Reverse connection protection circuit and vehicle-mounted refrigerator compressor controller

Abstract

The utility model discloses a reverse connection protection circuit and a vehicle-mounted refrigerator compressor controller, the reverse connection protection circuit is used in the vehicle-mounted refrigerator compressor controller, and the reverse connection protection circuit comprises an MOS tube, a divider resistor and a voltage stabilizing diode. The drain electrode of the MOS tube is connected with the negative electrode of the external input circuit, and the source electrode of the MOS tube is connected with the negative electrode output end of the external input circuit. One end of the divider resistor is connected with the positive electrode of an external input circuit, the other end of the divider resistor is connected with the negative electrode of a voltage stabilizing diode, and the other end of the divider resistor is also connected with the grid electrode of the MOS tube. The positive electrode of the voltage stabilizing diode is connected with the source electrode of the MOS tube, and the negative electrode of the voltage stabilizing diode is also connected with the grid electrode of the MOS tube; wherein the grid electrode of the MOS tube is also connected with a main control chip, and the main control chip is used for controlling a post-stage circuit to stop.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle refrigerator compressor controller circuits, in particular to a reverse connection protection circuit and a vehicle refrigerator compressor controller. Background Art

[0002] Car refrigerators are the continuation of home refrigerators. There are two main types of car refrigerators on the market. One is a semiconductor car refrigerator, which uses semiconductor electronic refrigeration technology; the other is a compressor car refrigerator, where the compressor is a traditional technology of traditional refrigerators. The refrigeration temperature of the compressor car refrigerator is low, ranging from -18 degrees to 10 degrees, and the refrigeration efficiency is high, which can make ice and keep fresh. In the circuit control system of the car refrigerator, the compressor controller is the key component of the car refrigerator system, and the safety and reliability of the controller are very important.

[0003] At present, car refrigerators are powered by the car power supply. For car battery power supply, there are generally protection measures. The reverse protection circuit does not have much effect on the car power supply, but it will damage the electronic control board of the car refrigerator, so the role of the reverse protection circuit in the compressor controller is very important.

[0004] However, the applicant has found through research that currently, car refrigerators in the industry generally use N-type MOSFET as a reverse connection protection element. The disadvantage of this reverse connection protection circuit is that if the MOSFET is damaged, the subsequent circuit cannot sense it. If the subsequent circuit can continue to operate when the reverse connection protection MOSFET fails, it will cause the circuit board to have a high temperature and burn out. Utility Model Content

[0005] In order to overcome the above technical defects, the utility model provides a reverse connection protection circuit and a vehicle refrigerator compressor controller.

[0006] In order to solve the above problems, the utility model is implemented according to the following technical solutions:

[0007] In a first aspect, the utility model provides a reverse connection protection circuit, which is used in a vehicle refrigerator compressor controller, and is characterized in that the reverse connection protection circuit comprises:

[0008] A MOS tube, wherein the drain of the MOS tube is connected to the negative electrode of the external input circuit, and the source of the MOS tube is connected to the negative electrode output terminal of the external input circuit;

[0009] A voltage-dividing resistor, one end of which is connected to the positive electrode of the external input circuit, the other end of which is connected to the negative electrode of a voltage-stabilizing diode, and the other end of which is also connected to the gate of the MOS tube;

[0010] A voltage stabilizing diode, wherein the positive electrode of the voltage stabilizing diode is connected to the source electrode of the MOS tube, and the negative electrode of the voltage stabilizing diode is also connected to the gate electrode of the MOS tube;

[0011] The gate of the MOS tube is also connected to a main control chip, and the main control chip is used to control the subsequent circuit to stop.

[0012] In a second aspect, the utility model provides a vehicle refrigerator compressor controller, comprising a power supply circuit and a main control chip connected thereto;

[0013] The power supply circuit includes the reverse connection protection circuit described in the first aspect, and the main control chip is connected to the reverse connection protection circuit.

[0014] In combination with the second aspect, the utility model also provides a first specific implementation of the second aspect. Specifically, the vehicle refrigerator compressor controller includes:

[0015] Main control chip;

[0016] A power supply circuit, wherein the power supply circuit is connected to the main control chip;

[0017] A PWM buffer circuit, wherein the PWM buffer circuit is connected to the main control chip;

[0018] An IPM inverter drive circuit is connected to the PWM buffer circuit, and the IPM inverter drive circuit is connected to a vehicle-mounted compressor.

[0019] In combination with the second aspect, the utility model also provides a second specific implementation of the second aspect. Specifically, the vehicle refrigerator compressor controller includes:

[0020] An ADC sampling circuit is connected to the main control chip.

[0021] In combination with the second aspect, the utility model also provides a third specific implementation of the second aspect. Specifically, the vehicle refrigerator compressor controller includes:

[0022] A fault detection circuit is connected to the main control chip, and the fault detection circuit is connected to the IPM inverter drive circuit.

[0023] Compared with the prior art, the beneficial effects of the utility model are:

[0024] The utility model provides a reverse connection protection circuit, which is used in a vehicle refrigerator compressor controller. The reverse connection protection circuit includes a MOS tube, a voltage-dividing resistor and a voltage-stabilizing diode. The drain of the MOS tube is connected to the negative electrode of the external input circuit, and the source of the MOS tube is connected to the negative output terminal of the external input circuit. One end of the voltage-dividing resistor is connected to the positive electrode of the external input circuit, and the other end of the voltage-dividing resistor is connected to the negative electrode of a voltage-stabilizing diode, and the other end of the voltage-dividing resistor is also connected to the gate of the MOS tube. The positive electrode of the voltage-stabilizing diode is connected to the source of the MOS tube, and the negative electrode of the voltage-stabilizing diode is also connected to the gate of the MOS tube; wherein the gate of the MOS tube is also connected to a main control chip, and the main control chip is used to control the subsequent circuit to stop.

[0025] In the reverse connection protection circuit of this patent, the driving signal of the MOS tube is innovatively used as an enabling signal to determine whether the reverse connection protection circuit is normal. If the MOS tube fails, the MOS tube will show a short circuit between the driving gate and the drain, which will pull the driving signal of the MOS tube down to 0V. After the main control module recognizes it, it will turn off the power circuit / power module of the subsequent circuit or make the output voltage of the power circuit / power module 0, so that the subsequent circuit stops running. The MOS tube has a small current, generates little heat, and has a low temperature, which will not cause the PCB circuit board to burn out.

[0026] The anti-reverse connection circuit is composed of MOS tube, which has simple structure, low static power consumption and low cost. When the MOS tube fails, it can automatically identify and then shut down the power output of the subsequent circuit, so as to achieve the purpose of shutting down the subsequent circuit and stop the operation of the subsequent circuit, thus achieving the result of linkage protection and improving the reliability of the refrigeration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0028] Figure 1 It is a circuit topology diagram of the reverse connection protection circuit of the utility model;

[0029] Figure 2 It is a block diagram of a vehicle refrigerator compressor controller of the utility model;

[0030] Figure 3 It is a circuit topology diagram of the PWM buffer circuit of the utility model;

[0031] Figure 4 It is a circuit topology diagram of the IPM inverter drive circuit of the utility model;

[0032] Figure 5 It is a circuit topology diagram of the ADC sampling circuit of the utility model;

[0033] Figure 6 It is a circuit topology diagram of the fault detection circuit of the utility model;

[0034] In the figure:

[0035] 10- Main control chip;

[0036] 20-power circuit;

[0037] 30-PWM buffer circuit;

[0038] 40-IPM inverter drive circuit. DETAILED DESCRIPTION

[0039] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0040] like Figure 1 As shown, a preferred structure of a reverse connection protection circuit described in the utility model.

[0041] like Figure 1 As shown, the utility model provides a reverse connection protection circuit, which is used in a vehicle refrigerator compressor controller. The reverse connection protection circuit includes:

[0042] A MOS tube, wherein the drain of the MOS tube is connected to the negative electrode of the external input circuit, and the source of the MOS tube is connected to the negative electrode output terminal of the external input circuit;

[0043] A voltage-dividing resistor, one end of which is connected to the positive electrode of the external input circuit, the other end of which is connected to the negative electrode of a voltage-stabilizing diode, and the other end of which is also connected to the gate of the MOS tube;

[0044] A voltage stabilizing diode, wherein the positive electrode of the voltage stabilizing diode is connected to the source electrode of the MOS tube, and the negative electrode of the voltage stabilizing diode is also connected to the gate electrode of the MOS tube;

[0045] The gate of the MOS tube is also connected to a main control chip, and the main control chip is used to control the subsequent circuit to stop.

[0046] In the reverse connection protection circuit of this patent, the driving signal of the MOS tube is innovatively used as an enabling signal to determine whether the reverse connection protection circuit is normal. If the MOS tube fails, the MOS tube will show a short circuit between the driving gate and the drain, which will pull the driving signal of the MOS tube down to 0V. After the main control module recognizes it, it will turn off the power circuit / power module of the subsequent circuit or make the output voltage of the power circuit / power module 0, so that the subsequent circuit stops running. The MOS tube has a small current, generates little heat, and has a low temperature, which will not cause the PCB circuit board to burn out.

[0047] In view of the situation that there is no protection after the general reverse connection protection circuit fails, we have optimized and improved the circuit so that when the reverse connection protection MOS tube fails, the main control chip can identify and drive the shutdown of the subsequent circuit through the change of electrical signals, avoiding the failure caused by the continued operation of the subsequent circuit. The anti-reverse connection circuit using MOS tube has a simple structure, low static power consumption, and low cost. When the MOS tube fails, it can automatically identify and shut down the power output of the subsequent circuit, so as to achieve the purpose of shutting down the subsequent circuit, stop the operation of the subsequent circuit, achieve the result of linkage protection, and improve the reliability of the refrigeration equipment.

[0048] like Figure 2 As shown, the utility model also provides a preferred structure of a vehicle refrigerator compressor controller.

[0049] like Figure 2 As shown, the vehicle refrigerator compressor controller includes a main control chip, a power supply circuit, a PWM buffer circuit and an IPM inverter drive circuit. The power supply circuit is connected to the main control chip, the power supply circuit includes a reverse connection protection circuit, and the main control chip is connected to the reverse connection protection circuit.

[0050] In a specific implementation, the main control chip can adopt a 32-bit TMS28x series chip. The chip supports a processing frequency of 90MHz, supports floating-point unit operations, passes the automotive AECQ100 automotive-grade chip certification, and supports low-power operation mode.

[0051] Specifically, the power supply circuit is a conventional technical means in the art, and is set for vehicle refrigerator compressor controllers of different models and different electrical hardware. Therefore, the present application does not limit the specific circuit structure of the power supply circuit. The power supply circuit with the reverse connection protection circuit of this patent is based on the attached Figure 1 And the records of this patent specification can be easily realized and implemented by those skilled in the art.

[0052] For this product, the power supply circuit of the car refrigerator compressor controller mainly includes two parts: high-voltage power supply and low-voltage power supply. The high-voltage power supply mainly provides high-voltage input to the insulated gate bipolar transistor (IGBT) integrated inside the IPM, and the low-voltage power supply provides high-voltage input to the low-voltage circuit. The low-voltage power supply circuit can include 12V to 5V and 15V circuits, 5V to 3.3V circuits, 3.3V to 1.65V circuits, etc.

[0053] Specifically, the PWM buffer circuit is connected to the main control chip. Figure 3 As shown, it is a circuit topology diagram of the PWM buffer circuit.

[0054] Specifically, the pulse width modulation buffer circuit, as the front-stage circuit of the IPM inverter drive circuit, realizes the conversion from 3.3V signal level to 5V signal level. The three groups of PWM signals can be turned on or off at the same time through the common enable terminal G3. U13 is a 74HC245 bus transceiver. The core has 7 input and output ports at the same time. R100 is the pull-up resistor of the enable terminal G3, and the upper end of the resistor is connected to 3.3V. The U13 input port is connected to the digital ground through a pull-down resistor to ensure that the output signal is low level by default when powered on, protecting the IPM chip at the hardware level.

[0055] Specifically, the IPM inverter drive circuit is connected to the PWM buffer circuit, and the IPM inverter drive circuit is connected to the vehicle compressor. Figure 4 As shown, it is a circuit topology diagram of the IPM inverter drive circuit.

[0056] In a preferred embodiment, the vehicle refrigerator compressor controller includes:

[0057] ADC sampling circuit, the ADC sampling circuit is connected to the main control chip. The ADC sampling circuit mainly realizes the acquisition of the corresponding phase current signal and provides a feedback signal for the closed-loop control of the vehicle refrigerator compressor. The phase current sampling circuit adopts a differential operational amplifier circuit to amplify and transmit the acquired voltage signal. U1B is an operational amplifier with a 6MHz bandwidth, a typical offset voltage of 50uV, a typical open-loop gain of 105dB and a power input of 2.1V to 6V, which can realize accurate phase current sampling and distortion-free amplification. In a specific implementation, such as Figure 5 As shown, it is a circuit topology diagram of the ADC sampling circuit.

[0058] A fault detection circuit is connected to the main control chip, and the fault detection circuit is connected to the IPM inverter drive circuit.

[0059] In this patent, the fault detection circuit mainly detects the fault status of the IPM inverter drive module, and the fault status are IPM undervoltage fault, bus current overcurrent fault and IPM overtemperature fault, etc. U5 is a bus logic chip, R64 is a pull-up resistor for the fault input port, and the fault level is input from the logic port U5A and output from U5B in turn. The output fault level will maintain the same phase as the input fault level. R62 is a current limiting resistor, and D10 is a low-power light-emitting diode. D10 and R62 are connected in series to play a light-emitting alarm role.

[0060] In a specific implementation, Figure 6 As shown, it is a circuit topology diagram of the fault detection circuit.

[0061] For other structures of the reverse connection protection circuit and the vehicle refrigerator compressor controller described in this embodiment, refer to the prior art.

[0062] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Therefore, any modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A reverse connection protection circuit, which is used in a vehicle refrigerator compressor controller, characterized in that: The reverse connection protection circuit comprises: A MOS tube, wherein the drain of the MOS tube is connected to the negative electrode of the external input circuit, and the source of the MOS tube is connected to the negative electrode output terminal of the external input circuit; A voltage-dividing resistor, one end of which is connected to the positive electrode of the external input circuit, the other end of which is connected to the negative electrode of a voltage-stabilizing diode, and the other end of which is also connected to the gate of the MOS tube; A voltage stabilizing diode, wherein the positive electrode of the voltage stabilizing diode is connected to the source electrode of the MOS tube, and the negative electrode of the voltage stabilizing diode is also connected to the gate electrode of the MOS tube; The gate of the MOS tube is also connected to a main control chip, and the main control chip is used to control the subsequent circuit to stop.

2. A vehicle refrigerator compressor controller, characterized in that: Including a connected power supply circuit and a main control chip; The power supply circuit includes the reverse connection protection circuit according to claim 1, and the main control chip is connected to the reverse connection protection circuit.

3. A vehicle refrigerator compressor controller according to claim 2, characterized in that: The car refrigerator compressor controller includes: Main control chip; A power supply circuit, wherein the power supply circuit is connected to the main control chip; A PWM buffer circuit, wherein the PWM buffer circuit is connected to the main control chip; An IPM inverter drive circuit is connected to the PWM buffer circuit, and the IPM inverter drive circuit is connected to a vehicle-mounted compressor.

4. A vehicle refrigerator compressor controller according to claim 3, characterized in that: The car refrigerator compressor controller includes: An ADC sampling circuit is connected to the main control chip.

5. The vehicle refrigerator compressor controller according to claim 3, characterized in that: The car refrigerator compressor controller includes: A fault detection circuit is connected to the main control chip, and the fault detection circuit is connected to the IPM inverter drive circuit.

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