Power supply anti-reverse connection circuit and power supply system of automobile electric steering control motor

Abstract

The utility model relates to a power supply anti-reverse connection circuit and a power supply system of an automobile electric steering control motor, the anti-reverse connection circuit comprises a triode Q1, an MOS tube Q2, a first terminal, a second terminal, a third terminal and a fourth terminal, the emitter of the triode Q1 is electrically connected with the first terminal, and the base of the triode Q1 is electrically connected with the second terminal; the third terminal is electrically connected with the collector electrode of the triode Q1 and the grid electrode of the MOS tube Q2, the source electrode of the MOS tube Q2 is electrically connected with the first terminal, and the drain electrode of the MOS tube Q2 is electrically connected with the fourth terminal; the third terminal is used for accessing a power supply driving signal of an automobile electric steering control motor, and the fourth terminal is used for connecting a power supply end of the automobile electric steering control motor; the first terminal and the second terminal are respectively used for connecting two electrodes of an external direct-current power supply of the automobile electric steering control motor; compared with the prior art, the utility model has lower power consumption.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile electric steering systems, in particular to a power supply reverse connection prevention circuit and a power supply system of an automobile electric steering control motor. Background Art

[0002] With the rapid development of electrification in the automotive industry, steering control is developing in the direction of wire control, and the requirements for steering controllers (EPSECU) are getting higher and higher. In the prior art, the anti-reverse connection circuit of the motor power supply of the automobile steering system is either too small in power or too large in size, making it difficult to place in a limited space. For example, when a rectifier diode is used to construct an anti-reverse connection circuit, if the current is too small, the conduction voltage will increase, which will cause the rectifier diode to lose more power and may reduce the life of the rectifier diode. If the current is too large, the rectifier diode may be damaged by overheating. Therefore, the existing anti-reverse connection circuit of the motor power supply of the automobile steering system will lose more power. Utility Model Content

[0003] In order to solve the technical problem in the prior art that a rectifier diode used as an anti-reverse connection circuit for the motor power supply of an automobile steering system will cause more power loss, the utility model provides an anti-reverse connection circuit and a power supply system for an automobile electric steering control motor.

[0004] The technical solution of the utility model to solve the above technical problems is as follows:

[0005] A power reverse connection prevention circuit for an automobile electric steering control motor comprises a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal, wherein the first switch unit comprises a transistor Q1, and the second switch unit comprises a MOS transistor Q2; the emitter of the transistor Q1 is electrically connected to the first terminal, and the base of the transistor Q1 is electrically connected to the second terminal; the third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS transistor Q2, respectively, the source of the MOS transistor Q2 is electrically connected to the first terminal, and the drain of the MOS transistor Q2 is electrically connected to the fourth terminal; the third terminal is used to access a power supply drive signal of the automobile electric steering control motor, and the fourth terminal is used to connect a power supply terminal of the automobile electric steering control motor; the first terminal and the second terminal are respectively used to connect two electrodes of an external DC power supply of the automobile electric steering control motor.

[0006] The beneficial effects of the utility model are as follows: when two electrodes of the external DC power supply are respectively connected to the first terminal and the second terminal, if the connection is normal, that is, the positive electrode of the external DC power supply is connected to the first terminal and the negative electrode of the external DC power supply is connected to the second terminal, the transistor Q1 is in an off state, the MOS tube is turned on, the fourth terminal is turned on with the first terminal, and the positive electrode of the external DC power supply can be normally connected to the power supply end of the automobile electric steering control motor to achieve normal power supply of the automobile steering control motor; if the connection is reversed, that is, the positive electrode of the external DC power supply is connected to the second terminal and the negative electrode of the external DC power supply is connected to the first terminal, the transistor Q1 is in an on state and the MOS tube is turned off; at the same time, the internal resistance of the MOS tube and the transistor is low, and the power consumption of the entire circuit is very low regardless of whether the external DC power supply is positively connected (normally connected) or reversely connected (reverse connected). Compared with the prior art, the utility model has lower power consumption.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, the first switch unit further includes a resistor R15, one end of the resistor R15 is electrically connected to the base of the transistor Q1, and the other end of the resistor R15 is electrically connected to the second wiring terminal.

[0009] The beneficial effect of adopting the above further solution is that, by setting the resistor R15, the base level of the transistor Q1 can be clamped at a low level when there is no driving signal, which can effectively prevent the transistor Q1 from being accidentally turned on.

[0010] Furthermore, the first switch unit further includes a first diode, an anode of the first diode is electrically connected to the emitter of the transistor Q1, and a cathode of the first diode is electrically connected to the first connection terminal.

[0011] The beneficial effect of adopting the above further solution is that the provision of the first diode can enable unidirectional conduction from the third terminal to the first terminal after the transistor Q1 is turned on.

[0012] Furthermore, the second switch unit further includes a second diode, an anode of the second diode is electrically connected to the source of the MOS transistor Q2, and a cathode of the second diode is electrically connected to the drain of the MOS transistor Q2.

[0013] The beneficial effect of adopting the above further scheme is that by connecting the second diode in parallel to the MOS tube Q2, the MOS tube can be protected. When the voltage of the ds poles (drain and source) of the MOS tube is too high, the parasitic diode will be broken down, thereby protecting the MOS tube from being damaged by the excessively high voltage. In addition, if the source and drain of the MOS tube are reversely connected, the parasitic diode can also prevent the circuit from burning out. Provide a reverse path. The setting of the parasitic diode can provide a path for the overcurrent generated by the inductor freewheeling or parasitic parameters, and can also provide protection when the voltage is mistakenly applied to the ds poles (drain and source), so as to prevent the reverse induced voltage from breaking down the MOS tube.

[0014] Furthermore, the voltage value of the power supply driving signal is 12V higher than the voltage value of the external DC power supply.

[0015] Furthermore, it is characterized in that: the MOS transistor Q2 is an N-channel MOS transistor.

[0016] The beneficial effect of adopting the above further solution is that the power consumption of a PMOS tube of the same power is greater than that of an NMOS tube, so the use of an N-channel MOS tube can further reduce the power consumption. Moreover, the price of an NMOS tube is cheaper than that of a PMOS tube under the same power parameters.

[0017] Furthermore, the internal resistance of the N-channel MOS tube is less than 1 milliohm.

[0018] Furthermore, the transistor Q1 is an NPN transistor.

[0019] In order to solve the above technical problems, the utility model also provides a power supply system for an automobile electric steering control motor, and its specific technical contents are as follows:

[0020] A power supply system for an automobile electric steering control motor comprises a power supply reverse connection prevention circuit, the power supply reverse connection prevention circuit comprises a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal, the first switch unit comprises a transistor Q1, the second switch unit comprises a MOS transistor Q2; the emitter of the transistor Q1 is electrically connected to the first terminal, the base of the transistor Q1 is electrically connected to the second terminal; the third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS transistor Q2, the source of the MOS transistor Q2 is electrically connected to the first terminal, and the drain of the MOS transistor Q2 is electrically connected to the fourth terminal; the third terminal is used to access a power supply drive signal of the automobile electric steering control motor, the fourth terminal is used to connect the power supply terminal of the automobile electric steering control motor; the first terminal and the second terminal are respectively used to connect two electrodes of an external DC power supply of the automobile electric steering control motor.

[0021] Furthermore, the first switch unit further includes a resistor R15, one end of the resistor R15 is electrically connected to the base of the transistor Q1, and the other end of the resistor R15 is electrically connected to the second wiring terminal.

[0022] Furthermore, the first switch unit further includes a first diode, an anode of the first diode is electrically connected to the emitter of the transistor Q1, and a cathode of the first diode is electrically connected to the first connection terminal.

[0023] Furthermore, the second switch unit further includes a second diode, an anode of the second diode is electrically connected to the source of the MOS transistor Q2, and a cathode of the second diode is electrically connected to the drain of the MOS transistor Q2.

[0024] Furthermore, the MOS transistor Q2 is an N-channel MOS transistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a circuit schematic diagram of a power reverse connection protection circuit for an automotive electric steering control motor in an embodiment of the utility model;

[0026] Figure 2 This is a schematic diagram of a normal wiring circuit of a power supply in an embodiment of the utility model. DETAILED DESCRIPTION

[0027] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0028] Example 1

[0029] like Figure 1As shown, this embodiment provides a power reverse connection protection circuit for an electric steering control motor of an automobile, comprising a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal, wherein the first switch unit comprises a transistor Q1, and the second switch unit comprises a MOS tube Q2; the emitter of the transistor Q1 is electrically connected to the first terminal, and the base of the transistor Q1 is electrically connected to the second terminal; the third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS tube Q2, respectively, the source of the MOS tube Q2 is electrically connected to the first terminal, and the drain of the MOS tube Q2 is electrically connected to the fourth terminal; the third terminal is used to access the power supply drive signal of the electric steering control motor of the automobile, and the fourth terminal is used to connect the power supply terminal of the electric steering control motor of the automobile; the first terminal and the second terminal are respectively used to connect the two electrodes of the external DC power supply of the electric steering control motor of the automobile. The MOS tube Q2 is an N-channel MOS tube. The PMOS tube of the same power consumes more power than the NMOS tube, so the use of the N-channel MOS tube can further reduce the power consumption. Among them, the internal resistance of the N-channel MOS tube is less than 1 milliohm, and the transistor Q1 is an NPN transistor.

[0030] Specifically, the first switch unit further includes a resistor R15, one end of which is electrically connected to the base of the transistor Q1, and the other end of which is electrically connected to the second terminal. By setting the resistor R15, the base level of the transistor Q1 can be clamped at a low level when there is no driving signal, which can effectively prevent the transistor Q1 from accidentally turning on.

[0031] The first switch unit further includes a first diode, the anode of the first diode is electrically connected to the emitter of the transistor Q1, and the cathode of the first diode is electrically connected to the first terminal. The first diode is configured to enable unidirectional conduction between the third terminal and the first terminal after the transistor Q1 is turned on.

[0032] The second switch unit also includes a second diode, the positive electrode of the second diode is electrically connected to the source of the MOS tube Q2, and the negative electrode of the second diode is electrically connected to the drain of the MOS tube Q2. By connecting the second diode in parallel to the MOS tube Q2, the MOS tube can be protected. When the voltage of the ds poles (drain and source) of the MOS tube is too high, the parasitic diode will be broken down, thereby protecting the MOS tube from being damaged by excessive voltage. In addition, if the source and drain of the MOS tube are reversed, the parasitic diode can also prevent the circuit from burning out. Provide a reverse path. The setting of the parasitic diode can provide a path for overcurrent generated by inductive freewheeling or parasitic parameters, and can also provide protection when the voltage is mistakenly applied to the ds poles (drain and source), so as to prevent the reverse induced voltage from breaking down the MOS tube.

[0033] like Figure 2 As shown, when the power supply VBAT and GND are normally connected, that is, the positive electrode of the external DC power supply is connected to the first terminal (VBAT terminal), and the negative electrode of the external DC power supply is connected to the second terminal (GND terminal). When the power is just turned on, VBAT is turned on through the parasitic diode in the MOS tube Q2, that is, the second diode. After the conduction, the gate g of the NMOS tube (MOS tube Q2) itself is connected to the high-side charge pump MOTOR_EN (third terminal) of the motor drive chip, and MOTOR (fourth terminal) is connected to the bridge circuit of the motor; the voltage value of the power supply drive signal is 12V higher than the voltage value of the external DC power supply, that is, the power supply drive signal The voltage value of the signal is (VBAT+12)V, so the voltage between the gate g and the source s of the NMOS tube is 12V, which is much larger than the turn-on voltage threshold of 3V, and the drain d and source s of the NMOS tube are turned on; since the internal resistance of the NMOS tube is only 1 milliohm, after being connected in parallel with the parasitic diode in the body, the overall internal resistance of the NMOS tube is less than 1 milliohm. If the power supply current is 100A, the power consumption of the NMOS tube is no more than 100mW; the base b of the transistor Q1 is connected to the resistor R15 and grounded, the collector c of the transistor Q1 is connected to MOTOR_EN, the emitter of the transistor Q1 is connected to the positive electrode of the diode D2, and the negative electrode of D2 is connected to the power supply VBAT. In this state, the Q1 transistor is in the cut-off state.

[0034] The power supply VBAT is reversely connected to GND, that is, the positive pole of the external DC power supply is connected to the second terminal (GND terminal), and the negative pole of the external DC power supply is connected to the first terminal (VBAT terminal). The transistor Q1 is turned on, and the collector C voltage of the transistor Q1 is the voltage of GND (the second terminal), that is, the voltage is 0. The collector C of the transistor Q1 is connected to the gate g level of the NMOS tube (MOS tube Q2), and the gate g level is pulled down to 0, so the drain d and source s level of the NMOS tube are cut off, and the second diode is in the cut-off state, so the NMOS tube is in the cut-off state as a whole, and no voltage and current pass through, so that the positive and negative poles of the power supply of the automobile electric steering control motor are connected normally, and the automobile electric steering control motor is powered normally; after the positive and negative poles of the power supply of the automobile electric steering control motor are reversely connected, the automobile electric steering control motor cannot be powered normally.

[0035] Example 2

[0036] Based on Example 1, this embodiment provides a power supply system for an electric steering control motor of an automobile, including the power reverse connection protection circuit in Example 1, the power reverse connection protection circuit includes a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal, the first switch unit includes a transistor Q1, the second switch unit includes a MOS transistor Q2; the emitter of the transistor Q1 is electrically connected to the first terminal, the base of the transistor Q1 is electrically connected to the second terminal; the third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS transistor Q2, the source of the MOS transistor Q2 is electrically connected to the first terminal, and the drain of the MOS transistor Q2 is electrically connected to the fourth terminal; the third terminal is used to access the power supply drive signal of the electric steering control motor of the automobile, the fourth terminal is used to connect the power supply terminal of the electric steering control motor of the automobile; the first terminal and the second terminal are respectively used to connect the two electrodes of the external DC power supply of the electric steering control motor of the automobile. Wherein, the MOS transistor Q2 is an N-channel MOS transistor.

[0037] Specifically, the first switch unit further includes a resistor R15 and a first diode, one end of the resistor R15 is electrically connected to the base of the transistor Q1, and the other end of the resistor R15 is electrically connected to the second terminal. The first switch unit further includes that the anode of the first diode is electrically connected to the emitter of the transistor Q1, and the cathode of the first diode is electrically connected to the first terminal.

[0038] The second switch unit further includes a second diode, an anode of the second diode is electrically connected to the source of the MOS transistor Q2, and a cathode of the second diode is electrically connected to the drain of the MOS transistor Q2.

[0039] In the embodiment of the utility model, when the two electrodes of the external DC power supply are respectively connected to the first terminal and the second terminal, if the connection is normal, that is, the positive electrode of the external DC power supply is connected to the first terminal and the negative electrode of the external DC power supply is connected to the second terminal, the transistor Q1 is in the off state, the MOS tube is turned on, the fourth terminal is turned on with the first terminal, and the positive electrode of the external DC power supply can be normally connected to the power supply end of the automobile electric steering control motor to achieve normal power supply of the automobile steering control motor; if the connection is reversed, that is, the positive electrode of the external DC power supply is connected to the second terminal and the negative electrode of the external DC power supply is connected to the first terminal, the transistor Q1 is in the on state and the MOS tube is turned off; at the same time, the internal resistance of the MOS tube and the transistor is low, and the power consumption of the entire circuit is very low regardless of whether the external DC power supply is positively connected (normally connected) or reversely connected (reverse connected). Compared with the prior art, the utility model has lower power consumption.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A power reverse connection protection circuit for an automobile electric steering control motor, characterized in that: The invention comprises a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal, wherein the first switch unit comprises a transistor Q1, and the second switch unit comprises a MOS transistor Q2; the emitter of the transistor Q1 is electrically connected to the first terminal, and the base of the transistor Q1 is electrically connected to the second terminal; the third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS transistor Q2, respectively, the source of the MOS transistor Q2 is electrically connected to the first terminal, and the drain of the MOS transistor Q2 is electrically connected to the fourth terminal; the third terminal is used to access the power supply drive signal of the electric steering control motor of the automobile, and the fourth terminal is used to connect the power supply terminal of the electric steering control motor of the automobile; the first terminal and the second terminal are respectively used to connect the two electrodes of the external DC power supply of the electric steering control motor of the automobile.

2. The power reverse connection protection circuit of the electric power steering control motor of an automobile according to claim 1, characterized in that: The first switch unit further includes a resistor R15, one end of the resistor R15 is electrically connected to the base of the transistor Q1, and the other end of the resistor R15 is electrically connected to the second wiring terminal.

3. The power reverse connection protection circuit of the electric power steering control motor of an automobile according to claim 2, characterized in that: The first switch unit further includes a first diode, an anode of the first diode is electrically connected to the emitter of the transistor Q1, and a cathode of the first diode is electrically connected to the first connection terminal.

4. The power reverse connection protection circuit of the electric power steering control motor of an automobile according to claim 1, characterized in that: The second switch unit further includes a second diode, an anode of the second diode is electrically connected to the source of the MOS transistor Q2, and a cathode of the second diode is electrically connected to the drain of the MOS transistor Q2.

5. The power reverse connection protection circuit of the electric power steering control motor of an automobile according to claim 1, characterized in that: The voltage value of the power supply driving signal is 12V higher than the voltage value of the external DC power supply.

6. The power reverse connection protection circuit of the automotive electric power steering control motor according to claim 1, characterized in that: The MOS transistor Q2 is an N-channel MOS transistor.

7. The power reverse connection protection circuit of the automotive electric power steering control motor according to claim 6, characterized in that: The internal resistance of the N-channel MOS tube is less than 1 milliohm.

8. The power reverse connection protection circuit of the automotive electric power steering control motor according to claim 1, characterized in that: The transistor Q1 is an NPN transistor.

9. A power supply system for an automotive electric steering control motor, characterized in that: The invention comprises a power reverse connection protection circuit, which comprises a first switch unit, a second switch unit, a first terminal, a second terminal, a third terminal and a fourth terminal. The first switch unit comprises a transistor Q1, and the second switch unit comprises a MOS transistor Q2. The emitter of the transistor Q1 is electrically connected to the first terminal, and the base of the transistor Q1 is electrically connected to the second terminal. The third terminal is electrically connected to the collector of the transistor Q1 and the gate of the MOS transistor Q2, respectively, the source of the MOS transistor Q2 is electrically connected to the first terminal, and the drain of the MOS transistor Q2 is electrically connected to the fourth terminal. The third terminal is used to access the power supply drive signal of the electric steering control motor of the automobile, and the fourth terminal is used to connect the power supply terminal of the electric steering control motor of the automobile. The first terminal and the second terminal are respectively used to connect the two electrodes of the external DC power supply of the electric steering control motor of the automobile.

10. The power supply system of the automotive electric power steering control motor according to claim 9, characterized in that: The MOS transistor Q2 is an N-channel MOS transistor.

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