Relay bilateral control circuit with high reliability

Abstract

The utility model provides a high-reliability relay bilateral control circuit which comprises a microprocessor module, an AND gate, a high-side control module, a relay and a low-side control module which are connected in sequence, the low-side control module is further connected with the microprocessor module, and the AND gate is further connected with a power management module. According to the invention, when single-side control is abnormal, the relay is switched off through control on the other side, so that the personal safety is ensured. Besides, after an enable signal of the main control chip and a feedback signal of the power supply module pass through the AND gate, the high-side control module is allowed to be driven, and when any one is abnormal, enabling cannot be controlled, so that reliable control of the relay is effectively ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive electronic products, and particularly to a highly reliable relay bilateral control circuit. Background Art

[0002] For the vehicle controller of an electric vehicle, in terms of relay drive control, a high-side drive control scheme is usually used. This scheme is simple to operate, but there are problems of unstable independent drive and susceptibility to interference. Another scheme is bilateral control, but when there is an abnormal power supply, the level of the control signal is also abnormal, and the stability and reliability of the control are relatively low.

[0003] Currently, as the requirements of vehicle manufacturers for the control safety and reliability of the vehicle power system are getting higher and higher, the above methods gradually no longer meet the safety and reliability requirements of vehicle manufacturers. Summary of the Invention

[0004] To solve the above problems, the present invention discloses a highly reliable relay bilateral control circuit, which can enable the system to disconnect the relay through the control of the other side when the unilateral control is abnormal, ensuring personal safety. In addition, after the enable signal of the main control chip and the feedback signal of the power supply module pass through an AND gate, the high-side control module is allowed to be driven. If any one of them is abnormal, the control cannot be enabled, thereby effectively ensuring the reliable control of the relay.

[0005] The specific solution is as follows:

[0006] A highly reliable relay bilateral control circuit, characterized by comprising a microprocessor module, an AND gate, a high-side control module, a relay, and a low-side control module connected in sequence. The low-side control module is also connected to the microprocessor module, and the AND gate is also connected to a power management module. The microprocessor module is the control unit of the entire circuit, used to output control signals to control the high-side control module and the low-side control module, and can diagnose whether there is an abnormality in its control loop by collecting the outputs of the corresponding control modules. The AND gate is used to receive the valid signals of the microprocessor module and the power management module, and will output a control signal to the high-side control module only when both received signals are high-level signals. The high-side control module is used to receive the control signal output by the microprocessor module to control the power-on and power-off of the high-side end of the relay coil. The low-side control module is used to receive the control signal output by the microprocessor module to control the power-on and power-off of the low-side end of the relay coil.

[0007] As a further improvement of the present invention, the power management module supplies power to the entire circuit and can monitor its own power supply and communication status. When there is an abnormality in the output voltage of each path or communication with the main control, it will send a low-state signal to the external control module to indicate that the power management module has an abnormality.

[0008] As a further improvement of the present invention, the high-side control module is built-in with an output current acquisition unit for real-time acquisition of the output current, and at the same time has protection and diagnosis for short-to-ground, short-to-power supply, and open circuit.

[0009] As a further improvement of the present invention, after the coil of the relay is controlled to close by the high-side control module and the low-side control module, it will be energized to generate a magnetic field, attracting the closing of the switch contact, thereby completing the closing of the switch of the power circuit and completing the power transmission between the battery pack and electrical equipment such as the motor.

[0010] The beneficial effects of the present invention are as follows:

[0011] 1. Dual redundant control of the relay. When the control of the high-side or low-side fails (for example, unable to control disconnection), the power supply to the relay coil can be cut off through the other side to cut off the power output and ensure personal safety.

[0012] 2. The enable signal of the relay coil and the status feedback signal of the power supply module control the high-side to close after passing through an AND gate, with higher control reliability. That is to say, when the system ensures normal power supply and communication of the power supply module and the processor correctly issues a control enable signal, the high-side of the coil will be energized and closed. At this time, when the low-side control module is closed, the relay will correctly close and work. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a circuit schematic diagram of the present invention.

[0014] LIST OF REFERENCE NUMERALS:

[0015] 101 - Power management module, 102 - Microprocessor module, 103 - AND gate, 104 - High-side control module, 105 - Low-side control module, 106 - Relay. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present invention will be further clarified below in conjunction with the drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and not to limit the scope of the present invention.

[0017] The present invention provides a highly reliable bilateral control circuit for a relay, which includes a microprocessor module 102, an AND gate 103, a high-side control module 104, a relay 106, and a low-side control module 105 connected in sequence. The low-side control module is also connected to the microprocessor module 102, and the AND gate is also connected to a power management module 101. The microprocessor module is the control unit of the entire circuit, which is used to output control signals to control the high-side control module and the low-side control module, and can diagnose whether there is an abnormality in its control loop by collecting the outputs of the corresponding control modules. The AND gate is used to receive valid signals from the microprocessor module and the power management module, and will output a control signal to the high-side control module only when both received signals are high-level signals. The high-side control module is used to receive the control signal output by the microprocessor module to control the power-on and power-off of the high-side end of the relay coil. The low-side control module is used to receive the control signal output by the microprocessor module to control the power-on and power-off of the low-side end of the relay coil.

[0018] In this embodiment, the power management module supplies power to the entire circuit and can monitor its own power supply and communication status. When there is an abnormality in the output voltage of each path or the communication with the main control, it will send a low-state signal to the external control module to indicate that the power management module has an abnormality.

[0019] In this embodiment, the high-side control module is built-in with an output current acquisition unit, which is used to collect the output current in real time and also has protection and diagnosis functions for short circuit to ground, short circuit to power supply, and open circuit.

[0020] In this embodiment, after the coil of the relay is controlled to close by the high-side control module and the low-side control module, it will be energized to generate a magnetic field, attracting the closing of the switch contact, thereby completing the closing of the power circuit switch and the power transmission between the battery pack and the motor electrical equipment.

[0021] As Figure 1 shown, when the vehicle needs to control the power system relay to close and drive the motor, the vehicle controller will send a signal to the microprocessor module of the present utility model. After receiving the command, the microprocessor will send an enable signal to the AND gate. Only when the power module works normally (that is, the power supply to the microprocessor IO port, AD sampling port, etc. is normal), the feedback pin signal will also send a high-level signal to the AND gate. At this time, the AND gate sends a high-level signal to the high-side control module, and the high-side control closes normally. At this time, the microprocessor controls the low-side control module to close, then the relay power supply circuit is formed, the relay is energized and closed, and the system power supply is successful.

[0022] The feedback signal added to the power supply module ensures the normal power supply of modules such as the power supply of the IO port, the power supply for AD sampling, and the core power supply of the system, so as to ensure that the enable signal and the feedback diagnosis signal have high accuracy and reliability. When the power supply is abnormal, the status feedback signal of the power management module becomes low level, stops the enable signal of the high-side control module, and turns off the high-side power supply of the relay.

[0023] The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A high reliability relay bilateral control circuit, characterized in that: It comprises a microprocessor module, an AND gate, a high-side control module, a relay and a low-side control module which are connected in sequence, wherein the low-side control module is also connected to the microprocessor module, and the AND gate is also connected to a power management module; the microprocessor module is a control unit of the entire circuit, which is used to output a control signal, control the high-side control module and the low-side control module, and can diagnose whether there is an abnormality in its control loop by collecting the output of the corresponding control module; the AND gate is used to receive valid signals from the microprocessor module and the power management module, and will output a control signal to the high-side control module only when and only when two high-level signals are received; the high-side control module is used to receive the control signal output by the microprocessor module, so as to control the power-on and power-off of the high-side end of the relay coil; the low-side control module is used to receive the control signal output by the microprocessor module, so as to control the power-on and power-off of the low-side end of the relay coil.

2. A high reliability relay bilateral control circuit according to claim 1, characterized in that: The power management module supplies power to the entire circuit and can monitor its own power supply and communication status. When there is an abnormality in the output voltage of each channel or in the communication with the main control, a low status signal will be sent to the external control module to indicate that an abnormality has occurred in the power management module.

3. A high reliability relay bilateral control circuit according to claim 1, characterized in that: The high-side control module has a built-in output current acquisition unit for real-time output current acquisition, and has short-to-ground, short-to-power and open-circuit protection and diagnosis.

4. A high reliability relay bilateral control circuit according to claim 1, characterized in that: The coil of the relay will be energized after the high-side control module and the low-side control module are controlled to close, generating a magnetic field to attract the closure of the switch contacts, thereby completing the closure of the power circuit switch and completing the power transmission between the battery pack and the motor electrical equipment.

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