High voltage software interlock system, compressor controller, and electric compressor

Abstract

The application relates to the technical field of control circuits, and discloses a high-voltage software interlocking system, a compressor controller and an electric compressor, which comprise a high-voltage interlocking terminal J703, a bidirectional TVS diode TVS701, a triode Q701, a base bias resistor R702, a high-speed switch double diode D701, a pull-up resistor R701, a power filter capacitor C701, a pull-down resistor R704, a current-limiting resistor R703 and a signal filter capacitor C702. According to the application, the bidirectional TVS diode can inhibit differential mode peak voltage, the high-speed switch double diode can block single-end reverse voltage impact, the damage risk of elements such as the triode and the single-chip microcomputer can be reduced, and the hardware reliability can be improved; the pull-up resistor and the pull-down resistor form complementary bias, cooperate with the power filter capacitor and the signal filter capacitor to filter out signal jitter, ensure accurate output of a logic level, interact with a vehicle controller in real time to interlock a state, and form a closed-loop protection of hardware detection and system response.

Description

Technical Field

[0001] This application relates to the field of control circuit technology, and in particular to a high-voltage software interlock system, a compressor controller, and an electric compressor. Background Technology

[0002] In the thermal management system of new energy vehicles, the electric compressor is a core component, and the reliability of its high-voltage power supply circuit directly affects the safety of the entire vehicle. In the thermal management system of new energy vehicles, the high-voltage interlock signal of the electric compressor is the core trigger condition for the vehicle's high-voltage safety strategy—once the vehicle controller detects a high-voltage interlock fault, it will immediately execute forced strategies such as "lowering high voltage, prohibiting restarting and raising high voltage, and prohibiting charging," directly leading to:

[0003] Driving interruption: The vehicle suddenly loses power and breaks down while in motion, endangering the safety of the driver and passengers;

[0004] Power replenishment failure: The charging process is forcibly terminated and power replenishment is not possible.

[0005] Degraded availability: Manual intervention is still required to restart the system after a fault is recovered, resulting in a very poor user experience.

[0006] Therefore, there is an urgent need for a technology to implement a high-voltage safety strategy for the entire vehicle. Utility Model Content

[0007] The purpose of this application is to provide a high-voltage software interlock system for controlling electric compressors, so as to solve the technical problems mentioned in the background art.

[0008] To achieve the above objectives, this application discloses the following technical solutions:

[0009] In a first aspect, this application discloses a high-voltage software interlock system for controlling an electric compressor, comprising:

[0010] The high-voltage interlock terminal J703 has an ILB_J line led out from pin 1 and an ILA_J line led out from pin 2, and the ILA_J line is grounded.

[0011] A bidirectional TVS diode, TVS701, is connected across the ILB_J line and the ILA_J line;

[0012] The emitter of transistor Q701 is connected to a +3.3V power supply;

[0013] The base bias resistor R702 has its first end connected to the base of the transistor Q701;

[0014] The high-speed switching dual diode D701 has its anode connected to the ILB_J line and its cathode connected to the second end of the base bias resistor R702.

[0015] The pull-up resistor R701 has its first end connected to a +3.3V power supply and its second end connected to the base of the transistor Q701.

[0016] The power supply filter capacitor C701 is connected in parallel across the pull-up resistor R701;

[0017] The pull-down resistor R704 has its first end connected to the collector of the transistor Q701, and its second end grounded.

[0018] The current-limiting resistor R703 has its first end connected to the collector of the transistor Q701, and its second end connected to the I / O port of the microcontroller control chip, which is connected to the vehicle controller via a CAN network.

[0019] The first terminal of the signal filtering capacitor C702 is connected to the second terminal of the current limiting resistor R703, and the second terminal is grounded.

[0020] Preferably, the control chip is an MCU or a DSP chip.

[0021] Secondly, this application discloses a compressor controller, including the high-pressure software interlock system described above.

[0022] Secondly, this application discloses an electric compressor, including the compressor controller described above.

[0023] Beneficial effects: The high-voltage software interlock system for electric compressor control in this application uses a bidirectional TVS diode (TVS701) connected across the ILB_J and ILA_J lines to suppress differential-mode voltage spikes; a high-speed switching dual diode (D701) connected in series with the ILB_J line blocks single-ended reverse voltage surges. The bidirectional TVS diode (TVS701) and the high-speed switching dual diode (D701) provide dual protection against both differential and single-ended voltage spikes, reducing the risk of damage to components such as the transistor (Q701) and the microcontroller, thus improving hardware reliability. Secondly, the pull-up resistor (R701) and pull-down resistor (R704) form complementary biases, working in conjunction with the power supply filter capacitor (C701) and signal filter capacitor (C702) to filter signal jitter, ensuring accurate output of the +3.3V logic level and avoiding misjudgments of the interlock state due to interference. Furthermore, the microcontroller interacts with the vehicle controller in real-time via the CAN network to monitor the interlock state. In case of a fault, the vehicle can quickly execute strategies such as high-voltage power-off, fault alarm, and power restriction, forming a closed-loop protection system of hardware detection and system response, enhancing the safety redundancy of the high-voltage system. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 The hardware circuit schematic diagram of a high-voltage software interlock system for controlling an electric compressor is provided in the embodiments of this application.

[0026] Figure 2 A schematic diagram of the software architecture of a high-voltage software interlock system for controlling an electric compressor, provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] In this document, the term "comprising" is intended to cover a 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 a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0029] This embodiment provides a high-voltage software interlock system for controlling an electric compressor, comprising hardware sensing and software decision-making. At the hardware sensing level, such as... Figure 1 The hardware circuit diagram shown corresponds to the high-voltage software interlock system for controlling an electric compressor, including high-voltage interlock terminal J703, bidirectional TVS diode TVS701, transistor Q701, base bias resistor R702, high-speed switching dual diode D701, pull-up resistor R701, power supply filter capacitor C701, pull-down resistor R704, current limiting resistor R703, and signal filter capacitor C702.

[0030] The following is a detailed introduction to each component of the hardware circuit.

[0031] High voltage interlock terminal J703

[0032] Model: FWF20029-S-2B25NAMTXGA, Package: PH2.0-2P-H (2-pin through-hole structure).

[0033] Connection logic: Pin 1 leads out the ILB_J line (interlock detection signal line), and pin 2 leads out the ILA_J line (directly grounded, serving as the reference ground for the interlock circuit). By inserting a short circuit / not inserting an open circuit physical state, the electrical signal change is triggered.

[0034] bidirectional TVS diode TVS701

[0035] Model: PESD2CAN,215_AU (Bidirectional transient suppression diode), Package: SOT-23-3 (Surface mount, 3-pin symmetrical structure).

[0036] Function: Connected between ILB_J and ILA_J lines, it suppresses differential mode voltage spikes (such as pulses generated by electromagnetic interference in high-voltage systems), clamps the voltage across the two ends within a safe range, and protects subsequent circuits (such as transistor Q701 and microcontrollers).

[0037] High-speed switching dual diode D701

[0038] Model: BAV99WTQ-F2-0000HF (High-speed switching dual diodes, only one is used in this circuit), Package: SOT323 (Ultra-small surface mount, saving space).

[0039] Connection logic: The anode is connected to the ILB_J line (the line segment between the bidirectional TVS diode TVS701 and the base bias resistor R702), and the cathode is connected to the input terminal of the base bias resistor R702 (i.e., the second terminal of R702). The unidirectional conductivity is used to block the reverse voltage surge (such as a negative surge pulse) on the ILB_J line side, so as to avoid damage to the base of the transistor Q701 due to reverse voltage.

[0040] Pull-up resistor R701

[0041] Model 4K7F_AU, resistance 4.7KΩ, accuracy ±1% (F grade, to ensure batch consistency), package 0402.

[0042] Connection logic: The first terminal is connected to a +3.3V power supply, and the second terminal is connected to the collector of transistor Q701, forming a bias path from the collector to the power supply to provide drive for high-level output.

[0043] Base bias resistor R702

[0044] Model 1KF_AU, resistance 1KΩ, accuracy ±1%, package 0402.

[0045] Connection logic: The second terminal is connected to the cathode of the high-speed switching dual diode D701, and the first terminal is connected to the base of the transistor Q701. Together with the pull-up resistor R701, they form a voltage divider circuit to control the base bias current.

[0046] Current limiting resistor R703

[0047] Model 1KF_AU, resistance 1KΩ, accuracy ±1%, package 0402.

[0048] Connection logic: The first terminal is connected to the emitter of transistor Q701, and the second terminal is connected to the I / O port of the microcontroller control chip to limit the emitter current and buffer signal fluctuations. The control chip is either an MCU or a DSP chip. When the control chip is an MCU, the second terminal of the current-limiting resistor R703 is connected to the IL_MCU terminal of the MCU.

[0049] Pull-down resistor R704

[0050] Model number 4K7F_AU, resistance 4.7KΩ, accuracy ±1%, package 0402.

[0051] Connection: Connect the first terminal to the emitter of transistor Q701, and ground the second terminal to stabilize the emitter potential and ensure that the low-level output is close to 0V.

[0052] Transistor Q701

[0053] Model: MMST3906Q-F2-0000HF_AU (PNP type high frequency switching transistor), package: SOT323.

[0054] Function: As a core switching element, it controls the conduction / cutoff of the collector-emitter junction through changes in the base potential (high / low), thereby achieving the conversion between interlocked states and logic levels.

[0055] When the high-voltage interlock terminal J703 is not inserted, the ILB_J line and the ILA_J line are disconnected. The base of transistor Q701 forms a bias path through the base bias resistor R702 and the pull-up resistor R701, causing the IL_MCU terminal to output a 0 level pulled down to ground. When the high-voltage interlock terminal J703 is inserted, the ILB_J line and the ILA_J line are short-circuited (the ILB_J line is grounded). The base potential of transistor Q701 is pulled low, causing the IL_MCU terminal to output a high level associated with +3.3V.

[0056] Power supply filter capacitor C701

[0057] Model 10nF / 50V_AU, capacity 10nF, withstand voltage 50V (far exceeding the 3.3V operating voltage, with sufficient safety redundancy), package 0402.

[0058] Connection logic: It is connected in parallel across the pull-up resistor R701 (between +3.3V and the collector of transistor Q701) to filter out high-frequency ripple at the power supply end (such as switching noise of the 3.3V power supply) and avoid interference with the base bias circuit.

[0059] Signal filter capacitor C702

[0060] Model 10nF / 50V_AU, capacity 10nF, withstand voltage 50V, package 0402.

[0061] Connection logic: The first terminal is connected to the second terminal of the current-limiting resistor R703, and the second terminal is grounded, that is, connected in parallel between the IL_MCU terminal and ground to filter out high-frequency noise at the signal terminal (such as electromagnetic interference from wire coupling) and ensure stable logic level.

[0062] The hardware circuit described above includes several test points. These test points serve to provide measurable electrical connections for circuit debugging, production testing, and troubleshooting. The specific test points are as follows:

[0063] Test point TP04 is set on the ILB_J line between the high voltage interlock terminal J703 and the bidirectional TVS diode TVS701. Test point TP05 is set on the ILB_J line between the high voltage interlock terminal J703 and the bidirectional TVS diode TVS701. Test points TP04 and TP05 are used to monitor the original signal of the interlock line and determine whether the wire harness and terminals are normal.

[0064] A test point TP06 is set between the cathode of the high-speed switching dual diode D701 and the second end of the base bias resistor R702, and a test point TP07 is set between the first end of the base bias resistor R702 and the base of the transistor Q701. Test points TP06 and TP07 are used to monitor the diode output and base bias to determine whether the surge protection and transistor drive are normal.

[0065] The second end of the current-limiting resistor R703 is equipped with a test point TP08. The test point TP08 is used to monitor the logic level of the microcontroller control chip and verify whether the signal conversion is correct.

[0066] In addition, such as Figure 2 The diagram shows the software architecture of the high-voltage software interlock system for controlling the electric compressor. The microcontroller control chip uses the IL_MCU level input from the above hardware circuit to determine the high-voltage interlock status at a rate of milliseconds and control the compressor status. It then sends the information to the vehicle via the CAN network, allowing the vehicle to receive the high-voltage interlock status of the electric compressor and control whether the vehicle's high-voltage battery supplies power to the electric compressor through the vehicle's logic.

[0067] Based on the above, the high-voltage software interlock system for electric compressor control in this embodiment constructs a safety protection network for the high-voltage system through a hardware-sensing and software-decision-making model. Its core value lies not only in rapid response to faults but also in preventative safety management through intelligent logic, making it a crucial element in the electrical safety design of new energy vehicles. As electric vehicle high-voltage platforms evolve towards 800V and above, the algorithm accuracy and real-time performance of software interlocks will face higher requirements, becoming an important dimension of technological competition among automakers.

[0068] In summary, the high-voltage software interlock system for electric compressor control in this embodiment uses a bidirectional TVS diode (TVS701) connected across the ILB_J and ILA_J lines to suppress differential-mode voltage spikes. A high-speed switching dual diode (D701) is connected in series with the ILB_J line to block single-ended reverse voltage surges. The bidirectional TVS diode (TVS701) and the high-speed switching dual diode (D701) provide dual protection against both differential and single-ended voltage spikes, reducing the risk of damage to components such as the transistor Q701 and the microcontroller, thus improving hardware reliability. Secondly, pull-up resistors R701 and R704 form complementary biases, working in conjunction with power supply filter capacitor C701 and signal filter capacitor C702 to filter signal jitter, ensuring accurate output of the +3.3V logic level and preventing misjudgments of the interlock state due to interference. Furthermore, the microcontroller interacts with the vehicle controller in real-time via the CAN network to monitor the interlock state. In case of a fault, the vehicle can quickly execute strategies such as high-voltage power-off, fault alarm, and power restriction, forming a closed-loop protection system of hardware detection and system response, enhancing the safety redundancy of the high-voltage system.

[0069] This embodiment provides a compressor controller in a second aspect, including the high-pressure software interlock system as described above. That is, the compressor controller is equipped with the high-pressure software interlock system and operates under the control of the high-pressure software interlock system.

[0070] In a second aspect, this embodiment provides an electric compressor, including a compressor controller as described above, that is, the electric compressor is connected to the compressor controller and operates under the control of the compressor controller.

[0071] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A high-voltage software interlock system, characterized in that, include: The high-voltage interlock terminal J703 has an ILB_J line led out from pin 1 and an ILA_J line led out from pin 2, and the ILA_J line is grounded. A bidirectional TVS diode, TVS701, is connected across the ILB_J line and the ILA_J line; The emitter of transistor Q701 is connected to a +3.3V power supply; The base bias resistor R702 has its first end connected to the base of the transistor Q701; The high-speed switching dual diode D701 has its anode connected to the ILB_J line and its cathode connected to the second end of the base bias resistor R702. The pull-up resistor R701 has its first end connected to a +3.3V power supply and its second end connected to the base of the transistor Q701. The power supply filter capacitor C701 is connected in parallel across the pull-up resistor R701; The pull-down resistor R704 has its first end connected to the collector of the transistor Q701, and its second end grounded. The current-limiting resistor R703 has its first end connected to the collector of the transistor Q701, and its second end connected to the I / O port of the microcontroller control chip, which is connected to the vehicle controller via a CAN network. The first terminal of the signal filtering capacitor C702 is connected to the second terminal of the current limiting resistor R703, and the second terminal is grounded.

2. The high-voltage software interlock system according to claim 1, characterized in that, The control chip is an MCU or a DSP chip.

3. A compressor controller, characterized in that, Including the high-voltage software interlock system as described in claim 1 or 2.

4. An electric compressor, characterized in that, Includes the compressor controller as described in claim 3.

Images