High-voltage power distribution protection system, power distribution cabinet and vehicle

Abstract

The invention belongs to the technical field of high-voltage power distribution protection, and particularly relates to a high-voltage power distribution protection system, a power distribution cabinet and a vehicle. The system comprises a first circuit, a second circuit, a third circuit, a first branch circuit and a second branch circuit, wherein the first circuit, the second circuit and the third circuit are connected in parallel; the first branch circuit and the second branch circuit are connected with the first branch circuit in parallel, the power distribution protection system can enable the power distribution protection controller to be powered on through the first circuit when a driver closes the main switch, and the power distribution protection controller can be awakened through the third circuit after the ignition lock is powered on; after being awakened, the power distribution protection controller can control the low-voltage power supply interlocking relay to be closed, so that the low-voltage power supply is directly connected with the power distribution protection controller through the second circuit, the power distribution protection controller can still keep electrified after a driver turns off the main switch, and a high-voltage related controller is controlled through the first branch circuit and the second branch circuit. And the high-voltage contactor of the high-voltage electrical appliance is controlled through the high-voltage control port to meet the delay requirement and avoid on-load breaking.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-voltage power distribution protection, and particularly relates to a high-voltage power distribution protection system, a power distribution cabinet and a vehicle. Background Art

[0002] Regarding high-voltage power-off protection in the prior art, the vehicle control unit (VCU) is often used to control a low-voltage delay relay to manage the power-off time of the vehicle's low-voltage working power, ensuring sufficient time for functions such as position memory of the gearshift, motor, etc., and battery data storage of the battery management system (BMS) to be completed, and ensuring that the MCU actively powers off. However, it cannot protect against forced power-off behaviors such as quickly disconnecting the low-voltage power main switch after the driver powers off, resulting in some high-voltage systems being disconnected under load. This has the greatest impact on systems that require a long working process after power-off; for example, it has an adverse effect on the hydrogen system's power-off water vapor purging and the dust removal and back-blowing systems of the heat dissipation systems such as power and battery cooling, and even affects the service life of the high-voltage relay contacts and various high-voltage systems such as hydrogen and the transmission. Moreover, in the face of faults caused by abnormal situations such as loose connections and communication interference in the controller's circuits, there is often a lack of response mechanisms, which also easily leads to the drawback of directly disconnecting under load after the high-voltage contactor loses the correct and effective control instructions from the external controller. A better technical solution is needed to solve the above various adverse technical difficulties.

[0003] The high-voltage power distribution system does not permit abnormal power-off under load. The load-breaking of the contactor will cause arc ablation of the contacts. The ablation points caused by multiple load-breaking affect the contact resistance value and current-carrying capacity of the contacts, easily leading to adverse results such as too high contact resistance, heat generation, and thermal fusion adhesion, which affect the service life of the contactor.

[0004] Load-breaking the high-voltage circuit will also bring a large reverse electromotive force to the inductive load circuit, damaging the controller, electrical appliances, and all components of their high-voltage circuits. In the traditional high-low voltage design method, the low-voltage power supply of all controllers can be cut off through the low-voltage power main switch, there is a risk of quickly closing the low-voltage power main switch immediately after the driver turns off the ignition lock. Even through the low-voltage power-off delay function of controllers such as VCU, it only maintains the delay control of the low-voltage power supply of the core controller after the key is turned off at the program level, but still cannot avoid the risk of load-breaking caused by the artificial disconnection of the low-voltage power main switch, and cannot prevent power supply interruption or communication interruption caused by various accidents during driving and maintenance, such as virtual connection, accidental damage, or loose contact of the low-voltage power supply interfaces of various control devices, and the resulting load-breaking, vehicle risks, and equipment adhesion and impact damage caused by the interruption of the relay control signal.

[0005] Since the high-voltage contactor is arranged in the power distribution cabinet (high-voltage power distribution cabinet PDU or battery power distribution cabinet BDU), and these two types of power distribution cabinets usually do not have the initiative to control the relay. Instead, controllers such as VCU or BMS control according to logic. And the low-voltage control electrode depends on the normal effectiveness of the delay circuit of the manual main power switch and controllers with delay power-off functions such as VCU. Any accidental power-off or loss and disorder of communication control instructions will cause the power distribution cabinet to get out of control and unable to be protected, resulting in a load-breaking accident. Summary of the Invention

[0006] The purpose of the present invention is to provide a high-voltage power distribution protection system, a power distribution cabinet and a vehicle. When the driver closes the main switch, the power distribution protection controller can be powered on through the first circuit and be in a standby state that can be awakened at any time. After the ignition lock is powered on, the power distribution protection controller can be awakened through the third circuit. After the power distribution protection controller is awakened, it can control the low-voltage power interlock relay to close, so that the low-voltage power is directly connected to the power distribution protection controller through the second circuit. After the main switch or the ignition lock is disconnected, the power distribution protection controller can still be powered on through the second circuit, so as to perform delay control on the high-voltage related controllers through the first branch and the second branch. At the same time, the high-voltage contactor of the high-voltage electrical appliance can be controlled through the high-voltage control port to meet the delay requirements of the high-voltage electrical appliance and avoid load-breaking.

[0007] To achieve the above object, the present invention adopts the following technical solutions to solve: In the first aspect, the present invention provides a high-voltage power distribution protection system, which includes: A first circuit, which is connected from the low-voltage power supply through the main switch to the initial constant power interface of the power distribution protection controller. The high-voltage control port of the power distribution protection controller is connected to the high-voltage contactor of the high-voltage electrical appliance; A second circuit, which is connected from the low-voltage power supply through the contacts of the low-voltage power interlock relay to the extended constant power interface of the power distribution protection controller; A third circuit, which is connected from the low-voltage power supply through the main switch and the contacts of the vehicle ON power relay to the wake-up interface of the power distribution protection controller. The first circuit, the second circuit and the third circuit are connected in parallel with each other; A first branch, which is connected from the second circuit downstream of the low-voltage power interlock relay through the contacts of the low-voltage interlock constant power relay to the high-voltage related controller; The first branch downstream of the low-voltage interlock constant power relay is also connected to the first circuit downstream of the main switch; A second branch, which is connected in parallel with the first branch. The second branch is connected from the second circuit downstream of the low-voltage power interlock relay through the contacts of the low-voltage interlock ON power relay to the high-voltage related controller; The second branch downstream of the low-voltage interlock ON power relay is connected to the third circuit downstream of the low-voltage interlock ON power relay; The low-voltage power interlock relay, the low-voltage interlock constant power relay, and the low-voltage interlock ON power relay are respectively connected to the corresponding control interfaces on the distribution protection controller, and the vehicle ON power relay is controlled by the ignition lock ON power.

[0008] Optionally, it further includes: A third branch, where the first circuit downstream of the main switch is connected to the low-voltage electrical appliances.

[0009] Optionally, it further includes: A fourth branch, where the third circuit downstream of the vehicle ON power relay is connected to the low-voltage electrical appliances and the low-voltage related controllers.

[0010] Optionally, it further includes: A low-voltage status indicator light, connected to the distribution protection controller; The low-voltage status indicator light is configured to flash when the main switch is closed, indicating that the distribution protection controller has been powered on and is in the standby state; The low-voltage status indicator light is further configured to be constantly on when the main switch, the low-voltage power interlock relay, the low-voltage interlock constant power relay, and the low-voltage interlock ON power relay are all closed, indicating that the distribution protection controller outputs dedicated constant power and wakes up the ON power to the high-voltage related controllers and is in the power protection state.

[0011] Optionally, it further includes: A high-voltage status indicator light, connected to the distribution protection controller; The high-voltage status indicator light is configured to be constantly on when the vehicle has been ignited and started and the positive and negative contactors of any high-voltage circuit of the vehicle are closed, indicating that the distribution protection controller is in the high-voltage protection state; When the distribution protection controller is in the high-voltage protection state, it can maintain power on by using the conventional constant power provided by the first circuit, the delayed constant power provided by the second circuit, or the protection constant power provided by the first branch connecting the first circuit. The distribution protection controller can also provide dedicated constant power and wake-up ON power to the high-voltage related controllers through the first branch and the second branch respectively, and perform delayed control on the high-voltage contactors corresponding to the high-voltage electrical appliances according to the delayed requirements of the high-voltage electrical appliances through the high-voltage control interface. The closing sequence after the delayed control ends is the low-voltage interlock ON power relay, the low-voltage interlock constant power relay, and the low-voltage power interlock relay.

[0012] Optionally, the high-voltage related controllers include the VCU and the BMS.

[0013] Optionally, it further includes: A charging compensation controller, including a first interface, a second interface, and a third interface; The first interface is connected to the first circuit upstream of the low-voltage power interlock relay to detect the battery direct connection voltage; The second interface is connected to the VCU and the BMS, and is used to enable the VCU and the BMS to enter a power replenishment mode when the battery direct connection voltage is lower than a preset threshold; The third interface is connected in parallel to the DCDC converter and the power distribution protection controller, and is used to give a DC operation enable and enable the power distribution protection controller to enter a power replenishment mode when the battery direct connection voltage is lower than a preset threshold.

[0014] Optionally, it also includes: A power supply status indicator light connected to the power distribution protection controller; The charging status indicator light is configured to be always on when the vehicle is in the charging mode and the positive and negative contactors of any high-voltage circuit are closed. If the vehicle is also in the non-ignition state at the same time, the charging status indicator light flashes.

[0015] In a second aspect, the present invention provides a power distribution cabinet, which includes the above-mentioned high-voltage power distribution protection system.

[0016] In a third aspect, the present invention provides a vehicle, which includes the above-mentioned high-voltage power distribution protection system.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The power distribution cabinet in the present invention has its own power distribution protection controller, which can use the low-voltage power supply to achieve stable low-voltage power supply through the first circuit and the second circuit, rather than relying on external delayed power supply, to ensure the absolute stability of the power supply system. In addition, the power distribution protection controller can also delay the control of the high-voltage contactor of the high-voltage circuit to meet the delay requirements of high-voltage electrical appliances (such as the hydrogen system's water vapor blowing and the power and battery cooling system's dust removal and back-blowing system) under the premise of maintaining low-voltage stable power supply. The power distribution protection controller of the present invention can still be powered on through a low-voltage power supply in the abnormal situation that the main switch is accidentally turned off, and control and monitor the high-voltage contactor of the high-voltage circuit according to the high-voltage control port to perform power-off control (including delay control and closing each relay in sequence) to ensure safety.

[0018] 2. The power distribution protection system of the present invention has the ability to provide stable power supply to high-voltage related controllers (VCU / BMS). High-voltage related controllers and high-voltage electrical appliances and systems that require delay will not be affected by accidental human shutdown of the main switch. Drivers can also rest assured to cut off power in time without having to wait for a long time, and can ensure controllable and reasonable delay in power off, making the power distribution system and vehicle operation more humane. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of the high-voltage power distribution protection system in Example 1. DETAILED DESCRIPTION

[0020] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0021] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention. Embodiment 1

[0022] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0023] Combined with Figure 1 , this embodiment provides a high-voltage power distribution protection system. The power distribution protection system includes a low-voltage power supply, a power distribution cabinet (high-voltage power distribution cabinet PDU or battery power distribution cabinet BDU), high-voltage electrical appliances, high-voltage related controllers (vehicle controller VCU and battery management system BMS), low-voltage electrical appliances and low-voltage related controllers. Among them, the power distribution cabinet includes a power distribution protection controller, protection relays (low-voltage power supply interlock relay, low-voltage interlock ON power relay and low-voltage interlock constant power relay), and a plurality of anti-cross-current diodes. The high-voltage control port of the power distribution protection controller is connected to the high-voltage contactor of the high-voltage electrical appliance to control the opening and closing of the high-voltage contactor.

[0024] The distribution protection controller of this embodiment can still be electrically connected to the low-voltage power supply after the vehicle is turned off and the main switch is disconnected by controlling each protection relay, so as to delay the control of the high-voltage contactor of the high-voltage circuit through the distribution protection controller, thereby avoiding the situation that the high-voltage contactor suddenly loses control and powers off when the vehicle accidentally stalls or the main switch is suddenly disconnected, resulting in the load-breaking of high-voltage electrical appliances.

[0025] The distribution protection system further includes a first circuit, a second circuit, a third circuit, a first branch, a second branch, a third branch and a fourth branch. The first circuit is connected from the low-voltage power supply through the main switch to the initial constant-power interface (J port or J pin) of the distribution protection controller. The first circuit is used to provide initial constant power for the distribution protection controller when the main switch is closed. The main switch is usually manually operated by the driver. The second circuit is connected from the low-voltage power supply through the contacts of the low-voltage power supply interlock relay to the extended constant-power interface (H port or H pin) of the distribution protection controller; the third circuit is connected from the low-voltage power supply through the main switch and the contacts of the vehicle ON power relay to the wake-up interface (K port or K pin) of the distribution protection controller. The first circuit, the second circuit and the third circuit are connected in parallel with each other; the first branch is connected from the second circuit downstream of the low-voltage power supply interlock relay through the contacts of the low-voltage interlock constant-power relay to the high-voltage related controller; the first branch downstream of the low-voltage interlock constant-power relay is also connected to the first circuit downstream of the main switch. The second branch is connected in parallel with the first branch. The second branch is connected from the second circuit downstream of the low-voltage power supply interlock relay through the contacts of the low-voltage interlock ON power relay to the high-voltage related controller; the second branch downstream of the low-voltage interlock ON power relay is also connected to the third circuit downstream of the low-voltage interlock ON power relay. The third branch is connected from the first circuit downstream of the main switch to the low-voltage electrical appliance. The fourth branch is connected from the third circuit downstream of the vehicle ON power relay to the low-voltage electrical appliance and the low-voltage related controller.

[0026] Among them, the coil of the low-voltage power supply interlock relay is driven and controlled by the I pin of the distribution protection controller (the driving method can be selected as high-side driving or low-side driving, depending on the pin resources of the controller, and is not uniquely limited); the low-voltage interlock constant-power relay and the low-voltage interlock ON power relay are respectively driven and controlled by the F pin and G pin of the distribution protection controller. The vehicle ON power relay is controlled by the ignition lock ON power.

[0027] The first circuit of this embodiment is used to provide low-voltage constant power for the power distribution protection controller. Specifically, after the first circuit is connected from the low-voltage power supply to the main switch, it can output to the low-voltage electrical appliances and low-voltage related controllers through the third branch. At the same time, it is connected in parallel to port D of the power distribution cabinet and connected to the initial constant power interface (J port) of the power distribution protection controller through the anti-cross-current diode 5 to serve as the initial constant power to power on the power distribution protection controller. After the power distribution protection controller is powered on by the initial constant power, it can be regarded as being in a standby state ready to respond at any time to be awakened.

[0028] When the ignition lock is turned to the ON position, it outputs an ignition lock ON power control signal to the vehicle ON power relay coil and closes the contact. The low-voltage power supply can output low-voltage ON power to the wake-up interface of the power distribution protection controller through the third circuit. Specifically, the low-voltage constant power after the main switch is fed from port E of the power distribution cabinet, and then connected to the K pin of the power distribution protection controller through the anti-cross-current diode 6 to serve as the wake-up signal of the power distribution protection controller, so as to wake up the power distribution protection controller in a standby state ready to respond at any time. In addition, the low-voltage ON power on the third circuit can also provide low-voltage ON power to the low-voltage electrical appliances and low-voltage related controllers through the fourth branch after passing through the vehicle ON power relay.

[0029] Furthermore, the first circuit in this embodiment can provide initial constant power for the power distribution protection controller when the main switch is closed to power on the power distribution protection controller and make it in a standby state ready to be awakened at any time. The second circuit can directly connect the low-voltage power supply and the power distribution protection controller when the main switch is disconnected, so as to provide extended constant power for the power distribution protection controller. Specifically for the second circuit, the low-voltage power supply in this embodiment can be directly connected to port C of the power distribution cabinet through the second circuit without passing through the main switch and firmly fixed (in this embodiment, fast plugs that are prone to looseness are not used, but more firm forms such as gland heads or bolt fixing are adopted). Inside port C of the power distribution cabinet, it is connected to the H port of the power distribution protection controller directly after passing through the contacts of the low-voltage power supply interlock relay, so as to provide extended constant power for the power distribution protection controller. The power distribution protection controller can use the extended constant power to perform delay control on the high-voltage contactor of the high-voltage electrical appliance to avoid load-breaking disconnection.

[0030] Specifically, this embodiment can protect the vehicle through the delay control of the power distribution protection controller when the main switch is disconnected. The power distribution cabinet outputs the control signal of the low-voltage interlock constant-power relay coil through the F port of the power distribution protection controller to control the closing or opening of the coil of the low-voltage interlock constant-power relay. When the contacts of the low-voltage interlock constant-power relay coil are closed, the first branch can output the extended constant power on the second circuit through the anti-cross-current diode 1 through the A port of the power distribution cabinet to the outside, and provide it to the high-voltage related controllers such as the vehicle control unit VCU or the battery management system BMS as a dedicated constant power with the function of delay protection. Moreover, the first branch is also connected to the first circuit through the anti-cross-current diode 3, so as to provide delayed protection constant power for the J port of the power distribution protection controller when the main switch is disconnected. Similarly, the power distribution cabinet outputs the control signal of the low-voltage interlock ON-power relay coil through the G port of the power distribution protection controller to control the closing or opening of the coil of the low-voltage interlock ON-power relay. When the contacts of the low-voltage interlock ON-power relay are closed, the second branch outputs the ON-power delayed power shunted from the second circuit through the anti-cross-current diode 2 through the B port of the power distribution cabinet to the outside, and provides it to the high-voltage related controllers such as the vehicle control unit VCU or the battery management system BMS as the wake-up ON power with the function of delay protection. An interlock is formed between the low-voltage interlock constant-power relay and the low-voltage interlock ON-power relay in this embodiment. For example, when the low-voltage interlock constant-power relay is closed, the low-voltage interlock ON-power relay is closed, so that the dedicated constant power and the wake-up ON power can be supplied to the high-voltage related controllers at the same time to ensure the delayed operation of the high-voltage related controllers. In addition, the second branch is also connected to the third circuit through the anti-cross-current diode 4 to provide delayed wake-up ON power for the wake-up interface K port of the power distribution protection controller when the main switch is disconnected.

[0031] In addition, the high-voltage power distribution protection system in this embodiment further includes a power replenishment controller, which can be integrated into the power distribution protection controller function or exist independently outside the power distribution cabinet. The power replenishment controller includes a first interface, a second interface, and a third interface. Specifically, the first interface (R port) of the power replenishment controller is connected to the first circuit upstream of the low-voltage power interlock relay to detect the battery direct connection voltage of the low-voltage power supply; the second interface (Q port) of the power replenishment controller is connected to the vehicle control unit VCU and the battery management system BMS, and is used to make the vehicle control unit VCU and the battery management system BMS enter the power replenishment mode when the battery direct connection voltage is lower than a preset threshold; the third interface (S port) of the power replenishment controller is connected in parallel to the DCDC converter and the power distribution protection controller, and is used to give a DC operation enable (DC operation enable means activating the DCDC converter through a control signal to make it perform the power conversion between high voltage and low voltage) and make the power distribution protection controller enter the power replenishment mode when the battery direct connection voltage is lower than a preset threshold. In this embodiment, the detection pin R of the power replenishment controller power supply is directly connected to the positive pole of the low-voltage power supply without passing through the main switch control, so as to prevent the power replenishment function from being turned off. The power replenishment controller can also output a power replenishment signal to the N pin of the power distribution protection controller through the S port. After receiving the power replenishment signal, the N pin of the power distribution protection controller enters the power replenishment mode. The power replenishment controller can also wake up the vehicle control unit VCU and the battery management system BMS through the Q port, so that the vehicle control unit VCU and the battery management system BMS enter the power replenishment mode, and at the same time close the high-voltage contactor required for the operation of the DCDC converter and give a DC operation enable (or the power distribution protection controller gives a DC operation enable in the power replenishment mode) to perform the power conversion between high voltage and low voltage.

[0032] The power distribution protection system in this embodiment has a status indication function. The power distribution protection system further includes a low-voltage status indicator light, a high-voltage status indicator light, a power replenishment status indicator light, and a power replenishment indicating buzzer for indication. Specifically, the low-voltage status indicator light, the high-voltage status indicator light, and the power replenishment status indicator light are respectively connected to the U port, V port, and W port of the power distribution protection controller. The low-voltage status indicator light is configured to flash when the main switch is closed, indicating that the power distribution protection controller has been powered on and is in the standby state; the low-voltage status indicator light is configured to be always on when the main switch, the low-voltage power interlock relay, the low-voltage interlock constant power relay, and the low-voltage interlock ON power relay are all closed, indicating that the power distribution protection controller outputs a dedicated constant power (the low-voltage interlock constant power relay is closed, and the first branch outputs a dedicated constant power to the VCU / BMS) and a wake-up ON power (the low-voltage interlock ON power relay is closed, and the second branch outputs a wake-up ON power to the VCU / BMS) and is in the power protection state.

[0033] The high-voltage status indicator light is configured to be always on when the vehicle has been ignited and started and the positive and negative contactors of any high-voltage circuit of the whole vehicle are closed, indicating that the power distribution protection controller is in the high-voltage protection state; when the power distribution protection controller is in the high-voltage protection state, the power distribution protection controller can maintain power-on by using the initial constant power provided by the first circuit, the directly connected extended constant power provided by the second circuit, or the protection constant power provided by the first branch connecting the first circuit. The power distribution protection controller can also provide dedicated constant power and wake-up ON power for the high-voltage related controllers through the first branch and the second branch respectively, and perform delay control on the high-voltage contactor corresponding to the high-voltage electrical appliance according to the delay requirement of the high-voltage electrical appliance through the high-voltage control interface. The shutdown sequence after the delay control ends is the low-voltage interlock ON power relay, the low-voltage interlock constant power relay, and the low-voltage power supply interlock relay. The charging status indicator light is configured to be always on when the vehicle is in the charging mode and the positive and negative contactors of any high-voltage circuit are closed. If the vehicle is also in the non-ignition state at the same time, the charging status indicator light flashes.

[0034] Specifically, since the instrument has been turned off when the key is in the off state, the driver may have also got out of the vehicle and turned off the main switch, or even left or started vehicle maintenance work. At this time, there is no indication or marker for high-voltage power-on to inform the driver of the working state of the current high-voltage circuit, whether the high voltage has been disconnected or is actually in the high-voltage state. However, the high voltage will continue to exist for a long time due to the needs of some vehicle system functions or be re-powered due to charging requirements. At this time, the power-on status indication function of the high-voltage power distribution system is required to ensure safety and clarify the working state. In this embodiment, the power distribution protection controller outputs multiple indication signals to the corresponding status indicator lights for lighting. The indicator lights can include different symbols and text markings to distinguish functions and states, and can provide corresponding signal flashing frequencies and different indicator light color changes, and even different regular beeps of the buzzer as different state differentiating indications.

[0035] Specifically, the low-voltage status indicator is connected to the U interface of the power distribution protection controller of the power distribution cabinet. When the green indicator flashes, it indicates that the power distribution cabinet and its internal power distribution protection controller have been powered on but not externally output. When the light is constantly on, it indicates that the dedicated normal power and wake-up ON power have been externally output to the high-voltage related controllers and entered the power protection state. The high-voltage status indicator lights up when the positive and negative contactors of any high-voltage circuit are fully closed, enabling a vehicle system or the inside of the power distribution cabinet to be powered on at high voltage. The high-voltage status indicator can be a red indicator. The charging status indicator lights up when the vehicle is in the charging mode and the relevant high-voltage circuit is closed and has high voltage (an orange indicator can be selected). When the light flashes, it represents that the vehicle is in the charging state with high voltage in the non-ignition state (such as when the main switch is not closed), and the flashing is used to strengthen the warning. When the light is constantly on, it represents that the vehicle is in the charging mode when powered on with low voltage (such as when the ignition lock is in the ACC or ON power state). When charging is performed when the vehicle is in the charging state and the main switch is not closed, it is easy for maintenance personnel to misjudge it as a power-off safety state, resulting in mental paralysis. Or charging can also be carried out in the ACC and ON power states. At this time, the charging indication buzzer sounds at a certain frequency, which can play a warning reminder role for charging to high voltage, avoiding safety accidents and also playing a role in status indication.

[0036] The working principle of the power distribution protection system of this embodiment is further described. The power distribution protection system includes a power-off state, a standby state, a charging state, and a high-voltage state.

[0037] Power-off state: When the vehicle is not powered on, the main switch is not turned on, and the ignition lock is not powered on, the HJK pins of the power distribution protection controller have no power, and the power distribution protection controller is in the power-off state.

[0038] Standby state: When the main switch is closed, the key power supply, the J pin of the power distribution protection controller, the ordinary low-voltage electrical appliances, and the low-voltage related controllers all obtain normal power. At this time, the power distribution protection controller is in the standby state and can respond at any time to be woken up. It controls the closing of the low-voltage interlock normal power relay through the F pin and outputs the wake-up ON power from the A pin of the power distribution cabinet to high-voltage related controllers such as the VCU and BMS, making them in the standby state.

[0039] Battery charging status: When there is a need for battery charging during the normal power standby state, the R pin of the charging controller detects the battery direct connection voltage of the low-voltage power supply entering from the C port of the power distribution cabinet and monitors it in real time. When the detected battery direct connection voltage is lower than the charging start voltage, the charging controller outputs a charging signal to start the charging mode of the power distribution protection controller through the N pin (as a mode input signal, the charging controller's S pin supplies power to the K pin of the power distribution protection controller to wake up the power distribution protection controller), closes the normally-closed relay for low-voltage interlock and the ON relay for low-voltage interlock to provide dedicated normal power and wake-up ON power to the high-voltage related controllers. The Q pin of the charging controller outputs a charging enable signal to the vehicle control unit VCU and the battery management system BMS through the P port of the power distribution cabinet. After the vehicle control unit VCU and the battery management system BMS drive the high-voltage contactors (or high-voltage relays) related to charging to close, the power distribution protection controller monitors the closing state of the high-voltage contactors of the high-voltage electrical appliances and sends relevant relay closing state messages to the vehicle control unit VCU and the battery management system BMS. The S pin of the charging controller wakes up the DCDC converter inside the power distribution cabinet through the T port (the diode 7 between the S pin of the charging controller and the T port of the DCDC converter is used to prevent reverse series power), and provides DCDC working enable to achieve the energy replenishment function. After the energy replenishment function of the vehicle control unit VCU ends, the S pin and Q pin of the charging controller stop outputting the wake-up signal and enable signal for the charging mode. The power distribution protection controller exits the charging mode and enters the original mode state. If the main switch is not closed, the DC working enable and the DCDC converter are terminated in sequence. After detecting that the output current drops to the safety threshold, the high-voltage positive-related power supply contactor and the high-voltage negative contactor of the DCDC converter are disconnected in sequence, and then the ON relay for low-voltage interlock and the normally-closed relay for low-voltage interlock are disconnected to return to the initial state, that is, if the main switch is not turned on, it is in the power-off shutdown state, and if the main switch is already turned on, it is in the standby state.

[0040] When the vehicle has been ignited and started, and any high-voltage circuit is completely closed to apply high voltage, it indicates that the power distribution cabinet has entered the high-voltage state. This is the state that requires the most high-voltage protection, and it is necessary to avoid the arc generated by disconnecting the contactor under load, subsequent adhesion, and the back electromotive force electrical impact of the equipment. When the power distribution cabinet enters the high-voltage state, the power distribution protection controller monitors the circuits of the positive and negative contactors that have been completely closed in real time. When the enable command to disconnect the high-voltage circuit is received, and the output current has been turned off or reduced below the permitted range value, the command to first disconnect the positive high-voltage contactor and then disconnect the negative contactor in sequence is permitted to be executed. After all high-voltage contactors are disconnected and the data retention delay time of each relevant controller in the circuit is reached, depending on the gear position of the key and the on / off state of the low-voltage power supply main switch, the low-voltage interlock ON relay, the low-voltage interlock constant-power relay are disconnected in sequence, and finally the low-voltage power supply interlock relay is disconnected. This operation method can ensure that when the equipment, communication, and lines are all normal and the low-voltage power supply main switch is directly turned off alone, it will not cause drawbacks such as adhesion and impact caused by the direct disconnection of the high-voltage relay-related circuits, and can perform the corresponding-stage delay and correct power-down process according to the control strategy, realizing the on-demand delay power-down in the normal way and the protective step-by-step delay power-down in abnormal situations, and can avoid all abnormal risks related to signals and controls brought by all external cables, power supplies, communications, control signals, and logics. In addition, when any status such as the enable message or signal, current determination limit value, positive and negative sequence of disconnecting the contactor, control command for disconnecting the contactor, messages and commands of relevant controllers such as VCU or BMS does not conform to the time sequence or protection strategy, it will not execute according to the abnormal command, but send a CAN alarm message. When the vehicle speed is 0, a protective power-down process is performed, waiting for the end of the delay working duration of the corresponding circuit and enabling it to be turned off in sequence, the output current of the corresponding circuit to drop below the specified limit value, the high voltage of the corresponding circuit to be disconnected or the active discharge delay time to be reached, then disconnect the high-voltage positive relay of the corresponding circuit, and after all the positive relays of all circuits are closed, disconnect the total negative relay (for circuits with independent high-voltage negative relays, the negative relay can be disconnected after the positive relay is disconnected).

[0041] The power distribution cabinet in this embodiment includes a power distribution protection controller. First, through the second circuit, the low-voltage power supply and the power distribution protection controller can be directly connected to perform delay control after the main switch is turned off and the vehicle is turned off. Moreover, the first branch and the second branch are respectively connected to the second circuit and the third circuit, which can provide the power distribution protection controller with protected constant power and protected ON power with a delay protection function. When the main switch is turned off, the power distribution cabinet can still supply power by itself at low voltage and has an interlock holding function. And the power distribution cabinet has logical control ability. Based on the power-on maintained by the second circuit, the first branch, and the second branch, it has a high-voltage component delay holding function, can perform delay control on the high-voltage contactor according to the delay requirements of high-voltage electrical appliances, and can still safely cut off the power under abnormal conditions, so as to softly land various risk faults. Furthermore, the power distribution cabinet in this embodiment has the ability to stably supply power to external controllers. The high-voltage related controllers and the components and systems that require delay are not affected by the accidental shutdown of the main switch by the driver. It also allows the driver to safely turn off the key and the main switch in a timely manner without having to wait for a long time. On the basis of the power distribution protection controller having the ability of delayed power supply, it can also ensure the reasonable delayed power-off of the controlled high-voltage electrical appliances, making the power distribution system and the vehicle operation more user-friendly. And the power distribution cabinet in this embodiment is perfectly integrated with the low-voltage charging ability without affecting the charging function. The visual indication function of each state of the power distribution cabinet plays a safety warning role, avoiding the risk of accidental electric shock, and can also avoid technical fault risks caused by external cable contact problems and electromagnetic interference. Through multiple anti-crossing diodes, it can also prevent the mutual crossing of each line. Embodiment 2

[0042] Based on the same inventive concept as in Embodiment 1, this embodiment provides a power distribution cabinet, including the power distribution protection system described in Embodiment 1. Embodiment 3

[0043] Based on the same inventive concept as in Embodiment 1, this embodiment provides a vehicle, including the power distribution protection system described in Embodiment 1.

[0044] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can still be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A high-voltage power distribution protection system, characterized in that, Including: A first circuit, which is connected from a low-voltage power supply through a main switch to the initial constant-power interface of a distribution protection controller, and the high-voltage control port of the distribution protection controller is connected to the high-voltage contactor of a high-voltage electrical appliance; A second circuit, which is connected from a low-voltage power supply through the contacts of a low-voltage power supply interlock relay to the delayed constant-power interface of the distribution protection controller; A third circuit, which is connected from a low-voltage power supply through the main switch and the contacts of a vehicle ON power relay to the wake-up interface of the distribution protection controller, and the first circuit, the second circuit and the third circuit are connected in parallel with each other; A first branch, where the second circuit downstream of the low-voltage power supply interlock relay is connected to a high-voltage related controller through the contacts of a low-voltage interlock constant-power relay; the first branch downstream of the low-voltage interlock constant-power relay is also connected to the first circuit downstream of the main switch; A second branch, which is connected in parallel with the first branch, and the second branch is connected from the second circuit downstream of the low-voltage power supply interlock relay through the contacts of a low-voltage interlock ON power relay to a high-voltage related controller; low- The second branch downstream of the voltage interlock ON power relay is connected to the third circuit downstream of the low-voltage interlock ON power relay; The low-voltage power supply interlock relay, the low-voltage interlock constant-power relay and the low-voltage interlock ON power relay are respectively connected to the corresponding control interfaces on the distribution protection controller, and the vehicle ON power relay is controlled by the ignition lock ON power.

2. The high-voltage power distribution protection system according to claim 1, wherein It also includes: A third branch, where the first circuit downstream of the main switch is connected to a low-voltage electrical appliance.

3. The high-voltage power distribution protection system according to claim 1, characterized in that It also includes: A fourth branch, where the third circuit downstream of the vehicle ON power relay is connected to a low-voltage electrical appliance and a low-voltage related controller.

4. The high-voltage power distribution protection system according to claim 1, characterized in that, It also includes: A low-voltage status indicator light, which is connected to the distribution protection controller; The low-voltage status indicator light is configured to flash when the main switch is closed, indicating that the distribution protection controller has been powered on and is in the standby state; The low-voltage status indicator light is also configured to be constantly on when the main switch, the low-voltage power supply interlock relay, the low-voltage interlock constant-power relay and the low-voltage interlock ON power relay are all closed, indicating that the distribution protection controller outputs dedicated constant power and wake-up ON power to the high-voltage related controller and is in the power protection state.

5. The high-voltage power distribution protection system according to claim 1, characterized in that, It also includes: A high-voltage status indicator light, which is connected to the distribution protection controller; The high-voltage status indicator light is configured to be constantly on when the vehicle has been ignited and started and the positive and negative contactors of any high-voltage circuit of the vehicle are closed, indicating that the distribution protection controller is in the high-voltage protection state; When the distribution protection controller is in the high-voltage protection state, it can maintain power on by using the conventional constant power provided by the first circuit, the delayed constant power provided by the second circuit or the protection constant power provided by connecting the first circuit through the first branch. The distribution protection controller can also provide dedicated constant power and wake-up ON power for the high-voltage related controller through the first branch and the second branch respectively, and perform delayed control on the high-voltage contactor corresponding to the high-voltage electrical appliance according to the delay requirement of the high-voltage electrical appliance through the high-voltage control port. The closing sequence after the delayed control ends is the low-voltage interlock ON power relay, the low-voltage interlock constant-power relay and the low-voltage power supply interlock relay.

6. The high-voltage power distribution protection system according to claim 1, characterized in that, The high-voltage related controller includes a vehicle controller VCU and a battery management system BMS.

7. The high-voltage power distribution protection system according to claim 6, characterized in that, It also includes: The charging compensation controller includes a first interface, a second interface, and a third interface; The first interface is connected to a first circuit upstream of the low-voltage power supply interlock relay to detect the direct battery voltage; The second interface is connected to the vehicle control unit VCU and the battery management system BMS, and is used to enable the vehicle control unit VCU and the battery management system BMS to enter the charging compensation mode when the direct battery voltage is lower than a preset threshold; The third interface is connected in parallel to the DCDC converter and the power distribution protection controller, and is used to give the DC operation enable and enable the power distribution protection controller to enter the charging compensation mode when the direct battery voltage is lower than a preset threshold.

8. The high-voltage power distribution protection system according to claim 7, characterized in that It further includes: A charging compensation status indicator light, connected to the power distribution protection controller; The charging compensation status indicator light is configured to be constantly on when the vehicle is in the charging compensation mode and the positive and negative contactors of any high-voltage circuit are closed. If the vehicle is also in the non-ignition state at the same time, the charging compensation status indicator light blinks.

9. A power distribution cabinet, characterized in that, It includes the high-voltage power distribution protection system according to any one of claims 1-8.

10. A vehicle, characterized in that, It includes the high-voltage power distribution protection system according to any one of claims 1-8.

Images