High pressure power system

Abstract

This invention provides a high-voltage power system, belonging to the field of electric vehicle technology. The system includes a high-voltage power circuit and a control device. The high-voltage power circuit is equipped with a first protection device and a second protection device. The control device is configured to: when the real-time current in the high-voltage power circuit is within a preset current protection range, control the current in the high-voltage power circuit to achieve a first expected result through the first protection device corresponding to the current protection range; and if the first expected result cannot be achieved within a first preset time period through the first protection device, or if the cumulative time the real-time current is within the current protection range reaches a second preset time period, then shut down the high-voltage power circuit through the second protection device corresponding to the current protection range. When the first protection device cannot effectively reduce the overcurrent risk in the high-voltage power circuit, timely shutdown of the high-voltage power circuit through the second protection device can reduce the safety risk of the high-voltage power circuit under overcurrent or short-circuit conditions.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle technology, and more specifically to a high-voltage power system. Background Technology

[0002] In the field of electric vehicle safety, the safety of high-voltage electrical systems is of paramount importance. Major safety accidents such as arcing, burning, and even smoke and fire caused by short circuits, overloads, and overcurrents in electrical systems frequently occur in the industry, causing huge losses to users and seriously hindering the development of the industry.

[0003] In the existing technology, electric vehicles use only relays and fuses for safety protection in high-voltage electrical circuits. However, relying solely on relays and fuses cannot prevent major safety accidents in all situations. Summary of the Invention

[0004] The purpose of this invention is to provide a high-voltage power system that can reduce the safety risks of high-voltage power circuits under overcurrent or short-circuit conditions.

[0005] To achieve the above objectives, embodiments of the present invention provide a high-voltage power system, including a high-voltage power circuit and a control device, wherein the high-voltage power circuit is provided with a first protection device and a second protection device.

[0006] The control device is configured as follows:

[0007] When the real-time current in the high-voltage power circuit is within a preset current protection range, the current in the high-voltage power circuit is controlled by the first protection device corresponding to the current protection range to achieve the first expected result; and

[0008] If the first expected result cannot be achieved within the first preset time period through the first protection device, or if the cumulative time during which the real-time current is within the current protection range reaches the second preset time period, then the high-voltage power circuit will be shut off through the second protection device corresponding to the current protection range.

[0009] Preferably, the first preset duration is less than the second preset duration.

[0010] Preferably, the current protection intervals are arranged in ascending order of the value at the left endpoint and / or the right endpoint of the interval, including: derating current interval, overcurrent interval, general short-circuit overcurrent interval, and severe short-circuit overcurrent interval.

[0011] Preferably, when the real-time current is within the derating current range, the first protection device is the vehicle controller, the second protection device is the contactor, and the first expected result is to reduce the real-time current to conform to the derating curve.

[0012] The control device is also configured as follows:

[0013] If the real-time current remains within the derating current range for a cumulative period of three preset durations, a derating request is sent to the vehicle controller, and the high-voltage power circuit current is adjusted based on the derating curve; and

[0014] If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the derating current range reaches the second preset time period, the second protection device is controlled to shut off the high-voltage power circuit.

[0015] Preferably, the first preset duration, the second preset duration, and the third preset duration are determined based on the battery pulse current characteristics of the high-voltage power circuit.

[0016] Furthermore, the derating current range is: [the rated current of the contactor, the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor].

[0017] Preferably, when the real-time current is within the overcurrent range, the first protection device is a contactor, the second protection device is a smart fuse, and the first expected result is to shut off the real-time current in the high-voltage power circuit.

[0018] The control device is also configured as follows:

[0019] If the real-time current remains in the overcurrent range for a cumulative period of time that reaches the third preset duration, then the first protection device will be controlled to shut off the high-voltage power circuit; and

[0020] If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is in the overcurrent range reaches the second preset time period, the second protection device is controlled to shut off the high-voltage power circuit.

[0021] Furthermore, the overcurrent range is defined as: [the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor, and the current value corresponding to the intersection of the bus power curve of the contactor and the power curve of the smart fuse].

[0022] Preferably, when the real-time current is within the general short-circuit overcurrent range, the first protection device is a smart fuse, the second protection device is a passive fuse, and the first expected result is to cut off the real-time current in the high-voltage power circuit.

[0023] The control device is also configured as follows:

[0024] If the real-time current remains within the normal short-circuit overcurrent range for a cumulative duration reaching the third preset duration, the intelligent fuse will be controlled to shut off the high-voltage power circuit; and

[0025] If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the general short-circuit overcurrent range reaches the second preset time period, the passive fuse will be controlled to shut off the high-voltage power circuit.

[0026] Furthermore, the general short-circuit overcurrent range is: [the current value corresponding to the intersection of the contactor's bus power curve and the smart fuse's power curve, and the current value corresponding to the intersection of the smart fuse's bus power curve and the passive fuse's power curve].

[0027] Preferably, when the real-time current is in the severe short-circuit overcurrent range, the first protection device is a passive fuse, the second protection device is an intelligent fuse, and the first expected result is to shut off the real-time current in the high-voltage power circuit.

[0028] The control device is also configured as follows:

[0029] If the real-time current remains in the severe short-circuit overcurrent range for a cumulative duration reaching the third preset duration, the passive fuse will be controlled to shut off the high-voltage power circuit; and

[0030] If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is in the severe short-circuit overcurrent range reaches the second preset time period, the intelligent fuse will be controlled to shut off the high-voltage power circuit.

[0031] Furthermore, the severe short-circuit overcurrent range [the current value corresponding to the intersection of the bus power curve of the smart fuse and the power curve of the passive fuse, ∞).

[0032] Preferably, the third preset duration is less than the second preset duration.

[0033] Preferably, the control device is further configured to: if the real-time current is not within the current protection range, and the current shutdown device cannot shut down the high-voltage power circuit within a first preset time period, shut down the high-voltage power circuit through the second protection device.

[0034] By using the above technical solution, a corresponding first protection device and a second protection device are set for each different current protection range. When the first protection device cannot effectively reduce the overcurrent risk in the high-voltage power circuit, the high-voltage power circuit can be shut off in time by the second protection device, which can reduce the safety risk of the high-voltage power circuit under overcurrent or short circuit conditions.

[0035] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0036] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0037] Figure 1 This is a circuit diagram of an embodiment of the high-voltage power system of the present invention;

[0038] Figure 2 This is a circuit diagram of another embodiment of the high-voltage power system of the present invention;

[0039] Figure 3 yes Figure 2 A schematic diagram of the derating curve in the embodiment;

[0040] Figure 4 yes Figure 2 A schematic diagram illustrating the setting of various current protection zones in the embodiment;

[0041] Figure 5 yes Figure 3 A schematic diagram showing the setting of equipment shutdown waiting time based on the setting of each current protection interval; and

[0042] Figure 6 yes Figure 2 A schematic diagram of the switching between the main shutdown and standby shutdown devices in the derating current range of the embodiment. Detailed Implementation

[0043] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0044] This invention provides a high-voltage power system, the circuit of which is as follows: Figure 1 As shown, it includes: a high-voltage power circuit and a control device, wherein the high-voltage power circuit is provided with a first protection device and a second protection device; the control device is configured to: when the real-time current in the high-voltage power circuit is within a preset current protection range, control the current in the high-voltage power circuit to achieve a first expected result through the first protection device corresponding to the current protection range; and if the first expected result cannot be achieved within a first preset time period through the first protection device, or if the cumulative time of the real-time current within the current protection range reaches a second preset time period, then shut down the high-voltage power circuit through the second protection device corresponding to the current protection range.

[0045] In this embodiment, the high-voltage power circuit can be the high-voltage power circuit of an electric vehicle using a power battery. The high-voltage power circuit includes a power battery pack, electrical equipment, and protection devices to prevent arcing caused by short circuits, overloads, overcurrents, etc. When the real-time current in the high-voltage power circuit is within a preset current protection range, the first protection device is used to handle the safety risks in the high-voltage power circuit first. If the first protection device fails, the second protection device shuts off the high-voltage power circuit.

[0046] It should be noted that as the current in the high-voltage power circuit increases, the overcurrent capacity of the high-voltage electrical system gradually weakens, and the risk of burnout and arcing increases. Therefore, based on the rated overcurrent capacity of the high-voltage harness and its connection points, and characteristic parameters such as the rated current or power curves of different protection devices, different current protection ranges are determined, and corresponding first and second protection devices are set for different current protection ranges to determine the response plan under different risk levels.

[0047] Specifically, for the preset current protection range, if the first protection device fails to effectively reduce the current in the high-voltage power circuit within a first preset time period, or if the cumulative time for which the real-time current in the high-voltage power circuit is within the current protection range reaches a second preset time period, the high-voltage power circuit will be shut down by the second protection device corresponding to that current protection range. The first and second preset time periods should be determined based on the battery pulse current characteristics of the high-voltage power circuit, and the first preset time period should be less than the second preset time period. That is to say, either the following scheme one can be used for overcurrent control: the first protection device should be used first to reduce or shut down the current in the high-voltage power circuit; if the current in the high-voltage power circuit is not effectively reduced or shut down within the first preset time period, the second protection device should be immediately controlled to shut down the high-voltage power circuit; or the following scheme two can be used for overcurrent control: regardless of whether the first protection device is functioning normally, as long as the cumulative time for which the real-time current in the high-voltage power circuit is within the current protection range reaches the second preset time period, the second protection device should be immediately controlled to shut down the high-voltage power circuit.

[0048] More specifically, the current protection intervals are arranged in ascending order of the left endpoint value and / or right endpoint value, including: derating current interval, overcurrent interval, general short-circuit overcurrent interval, and severe short-circuit overcurrent interval. The current risk level is determined based on the current magnitude within the current protection intervals, and corresponding first and second protection devices are then set accordingly. When the real-time current is within the derating current interval, the first protection device is the vehicle controller, and the second protection device is a contactor. According to the request of the control device of this application, the vehicle controller reduces the real-time current to meet the derating curve. If the vehicle controller cannot effectively reduce the real-time current to meet the derating curve in a timely manner, the control device of this application controls the contactor to shut off the real-time current in the high-voltage power circuit. When the real-time current is within the overcurrent interval, the first protection device is a contactor, and the second protection device is a smart fuse. According to the instruction of the control device of this application, the contactor shuts off the real-time current in the high-voltage power circuit. If the contactor cannot effectively shut off the high-voltage power circuit in a timely manner, the control device of this application controls the smart fuse to actively blow to shut off the circuit. The system interrupts the real-time current in the high-voltage power circuit. When the real-time current is within the general short-circuit overcurrent range, the first protection device is a smart fuse, and the second protection device is a passive fuse. According to the instructions of the control device of this application, the smart fuse actively blows to shut off the real-time current in the high-voltage power circuit. If the smart fuse fails to blow in time, the passive fuse should passively blow after a second preset time period. When the real-time current is within the severe short-circuit overcurrent range, the first protection device is a passive fuse, and the second protection device is a smart fuse. If the passive fuse does not passively blow within the first preset time period, the control device of this application should control the smart fuse to actively blow after a second preset time period to shut off the real-time current in the high-voltage power circuit.

[0049] It should be noted that the smart fuse in this application, also known as an active fuse, is a protective device that actively disconnects the circuit. It is typically used to protect high-precision, high-level circuits, such as semiconductor devices and ICs. Active fuses usually employ thermocouples or photocouples to monitor circuit temperature or light intensity when the circuit is overloaded and quickly disconnect the circuit for protection. The smart fuse has a single tripping time; as the overcurrent time increases, the fuse response time gradually decreases, and the protective current can cover large currents to peak currents, for example, 900A to 10000A. The passive fuse in this application, also known as a passive circuit breaker, is a protective device that automatically melts when the circuit is overloaded. A passive circuit breaker typically consists of a conductor and a fuse wire. When the current in the circuit exceeds its carrying capacity, the fuse wire melts, thereby cutting off the circuit and protecting the electrical equipment. The passive fuse has a single tripping time, and the protective current can cover 0A to the maximum current, for example, 1500A to 10000A. Technicians should set the fusing parameters of active and passive fuses based on parameters such as the load of the high-voltage circuit, the rated overcurrent capacity of the high-voltage wiring harness and its connection points, the maximum current of the vehicle during continuous operation, and the peak current of the battery pack short circuit within a time that will not damage the battery, so that the active and passive fuses can be blown within the preset current range.

[0050] It should also be noted that the derating curve is a time-related pulse charging current and pulse discharging current defined by the battery supplier based on the battery's charging or discharging characteristics, i.e., the maximum allowable charging current or discharging current. In existing technology, the battery management system issues the maximum allowable charging or discharging current of the battery to the vehicle based on the derating curve and requires that the vehicle's electric drive load not exceed the derating curve. For example, a 1-second pulse current can reach 500A to 700A, a 3-second pulse current can reach 400A to 600A, a 10-second pulse current can reach 350A to 500A, and a constant current can reach 300A to 450A. A contactor uses electromagnetic, pneumatic, or hydraulic principles to control the switching of the main circuit. The main characteristics of a contactor include strong current interruption capability, rapid action, safe operation, frequent operation, and remote control. The contactor can support an unlimited number of cut-offs at low current (e.g., around 20A). As the current increases, the number of cut-offs under load gradually decreases. The protection current can cover from 0A to the maximum load current, for example, from 0A to 1500A.

[0051] Technicians can select the parameters of the derating curve, contactor, smart fuse, and passive fuse based on the load characteristics of the high-voltage power circuit, and then set the left and right endpoints between the current protection zones based on the parameters of the derating curve, contactor, smart fuse, and passive fuse. In one embodiment, the derating current range is: [the rated current of the contactor, the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor); the overcurrent range is: [the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor, the current value corresponding to the intersection of the bus power curve of the contactor and the power curve of the smart fuse); the general short-circuit overcurrent range is: [the current value corresponding to the intersection of the bus power curve of the contactor and the power curve of the smart fuse, the current value corresponding to the intersection of the bus power curve of the smart fuse and the power curve of the passive fuse); the severe short-circuit overcurrent range is [the current value corresponding to the intersection of the bus power curve of the smart fuse and the power curve of the passive fuse, ∞].

[0052] Compared with the prior art, the technical advantages of this embodiment are as follows:

[0053] 1. A dual protection device is adopted to reduce the overcurrent risk of the high-voltage power circuit. When the first protection device cannot handle the risk situation in time, the high-voltage power circuit can be shut off in time through the second protection device.

[0054] 2. Different levels of current protection ranges and protection devices are set up accordingly. When different levels of overcurrent risk occur, the corresponding protection devices can protect the high-voltage power circuit and even the safety of the whole vehicle in a timely manner.

[0055] The following combination Figure 2-6 The description further explains how the high-voltage power system of this application works. Each protection device should be connected to the high-voltage circuit in series, such as... Figure 2 As shown, the main fuse (i.e., passive protection), smart fuse, according to Figure 3 The derating curve shown indicates that the vehicle controller (not shown), contactor, and battery are connected in series to control the circuit current. Therefore, any shut-off device can shut off the high-voltage circuit. However... Figure 2 This is merely an example; the connection order of different shutdown devices is not limited in this invention.

[0056] In this embodiment, the following settings are made: Figure 3 As shown, the rated current of the contactor is used respectively ( Figure 4 The current value corresponding to the intersection of the bus power curve and the contactor power curve of the high-voltage power circuit (I0). Figure 4 The current value corresponding to the intersection of the contactor's bus power curve and the smart fuse power curve (I1) Figure 4 The current value corresponding to the intersection of the bus power curve of the intelligent fuse and the power curve of the passive fuse (I2). Figure 4I3) sets the rated current range, derating current range, overcurrent range, general short-circuit overcurrent range and severe short-circuit overcurrent range for the critical point.

[0057] Among them, the rated current range is considered to be the current range under normal operating conditions of the high-voltage power circuit. The derating current range, overcurrent range, general short-circuit overcurrent range, and severe short-circuit overcurrent range are all risk ranges with overcurrent risk, and the risk increases in that order, requiring the corresponding risk to be dealt with in a shorter time.

[0058] In this embodiment, the current protection range is as follows: Figure 5 As shown, the current range in the range [0, I0) is called the rated current range. The shut-off device is a contactor, which is controlled to turn on or off according to the normal working requirements of the high-voltage power circuit.

[0059] The current range [I0, I1) is called the derating current range. The first protection device is based on... Figure 3 The vehicle controller, which controls the current in the derating curve shown, uses a contactor as the second protection device. If the real-time current remains in the derating current range for a cumulative period of a third preset duration, the control device of this application requests the vehicle controller to reduce the real-time current in the power circuit. The vehicle controller reduces the real-time current in the power circuit, for example, by shutting down certain loads or reducing the power supply voltage. If the real-time current cannot meet the requirements within the first preset duration, the control device will not provide further protection. Figure 3 If the derating curve shown, or the cumulative duration of the real-time current in the derating current range reaches the second preset duration, the contactor will be controlled by the control device of this application to shut off the high-voltage power circuit to prevent safety accidents caused by prolonged overcurrent.

[0060] The current range [I1, I2) is called the overcurrent range. The first protection device is a contactor, and the second protection device is a smart fuse. If the cumulative duration of the real-time current in the overcurrent range reaches a third preset duration, the control device of this application controls the contactor to shut off the high-voltage power circuit. If the contactor cannot shut off the high-voltage power circuit within the first preset duration, or if the cumulative duration of the real-time current in the overcurrent range reaches the second preset duration, the control device of this application controls the smart fuse to blow, thereby shutting off the high-voltage power circuit and preventing safety accidents caused by overcurrent.

[0061] The current in the range [I2, I3) is called the general short-circuit overcurrent range. The first protection device is a smart fuse, and the second protection device is a main fuse. If the cumulative duration of the real-time current in the general short-circuit overcurrent range reaches the third preset duration, the control device of this application controls the smart fuse to blow. If the smart fuse cannot blow within the first preset duration, or if the cumulative duration of the real-time current in the general short-circuit current range reaches the second preset duration, the main fuse should be passively blown to shut off the high-voltage power circuit, thereby preventing safety accidents caused by general short circuits.

[0062] The current range [I3,∞) is called the severe short-circuit overcurrent range. The first protection device is the main fuse, and the second protection device is the smart fuse. If the cumulative duration of the real-time current in the severe short-circuit overcurrent range reaches the third preset duration, the main fuse should blow within the first preset duration. If the main fuse fails to blow within the first preset duration, or if the cumulative duration of the real-time current in the severe short-circuit current range reaches the second preset duration, the control device of this application controls the smart fuse to blow, thereby shutting off the high-voltage power circuit and preventing safety accidents caused by severe short circuits.

[0063] It should be noted that for a certain current protection interval, the first preset time period, the second preset time period, and the third preset time period are determined based on the battery pulse current characteristics of the high-voltage power circuit; for different current protection intervals, the first preset time period, the second preset time period, and the third preset time period should be set separately according to the current protection interval; the first preset time period is shorter than the second preset time period; the third preset time period is shorter than the second preset time period.

[0064] It should also be noted that if the real-time current in the circuit is not within the current protection range, i.e., if the circuit is not considered to have an overcurrent risk, and if the current shut-off device cannot shut off the high-voltage power circuit within the first preset time period, the high-voltage power circuit should also be shut off through the second protection device to prevent other safety risks.

[0065] The following combination Figure 5 and Figure 6 This explains how to set up the first and second protection devices and the first, second and third preset time periods in different current protection ranges to achieve phased protection, avoid the inability to shut down the high voltage circuit in time, and ensure the safety of the electric vehicle's electrical system.

[0066] When the high-voltage circuit current is greater than I0 and less than I1, meaning the actual current of the high-voltage power circuit is within the derating current range, the vehicle controller limits the available current to the lower left of the derating curve e. If the actual current is higher than the derating curve e and exceeds the allowable time t0_1, a derating request is made to the vehicle controller. If the derating exceeds the timeout t0_2, the high-voltage power circuit is shut off using a contactor. t0_1 and t0_2 are the confirmation time for normal power limiting and the timeout for standby equipment response, respectively.

[0067] When the high-voltage circuit current is greater than I1 and less than I2, and exceeds the allowable time t1_1, meaning the actual current of the high-voltage power circuit is in the overcurrent range, the first protection device (contactor) acts as the main shut-off device. If the shut-off timeout t1_2 occurs, the second protection device (smart fuse) becomes the backup shut-off device. t1_1 and t1_2 are the confirmation time of the main shut-off device and the timeout period for the backup device to respond, respectively.

[0068] When the high-voltage circuit current is greater than I2 and less than I3, and exceeds the allowable time t2_1, meaning the actual current of the high-voltage power circuit is within the general short-circuit overcurrent range, the first protection device (smart fuse) acts as the primary shutdown device. If the shutdown timeout t2_2 occurs, the second protection device (passive fuse) becomes the backup shutdown device. t2_1 and t2_2 represent the confirmation time of the primary shutdown device and the timeout period for the backup device to respond, respectively.

[0069] When the high-voltage circuit current exceeds I3 and the allowable time t3_1 is exceeded, meaning the actual current of the high-voltage power circuit is in the severe short-circuit overcurrent range, the second protection device (passive fuse) acts as the primary shutdown device. If the shutdown timeout t3_2 occurs, the second protection device (smart fuse) becomes the backup shutdown device. t3_1 and t3_2 represent the confirmation time of the primary shutdown device and the timeout period for the backup device to respond, respectively.

[0070] Table 1 below shows the confirmation time of the main shutdown device and the timeout time of the backup device response waiting in different current protection ranges obtained from actual battery testing according to this embodiment.

[0071] Table 1

[0072]

[0073]

[0074] As can be seen from the table above, the risk of overcurrent or short-circuit overcurrent increases with increasing current. Therefore, it is necessary to set appropriate shutdown devices and establish waiting times for these devices. When the current exceeds the set waiting time within the corresponding current protection range, the appropriate shutdown device should be activated. For example... Figure 6As shown, within the derating current range, t0_1 and t0_2 represent the confirmation time for normal power limiting and the timeout for standby equipment response, respectively, or the switching waiting time between the main shutdown and standby shutdown equipment within the derating current range. It should be noted that the active fuse selection in the table above considers the main fuse response time, which is generally <2ms, and the material is bus-bar, therefore the overcurrent is very high, and its fusing curve is relatively high. Passive fuse selection mainly considers two aspects: 1. The maximum continuous operating current of the entire vehicle, generally 1.2 to 1.5 times the rated current of the vehicle; 2. The peak current during a battery pack short circuit and the time without damage to the battery, generally 3000A within 100ms for a 500V battery.

[0075] It should be noted that the waiting time of the first protection device in Table 1 above is the third preset time in this application, and the waiting time of the second protection device is the second preset time in this application. That is to say, when the cumulative time the real-time current is within the current range reaches the third preset time, the first protection device begins to perform current reduction or shutdown operations. If the first protection device cannot complete the current reduction or shutdown operations within the second preset time, the second protection device shuts off the high-voltage power circuit when the cumulative time the real-time current is within the current range reaches the second preset time. Technical personnel can refer to Table 1 to set the first, second, and third preset times corresponding to the current range and the first and second protection devices according to the circuit characteristics of the high-voltage circuit.

[0076] It should also be noted that the current range in Table 1 above, which is in the range of [0, I0), is the rated current range. The shut-off device is a contactor, which is controlled to turn on or off according to the normal operation requirements of the high-voltage power circuit.

[0077] In some embodiments, an excitation protection device is also included, comprising an execution part and a control part, applied to the high-voltage electrical circuit of an electric vehicle; the high-voltage electrical circuit of the electric vehicle includes a power part, a load part, a wiring harness connection part, and a high-voltage control part, wherein the power part mainly includes a power battery, a supercapacitor, or a fuel cell system, the load part includes a motor and its control system, and a high-voltage accessory part, the wiring harness connection part mainly includes a high-voltage wiring harness and its connector, and the high-voltage control part includes an excitation fuse and its execution device, as well as a high-voltage circuit relay and its control device.

[0078] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0079] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A high-voltage power system, characterized in that, It includes a high-voltage power circuit and a control device, wherein the high-voltage power circuit is equipped with a first protection device and a second protection device; The control device is configured to: When the real-time current in the high-voltage power circuit is within a preset current protection range, the first protection device corresponding to the current protection range controls the current in the high-voltage power circuit to achieve a first expected result; and If the first expected result cannot be achieved within a first preset time period through the first protection device, or if the cumulative time during which the real-time current is within the current protection range reaches a second preset time period, then the high-voltage power circuit will be shut off through the second protection device corresponding to the current protection range. The current protection intervals, in ascending order of the left endpoint value and / or the right endpoint value, include: rated current interval, derating current interval, overcurrent interval, general short-circuit overcurrent interval, and severe short-circuit overcurrent interval. Specifically, the rated current range, the derating current range, the overcurrent range, the general short-circuit overcurrent range, and the severe short-circuit overcurrent range are defined with the following critical points: the rated current of the contactor, the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor, the current value corresponding to the intersection of the bus power curve of the contactor and the power curve of the smart fuse, and the current value corresponding to the intersection of the bus power curve of the smart fuse and the power curve of the passive fuse. The derating current range is defined as: greater than or equal to the rated current of the contactor, and less than the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor. The overcurrent range is defined as: greater than or equal to the current value corresponding to the intersection of the bus power curve of the high-voltage power circuit and the power curve of the contactor, and less than the current value corresponding to the intersection of the bus power curve of the contactor and the power curve of the smart fuse. The general short-circuit overcurrent range is: greater than or equal to the current value corresponding to the intersection of the contactor's bus power curve and the power curve of the smart fuse, and less than the current value corresponding to the intersection of the smart fuse's bus power curve and the power curve of the passive fuse. The severe short-circuit overcurrent range is defined as the current value at the intersection of the bus power curve of the smart fuse and the power curve of the passive fuse, which is greater than or equal to that value.

2. The high-voltage power system according to claim 1, characterized in that, The first preset duration is less than the second preset duration.

3. The high-voltage power system according to claim 1, characterized in that, When the real-time current is within the derating current range, the first protection device is a vehicle controller, the second protection device is a contactor, and the first expected result is to reduce the real-time current to conform to the derating curve. The control device is also configured to: If the real-time current is in the derating current range for a cumulative duration of a third preset duration, a derating requirement is requested from the vehicle controller, and the high-voltage power circuit current is adjusted based on the derating curve. and If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the derating current range reaches the second preset time period, the second protection device is controlled to shut off the high-voltage power circuit.

4. The high-voltage power system according to claim 3, characterized in that, The first preset duration, the second preset duration, and the third preset duration are determined based on the battery pulse current characteristics of the high-voltage power circuit.

5. The high-voltage power system according to claim 1, characterized in that, When the real-time current is within the overcurrent range, the first protection device is a contactor, the second protection device is a smart fuse, and the first expected result is to shut off the real-time current in the high-voltage power circuit. The control device is also configured to: If the real-time current is in the overcurrent range for a cumulative period of time that reaches a third preset duration, then the first protection device is controlled to shut off the high-voltage power circuit. and If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the overcurrent range reaches the second preset time period, the second protection device is controlled to shut off the high-voltage power circuit.

6. The high-voltage power system according to claim 1, characterized in that, When the real-time current is within the general short-circuit overcurrent range, the first protection device is a smart fuse, the second protection device is a passive fuse, and the first expected result is to shut off the real-time current in the high-voltage power circuit. The control device is also configured to: If the real-time current is in the general short-circuit overcurrent range for a cumulative duration of a third preset duration, then the smart fuse is controlled to shut off the high-voltage power circuit. and If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the general short-circuit overcurrent range reaches the second preset time period, the passive fuse is controlled to shut off the high-voltage power circuit.

7. The high-voltage power system according to claim 1, characterized in that, When the real-time current is within the severe short-circuit overcurrent range, the first protection device is a passive fuse, the second protection device is a smart fuse, and the first expected result is to shut off the real-time current in the high-voltage power circuit. The control device is also configured to: If the real-time current is in the severe short-circuit overcurrent range for a cumulative duration of a third preset duration, then the passive fuse is controlled to shut off the high-voltage power circuit. and If the first expected result cannot be achieved within the first preset time period, or if the cumulative time during which the real-time current is within the severe short-circuit overcurrent range reaches the second preset time period, the smart fuse is controlled to shut off the high-voltage power circuit.

8. The high-voltage power system according to any one of claims 3, 5, 6, and 7, characterized in that, The third preset duration is less than the second preset duration.

9. The high-voltage power system according to claim 1, characterized in that, The control device is also configured to: If the real-time current is not within the current protection range, and the current shutdown device cannot shut down the high-voltage power circuit within the first preset time period, the high-voltage power circuit is shut down by the second protection device.

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