Control system for downhill operation and aerial platform

Abstract

The application relates to the technical field of engineering machinery, and discloses a control system for downhill working conditions and an aerial work platform. The control system comprises an energy consumer, a first switch device, an energy accumulator, a second switch device, and a control device. When powered on, the control device controls the second switch device to turn on the circuit of the energy accumulator to pre-charge the energy accumulator. When the voltage of the DC bus is equal to or greater than a first preset voltage, the control device controls the first switch device to turn on the circuit of the energy consumer to capture feedback current. When the voltage is less than or equal to a second preset voltage, the control device controls the second switch device to turn on the circuit of the energy accumulator to supply power to the driver. The application intervenes in the control strategy, pre-charges the energy accumulator when powered on, captures feedback current when there is a risk of stalling to reduce the feedback voltage of the driver, and supplies power to the driver by the pre-charged energy when the vehicle speed is reduced, so that the braking torque can be prevented from becoming small, the occurrence of the downhill stalling risk can be effectively inhibited, and smooth parking can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engineering machinery, in particular to a control system for downhill working condition and an aerial work platform. BACKGROUND

[0002] The driving system of an electrically driven aerial work platform (self-propelled) usually has no service brake, and its driving deceleration and parking rely on energy feedback type regenerative braking technology, and parking relies on electromagnetic brake or hydraulic brake. Such braking mode has a risk: when downhill, if the regenerative braking voltage exceeds the protection voltage of the drive, the braking torque will be limited (i.e. the strength of regenerative braking will be weakened), thus the aerial work platform has the risk of stalling. At this time, if the aerial work platform is parked through the emergency stop switch, the parking brake will directly lock up, forcing the aerial work platform to slide. On the one hand, the high-speed lock-up is harmful to the brake, and on the other hand, the braking distance may be longer. Moreover, even after the speed of the aerial work platform is reduced, the DC bus voltage of the drive may be lower than the minimum working voltage of the drive, thus the parking brake directly locks up, which is harmful to the parking brake to a great extent. SUMMARY

[0003] The purpose of the present application is to provide a control system for downhill working condition and an aerial work platform, which can intervene in the control strategy when the DC bus voltage exceeds a first preset voltage (e.g. a certain voltage lower than the protection voltage of the drive) (i.e. before the downhill overspeed occurs), and reduce the DC bus voltage of the drive by capturing the feedback current, thus avoiding the decrease of the braking torque, effectively inhibiting the occurrence of the downhill stalling risk, and supplying power to the drive by the pre-charged electric energy when the DC bus voltage is lower than a second preset voltage (e.g. a certain voltage higher than the minimum working voltage of the drive), to achieve smooth parking.

[0004] In order to achieve the above-mentioned purpose, the first aspect of the present application provides a control system for downhill working condition, comprising: a voltage detection device for detecting the DC bus voltage of a drive; an energy consumer for capturing the feedback current delivered by the drive; a first switch device for conducting a first circuit in which the energy consumer is located; an energy storage device; a second switch device for conducting a second circuit in which the energy storage device is located; and a control device for performing the following operations: when powered on, conducting the second circuit by controlling the second switch device to pre-charge the energy storage device by the battery; in the case that the DC bus voltage is equal to or greater than a first preset voltage, conducting the first circuit by controlling the first switch device to capture the feedback current by the energy consumer; and in the case that the DC bus voltage is less than or equal to a second preset voltage, conducting the second circuit by controlling the second switch device to supply power to the drive by the energy storage device, wherein the first preset voltage is greater than the second preset voltage.

[0005] Preferably, the first preset voltage is less than a protection voltage of the driver.

[0006] Preferably, the second preset voltage is greater than a minimum working voltage of the driver.

[0007] Preferably, the first switch device is a first high-frequency switch.

[0008] Preferably, the control device is configured to turn on the first circuit by controlling the first switch device, including: turning on the first circuit by controlling a duty cycle of the first high-frequency switch to control a speed of capturing the feedback current by the energy consumer, and in the case that the second switch device is a second high-frequency switch, the control device is configured to turn on the second circuit by controlling the second switch device to pre-charge the energy storage by the battery, including: turning on the second circuit by controlling a duty cycle of the second high-frequency switch to control a speed of pre-charging the energy storage by the battery.

[0009] Preferably, in the case that the second switch device includes a first contactor, a resistor and a second contactor, the second circuit includes: a first sub-circuit in which the first contactor and the resistor are connected in series; and a second sub-circuit in which the second contactor is located, wherein the first contactor and the resistor are both connected in parallel with the second contactor, accordingly, the control device is configured to turn on the second circuit by controlling the second switch device to pre-charge the energy storage by the battery, including: turning on the first sub-circuit by controlling the first contactor to be closed and the second contactor to be disconnected to pre-charge the energy storage by the battery, and the control device is configured to turn on the second circuit by controlling the second switch device to supply power to the driver by the energy storage, including: turning on the second sub-circuit by controlling the first contactor to be disconnected and the second contactor to be closed to supply power to the driver by the energy storage.

[0010] Preferably, the energy storage is a capacitor or a battery.

[0011] Preferably, the energy consumer is a resistor.

[0012] By the technical scheme, the application firstly turns on the circuit where the energy storage device is located to pre-charge the energy storage device at power-on, then turns on the circuit where the energy consumer is located to capture the feedback current by the energy consumer when the DC bus voltage is equal to or greater than the first preset voltage, and then turns on the circuit where the energy storage device is located to supply power to the driver by the energy storage device when the DC bus voltage is less than or equal to the second preset voltage. Thus, the application can intervene in the control strategy when the DC bus voltage exceeds the first preset voltage (for example, a voltage less than the protection voltage of the driver) (i.e., before the downhill overspeed occurs), and reduce the DC bus voltage of the driver by capturing the feedback current, thereby avoiding the decrease of the braking torque, effectively inhibiting the occurrence of the downhill stall risk, and supplying power to the driver by the pre-charged electric energy when the DC bus voltage is lower than the second preset voltage (for example, a voltage greater than the minimum working voltage of the driver), to realize smooth parking.

[0013] The second aspect of the application provides a high-altitude operation vehicle, which comprises the control system for the downhill working condition.

[0014] Preferably, the high-altitude operation vehicle further comprises a parking brake and a driver configured to control the parking brake to brake when the rotating speed of the motor is less than a preset rotating speed.

[0015] Other features and advantages of the application will be described in detail in the following specific embodiment part. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings are included to provide a further understanding of the application, and constitute a part of the specification, and are used together with the following specific embodiments to explain the application, but do not constitute a limitation on the application. In the drawings:

[0017] Figure 1 is a schematic diagram of a driving system comprising a control system according to an embodiment of the application;

[0018] Figure 2 is a schematic diagram of a control system for a downhill working condition according to an embodiment of the application;

[0019] Figure 3 is a schematic diagram of a control system for a downhill working condition according to an embodiment of the application; and

[0020] Figure 4 is a schematic diagram of a control system for a downhill working condition according to an embodiment of the application. DETAILED DESCRIPTION

[0021] The specific embodiments of the present application are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and explanatory and are not intended to limit the present application.

[0022] Before introducing the specific embodiments of the present application, two concepts are briefly described.

[0023] Regenerative braking: when the electric vehicle brakes, the (walking) motor can be controlled to operate as a generator, thereby converting the kinetic energy or potential energy of the vehicle into electrical energy and storing it in the energy storage module.

[0024] Feedback current: during regenerative braking, the driver converts the electrical energy generated by the (walking) motor into a current that can be used by the energy storage module or other energy-consuming elements. This current is called feedback current.

[0025] Figure 2 is a schematic diagram of a control system (i.e. safety protection device) provided by an embodiment of the present application for downhill working conditions. As shown in Figure 2 , the control system can include: a voltage detection device 10 for detecting the DC bus voltage of the driver; an energy consumer 20 for capturing the feedback current delivered by the driver; a first switching device 30 for conducting the first circuit in which the energy consumer 20 is located; an energy storage device 22; a second switching device 50 for conducting the second circuit in which the energy storage device is located; and a control device 40.

[0026] When the aerial work platform is descending, the motor operates in the generator state to maintain the vehicle speed unchanged, at which time the driver will generate a relatively high feedback electromotive force. Under normal circumstances, the driver will charge the battery, and the feedback electromotive force will not exceed the driver protection voltage.

[0027] The inventor found that during the operation of the aerial work platform, if the battery cannot be charged (the battery is fully charged, the battery power map is limited, the line is faulty, the battery management system (BMS) is faulty, etc.), the feedback electromotive force will quickly reach the driver protection voltage. In order to avoid the power electronic device being destroyed by high voltage, the driver reduces the feedback braking strength, resulting in insufficient braking torque, and the vehicle speed may become faster and faster, and the equipment has the risk of losing control. If the operator reduces the speed at this time by the speed control handle, since the feedback braking strength of the driver is limited and cannot achieve the effect of reducing the speed, the driver will control the parking brake to directly brake the brake after a certain period of time (usually 5S). If the operator stops the vehicle at this time by the emergency stop switch, the parking brake will directly brake the brake, forcing the equipment to slide. Both cases force the parking brake to brake at high speed. This high-speed brake mode, on the one hand, causes great damage to the brake, resulting in the risk that the aerial work platform cannot be parked on the slope; on the other hand, sliding results in a longer braking distance and poor lateral stability, and the aerial work platform has the risk of collision and side slip.

[0028] For example, if the battery system cannot supply power to the driver 2 and the motor 100 and cannot be charged when going downhill, Figure 1 As shown, the vehicle control unit (VCU) 90 and battery management system (BMS), powered by battery 110, continue to operate normally. After receiving status information from the BMS and performing a fault diagnosis, the VCU 90 issues a stop command and a warning message, thereby controlling the relay K1 that enables driver 2 to remain closed. As a result, the motor 100 enters the regenerative braking state from the motoring state. The energy generated by regenerative braking can maintain the normal operation of driver 2 and is far greater than the energy required for normal operation. Because the battery cannot be charged, the DC bus voltage of driver 2 rises rapidly (i.e., the vehicle stalls when going downhill).

[0029] Therefore, during the operation of the aerial work vehicle, whether the battery is fully charged, the battery power map is limited, or there is a battery failure, etc., it may cause the DC bus voltage of the driver to increase, causing the vehicle to stall when going downhill.

[0030] like Figure 3 As shown, the first switching device 30 may be a first high-frequency switch 31. Specifically, the first high-frequency switch 31 may be a field effect transistor (ie, a MoS transistor).

[0031] Wherein, the voltage detection device 10 can be a voltmeter 11, such as Figure 3 shown.

[0032] The control device 40 is a central processing unit (CPU) 41, such as Figure 3 shown.

[0033] The control device 40 is configured to perform the following operations: upon power-on, controlling the second switching device 50 to conduct the second circuit so that the battery pre-charges the energy storage device; when the DC bus voltage is equal to or greater than a first preset voltage, controlling the first switching device 30 to conduct the first circuit so that the energy consumer 20 captures the feedback current; and when the DC bus voltage is less than or equal to a second preset voltage, controlling the second switching device to conduct the second circuit so that the energy storage device supplies power to the driver.

[0034] The first preset voltage is greater than the second preset voltage. Specifically, the first preset voltage is less than the protection voltage of the driver 2. If the protection voltage of the driver is 100V, the first preset voltage can be set to be less than 100V (for example, the first preset voltage is 95V).

[0035] The second preset voltage is greater than the minimum operating voltage of the driver 2. In actual applications, the second preset voltage can be reasonably set according to specific conditions, which can be slightly greater than the minimum operating voltage (i.e. the lowest voltage when the driver is normally operating).

[0036] The control device is configured to control the first switch device to turn on the first circuit, including controlling the duty cycle of the first high-frequency switch to turn on the first circuit, so as to control the speed of capturing the feedback current by the energy consumer.

[0037] In an embodiment, the energy consumer 20 can be a resistor 25 (as shown in Figure 4 The energy storage device can be a capacitor or a battery.

[0038] Specifically, taking the resistor 25 (as shown in Figure 3 When the DC bus voltage displayed by the voltmeter 11 is equal to or greater than the first preset voltage (for example, 95V), that is, there is a risk of stalling, the CPU 41 controls the duty cycle of the first high-frequency switch 31 to turn on the circuit where the resistor 25 is located, so as to control the speed of consuming the feedback braking energy by the resistor 25, thereby controlling the feedback energy absorbed by the resistor, and further stabilizing the DC bus voltage (i.e. the feedback voltage) to prevent it from exceeding the protection voltage. At this time, since the driver does not limit the strength of the feedback braking, the speed of the aerial work vehicle becomes slower and slower, thereby avoiding the risk of stalling.

[0039] When the electric vehicle is downhill, the gravitational potential energy change of the downhill is usually absorbed by the mechanical brake, but the aerial work vehicle does not have a mechanical brake and can only rely on the battery charging to absorb. The absorption mode of the energy consumer designed in the present scheme solves the problem that the battery system cannot be absorbed due to failure or the like. By stabilizing the DC bus voltage, the problem that the driver loses power supply due to battery system failure or the like is solved, and the problem that the drive overvoltage alarm is caused by the high feedback braking electromotive force is prevented.

[0040] That is, in the present embodiment, if there is no energy storage device (such as an energy storage capacitor), when the DC bus voltage displayed by the voltmeter 11 is equal to or greater than the first preset voltage (i.e. there is a risk of stalling), the feedback braking energy is consumed by the energy consumption resistor, so as to control the DC bus voltage (i.e. the feedback voltage) of the driver to be lower than the protection voltage of the driver. At this time, since the driver does not limit the strength of the feedback braking, the speed of the aerial work vehicle can be controlled to be slower and slower. However, after the DC bus voltage is reduced (i.e. the speed is reduced), the DC bus voltage can be lower than the minimum operating voltage of the driver, thereby causing the parking brake to directly lock the brake, which has a certain degree of damage to the parking brake.

[0041] To overcome the above-mentioned defects, an energy storage device and corresponding circuit are added in the present embodiment to pre-charge the energy storage device at power-on. Thus, the energy storage device can be used to supply power to the drive after the DC bus voltage decreases (i.e. the vehicle speed decreases), thereby avoiding the direct brake of the parking brake controlled by the drive.

[0042] The energy storage device 22 can be a capacitor 24 or a battery, etc.

[0043] In the case that the second switch device is a second high-frequency switch, the control device is configured to control the second switch device to turn on the second circuit to pre-charge the energy storage device by the battery, which includes controlling the duty cycle of the second high-frequency switch to turn on the second circuit to control the speed of pre-charging the energy storage device by the battery.

[0044] In an embodiment, the second switch device 50 can be a second high-frequency switch 33 or a contactor (as shown in FIG. 3). Figure 3 Specifically, the second high-frequency switch 33 can be a field effect transistor (i.e. a MOS transistor).

[0045] Specifically, taking the energy storage device 22 as a capacitor 24 as an example, at power-on, the CPU 41 controls the duty cycle of the second high-frequency switch 33 to turn on the circuit where the second high-frequency switch 33 is located, so as to pre-charge the capacitor 22 by the battery. Then, when the DC bus voltage displayed by the voltmeter 11 is equal to or greater than the first preset voltage (i.e. there is a risk of stalling), the regenerative braking energy is consumed by the energy dissipation resistor, so that the DC bus voltage (i.e. the feedback voltage) of the drive can be controlled to be lower than the protection voltage of the drive. At this time, since the drive will not limit the strength of the regenerative braking, the vehicle speed of the aerial work vehicle can be controlled to be slower and slower. Therefore, when the DC bus voltage displayed by the voltmeter 11 is less than or equal to the second preset voltage (i.e. the feedback voltage is close to the minimum working voltage of the drive), the CPU 41 controls the second high-frequency switch 33 (which is equivalent to a contactor) to turn on the circuit where the second high-frequency switch 33 is located, so as to supply power to the drive 2 by the capacitor 24 (as shown in FIG. 3), thereby the capacitor 22 can provide auxiliary power for the drive 2 to complete the braking process (especially when the power system loses power). Figure 3 If the energy absorbed by the capacitor is insufficient, after the voltage decreases (i.e. the vehicle speed decreases), the drive may cause a serious undervoltage alarm, and the parking brake may be directly braked.

[0046] That is, the CPU 41 controls the duty cycle of the second high-frequency switch 33 to complete the pre-charging of the energy storage capacitor 24 at power-up. The pre-charging provides standby energy for the driver 2 to complete the deceleration process. When there is a risk of stall, the feedback braking energy is still absorbed by the energy dissipation resistor 25 to stabilize the DC bus voltage. After the voltage is reduced, the CPU controls the high-frequency switch to control the energy storage capacitor 24 to supply power to the driver, so that the corresponding vehicle speed can be smoothly reduced. When the motor 100 speed is lower than a certain value (such as 30 rpm), the parking brake is engaged.

[0047] In the case where the second switch device can include the first contactor 34, the resistor 60 and the second contactor 35, the second circuit can include: a first sub-circuit in which the first contactor 34 and the resistor 60 are connected in series; and a second sub-circuit in which the second contactor 35 is located. Wherein the first contactor 34 and the resistor 60 are connected in parallel with the second contactor 35.

[0048] Correspondingly, the control device 40 (for example, the CPU 41) for turning on the second circuit by controlling the second switch device to pre-charge the energy storage device by the battery includes: turning on the first sub-circuit by controlling the first contactor 34 to close and the second contactor 35 to open to pre-charge the energy storage device by the battery, and the control device 40 (for example, the CPU 41) for turning on the second circuit by controlling the second switch device to supply power to the driver by the energy storage device includes: turning on the second sub-circuit by controlling the first contactor 34 to open and the second contactor 35 to close to supply power to the driver by the energy storage device.

[0049] Specifically, in the case of power-up, the circuit in which the contactor 34 is closed and the contactor 35 is opened is turned on to pre-charge the capacitor 24 by the battery. Then, when the DC bus voltage displayed by the voltmeter 11 is equal to or greater than the first preset voltage (i.e., there is a risk of stall), the feedback braking energy is consumed by the energy dissipation resistor, so that the DC bus voltage (i.e., the feedback voltage) of the driver can be controlled to be lower than the protection voltage of the driver. At this time, since the driver will not limit the strength of the feedback braking, the speed of the aerial work vehicle can be controlled to be slower and slower. Therefore, in the case where the DC bus voltage displayed by the voltmeter 11 is less than or equal to the second preset voltage (i.e., the feedback voltage is close to the minimum working voltage of the driver), the CPU 41 turns on the circuit in which the contactor 34 is opened and the contactor 35 is closed to supply power to the driver 2 by the capacitor 24, as shown in FIG. 6. Figure 4The capacitor 24 can provide auxiliary power for the driver 2 to complete the braking process (especially when the power system loses power). Thus, the pre-charge function provides backup energy for the driver 2 to complete the deceleration process.

[0050] Compared with the embodiment shown in Figure 3 Compared with the embodiment shown in Figure 4 The embodiment shown in the figure uses a pre-charge circuit composed of a contactor 34 and a resistor 60 to pre-charge the capacitor 24, and uses a contactor 35 to turn on another circuit where the capacitor 24 is located to supply power to the driver using the capacitor 24. Since the pre-charge circuit and the power supply circuit are separated, the embodiment can achieve more reliable power supply purposes; and since the embodiment uses a simpler switching device (i.e., a contactor), it can achieve control purposes in a simpler way.

[0051] In an embodiment, the control system further comprises a digital-to-analog converter 70 for converting the analog signal of the DC bus voltage detected by the voltage detection device 10 into a digital signal, and outputting the converted digital signal of the DC bus voltage to the control device 40, as shown in the figure. Figure 3

[0052] The above-mentioned various embodiments can achieve downhill control of the vehicle based on the overspeed control mode of the DC bus voltage. The above-mentioned control mode has a stall protection function, which does not need to detect the speed of the vehicle and does not participate in speed control, but ensures that the driver can maximize the braking capacity of the motor by stabilizing the DC bus voltage, thereby preventing the vehicle from overspeeding. Since the vehicle will not overspeed, it is even less likely to stall. Therefore, during the operation of the aerial work platform, whether the battery is fully charged, the battery power map is limited, or the battery fails, etc. cause the DC bus voltage of the driver to be higher (or downhill stall), the overspeed control based on the DC bus voltage is inhibited from the source, thereby effectively preventing the generation of downhill stall risk.

[0053] ​In summary, the application is creative in that firstly, at power-on, the circuit in which the energy storage device is located is turned on to pre-charge the energy storage device, then in the case that the DC bus voltage is equal to or greater than a first preset voltage, the circuit in which the energy consumer is located is turned on to capture the feedback current by the energy consumer, and then in the case that the DC bus voltage is less than or equal to a second preset voltage, the circuit in which the energy storage device is located is turned on to supply power to the driver by the energy storage device. Thus, the application can intervene in the control strategy when the DC bus voltage exceeds the first preset voltage (for example, a voltage less than the protection voltage of the driver), that is, before the downhill overspeed occurs, and reduce the DC bus voltage of the driver by capturing the feedback current, thereby avoiding the decrease of the braking torque, effectively inhibiting the occurrence of the downhill stall risk, and supplying power to the driver by the pre-charged electric energy when the DC bus voltage is lower than the second preset voltage (for example, a voltage greater than the minimum working voltage of the driver), to achieve smooth parking.

[0054] An embodiment of the application further provides a high-altitude operation vehicle, which can comprise the control system for downhill working conditions (i.e., the safety protection device).

[0055] The high-altitude operation vehicle can further comprise a parking brake 120 and a driver 2 configured to control the parking brake 120 to brake when the rotating speed of the motor is less than a preset rotating speed.

[0056] In an embodiment, the high-altitude operation vehicle can further comprise a battery 80, a vehicle control unit (VCU) 90, a motor 100, a speed reducer 130, a wheel 140, and a DC / DC converter 150, as shown in Figure 2 The battery 80 is configured with a battery management system (BMS), and the VCU 90 exchanges information with the BMS through a CAN bus. The VCU 90 can adjust the target rotating speed of the motor 100 according to the battery state and fault information sent by the BMS.

[0057] Specifically, the feedback current generated by the regenerative braking is captured by the control system for downhill working conditions, and since the driver 2 does not limit the intensity of the feedback braking, the motor 100 can realize the speed reduction control of the wheel 140 through the speed reducer 130, so that the vehicle speed becomes lower and lower. In addition, when the rotating speed of the motor 100 is less than a preset rotating speed, the parking brake is controlled to brake to realize smooth parking. Therefore, when the driving system fails, the embodiment can adopt the mode of first speed reduction and then brake holding, so as to reduce the damage to the parking brake as much as possible, thereby prolonging the service life of the parking brake.

[0058] The above embodiment can absorb the energy generated by the resistive feedback braking and control the vehicle speed to reduce in time. When the feedback energy is insufficient, the energy pre-charged by the energy storage capacitor can supply power in time to maintain the normal operation of the driver until the vehicle is completely stopped. Thus, the parking brake can be guaranteed not to be damaged by dynamic impact energy, the probability of high-speed brake holding can be greatly reduced, the service life of the parking brake can be prolonged, the risk of hill parking and slope sliding can be reduced, and thus a safer and more reliable downhill can be realized.

[0059] The specific details and benefits of the aerial work platform provided by the embodiment of the present application can be referred to the description of the feedback current control device above, and will not be described here.

[0060] The preferred embodiments of the present application are described in detail above with reference to the accompanying drawings, but the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, and these simple modifications all belong to the protection scope of the present application.

[0061] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, various possible combinations are not described again by the present application.

[0062] In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not deviate from the idea of the present application, and it should also be considered as disclosed by the present application.

Claims

1. A control system for downhill conditions, characterized in that: The control system includes: a voltage detection device for detecting a DC bus voltage of a driver used for battery charging; an energy consumer for capturing feedback current delivered by the driver; a first switching device, configured to conduct a first circuit in which the energy consumer is located; Energy storage device; a second switching device, configured to conduct a second circuit in which the energy storage device is located; and Controls for: When powered on, controlling the second switch device to conduct the second circuit so as to pre-charge the energy storage device with the battery; When the DC bus voltage is equal to or greater than a first preset voltage, controlling the first switching device to conduct the first circuit so that the energy consumer captures the feedback current; and When the DC bus voltage is less than or equal to a second preset voltage, the second circuit is turned on by controlling the second switching device so that the energy storage device supplies power to the driver. Wherein, the first preset voltage is greater than the second preset voltage, The first switching device is a first high-frequency switch; The control device is configured to conduct the first circuit by controlling the first switch device, comprising: conducting the first circuit by controlling a duty cycle of the first high-frequency switch to control a speed at which the energy consumer captures the feedback current, and In the case where the second switching device is a second high-frequency switch, the control device is configured to control the second switching device to conduct the second circuit so that the battery pre-charges the energy storage device, including: conducting the second circuit by controlling a duty cycle of the second high-frequency switch so as to control a speed at which the battery pre-charges the energy storage device; In the case where the second switching device includes a first contactor, a resistor, and a second contactor, the second circuit includes: a first subcircuit in which the first contactor and the resistor are connected in series; and a second subcircuit in which the second contactor is located, wherein both the first contactor and the resistor are connected in parallel with the second contactor. Accordingly, the control device is configured to control the second switching device to conduct the second circuit so that the battery pre-charges the energy storage device, including: controlling the first contactor to close and the second contactor to open to conduct the first sub-circuit so that the battery pre-charges the energy storage device.

2. The control system according to claim 1, characterized in that: The first preset voltage is lower than a protection voltage of the driver.

3. The control system according to claim 1, characterized in that: The second preset voltage is greater than the minimum operating voltage of the driver.

4. The control system according to claim 1, characterized in that: The control device is used to control the second switching device to conduct the second circuit so that the energy storage can power the driver, including: controlling the first contactor to open and the second contactor to close to conduct the second sub-circuit so that the energy storage can power the driver.

5. The control system according to claim 1, characterized in that: The energy storage device is a capacitor or a battery.

6. The control system according to claim 1, characterized in that: The energy dissipator is a resistor.

7. An aerial work vehicle, characterized in that: The aerial work vehicle comprises: a control system for downhill working conditions according to any one of claims 1 to 6.

8. The aerial work vehicle according to claim 7, characterized in that: The aerial work vehicle also includes: parking brake; and The driver is used to control the parking brake to brake when the rotation speed of the motor is less than a preset rotation speed.

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