the battery voltage of the power battery 12 and the voltage of the inductor L1. Obviously, the second output voltage is greater than the battery voltage, so the charging system 11 can achieve a boost conversion of the battery voltage.

[0229] 2. Buck Conversion

[0230] like Fig. 22 The charging system 11 may further include a switch K4. The first end of the switch K4 is connected to the connection point of the N motor windings, and the second end of the switch K4 is connected to the first power supply terminal. During the step-down conversion process, the MCU 111 may turn on the first end and the second end a of the switch K5, turn on the switch K4, and turn off the switch K6. The circuit state may be as follows: Fig.26 As shown. Fig.26 It can be seen that the circuit state in this case is equivalent to Figure 3 The charging system 11 shown can therefore refer to the step-down conversion process provided in the above-mentioned second embodiment, which will not be described in detail.

[0231] also, Fig. 22 The charging system 11 shown can also support buck-boost mode voltage conversion of the battery voltage. Specifically:

[0232] Buck-Boost

[0233] When performing buck-boost conversion on the battery voltage, the MCU 111 can turn on the first terminal and the third terminal b of the switch K5, and turn on the switch K4. The circuit state can be as follows: Fig. 27 Based on Fig. 27 The circuit state shown, buck-boost conversion mainly includes the following two stages:

[0234] Phase 1: Charging of inductor L1

[0235] MCU111 turns on the switch tube T3 to charge the inductor L1. Fig.32 As shown, the current is output from the positive electrode of the power battery 12, and after being transmitted through the switch tube T3, the inductor L1 and the switch K5, it flows back to the negative electrode of the power battery 12, thereby forming a charging loop of the inductor L1.

[0236] Phase 2: Inductor L1 discharges

[0237] MCU111 turns off the switch tube T3 to discharge the inductor L1. Fig.33 As shown, the current is output from the end of the inductor L1 close to the first power supply end, and after being transmitted through the DC load and the diode in the switch tube T4, it flows back to the end of the inductor L1 close to the switch tube T4. It can be seen that the second output voltage of the charging system 11 is equal to the voltage of the inductor L1. By controlling the charging time of the inductor L1 in the first stage, the MCU111 can control the voltage of the inductor L1, thereby controlling the magnitude of the second output voltage, which may be greater than the battery voltage or less than the battery voltage.

[0238] Similar to the second embodiment, when the battery voltage of the power battery 12 is within the operating voltage range of the DC load, the MCU 111 can also turn on the first end and the second end a of the switch K5, and turn on the switch K6, so that the power battery 12 can directly power the DC load. The specific implementation can refer to the second embodiment, which will not be described in detail.

[0239] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A charging system, characterized in that: The invention comprises a motor controller MCU, a first switch, a second switch, a first inductor and a third switch, wherein the MCU comprises N bridge arms, where N is an integer greater than or equal to 1, wherein: The high potential ends of the N bridge arms are connected to a first power supply end and a first battery end of the charging system, the first power supply end is used to connect to the positive electrode of a DC power supply, the first battery end is used to connect to the positive electrode of a power battery, the DC power supply is used to output a power supply voltage, and the power battery is used to receive a first output voltage of the charging system; The low potential ends of the N bridge arms are connected to the second battery end of the charging system, and the second battery end is used to connect the negative electrode of the power battery; One end of the third switch is connected to the second power supply end, the second power supply end is used to connect the negative electrode of the DC power supply, the other end of the third switch is connected to one end of the first inductor, the other end of the first inductor is connected to the middle point of the first bridge arm, the first bridge arm is any bridge arm among the N bridge arms; the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is respectively connected to the first battery end and the first power supply end, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point is located between the first switch tube and the second switch tube; A first end of the first switch is connected to the second battery terminal, a second end of the first switch is connected to the second power supply terminal, a first end of the second switch is connected to the first battery terminal, a second end of the second switch is connected to one end of the first inductor, and a third end of the second switch is connected to the first power supply terminal; The first bridge arm, the first inductor, the first switch, the second switch and the third switch constitute a voltage conversion circuit, and the MCU is used for: When the DC power supply voltage is less than the minimum charging voltage of the power battery, the first end and the third end of the second switch are turned on, and the third switch is turned on, the first switch tube is turned on to charge the first inductor and the first switch tube is turned off to discharge the first inductor, the DC power supply voltage and the first inductor voltage are superimposed on each other by the voltage conversion circuit to perform a voltage boost conversion, and the voltage after the voltage boost conversion is output to the power battery as the first output voltage, and the first output voltage is not less than the minimum charging voltage; When the power supply voltage is greater than the maximum charging voltage of the power battery, the first switch is turned on, and the first end and the second end of the second switch are turned on, the first switch tube is turned on to charge the first inductor and the first switch tube is turned off to discharge the first inductor, the power supply voltage is stepped down by the voltage conversion circuit, and the stepped-down power supply voltage is output to the power battery as the first output voltage, and the first output voltage is not greater than the maximum charging voltage.

2. The charging system according to claim 1, characterized in that: The MCU is also used for: When the power supply voltage is within the charging voltage range of the power battery, turning on the first switch; When the power supply voltage is outside the charging voltage range of the power battery, the first switch is turned off.

3. The charging system according to claim 1 or 2, characterized in that: The charging system includes N first inductors and N third switches, one end of the N third switches is connected to the second power supply end, the other end of the N third switches is connected to one end of the N first inductors in a one-to-one correspondence, and the other end of the N first inductors is connected to the middle points of the N bridge arms in a one-to-one correspondence; The N third switches are used to: When receiving the power supply voltage, the connection between the N first inductors and the second power supply terminal is turned on, or when stopping receiving the power supply voltage, the connection between the N first inductors and the second power supply terminal is turned off to end the freewheeling of the first inductor.

4. The charging system according to claim 1 or 2, characterized in that: When the power supply voltage is less than the minimum charging voltage, the MCU is specifically configured to: Turning on the first end and the third end of the second switch, turning on the third switch, and turning off the first switch; Turning on the first switch tube to charge the first inductor; The first switch tube is turned off to discharge the first inductor.

5. The charging system according to claim 1 or 2, characterized in that: The MCU is also used for: When the power supply voltage is within the charging voltage range of the power battery, the first end and the third end of the second switch are turned on, and the first switch is turned on.

6. A charging system, characterized in that: The invention comprises a motor controller MCU, a first switch, a second switch, a first inductor and a third switch, wherein the MCU comprises N bridge arms, where N is an integer greater than or equal to 1, wherein: The high potential ends of the N bridge arms are connected to a first power supply end and a first battery end of the charging system, the first power supply end is used to connect the positive electrode of the DC load, the first battery end is used to connect the positive electrode of the power battery, the DC load is used to receive the second output voltage of the charging system, and the power battery is used to output the battery voltage to the charging system; The low potential ends of the N bridge arms are connected to the second battery end of the charging system, and the second battery end is used to connect the negative electrode of the power battery; One end of the third switch is connected to the second power supply end, the second power supply end is used to connect the negative electrode of the DC load, the other end of the third switch is connected to one end of the first inductor in a one-to-one correspondence, the other end of the first inductor is connected to the middle point of the first bridge arm, the first bridge arm is any bridge arm among the N bridge arms; the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is respectively connected to the first battery end and the first power supply end, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point is located between the first switch tube and the second switch tube; A first end of the first switch is connected to the second battery terminal, a second end of the first switch is connected to the second power supply terminal, a first end of the second switch is connected to the first battery terminal, a second end of the second switch is connected to one end of the first inductor, and a third end of the second switch is connected to the first power supply terminal; The first bridge arm, the first inductor, the first switch, the second switch and the third switch constitute a voltage conversion circuit, and the MCU is used for: When the battery voltage is greater than the maximum operating voltage of the DC load, the first end and the third end of the second switch are turned on, the third switch is turned on, the second switch tube is turned on to charge the first inductor and the second switch tube is turned off to discharge the first inductor, the battery voltage is stepped down by the voltage conversion circuit, and the stepped-down battery voltage is output as the second output voltage to the DC load, and the second output voltage is not greater than the maximum operating voltage; When the battery voltage is less than the minimum operating voltage of the DC load, the first switch is turned on, and the first end and the second end of the second switch are turned on, the second switch tube is turned on to charge the first inductor and the second switch tube is turned off to discharge the first inductor, the battery voltage is superimposed on the first inductor voltage through the voltage conversion circuit to perform a boost conversion, and the boosted voltage is output to the DC load as the second output voltage, and the second output voltage is not less than the minimum operating voltage.

7. The charging system according to claim 6, characterized in that: The MCU is also used for: When the battery voltage is within the operating voltage range of the DC load, turning on the first switch; When the battery voltage is outside the operating voltage range of the DC load, the first switch is turned off.

8. The charging system according to claim 6 or 7, characterized in that: The charging system includes N first inductors and N third switches, one end of the N third switches is connected to the second power supply end, the other end of the N third switches is connected to one end of the N first inductors in a one-to-one correspondence, and the other end of the N first inductors is connected to the N bridge arms in a one-to-one correspondence; The N third switches are used to: When the second output voltage is output, the connection between the N first inductors and the second power supply terminal is turned on, or when the second output voltage is stopped, the connection between the N first inductors and the second power supply terminal is turned off to end the freewheeling of the first inductors.

9. The charging system according to claim 6 or 7, characterized in that: When the battery voltage is greater than the maximum operating voltage, the MCU is specifically configured to: Turning on the first end and the third end of the second switch, turning on the third switch, and turning off the first switch; Turning on the second switch tube to charge the first inductor; The second switch tube is turned off to discharge the first inductor.

10. The charging system according to claim 6 or 7, characterized in that: The MCU is also used for: When the battery voltage is within the operating voltage range of the power battery, the first end and the third end of the second switch are turned on, and the first switch is turned on.

11. A charging system, characterized in that: The invention comprises a motor controller MCU, a first inductor, a fourth switch, a fifth switch and a sixth switch, wherein the MCU comprises N bridge arms, where N is an integer greater than or equal to 1, wherein: The high potential ends of the N bridge arms are connected to a first battery end of the charging system, the first battery end is used to connect to the positive electrode of a power battery, and the power battery is used to receive a first output voltage of the charging system; The low potential ends of the N bridge arms are connected to the second battery end and the second power supply end of the charging system, the second battery end is used to connect the negative electrode of the power battery, and the second power supply end is used to connect the negative electrode of the DC power supply, and the DC power supply is used to output the power supply voltage; The first end of the fourth switch is connected to one end of the first inductor, the second end of the fourth switch is connected to the first power supply end, the other end of the first inductor is connected to the middle point of the first bridge arm, the first power supply end is used to connect the positive electrode of the DC power supply, and the first bridge arm is any bridge arm among the N bridge arms; the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is respectively connected to the first battery end and the first power supply end, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point is located between the first switch tube and the second switch tube; A first end of the fifth switch is connected to the second battery terminal, a second end of the fifth switch is connected to the low potential ends of the N bridge arms, a third end of the fifth switch is connected to one end of the first inductor, a first end of the sixth switch is connected to the first battery terminal, and a second end of the sixth switch is connected to the first power supply terminal; The first bridge arm, the first inductor, the fourth switch, the fifth switch and the sixth switch constitute a voltage conversion circuit, and the MCU is used for: When the power supply voltage is less than the minimum charging voltage of the power battery, the first end and the third end of the fifth switch are turned on, the fourth switch is turned on, the second switch tube is turned on to charge the first inductor and the second switch tube is turned off to discharge the first inductor, the power supply voltage and the first inductor voltage are superimposed on each other by the voltage conversion circuit to perform a voltage boost conversion, and the voltage after the voltage boost conversion is output to the power battery as a first output voltage, and the first output voltage is not less than the minimum charging voltage; When the power supply voltage is greater than the maximum charging voltage of the power battery, the sixth switch is turned on, and the first end and the third end of the fifth switch are turned on, the second switch tube is turned on to charge the first inductor and the second switch tube is turned off to discharge the first inductor, the power supply voltage is stepped down by the voltage conversion circuit, and the stepped-down power supply voltage is output to the power battery as the first output voltage, and the first output voltage is not greater than the minimum charging voltage.

12. The charging system according to claim 11, characterized in that: When the power supply voltage is less than the minimum charging voltage, the MCU is specifically configured to: Turning on the first end and the second end of the fifth switch, turning on the fourth switch, and turning off the sixth switch; Turning on the second switch tube to charge the first inductor; The second switch tube is turned off to discharge the first inductor.

13. The charging system according to claim 11 or 12, characterized in that: The MCU is also used for: When the power supply voltage is within the charging voltage range of the power battery, the first end and the second end of the fifth switch are turned on, and the sixth switch is turned on.

14. A charging system, characterized in that: The invention comprises a motor controller MCU, a first inductor, a fourth switch, a fifth switch and a sixth switch, wherein the MCU comprises N bridge arms, where N is an integer greater than or equal to 1, wherein: The high potential ends of the N bridge arms are connected to a first battery end of the charging system, the first battery end is used to connect to the positive electrode of a power battery, and the power battery is used to output a battery voltage to the charging system; The low potential ends of the N bridge arms are connected to a second battery end and a second power supply end of the charging system, the second battery end is used to connect the negative electrode of the power battery, the second power supply end is used to connect the negative electrode of a DC load, and the DC load is used to receive a second output voltage of the charging system; The first end of the fourth switch is connected to one end of the first inductor, the second end of the fourth switch is connected to the first power supply end, the other end of the first inductor is connected to the middle point of the first bridge arm, the first power supply end is used to connect the positive electrode of the DC load, and the first bridge arm is any bridge arm among the N bridge arms; the first bridge arm includes a first switch tube and a second switch tube, wherein the first electrode of the first switch tube is respectively connected to the first battery end and the first power supply end, the second electrode of the first switch tube is connected to the first electrode of the second switch tube, and the middle point is located between the first switch tube and the second switch tube; A first end of the fifth switch is connected to the second battery terminal, a second end of the fifth switch is connected to the low potential ends of the N bridge arms, a third end of the fifth switch is connected to one end of the first inductor, a first end of the sixth switch is connected to the first battery terminal, and a second end of the sixth switch is connected to the first power supply terminal; The first bridge arm, the first inductor, the fourth switch, the fifth switch and the sixth switch constitute a voltage conversion circuit, and the MCU is used for: When the battery voltage is greater than the maximum operating voltage of the DC load, the first end and the third end of the fifth switch are turned on, the fourth switch is turned on, the first switch tube is turned on to charge the first inductor and the first switch tube is turned off to discharge the first inductor, the battery voltage is stepped down by the voltage conversion circuit, and the stepped-down battery voltage is output as the second output voltage to the DC load, and the second output voltage is not greater than the maximum operating voltage; When the battery voltage is less than the minimum operating voltage of the DC load, the sixth switch is turned on, and the first end and the third end of the fifth switch are turned on, the first switch tube is turned on to charge the first inductor and the first switch tube is turned off to discharge the first inductor, the battery voltage is superimposed on the first inductor voltage through the voltage conversion circuit to perform a boost conversion, and the boosted voltage is output to the DC load as the second output voltage, and the second output voltage is not less than the minimum operating voltage.

15. The charging system according to claim 14, characterized in that: When the battery voltage is greater than the maximum operating voltage, the MCU is specifically configured to: Turning on the first end and the second end of the fifth switch, turning on the fourth switch, and turning off the sixth switch; Turning on the second switch tube to charge the first inductor; The second switch tube is turned off to discharge the first inductor.

16. The charging system according to claim 14 or 15, characterized in that: The MCU is also used for: When the battery voltage is within the operating voltage range of the DC load, the first end and the second end of the fifth switch are turned on, and the sixth switch is turned on.

17. An electric vehicle, characterized in that: The invention comprises a power battery and a charging system as claimed in any one of claims 1 to 16, wherein the charging system is used for charging the power battery.

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