Gear speed regulation circuit with overvoltage and undervoltage protection and motor controller

Abstract

The utility model discloses a gear speed regulation circuit with overvoltage and undervoltage protection and a motor controller, which comprise a plurality of gear speed regulation circuits which are optical coupling isolation processing circuits, and are characterized in that two input ends of the optical coupling isolation processing circuits are connected with a voltage protection circuit; the voltage protection circuit comprises an under-voltage protection circuit and an over-voltage protection circuit. According to the utility model, overvoltage protection and undervoltage protection are integrated, component parameters can be adjusted to set an overvoltage point and an undervoltage point, the operation is simple, and the threshold value triggered by gears is very accurate; the anti-interference capability is strong, and the reliability is improved; components are common, high in mutual replaceability, low in cost and easy to purchase.

Description

Technical Field

[0001] The utility model relates to a gear speed regulating circuit with overvoltage and undervoltage protection and a motor controller. Background Art

[0002] In the speed control system of the industrial control field, it is often necessary to control the terminal equipment (such as motors) through analog signals. In order to ensure the safety between the input and output and the interference of the control signals, the signals at both ends need to be isolated. Therefore, a reliable signal isolation output technology is widely demanded.

[0003] In motor control, multiple gear speed control is usually set. Analog signal gear speed control is generally achieved by isolating and transmitting analog signals through linear optical couplers, such as Figure 1 As shown, the linear optocoupler can effectively isolate the analog voltage signal input on the primary side and transmit it to the secondary side, and then sample and process it through the processor on the secondary side. This method is undoubtedly simple in circuit, but the linear optocoupler is expensive. In addition, the circuit has poor anti-interference ability and the threshold of gear triggering is not accurate. It is easy to mistakenly trigger other gears, causing abnormal gear speed regulation function of the motor. Figure 2 The figure shows another multi-speed control method, which generally uses digital optical couplers to achieve isolated transmission of analog signals. This method also has the disadvantages of poor anti-interference ability and inaccurate threshold value of gear triggering. Summary of the Invention

[0004] The purpose of the utility model is to provide a gear speed control circuit and a motor controller with overvoltage and undervoltage protection, so as to solve the technical problems in the prior art that the gear speed control circuit adopts optical coupling isolation transmission technology, has poor anti-interference ability and inaccurate gear triggering threshold.

[0005] The technical solution of the present utility model is achieved as follows:

[0006] A gear speed regulation circuit with overvoltage and undervoltage protection includes several gear speed regulation circuits. The gear speed regulation circuit is an optocoupler isolation processing circuit, which is characterized in that the two input ends of the optocoupler isolation processing circuit are connected to the voltage protection circuit, and the voltage protection circuit includes an undervoltage protection circuit and an overvoltage protection circuit.

[0007] The under-voltage protection circuit comprises a resistor R13, a transistor Q1, a transistor Q2, a resistor R14 and a Zener diode ZD5. The gear input signal In1 is connected to the Zener diode ZD1 and then to an input pin of the optical coupling isolation processing circuit. The gear input signal In1 is connected to the diode D1 and then to one end of the resistor R13. The other end of the resistor R13 is connected to the emitter of the transistor Q1. One end of the resistor R14 is connected to the base of the transistor Q1. The other end of the resistor R14 is connected to the negative electrode of the Zener diode ZD5. The positive electrode of the Zener diode ZD5 is connected to the ground GND. The collector of the transistor Q1 is connected to the base of the transistor Q2. The emitter of the transistor Q2 is connected to the ground GND. The collector of the transistor Q2 is connected to the other input pin of the optical coupling isolation processing circuit.

[0008] The over-voltage protection circuit comprises a Zener diode ZD4, a resistor R15, a resistor R16 and a transistor Q3. The negative electrode of the Zener diode ZD4 is connected to the emitter of the transistor Q1. The resistor R15 and the resistor R16 are connected in series. One end of the series connection is connected to the positive electrode of the Zener diode ZD4. The other end is connected to the ground GND. The base of the transistor Q3 is connected between the resistor R15 and the resistor R16. The emitter of the transistor Q3 is connected to the ground GND. The collector of the transistor Q3 is connected to the base of the transistor Q2.

[0009] The gear speed regulation circuit has three paths. The first path gear speed regulation circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a capacitor C1, a capacitor C2 and an optical coupling U1. The gear input signal In1 is connected to the Zener diode ZD1 and then to an input pin of the first path gear speed regulation circuit. The second path gear speed regulation circuit comprises a resistor R5, a resistor R6, a resistor R7, a resistor R8, a capacitor C3, a capacitor C4 and an optical coupling U2. The gear input signal In2 is connected to the Zener diode ZD2 and then to an input pin of the second path gear speed regulation circuit. The third path gear speed regulation circuit comprises a resistor R9, a resistor R10, a resistor R11, a resistor R12, a capacitor C5, a capacitor C6 and an optical coupling U3. The gear input signal In3 is connected to the Zener diode ZD3 and then to an input pin of the third path gear speed regulation circuit.

[0010] The parameters of the Zener diode ZD1, the Zener diode ZD2 and the Zener diode ZD3 are set to avoid the false triggering of the gear input signal In1, the gear input signal In2 and the gear input signal In3 caused by mutual interference.

[0011] A motor controller comprises a microprocessor and a plurality of gear speed regulation circuits. A plurality of gear input signals are connected to the input ends of the plurality of gear speed regulation circuits. The output ends of the plurality of gear speed regulation circuits are connected to the microprocessor. The gear speed regulation circuit adopts the gear speed regulation circuit with over-voltage and under-voltage protection as described above.

[0012] Compared with the prior art, the utility model has the following advantages:

[0013] 1. Integrated overvoltage and undervoltage protection, you can adjust the component parameters to set the overvoltage point and undervoltage point, the operation is simple, and the gear trigger threshold is very accurate;

[0014] 2. Strong anti-interference ability and improved reliability;

[0015] 3. Components are common, highly interchangeable, low cost and easy to purchase. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a circuit diagram of a mid-gear speed regulating circuit in the prior art;

[0017] Figure 2 It is the corresponding circuit diagram of the multi-speed regulating circuit in the prior art;

[0018] Figure 3 This is a circuit block diagram of the first embodiment of the present utility model;

[0019] Figure 4 yes Figure 3 Corresponding circuit diagram;

[0020] Figure 5 This is a circuit block diagram of the second embodiment of the present utility model;

[0021] Figure 6 yes Figure 5 Corresponding circuit diagram;

[0022] Figure 7 This is a circuit block diagram of the third embodiment of the present utility model. DETAILED DESCRIPTION

[0023] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] Example 1:

[0025] like Figures 3 and 4 As shown, this embodiment provides a gear speed control circuit with overvoltage and undervoltage protection, including several gear speed control circuits. The gear speed control circuit is an optocoupler isolation processing circuit, which is characterized in that the two input ends of the optocoupler isolation processing circuit are connected to the voltage protection circuit, and the voltage protection circuit includes an undervoltage protection circuit and an overvoltage protection circuit.

[0026] The undervoltage protection circuit includes a resistor R13, a transistor Q1, a transistor Q2, a resistor R14 and a Zener diode ZD5. The gear input signal In1 is connected to the Zener diode ZD1 and then connected to an input pin of the optocoupler isolation processing circuit. The gear input signal In1 is connected to the diode D1 and then connected to one end of the resistor R13. The other end of the resistor R13 is connected to the emitter of the transistor Q1, the base of the transistor Q1 is connected to one end of the resistor R14, the other end of the resistor R14 is connected to the cathode of the Zener diode ZD5, and the anode of the Zener diode ZD5 is grounded GND; the collector of the transistor Q1 is connected to the base of the transistor Q2, the emitter of the transistor Q2 is grounded GND, and the collector of the transistor Q2 is connected to another input pin of the optocoupler isolation processing circuit.

[0027] The above-mentioned overvoltage protection circuit includes a Zener diode ZD4, a resistor R15, a resistor R16 and a transistor Q3. The cathode of the Zener diode ZD4 is connected to the emitter of the transistor Q1. The resistors R15 and R16 are connected in series, one end of which is connected to the anode of the Zener diode ZD4 and the other end is grounded GND. The base of the transistor Q3 is connected between the resistors R15 and R16. The emitter of the transistor Q3 is grounded GND. The collector of the transistor Q3 is connected to the base of the transistor Q2.

[0028] The gear speed control circuit includes resistors R1, R2, R3, R4, capacitors C1, C2, and an optocoupler U1. The gear input signal In1 is connected to the voltage regulator diode ZD1 and then connected to an input pin of the first gear speed control circuit.

[0029] The working principle of the utility model is: the speed control signal is given to "In1", and reaches the emitter of the transistor Q1 through the diode D1 and the resistor R13. If the speed control signal voltage is not enough, it cannot break through the voltage-stabilizing diode DZ5. At this time, the circuit is in an undervoltage protection state. When the speed control signal voltage In1 can break through the diode DZ5, the transistor Q1 is turned on. When the voltage Vbe between the base and emitter of the transistor Q2 reaches 0.7V, the transistor Q2 is turned on. At this time, the speed control signal In1 passes through the voltage-stabilizing tube DZ1, the resistor R1, and the optocoupler. U1 and transistor Q2 are turned on, and then the output signal IO1 of the gear speed control circuit gives the speed control signal to the microprocessor MCU, and the motor system starts and runs in gear "1"; if the voltage amplitude of the speed control signal In1 continues to increase at this time, the voltage regulator diode DZ4 will be broken down, the transistor Q3 will be turned on, and the voltage Vbe between the base and emitter of the transistor Q2 will be pulled down, the transistor Q2 will be cut off and disconnected, the optocoupler U1 will be cut off and not conducting, the output signal IO1 of the gear speed control circuit will also be pulled low, the motor will not work, and the circuit will be in overvoltage protection state.

[0030] Example 2:

[0031] This embodiment is a modification based on embodiment one, as shown in Figure 5 and Figure 6 The above-mentioned gear speed regulation circuit has three paths, the first path gear speed regulation circuit includes resistors R1, R2, R3, R4, capacitors C1, C2 and optocoupler U1; the gear input signal In1 is connected to a stable voltage diode ZD1 and then to an input pin of the first path gear speed regulation circuit; the second path gear speed regulation circuit includes resistors R5, R6, R7, R8, capacitors C3, C4 and optocoupler U2; the gear input signal In2 is connected to a stable voltage diode ZD2 and then to an input pin of the second path gear speed regulation circuit; the third path gear speed regulation circuit includes resistors R9, R10, R11, R12, capacitors C5, C6 and optocoupler U3; the gear input signal In3 is connected to a stable voltage diode ZD3 and then to an input pin of the third path gear speed regulation circuit.

[0032] The input ends of the first path gear speed regulation circuit, the second path gear speed regulation circuit and the third path gear speed regulation circuit are connected to a voltage protection circuit, which has under-voltage and over-voltage protection functions.

[0033] The above-mentioned parameters of the stable voltage diodes ZD1, ZD2 and ZD3 are set to avoid false triggering of the gear input signals In1, In2 and In3 caused by mutual interference, greatly improving the anti-interference ability of the motor system.

[0034] Of course, this embodiment is only a three-gear gear speed regulation circuit, and a five-gear gear speed regulation circuit can also be set by those skilled in the art.

[0035] Embodiment three:

[0036] As shown in Figure 7 A motor controller, including a microprocessor, an inverter circuit, a rotor position detection circuit and a plurality of gear speed regulation circuits, a plurality of gear input signals are respectively connected to the input ends of the plurality of gear speed regulation circuits, and the output ends of the plurality of gear speed regulation circuits are connected to the microprocessor, characterized in that: the gear speed regulation circuit adopts the above-mentioned gear speed regulation circuit with over-voltage and under-voltage protection of embodiment one or embodiment two.

[0037] The above embodiments are the preferred embodiments of the present application, but the embodiments of the present application are not limited thereto, and any changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principles of the present application are equivalent replacement methods, which are all included in the protection scope of the present application.

Claims

1. A gear speed regulating circuit with overvoltage and undervoltage protection, including several gear speed regulating circuits, wherein the gear speed regulating circuit is an optocoupler isolation processing circuit, characterized in that: Two input terminals of the optocoupler isolation processing circuit are connected to a voltage protection circuit, which includes an undervoltage protection circuit and an overvoltage protection circuit.

2. The gear speed regulating circuit with overvoltage and undervoltage protection according to claim 1, characterized in that: The undervoltage protection circuit includes a resistor R13, a transistor Q1, a transistor Q2, a resistor R14 and a Zener diode ZD5. The gear input signal In1 is connected to the Zener diode ZD1 and then connected to an input pin of the optocoupler isolation processing circuit. The gear input signal In1 is connected to the diode D1 and then connected to one end of the resistor R13. The other end of the resistor R13 is connected to the emitter of the transistor Q1. The base of the transistor Q1 is connected to one end of the resistor R14. The other end of the resistor R14 is connected to the cathode of the Zener diode ZD5. The anode of the Zener diode ZD5 is grounded GND; the collector of the transistor Q1 is connected to the base of the transistor Q2, the emitter of the transistor Q2 is grounded GND, and the collector of the transistor Q2 is connected to another input pin of the optocoupler isolation processing circuit.

3. The gear speed regulating circuit with overvoltage and undervoltage protection according to claim 2, characterized in that: The overvoltage protection circuit includes a Zener diode ZD4, a resistor R15, a resistor R16, and a transistor Q3. The cathode of the Zener diode ZD4 is connected to the emitter of the transistor Q1. Resistors R15 and R16 are connected in series, one end of which is connected to the anode of the Zener diode ZD4, and the other end is grounded GND. The base of the transistor Q3 is connected between the resistors R15 and R16, the emitter of the transistor Q3 is grounded GND, and the collector of the transistor Q3 is connected to the base of the transistor Q2.

4. The gear speed regulating circuit with overvoltage and undervoltage protection according to claim 1, 2 or 3, characterized in that: There are three gear speed control circuits. The first gear speed control circuit includes resistors R1, R2, R3, R4, capacitors C1, C2, and optocoupler U1. The gear input signal In1 is connected to the Zener diode ZD1 and then connected to an input pin of the first gear speed control circuit. The second gear speed control circuit includes resistors R5, R6, R7, R8, capacitors C3, C4 and optocoupler U2; the gear input signal In2 is connected to the voltage regulator diode ZD2 and then connected to an input pin of the second gear speed control circuit; The third gear speed control circuit includes resistors R9, R10, R11, R12, capacitors C5, C6 and optocoupler U3; the gear input signal In3 is connected to the Zener diode ZD3 and then to an input pin of the third gear speed control circuit.

5. The gear speed regulating circuit with overvoltage and undervoltage protection according to claim 4, characterized in that: By setting the parameters of the Zener diodes ZD1 , ZD2 and ZD3 , the gear input signals In1 , In2 and In3 can avoid false triggering caused by mutual interference.

6. A motor controller comprising a microprocessor and a plurality of gear speed control circuits, wherein the plurality of gear input signals are connected to the input terminals of the plurality of gear speed control circuits, and the output terminals of the plurality of gear speed control circuits are connected to the microprocessor, characterized in that: The gear speed regulating circuit adopts the gear speed regulating circuit with overvoltage and undervoltage protection as described in any one of claims 1 to 5.

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