Motor controller reverse connection prevention circuit

Abstract

The utility model discloses a motor controller prevents the circuit of reverse connection, be equipped with PWM signal controller in motor controller, including MOS pipe Q1 and MOS pipe Q2, the positive terminal of power supply of motor controller connects the drain of MOS pipe Q1, the source of MOS pipe Q1 connects the source of MOS pipe Q2, the drain of MOS pipe Q2 is grounded, the gate of MOS pipe Q1 is connected PWM signal controller through resistance R1, the gate of MOS pipe Q2 is connected the drive voltage end of motor controller through resistance R4. When the power of motor controller is connected reversely, there is no drive voltage input in motor controller, namely, motor controller will only stop normal work because of positive and negative pole reverse connection and will not damage component, can work normally after correcting after discovering power reverse connection in time, plays better anti -reversing effect, and the reliability is high, and the utility model circuit is simple, and the cost is relatively low.

Description

Technical Field

[0001] This utility model relates to the field of reverse connection protection circuit technology, and more specifically to a reverse connection protection circuit for a motor controller. Background Technology

[0002] In modern electrical systems, the motor controller, as the core control unit, plays a crucial role in the normal operation of the entire electrical system due to its stability and reliability. However, in actual operation, due to human error or incorrect wiring, the positive and negative terminals of the motor controller are often reversed. Once this happens, a huge current surge is often generated instantly, which can easily damage the internal chips of the motor controller, thereby causing electrical system failures or even safety accidents.

[0003] Therefore, reverse connection protection circuits are incorporated into motor controllers. While traditional reverse connection protection circuits provide some protection, they still have certain problems. For example, some simple reverse connection protection circuits have limited protection effectiveness under complex operating conditions of high current and high voltage, and cannot effectively prevent damage caused by reverse connection of the positive and negative terminals of the motor controller. Furthermore, some reverse connection protection circuits are prone to damage to their internal components after repeated reverse connections, leading to the failure of the protection function and the inability to achieve reliable protection multiple times. In addition, some reverse connection protection circuits have complex circuit designs and high costs, which is not conducive to their widespread use in various types of motor controllers.

[0004] In view of this, this application has conducted in-depth research on this basis, resulting in this case. Utility Model Content

[0005] The purpose of this invention is to provide a reverse connection protection circuit for motor controllers that provides long-term reliable protection, has good protection effect, and is low in cost.

[0006] To achieve the above objectives, the solution of this utility model is:

[0007] A reverse connection protection circuit for a motor controller is disclosed. The motor controller includes a PWM signal controller and two MOSFETs, Q1 and Q2. The positive terminal of the power supply of the motor controller is connected to the drain of MOSFET Q1, the source of MOSFET Q1 is connected to the source of MOSFET Q2, the drain of MOSFET Q2 is grounded, the gate of MOSFET Q1 is connected to the PWM signal controller through a resistor R1, and the gate of MOSFET Q2 is connected to the drive voltage terminal of the motor controller through a resistor R4.

[0008] It also includes an overcurrent detection resistor assembly. The motor controller has an external or internal overcurrent signal detection module. The drain of the MOS transistor Q2 is connected to the first terminal of the overcurrent detection resistor assembly and the detection terminal of the overcurrent signal detection module, respectively. The second terminal of the overcurrent detection resistor assembly is grounded.

[0009] The overcurrent detection resistor assembly includes several resistors, each of which corresponds to resistor R5, resistor R6, resistor R7, resistor R8, and resistor R9. The first terminals of resistors R5, R6, R7, R8, and R9 are respectively the first terminals of the overcurrent detection resistor assembly. The first terminals of resistors R5, R6, R7, R8, and R9 are all connected to the drain of the MOSFET Q2 and the detection terminal of the overcurrent signal detection module, respectively. The second terminals of resistors R5, R6, R7, R8, and R9 are all grounded.

[0010] Both MOS transistors Q1 and Q2 are N-channel MOS transistors.

[0011] A resistor R2 is connected between the source and the gate of the MOS transistor Q1.

[0012] A resistor R3 is connected between the source and the gate of the MOS transistor Q2.

[0013] The positive terminal of the power supply of the motor controller is connected to the drain of the MOSFET Q1 via diode D1.

[0014] With the above structure, this utility model has the following beneficial effects: This utility model uses a reverse connection protection circuit formed by two MOSFETs connected in series. When the positive and negative terminals of the motor controller are reversed, its driving voltage cannot be generated. At this time, the PWM signal controller outputs a high level to pull up the gate voltage of MOSFET Q1, so that there is no voltage difference between the drain and source of MOSFET Q1. Then, the drain of MOSFET Q2 pulls up the source voltage. At this time, MOSFET Q2 turns off MOSFET Q1, so that there is no driving voltage input inside the motor controller. That is, the motor controller will only stop working normally due to the reverse connection of the positive and negative terminals and will not damage the components. After the reverse connection is detected in time, it can be corrected to work normally. It has a better reverse connection protection effect, high reliability, and the circuit of this utility model is simple and the cost is relatively low. Attached Figure Description

[0015] Figure 1 This is a circuit diagram of the reverse connection protection circuit for the motor controller of this utility model. Detailed Implementation

[0016] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0017] A reverse connection protection circuit for a motor controller, such as Figure 1 As shown, it is connected to the circuit of the motor controller. The motor controller can be any type of motor controller that is already available on the market. The circuit of a conventional motor controller has a positive power terminal (VCC terminal) and a negative power terminal (i.e., ground terminal, also known as GND terminal). In this embodiment, the positive power terminal (VCC terminal) is connected to the negative power terminal (GND terminal) through this utility model. The positive power terminal of the motor controller is connected to the positive power terminal of the power supply in the conventional way of motor controller, and the negative power terminal of the motor controller is connected to the negative power terminal of the power supply. The power supply is the power supply selected by the conventional motor controller, such as mains power or battery.

[0018] Furthermore, in this embodiment, a conventional motor controller generates a driving voltage internally, and the port in this embodiment that outputs the driving voltage is the driving voltage terminal described below.

[0019] It should be noted that conventional motor controllers all have overcurrent signal detection functions, that is, conventional motor controllers have an external or integrated overcurrent signal detection module. The overcurrent signal detection module is an existing conventional overcurrent signal detection module, which will not be described in detail here. The overcurrent signal detection module is equipped with a detection terminal for collecting overcurrent signals.

[0020] The improvement of this utility model is that the above-mentioned reverse connection protection circuit for the motor controller includes MOSFET Q1, MOSFET Q2, and a PWM signal controller. The VCC terminal of the motor controller is connected to the cathode of diode D1, the anode of diode D1 is connected to the drain of MOSFET Q1, the source of MOSFET Q1 is connected to the source of MOSFET Q2, and the drain of MOSFET Q2 is connected to the GND terminal, i.e., MOSFETs Q1 and Q2 are connected in series. The gate of MOSFET Q1 is connected to the signal output terminal of the PWM signal controller through resistor R1, and the gate of MOSFET Q2 is connected to the motor through resistor R4. The controller's drive voltage terminal (i.e., VCC-DRV terminal); wherein, a resistor R2 is connected between the source and gate of MOSFET Q1, that is, the first end of resistor R1 is connected to the first end of resistor R4, and the second end of resistor R2 is connected to the source of MOSFET Q1. This resistor R2 is used to limit the conductivity of the MOSFET; a resistor R3 is connected between the source and gate of MOSFET Q2, that is, the first end of resistor R3 is connected to the first end of resistor R4, and the second end of resistor R3 is connected to the source of MOSFET Q2. This resistor R3 is used to limit the conductivity of the MOSFET.

[0021] Furthermore, in this embodiment, a power supply terminal is led out between the positive terminal of the diode D1 and the drain of the MOSFET Q1. This power supply terminal is connected to the power output terminal of the motor controller to provide operating power to the entire motor controller.

[0022] Furthermore, the aforementioned PWM signal controller is an internal module of the aforementioned motor controller, and motor controllers with PWM signal control modules are common operating procedures, so they will not be described in detail here.

[0023] Furthermore, both MOSFETs Q1 and Q2 mentioned above are N-channel MOSFETs.

[0024] Furthermore, this utility model also includes an overcurrent detection resistor assembly. The drain of the MOSFET Q2 is split into two paths: one path is connected to the GND terminal through the overcurrent detection resistor assembly, and the other path is connected to the detection terminal of the aforementioned overcurrent signal detection module.

[0025] To elaborate, the aforementioned overcurrent detection resistor assembly includes several resistors. In this embodiment, each resistor corresponds to resistor R5, resistor R6, resistor R7, resistor R8, and resistor R9. The first terminals of resistors R5, R6, R7, R8, and R9 are all the first terminals of the overcurrent detection resistor assembly. That is, the drain of MOSFET Q2 is connected to the first terminals of resistors R5, R6, R7, R8, and R9, as well as the detection terminal of the overcurrent signal detection module. The second terminals of resistors R5, R6, R7, R8, and R9 are all connected to the GND terminal. In other words, resistors R5, R6, R7, R8, and R9 are connected in parallel.

[0026] In this way, when the overcurrent signal detection module detects an overcurrent signal, the motor controller controls the PWM signal controller to switch from a high level to a low level, so as to turn off the MOSFET Q1 and thus stop the motor controller from working, so as to avoid damage to the internal components of the motor controller due to overcurrent.

[0027] This utility model discloses a reverse connection protection circuit for a motor controller. Its working principle is as follows: When the motor controller is operating normally, it outputs a drive voltage when its positive and negative power supply terminals are correctly connected. This means the motor controller is connected to power, causing the gate of MOSFET Q2 to pull up its source voltage, thus turning on MOSFET Q2. With the drain of MOSFET Q2 connected to the negative terminal, the positive power supply terminal of the motor controller pulls up the source voltage of MOSFET Q2. The PWM signal controller outputs a high level to pull up the gate voltage of MOSFET Q1, which in turn pulls up the source voltage of MOSFET Q1, thus turning on MOSFET Q1. At this time, the motor controller operates normally.

[0028] When the positive and negative terminals of the motor controller are reversed, the motor controller will not generate a drive voltage because it is not connected to a power source. At the same time, the PWM signal controller outputs a high level to pull up the gate voltage of MOSFET Q1, thereby eliminating the voltage difference between the drain and source of MOSFET Q1. This, in turn, pulls up the drain-to-source voltage of MOSFET Q2, allowing MOSFET Q2 to turn off MOSFET Q1. During the turn-off process of MOSFETs Q1 and Q2, the power supply voltage cannot enter the motor controller, thus providing protection.

[0029] It is worth mentioning that in actual use, when the positive and negative terminals of the motor controller are reversed and different voltages are input, MOSFET Q2 always keeps MOSFET Q1 in the off state.

[0030] This utility model discloses a reverse connection protection circuit for a motor controller. It is applied to the circuit of a motor controller and selects corresponding circuit parameters for different input voltages. Two MOSFETs are connected in series to form a reverse connection protection circuit, which enhances the reverse connection protection capability of the motor controller. Compared with traditional reverse connection protection circuits, the motor controller will only stop working normally without damaging the components when the power supply is reversed. After the reverse connection is detected in time, it can be corrected to resume normal operation, saving the cost of troubleshooting.

[0031] The above description is only a preferred embodiment of this invention. All equivalent changes and modifications made within the scope of the claims of this utility model shall fall within the scope of the claims of this utility model.

Claims

1. A reverse connection protection circuit for a motor controller, wherein the motor controller includes a PWM signal controller, characterized in that: The system includes MOSFETs Q1 and Q2. The positive terminal of the power supply of the motor controller is connected to the drain of MOSFET Q1, the source of MOSFET Q1 is connected to the source of MOSFET Q2, the drain of MOSFET Q2 is grounded, the gate of MOSFET Q1 is connected to the PWM signal controller through resistor R1, and the gate of MOSFET Q2 is connected to the drive voltage terminal of the motor controller through resistor R4.

2. The reverse connection protection circuit for a motor controller according to claim 1, characterized in that: It also includes an overcurrent detection resistor assembly. The motor controller has an external or internal overcurrent signal detection module. The drain of the MOS transistor Q2 is connected to the first terminal of the overcurrent detection resistor assembly and the detection terminal of the overcurrent signal detection module, respectively. The second terminal of the overcurrent detection resistor assembly is grounded.

3. The reverse connection protection circuit for a motor controller according to claim 2, characterized in that: The overcurrent detection resistor assembly includes several resistors, each of which corresponds to resistor R5, resistor R6, resistor R7, resistor R8, and resistor R9. The first terminals of resistors R5, R6, R7, R8, and R9 are respectively the first terminals of the overcurrent detection resistor assembly. The first terminals of resistors R5, R6, R7, R8, and R9 are all connected to the drain of the MOSFET Q2 and the detection terminal of the overcurrent signal detection module, respectively. The second terminals of resistors R5, R6, R7, R8, and R9 are all grounded.

4. A reverse connection protection circuit for a motor controller according to claim 1, 2, or 3, characterized in that: Both MOS transistors Q1 and Q2 are N-channel MOS transistors.

5. The reverse connection protection circuit for a motor controller according to claim 4, characterized in that: A resistor R2 is connected between the source and the gate of the MOS transistor Q1.

6. The reverse connection protection circuit for a motor controller according to claim 5, characterized in that: A resistor R3 is connected between the source and the gate of the MOS transistor Q2.

7. The reverse connection protection circuit for a motor controller according to claim 4, characterized in that: The positive terminal of the power supply of the motor controller is connected to the drain of the MOSFET Q1 via diode D1.

Images