A high-voltage system of an electric vehicle, a high-voltage control method and an electric vehicle

Abstract

The application discloses a high-voltage system and a high-voltage control method of an electric vehicle, and the electric vehicle, which comprises a current collection circuit, is used for collecting residual electric energy of high-voltage load components in a high-voltage load circuit when the electric vehicle is powered off under high voltage; and the stored electric energy is charged into the high-voltage load circuit when the electric vehicle is powered on under high voltage, wherein the current collection circuit is connected at both ends of the high-voltage load circuit. The application collects energy when the electric vehicle is powered off under high voltage and converts the energy into pre-charging energy when the electric vehicle is powered on, so that the electric vehicle is more suitable for the development trend of the voltage platform rising.

Description

Technical Field

[0001] This invention belongs to the field of high-voltage control technology for electric vehicles, specifically relating to the control of power-on and power-off of a high-voltage system for electric vehicles. Background Technology

[0002] The electrification of automobiles is an important component of the energy conservation and emission reduction development strategy and the green economy. In recent years, the sales of new energy vehicles have increased rapidly, with pure electric vehicles accounting for over 80% of new energy vehicle sales. Electric vehicle technology is booming, and the 800V high-voltage system is hailed as a new starting point for electric vehicle technology, becoming a focus of attention for major automakers. Compared to the current 400V architecture, the 800V high-voltage system increases the voltage of the high-voltage power network, significantly reducing the current during charging and discharging at the same power. Similarly, during high-voltage discharge, the smaller current results in less heat loss, improving system discharge efficiency and thus extending driving range. Because of the advantages of high-voltage systems in charging time and driving range, addressing the most critical pain points for customers, they have become a hot topic in the industry.

[0003] However, 800V technology also faces some challenges. The industry consensus is that silicon carbide (SiC)-based semiconductors are replacing silicon-based semiconductors. Silicon-based semiconductors are widely used in electromagnetic switches and unidirectional conduction components in 400V electric vehicle systems, but their voltage withstand capability cannot meet the requirements of the 800V high-voltage platform. While SiC-based semiconductors offer higher voltage withstand levels, their manufacturing process is still maturing and their cost is relatively high. 800V systems also result in longer high-voltage unloading and pre-charging times, requiring related high-voltage systems and control schemes to be matched and optimized for 800V.

[0004] When the driver requests a high-voltage power-off via key, button, or remote operation; or when maintenance personnel activate the high-voltage maintenance switch for emergency power-off; or in the event of a sudden vehicle malfunction or collision, the vehicle's high-voltage system must quickly disconnect the battery pack's power supply to ensure the safety of the high-voltage load network. National standards also impose strict requirements on the voltage and residual charge after a high-voltage power-off. To disconnect the high-voltage network's energy supply, the battery pack's main positive and negative switches will open. As the main positive and negative switches close, equipment in the load circuit, such as the inverter-motor system, air conditioning compressor, and DC-DC converter, will have residual voltage. To quickly unload this residual voltage, a common approach is for the inverter-motor system to statically operate and consume this excess energy after the battery pack's positive and negative terminals are disconnected, thus achieving the goal of quickly unloading the voltage.

[0005] The current high-voltage unloading scheme has the advantages of no additional components, no hardware cost, and easy implementation. However, it also has common disadvantages: (1) During motor rotation, the stator and rotor of the motor move relative to each other, which is not conducive to rapid voltage unloading. Because most electric vehicles have motors and wheels that are constantly connected, the motor will rotate as long as the wheels rotate. Therefore, when the vehicle is powered off at a certain speed, there is a delay in unloading the high voltage using the inverter-motor itself; (2) If the compressor air conditioner is running at a high speed, after the vehicle is powered off, it will also generate an electromotive force due to the compressor running idle, which also causes the high-voltage unloading speed to be slow; (3) Relying on the static operation of the motor actually converts the residual electrical energy into heat and dissipates it, failing to utilize this energy and resulting in waste.

[0006] Generally, the power-on process of an electric vehicle's high-voltage system includes a pre-charging phase. Before the main positive switch of the battery pack is closed, the high-voltage pre-charging circuit is first connected to pre-load voltage onto the high-voltage electrical equipment. Pre-charging allows for early checks of the high-voltage circuit for potential problems. If the pre-charging fails to reach the predetermined voltage, issues such as short circuits or insulation abnormalities may exist. Pre-charging also prevents damage to electrical components caused by a sudden voltage load when the main positive switch is closed. Common damages from sudden voltage loads include switch overload, circuit burning, and capacitor breakdown, thus ensuring the safe and reliable operation of the vehicle and its components. Once the predetermined voltage is reached, the pre-charging circuit is disconnected, pre-charging ends, the main positive switch closes, and the vehicle's high-voltage load equipment can then obtain battery power through the high-voltage network to operate. For example, the inverter-motor system can convert DC to AC for driving, the DC-DC converter can perform step-down conversion, and the air conditioning system can provide heating or cooling. Summary of the Invention

[0007] In order to accelerate the unloading of high voltage, ensure the safety of the vehicle power grid, and make full use of electrical energy, this invention proposes a high voltage system, control method, and electric vehicle for electric vehicles.

[0008] One of the objectives of this invention is an electric vehicle high-voltage system, which includes a collector circuit. The collector circuit is used to collect the residual electrical energy of the high-voltage load components in the high-voltage load circuit during high-voltage power-on operation and to charge the stored electrical energy into the high-voltage load circuit during pre-charging operation before high-voltage power-on. The collector circuit is connected to both ends of the high-voltage load circuit.

[0009] The current collector circuit includes an energy storage circuit, a control circuit, a step-down circuit, and a unidirectional conduction circuit;

[0010] The energy storage circuit is used to store the residual electrical energy collected by the high-voltage load circuit under high-voltage electrical conditions; it is also used to charge the stored electrical energy into the high-voltage load circuit under pre-charging conditions before high-voltage power-on.

[0011] The control circuit controls the charging and discharging state of the collector circuit. When the high voltage is applied, it controls the energy storage circuit to charge in parallel. When the high voltage is applied and the circuit is pre-charged, it controls the energy storage circuit to discharge.

[0012] The step-down circuit is connected between the battery pack of the electric vehicle and the high-voltage load circuit, and is connected in series with the energy storage circuit to step down the voltage of the energy storage circuit under high-voltage electrical conditions.

[0013] The unidirectional conduction circuit is connected in parallel with the step-down circuit to conduct current in one direction.

[0014] The energy storage circuit includes multiple capacitors. Under high-voltage power-on conditions, the multiple capacitors are connected in parallel to receive the residual power of the high-voltage load components in the high-voltage load circuit for energy storage. Under the pre-charging condition before high-voltage power-on, the multiple capacitors are connected in parallel to pre-charge the high-voltage load components in the high-voltage load circuit, or the multiple capacitors are connected in series to pre-charge the high-voltage load in the high-voltage load circuit.

[0015] The energy storage circuit includes at least two capacitors. The positive terminal of the first capacitor is connected to one end of the step-down circuit, and the negative terminal of the first capacitor is connected to a fourth diode. The fourth diode is connected to a third resistor. A second diode is connected in series between the positive terminal of the second capacitor and the positive terminal of the first capacitor. A third diode and a second switch are connected in series between the positive terminal of the second capacitor and the fourth diode. The second switch closes when the second capacitor discharges.

[0016] Furthermore, the positive terminal of the second capacitor is connected to the second resistor.

[0017] The collector circuit also includes a fuse F1 located between the step-down circuit and the energy storage circuit, which is used to prevent the collector circuit current from being too large, which would cause the first capacitor C1 and the second capacitor C2 to break down and form charging and discharging overcurrent.

[0018] A second objective of this invention is a high-voltage control method for electric vehicles, wherein, under high-voltage power-off conditions, a collector circuit collects the residual electrical energy of the high-voltage load components in the high-voltage load circuit; and under pre-charging conditions before high-voltage power-on, the stored electrical energy is charged into the high-voltage load circuit, wherein the collector circuit is connected to both ends of the high-voltage load circuit.

[0019] An electric vehicle that achieves the third objective of the present invention includes a high-voltage control system comprising a collector circuit. The collector circuit is used to collect residual electrical energy from high-voltage load components in the high-voltage load circuit during high-voltage power-on operation and to charge the stored electrical energy into the high-voltage load circuit during pre-charging operation before high-voltage power-on. The collector circuit is connected to both ends of the high-voltage load circuit.

[0020] Beneficial effects:

[0021] 1. During high-voltage unloading, collect and store as much electrical energy as possible during the unloading voltage, and convert it into pre-charge energy when the vehicle is powered on. This can accelerate the unloading voltage, ensure the safety of the vehicle's power grid, recover and utilize energy, and also provide storage overload protection.

[0022] 2. During high-voltage pre-charging, release as much collected electrical energy as possible, and ensure that the voltage does not overload during release;

[0023] 3. The timing of unloading storage and pre-charge release is controllable, and its steps can be coordinated with the original electric vehicle circuit's unloading and pre-charge circuits. Specifically: during high-voltage unloading, the collector capacitor circuit only collects the residual electrical energy of the load network after the main positive and main negative relays of the battery pack are disconnected, preventing the battery pack from charging the collector capacitor circuit; during high-voltage pre-charge, the capacitor releases its charge to boost the circuit voltage before the pre-charge circuit closes, preventing the pre-charge circuit from charging the collector capacitor circuit.

[0024] 4. It can reduce the use of electrical components such as switches and diodes on silicon carbide substrates, thus reducing costs. Attached Figure Description

[0025] Figure 1 This is the high-voltage system structure described in this invention;

[0026] Figure 2 This is a flowchart illustrating the high-voltage power-on pre-charging process according to an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the high-voltage electrical operating condition according to an embodiment of the present invention. Detailed Implementation

[0028] The following detailed embodiments are provided to explain the technical solutions of the claims of this invention, so that those skilled in the art can understand the claims. The scope of protection of this invention is not limited to the following specific embodiments. Any modifications made by those skilled in the art that incorporate the technical solutions of the claims but differ from the following detailed embodiments are also within the scope of protection of this invention.

[0029] Design scheme as follows Figure 1 As shown, in a typical high-voltage circuit, adding something like... Figure 1 The collector circuit shown in the dashed box.

[0030] The current collector circuit is connected to both ends of the high-voltage load circuit and is used to collect the residual electrical energy of the high-voltage load components in the high-voltage load circuit during high-voltage power-on operation. During the pre-charging operation before high-voltage power-on, the stored electrical energy is charged into the high-voltage load circuit. The current collector circuit is connected to both ends of the high-voltage load circuit. The high-voltage load circuit is a high-voltage circuit that connects high-voltage load components such as DC-DC converters, heaters, compressors, and motor-inverter systems. Its connection to the positive and negative terminals of the battery power supply circuit is controlled to be turned on and off by the main positive and main negative relays, respectively.

[0031] The collector circuit includes a step-down circuit, one end of which is connected to the high-voltage load circuit and the other end is connected to the energy storage circuit. It is used to step down the voltage of the energy storage circuit under high-voltage electrical conditions. In this embodiment, it includes a first resistor R1. The first resistor R1 is used to share part of the high voltage unloading under high-voltage electrical conditions to reduce the charging voltage of capacitors C1 and C2.

[0032] The collector circuit includes a unidirectional conduction circuit, which is connected in parallel with the step-down circuit to conduct current unidirectionally; in this embodiment, it includes a first diode D1, which is connected in parallel with a first resistor R1; under high voltage power-down conditions, the current output from the high voltage load circuit charges the capacitor only through the first resistor R1; under the pre-charging condition before high voltage power-on, the current is output to the high voltage load circuit only through the first diode D1.

[0033] The collector circuit also includes an energy storage circuit, which is used to store the residual power collected by the high-voltage load circuit under high-voltage power conditions; and to charge the stored power into the high-voltage load circuit under pre-charging conditions before high-voltage power-on.

[0034] The energy storage circuit includes multiple capacitors. Under high-voltage power conditions, the multiple capacitors are connected in parallel to receive residual power from the high-voltage load components in the high-voltage load circuit for energy storage. Under pre-charging conditions before high-voltage power-on, the multiple capacitors are connected in parallel to pre-charge the high-voltage load components in the high-voltage load circuit, or the multiple capacitors are connected in series to pre-charge the high-voltage load in the high-voltage load circuit. In this embodiment, the energy storage circuit includes a first capacitor C1 and a second capacitor C2. The positive terminal of the first capacitor C1 is directly connected to one end of the step-down circuit or connected to one end of the step-down circuit through fuse F1. The negative terminal of the first capacitor C1 is connected to one end of the fourth diode D4, and the other end of the fourth diode D4 is connected to the third resistor R3. The positive terminal of the second capacitor C2 is connected in series with the positive terminal of the first capacitor C1, and the positive terminal of the second capacitor C2 is connected in series with the third diode D3 and the second switch S2. The second switch S2 is closed when the second capacitor D2 discharges.

[0035] Under high-voltage pre-charging conditions, the second diode D2 and the fourth diode D4 control the current flowing from the second capacitor C2 through the third diode D3 and the second switch S2 in the control circuit to the first capacitor C1, thus connecting the first capacitor C1 and the second capacitor C2 in series. Under high-voltage de-energizing conditions, when the residual voltage is lower than the potential across the first capacitor C1 and the second capacitor C2, the second diode D2 and the fourth diode D4 are used to maintain the charge on the first capacitor C1 and the second capacitor C2, respectively. Under the pre-charging condition before high-voltage energizing, diodes D2~D4 control the first capacitor C1... Second capacitor Discharge is performed in series to increase the discharge voltage.

[0036] The positive terminal of the second capacitor C2 is also connected to the second resistor R2, which reduces the voltage surge to the second capacitor C2 when the high voltage is unloaded under high voltage operating conditions; and reduces the charging of the first capacitor C1 to the second capacitor C2 when there is a potential difference between the first capacitor C1 and the second capacitor C2 under high voltage pre-charging conditions.

[0037] The collector circuit includes a control circuit that controls the charging and discharging state of the collector circuit. When the high voltage is applied, the energy storage circuit is controlled to charge in parallel. When the high voltage is applied before pre-charging, the energy storage circuit is controlled to discharge. In this embodiment, when the high voltage is applied, the first switch S1 is closed and the second switch S2 is opened to collect residual electricity from the high voltage load circuit. When the high voltage is applied before pre-charging, the first switch S1 and the second switch S2 are closed simultaneously to charge the energy stored in the collector circuit into the high voltage load circuit.

[0038] Specifically, the collector circuit in this embodiment is as follows: Figure 1 As shown, it includes:

[0039] One end of the first switch S1 is connected to one end of the battery pack in the high-voltage load circuit, and the other end is connected to one end of the first resistor R1 and the cathode of the first diode D1. The anode of the first diode D1 is connected to the other end of the first resistor R1. The other end of the first resistor R1 is connected to one end of the first capacitor C1 and the anode of the second diode D2 through the fuse F1. The other end of the second diode D2 is connected to one end of the second resistor R2. The other end of the first capacitor C1 is connected to the anode of the fourth diode D4 and one end of the second switch S2. The other end of the second resistor R2 is connected to one end of the second capacitor C2 and the anode of the third diode D3. The other end of the second capacitor C2 is grounded. The cathode of the fourth diode D4 is connected to the negative terminal of the high-voltage load circuit through the resistor R3. The other end of the second switch S2 is connected to the cathode of the third diode D3.

[0040] During the pre-charging condition before high-voltage power-on, the switch S connected to the negative terminal of the battery pack in the high-voltage load circuit... 主负 Disconnecting and connecting the S terminal of the battery pack positive terminal主正 When both are disconnected, switch S1, which connects to the battery pack in the current collector circuit, is closed, and the residual high voltage in the high voltage load circuit charges the first capacitor C1 and the second capacitor C2 through the first resistor R1.

[0041] When the collector circuit is in charging state, the second switch S2 is open, at which time the capacitor... and In parallel charging mode, when the residual voltage of the high-voltage load circuit is higher than the potential across the capacitor in the collector circuit, the capacitor charges. When the residual voltage gradually decreases and falls below the potential across the capacitor, the capacitor charge is maintained due to the presence of diodes D2 and D4, and no energy is released. After the collection is completed, the first switch S1 is opened.

[0042] Due to the first resistor The first diode in parallel Due to its unidirectional flow characteristic, current does not flow through the first diode during charging of the collector circuit. And flowing through the first When current flows through a resistor, the potential decreases, thus causing the capacitor to... and The charging voltage should be appropriately reduced, and the resistance should be adjusted accordingly. and These are protective capacitors. and Traffic throttling. , and Resistors can reduce voltage surges during high-voltage unloading.

[0043] resistance By selecting the appropriate resistance value, the voltage difference across the diode can be kept within a reasonable range, thereby protecting the diode. It is not subject to reverse breakdown. The effect of this design is to reduce the withstand voltage rating of components containing semiconductor materials, such as switches and diodes, thereby reducing the overall component selection cost.

[0044] Considering the voltage divider effect of R1 during collector voltage collection, R1 accounts for 30%-40% of (R1+R2*R3 / (R2+R3)); considering the protection of diode D1 against breakdown voltage, the resistance value of R1 satisfies:

[0045] 800V*(R1 / (R1+R2*R3 / (R2+R3)))<2*V D1

[0046] Where: V D1 This is the breakdown voltage of diode D1.

[0047] The working principle of this collector circuit is as follows:

[0048] (a) Under high-voltage electrical operating conditions:

[0049] During normal high-voltage unloading, switch S 主负 Disconnect, then S 主正 Disconnect; S 预充 It closes only during power-on pre-charging and opens immediately after pre-charging is complete. It remains open when high-voltage load components are in operation.

[0050] Under high-voltage operating conditions after adding a collector circuit, switch S 主负 S 主正 S 预充 Consistent with the normal high-pressure unloading state;

[0051] like Figure 3 As shown, in the high-voltage collector circuit, when switch S1 is closed, the residual high voltage from the high-voltage load circuit connected to the high-voltage equipment voltage circuit charges the capacitor through resistor R1. When the collector circuit is charging, switch S2 is open. From the circuit principle, it can be seen that C1 and C2 are charging in parallel at this time. When the residual voltage of the high-voltage load circuit is higher than the potential across the capacitor in the collector circuit, the capacitor charges; as the residual voltage gradually decreases and falls below the potential across the capacitor, the capacitor retains its charge due to the presence of diodes D2 and D4, and does not release energy. After the collector circuit is completed, switch S1 opens.

[0052] The function of resistor R1 is to partially unload the high voltage. Because diode D1, connected in parallel with R1, has a unidirectional current flow, during charging of the collector circuit, the current flows through R1 instead of D1. The potential decreases after the current passes through the resistor, thus appropriately reducing the charging voltage of C1 and C2. R2 and R3 respectively limit the current of C1 and C2. Secondly, resistors R1 to R3 all reduce voltage surges during high-voltage unloading. Thirdly, the voltage difference across resistor R1 can be kept within a reasonable range by selecting its resistance value, thereby protecting diode D1 from reverse breakdown. This design allows for a lower voltage rating for components containing semiconductor materials, such as switches and diodes, thereby reducing the overall component selection cost.

[0053] F1 fuses are protective circuits that prevent excessive current in the collector circuit. For example, if the capacitor breaks down, it may cause charging or discharging overcurrent.

[0054] (ii) Pre-charge condition before high-voltage power-on:

[0055] Generally, when applying high pressure to a high-voltage system, the S1 switch is turned off first. 主负 Then turn off S 预充 Enter the high-voltage pre-charge procedure, wait for the voltage pre-charge to rise to the threshold, then disconnect S. 预充 End high-voltage pre-charge, then close S. 主正 The high-voltage system is ready for discharge.

[0056] The high-voltage loading process after adding a collector circuit differs from the high-voltage loading process of a typical high-voltage system, such as... Figure 2 As shown, first turn off S 主负 Then, turn off switches S1 and S2, entering the collector circuit discharge state. After a certain period of time (adjusted according to the capacitor discharge rate), turn on switches S1 and S2, completing the collector circuit discharge. Then, turn off switch S1 and S2. 预充 Enter the high-voltage pre-charge procedure, wait for the voltage pre-charge to rise to the threshold, then disconnect S. 预充 End high-voltage pre-charge, then close S. 主正 The high-voltage system is ready for discharge; the threshold for pre-charge voltage is generally 760V.

[0057] In the discharge state of the collector circuit, after S1 and S2 are closed, under the unidirectional current control of diodes D2, D3 and D4, and the combined effect of resistors R2 and R3 to prevent backflow, capacitors C1 and C2 discharge in parallel, thereby increasing the discharge voltage and quickly charging the electrical energy stored in the collector circuit into the high-voltage circuit of the load as much as possible.

[0058] The function of diode D1 is to short-circuit resistor R1 during the discharge process of the collector circuit. In this way, the current flows through diode D1 instead of resistor R1, reducing unnecessary power consumption.

[0059] The main components are pre-specified as follows: the resistance values ​​of resistors R1~R3 ​​are 2KΩ, 5KΩ, and 5KΩ respectively; the capacitance of capacitors C1 and C2 is 4μF, and the rated current of F1 is 20A.

[0060] This application embodiment also provides an electric vehicle. The high-voltage control system of the electric vehicle includes a collector circuit. The collector circuit is used to collect the residual electrical energy of the high-voltage load components in the high-voltage load circuit when the high-voltage power-on condition is under operation; and to charge the stored electrical energy into the high-voltage load circuit when the high-voltage power-on pre-charging condition is under operation. The collector circuit is connected to both ends of the high-voltage load circuit. In this embodiment, the high voltage is 800V.

[0061] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A high-voltage system for an electric vehicle, characterized in that, It includes a collector circuit, which is used to collect the residual electrical energy of the high-voltage load components in the high-voltage load circuit during high-voltage power-on operation; and to charge the stored electrical energy into the high-voltage load circuit during the pre-charging operation before high-voltage power-on. The collector circuit is connected to both ends of the high-voltage load circuit. The current collector circuit includes an energy storage circuit, a control circuit, a step-down circuit, and a unidirectional conduction circuit; The energy storage circuit is used to store the residual electrical energy collected by the high-voltage load circuit under high-voltage electrical conditions; it is also used to charge the stored electrical energy into the high-voltage load circuit under the pre-charging condition before high-voltage power-on. The control circuit controls the charging and discharging state of the collector circuit. When the high voltage is applied, it controls the energy storage circuit to charge in parallel. When the high voltage is applied and the circuit is pre-charged, it controls the energy storage circuit to discharge. The step-down circuit is connected between the battery pack and the high-voltage load circuit, and is connected in series with the energy storage circuit. It is used to step down the voltage of the energy storage circuit under high-voltage electrical conditions. A unidirectional conduction circuit is connected in parallel with a step-down circuit to enable unidirectional current conduction. The energy storage circuit includes multiple capacitors, at least two of which are capacitors. The positive terminal of the first capacitor is connected to one end of the step-down circuit, and the negative terminal of the first capacitor is connected to a fourth diode. The fourth diode is connected to a third resistor. A second diode is connected in series between the positive terminal of the second capacitor and the positive terminal of the first capacitor. A third diode and a second switch are connected in series between the positive terminal of the second capacitor and the fourth diode. The second switch closes when the second capacitor discharges.

2. The high-voltage system for an electric vehicle as described in claim 1, characterized in that, Under high-voltage electrical conditions, the multiple capacitors connected in parallel receive residual electrical charge from the high-voltage load components in the high-voltage load circuit for energy storage. Under the pre-charging condition before high-voltage power-on, the multiple capacitors connected in parallel pre-charge the high-voltage load components in the high-voltage load circuit, or the multiple capacitors connected in series pre-charge the high-voltage load in the high-voltage load circuit.

3. The high-voltage system for an electric vehicle as described in claim 1, characterized in that, The positive terminal of the second capacitor is connected to the second resistor.

4. A high-voltage control method for an electric vehicle according to the system described in claim 1, characterized in that, Under high voltage power-on conditions, the collector circuit collects the residual electrical energy of the high voltage load components in the high voltage load circuit; under the pre-charging condition before high voltage power-on, the stored electrical energy is charged into the high voltage load circuit, and the collector circuit is connected to both ends of the high voltage load circuit.

5. The electric vehicle high-voltage control method as described in claim 4, characterized in that, Under high-voltage electrical conditions, the control circuit in the current collector circuit controls the energy storage circuit in the current collector circuit to charge in parallel. The energy storage circuit stores the residual power collected by the high-voltage load circuit. The step-down circuit connected in series between the battery pack and the high-voltage load circuit and the energy storage circuit reduces the voltage of the energy storage circuit. Under the pre-charging condition before high-voltage power-on, the energy storage circuit charges the stored power into the high-voltage load circuit. The unidirectional conduction circuit connected in parallel with the step-down circuit conducts current unidirectionally.

6. The electric vehicle high-voltage control method as described in claim 5, characterized in that, The energy storage circuit includes multiple capacitors. Under high-voltage power-on conditions, the multiple capacitors are connected in parallel to receive the residual power of the high-voltage load components in the high-voltage load circuit for energy storage. Under the pre-charging condition before high-voltage power-on, the multiple capacitors are connected in parallel to pre-charge the high-voltage load components in the high-voltage load circuit, or the multiple capacitors are connected in series to pre-charge the high-voltage load in the high-voltage load circuit.

7. The electric vehicle high-voltage control method as described in claim 5, characterized in that, The energy storage circuit includes at least two capacitors. The positive terminal of the first capacitor is connected to one end of the step-down circuit, and the negative terminal of the first capacitor is connected to a fourth diode. The fourth diode is connected to a third resistor. A second diode is connected in series between the positive terminal of the second capacitor and the positive terminal of the first capacitor. A third diode and a second switch are connected in series between the positive terminal of the second capacitor and the fourth diode. The second switch closes when the second capacitor discharges.

8. An electric vehicle comprising the system of claim 1, characterized in that, The high-voltage control system of an electric vehicle includes a collector circuit, which is used to collect the residual electrical energy of the high-voltage load components in the high-voltage load circuit during high-voltage power-on operation and to charge the stored electrical energy into the high-voltage load circuit during pre-charging operation before high-voltage power-on. The collector circuit is connected to both ends of the high-voltage load circuit.

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