Circuit for inhibiting reverse rotation of motor

Abstract

The invention provides a circuit for inhibiting reverse rotation of a motor. The circuit comprises a time-delay power-on circuit and a power-off discharge circuit, the delay power-on circuit comprises a power supply input end, a discharge diode, a charging capacitor, a charging resistor, a thyristor, a voltage stabilizing diode, an enabling resistor, an enabling capacitor and an output diode. The power input end is connected with the cathode of the discharge diode. The anode of the discharge diode is connected with one end of the charging capacitor. The other end of the charging capacitor is connected with a grounding end; the charging resistor and the discharging diode are connected in parallel; the anode of the thyristor is connected with the power supply input end, the cathode of the thyristor is connected with the anode of the output diode, and the gate pole of the thyristor is connected with the anode of the voltage stabilizing diode; the cathode of the Zener diode is connected with the anode of the discharge diode; the power-off discharge circuit comprises a third resistor, a fourth resistor, a fifth resistor and a normally closed relay; the power input end is connected with the first control end through the third resistor. The circuit can provide two functions of motor time-delay power-on and motor reverse rotation inhibition.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a circuit for suppressing the reverse rotation of a motor. Background Art

[0002] Many devices include motors, e.g. Figure 1 As shown, the Stirling rotary refrigerator includes a motor 1, a cold end 2 and a hot end 3. The cold end 2 and the hot end 3 are connected. A piston 4 and a connecting rod 5 are respectively provided in the cold end 2 and the hot end 3. The connecting rod 5 is connected to the motor 1. After the motor 1 is powered on and rotated, the connecting rod 5 is driven to move the piston 4 back and forth. During the isothermal compression process, the gas in the cold end 2 and the hot end 3 is compressed and absorbs heat; during the isothermal expansion process, the gas expands and releases heat, so that the cold end 2 achieves the purpose of cooling.

[0003] However, reference Figure 1 As shown, when the motor 1 is powered off, the temperature of the cold end 2 is lower than the ambient temperature, the ambient temperature heats the cold end 2, the gas in the cold end 2 expands due to the heat and enters the hot end 3, the connecting rod 5 drives the motor 1 to reverse, the motor 1 reverses and the original cold end 2 becomes the hot end 3, the original hot end 3 becomes the cold end 2, the temperature of the original cold end 2 increases after becoming the hot end 3, and the refrigeration time is increased for the next refrigeration; in addition, refer to Figure 1 and Figure 2 As shown, when the motor 1 is reversed, the three terminals U, V, and W of the motor 1 generate reverse current I U ,I V ,I W , the reverse current flows to the voltage bus VBUS through the parasitic reverse parallel diode of the MOS tube in the upper bridge arm of the motor drive circuit, and generates a reverse electromotive force between the voltage bus VBUS and the ground terminal DGND. If the reverse electromotive force is too large, the circuit structure and mechanical structure of the Stirling rotary refrigerator may be damaged. Summary of the invention

[0004] The invention provides a circuit for suppressing the reverse rotation of a motor, so as to solve the technical problem that the reverse rotation occurs when the motor is powered off.

[0005] In order to solve the above technical problems, the present invention provides a circuit for inhibiting motor reversal, including a delayed power-on circuit and a power-off discharge circuit;

[0006] The delayed power-on circuit includes a power input terminal, a discharge diode, a charging capacitor, a charging resistor, a thyristor, a voltage regulator diode, an enable resistor, an enable capacitor and an output diode; the power input terminal is connected to the cathode of the discharge diode, and the anode of the discharge diode is connected to one end of the charging capacitor; the other end of the charging capacitor is connected to the ground terminal; the charging resistor and the discharge diode are connected in parallel; the anode of the thyristor is connected to the power input terminal, the cathode of the thyristor is connected to the anode of the output diode, and the gate of the thyristor is connected to the anode of the voltage regulator diode; the negative electrode of the voltage regulator diode is connected to the positive electrode of the discharge diode; one end of the enable resistor and the enable capacitor connected in parallel is connected to the gate of the thyristor, and the other end of the enable resistor and the enable capacitor connected in parallel is connected to the anode of the output diode; the negative electrode of the output diode is used to connect the voltage bus of the motor;

[0007] The power-off discharge circuit includes a third resistor, a fourth resistor, a fifth resistor and a normally closed relay; the normally closed relay includes a first control end, a second control end, a first output end and a second output end; the power input end is connected to the first control end through the third resistor; the second control end is connected to the ground end; one end of the fourth resistor is connected to the first output end, and the other end of the fourth resistor is connected to the negative electrode of the output diode; one end of the fifth resistor is connected to the second output end, and the other end of the fifth resistor is connected to the ground end.

[0008] Preferably, the normally closed relay is a normally closed optocoupler relay.

[0009] Preferably, the charging resistor is an adjustable resistor.

[0010] Preferably, the charging capacitor is an adjustable capacitor.

[0011] Preferably, the enabling resistor is an adjustable resistor.

[0012] Preferably, the enabling capacitor is an adjustable capacitor.

[0013] Preferably, the third resistor is an adjustable resistor.

[0014] Preferably, the fourth resistor is an adjustable resistor.

[0015] Preferably, the discharge diode is a high-speed diode.

[0016] Preferably, the output diode is a Schottky diode.

[0017] The invention provides a circuit for inhibiting motor reversal, comprising two modules: a delayed power-on circuit and a power-off discharge circuit, which can provide two functions of delayed motor power-on and inhibiting motor reversal. The working principle of the delayed power-on of the motor is as follows: when the DC voltage source supplies power to the power input terminal, the first control terminal of the normally closed relay is energized, the first control terminal and the second control terminal are disconnected, and the first output terminal and the second output terminal are also disconnected; the DC voltage source charges the charging capacitor through the power input terminal and the charging resistor, and the charging time can be adjusted by adjusting the size of the charging resistor and the charging capacitor, thereby adjusting the delay time of the delayed power-on of the motor; after the charging capacitor is charged to a certain voltage value, the voltage regulator diode is reversely conducted to provide an enable voltage to the gate of the thyristor; after the thyristor is turned on, the DC voltage source charges the enable resistor and the enable capacitor through the power input terminal and the thyristor, the thyristor remains in the on state, the voltage regulator diode is forwardly conducted, and the DC voltage source supplies power to the voltage bus of the motor through the power input terminal, the thyristor and the output diode, and the voltage bus of the motor supplies power to the motor through the drive circuit. After the motor rotates forward, the Stirling rotary refrigerator or other equipment containing the motor can work normally; by delaying the power-on of the motor, it can be avoided that the normally closed relay is not disconnected in time when the motor is powered on, causing the voltage bus to be connected to the ground terminal, resulting in the motor not being able to operate normally. The working principle of suppressing motor reversal is as follows: when the DC voltage source stops supplying power to the power input terminal, the first control terminal of the normally closed relay loses power, the first control terminal and the second control terminal are connected, and the first output terminal and the second output terminal are also connected; the charging capacitor releases the remaining potential energy through the discharge diode, the third resistor, the first output terminal, the second control terminal and the ground terminal; the enabling capacitor releases the remaining potential energy through the enabling resistor; the reverse electromotive force generated by the motor reversal is released through the motor's voltage bus, the fourth resistor, the first output terminal, the second output terminal, the fifth resistor and the ground terminal, thereby suppressing the motor reversal. If the reverse electromotive force generated by the motor reversal is small, this circuit can prevent the motor from reversing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a Stirling rotary refrigerator in the prior art.

[0019] Figure 2 The present invention is a schematic diagram of a circuit structure in the prior art for generating reverse electromotive force when a motor is reversed.

[0020] Figure 3 It is a schematic diagram of the structure of a circuit for suppressing motor reverse rotation provided by one embodiment of the present invention.

[0021] [Description of reference numerals is as follows]:

[0022] Motor-1, cold end-2, hot end-3, piston-4, connecting rod-5;

[0023] Voltage bus-VBUS, ground terminal-DGND;

[0024] Delayed power-on circuit-11, power-off discharge circuit-12;

[0025] Power input terminal-DCIN+, discharge diode-D1, charging capacitor-C1, charging resistor-R1, thyristor-T1, voltage regulator diode-D2, enable resistor-R2, enable capacitor-C2, output diode-D3;

[0026] The third resistor-R3, the fourth resistor-R4, the fifth resistor-R5, the normally closed relay-U1;

[0027] A first control terminal -LED+, a second control terminal -LED-, a first output terminal -OUT1, and a second output terminal -OUT2. DETAILED DESCRIPTION

[0028] In order to make the purpose, advantages and features of the present invention more clear, a circuit for suppressing motor reversal proposed by the present invention is further described in detail below in conjunction with the accompanying drawings. It should be noted that the accompanying drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0029] In the description of the present invention, the terms "first", "second", etc. are added for the convenience of description and reference, and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined by the terms "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0030] like Figure 3As shown, this embodiment provides a circuit for inhibiting motor reversal, including a delayed power-on circuit 11 and a power-off discharge circuit 12; the delayed power-on circuit 11 includes a power input terminal DCIN+, a discharge diode D1, a charging capacitor C1, a charging resistor R1, a thyristor T1, a voltage regulator diode D2, an enable resistor R2, an enable capacitor C2 and an output diode D3; the power input terminal DCIN+ is connected to the cathode of the discharge diode D1, and the anode of the discharge diode D1 is connected to one end of the charging capacitor C1; the other end of the charging capacitor C1 is connected to the ground terminal DGND; the charging resistor R1 and the discharge diode D1 are connected in parallel; the anode of the thyristor T1 is connected to the power input terminal DCIN+, the cathode of the thyristor T1 is connected to the anode of the output diode D3, and the gate of the thyristor T1 is connected to the anode of the voltage regulator diode D2; the cathode of the voltage regulator diode D2 is connected to the anode of the discharge diode D1; the enable resistor R2 and the enable capacitor One end of C2 connected in parallel is connected to the gate of the thyristor T1, and the other end of the enable resistor R2 and the enable capacitor C2 connected in parallel is connected to the positive electrode of the output diode D3; the negative electrode of the output diode D3 is used to connect the voltage bus VBUS of the motor; the power-off discharge circuit 12 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a normally closed relay U1; the normally closed relay U1 includes a first control terminal LED+, a second control terminal LED-, a first output terminal OUT1 and a second output terminal OUT2; the power input terminal DCIN+ is connected to the first control terminal LED+ through the third resistor R3; the second control terminal LED- is connected to the ground terminal DGND; one end of the fourth resistor R4 is connected to the first output terminal OUT1, and the other end of the fourth resistor R4 is connected to the negative electrode of the output diode D3; one end of the fifth resistor R5 is connected to the second output terminal OUT2, and the other end of the fifth resistor R5 is connected to the ground terminal DGND.

[0031] The present embodiment provides a circuit for suppressing motor reversal, including two modules, a delayed power-on circuit 11 and a power-off discharge circuit 12, which can provide two functions of delayed motor power-on and suppression of motor reversal. The working principle of delayed motor power-on is as follows: when a DC voltage source supplies power to the power input terminal DCIN+, the first control terminal LED+ of the normally closed relay U1 is energized, the first control terminal LED+ and the second control terminal LED- are disconnected, and the first output terminal OUT1 and the second output terminal OUT2 are also disconnected; the DC voltage source charges the charging capacitor C1 through the power input terminal DCIN+ and the charging resistor R1, and the charging time can be adjusted by adjusting the size of the charging resistor R1 and the charging capacitor C1, thereby adjusting the delay time of the motor delayed power-on; after the charging capacitor C1 is charged to a certain voltage value, the voltage regulator diode D2 is reversely conducted to provide an enabling voltage to the gate of the thyristor T1; the thyristor T1 After being turned on, the DC voltage source charges the enable resistor R2 and the enable capacitor C2 through the power input terminal DCIN+ and the thyristor T1, the thyristor T1 remains in the on state, the voltage zener diode D2 is forward-conducted, and the DC voltage source supplies power to the voltage bus VBUS of the motor through the power input terminal DCIN+, the thyristor T1 and the output diode D3. The voltage bus VBUS of the motor supplies power to the motor through the drive circuit. After the motor rotates forward, the Stirling rotary refrigerator or other equipment containing the motor can work normally. By delaying the power-on of the motor, it can be avoided that the normally closed relay U1 is not disconnected in time when the motor is powered on, causing the voltage bus VBUS to be connected to the ground terminal DGND, resulting in the motor not being able to operate normally. The working principle of suppressing motor reversal is as follows: when the DC voltage source stops supplying power to the power input terminal DCIN+, the first control terminal LED+ of the normally closed relay U1 loses power, the first control terminal LED+ and the second control terminal LED- are connected, and the first output terminal OUT1 and the second output terminal OUT2 are also connected; the charging capacitor C1 releases the remaining potential energy through the discharge diode D1, the third resistor R3, the first output terminal OUT1, the second control terminal LED- and the ground terminal DGND; the enabling capacitor C2 releases the remaining potential energy through the enabling resistor R2; the reverse electromotive force generated by the motor reversal is released through the motor's voltage bus VBUS, the fourth resistor R4, the first output terminal OUT1, the second output terminal OUT2, the fifth resistor R5 and the ground terminal DGND, thereby suppressing the motor reversal. If the reverse electromotive force generated by the motor reversal is small, this circuit can prevent the motor from reversing.

[0032] Preferably, Figure 3 As shown, the normally closed relay U1 is a normally closed optocoupler relay. The normally closed optocoupler relay has no mechanical contacts, has a long service life, and operates stably, and can be used in a circuit for suppressing motor reversal provided by the present invention. In other embodiments, the normally closed relay U1 can be a normally closed mechanical relay or other types of relays.

[0033] Preferably, Figure 3 As shown, the charging resistor R1 is an adjustable resistor. The resistance value of the adjustable resistor can be adjusted at any time, thereby adjusting the charging time of the charging capacitor C1. In other embodiments, the charging resistor R1 can be a fixed resistor.

[0034] Preferably, Figure 3 As shown, the charging capacitor C1 is an adjustable capacitor. The capacitance of the adjustable capacitor can be adjusted at any time, thereby adjusting the charging time of the charging capacitor C1. In other embodiments, the charging capacitor C1 can be a fixed capacitor.

[0035] Preferably, Figure 3 As shown, the enabling resistor R2 is an adjustable resistor. If the resistance of the enabling resistor R2 can be adjusted at any time, the discharge speed of the enabling capacitor C2 can be adjusted. In other embodiments, the enabling resistor R2 can be a fixed resistor.

[0036] Preferably, Figure 3 As shown, the enabling capacitor C2 is an adjustable capacitor. If the capacitance of the enabling capacitor C2 can be adjusted at any time, it can be adapted to different types of thyristors T1. In other embodiments, the enabling capacitor C2 can be a fixed capacitor.

[0037] Preferably, Figure 3 As shown, the third resistor R3 is an adjustable resistor. If the resistance of the third resistor R3 can be adjusted at any time, the discharge speed of the charging capacitor C1 can be adjusted. In other embodiments, the third resistor R3 can be a fixed resistor.

[0038] Preferably, Figure 3 As shown, the fourth resistor R4 is an adjustable resistor. If the resistance of the fourth resistor R4 can be adjusted at any time, the discharge speed of the reverse electromotive force generated by the motor reverse power generation can be adjusted. In other embodiments, the fourth resistor R4 can be a fixed resistor.

[0039] Preferably, the discharge diode D1 is a high-speed diode. A high-speed diode has a very fast switching speed and can be used in a circuit for suppressing motor reversal provided by the present invention. In other embodiments, the discharge diode D1 can be a conventional diode.

[0040] Preferably, Figure 3 As shown, the output diode D3 is a Schottky diode. The Schottky diode has a low forward voltage drop and a fast switching speed, and can be used in a circuit for suppressing motor reversal provided by the present invention. In other embodiments, the output diode D3 can be a conventional diode.

[0041] In summary, the present invention provides a circuit for suppressing motor reversal, including two modules, a delayed power-on circuit 11 and a power-off discharge circuit 12, which can provide two functions of delayed motor power-on and suppression of motor reversal. The working principle of delayed motor power-on is as follows: when a DC voltage source supplies power to the power input terminal DCIN+, the first control terminal LED+ of the normally closed relay U1 is energized, the first control terminal LED+ and the second control terminal LED- are disconnected, and the first output terminal OUT1 and the second output terminal OUT2 are also disconnected; the DC voltage source charges the charging capacitor C1 through the power input terminal DCIN+ and the charging resistor R1, and the charging time can be adjusted by adjusting the size of the charging resistor R1 and the charging capacitor C1, thereby adjusting the delay time of the motor delayed power-on; after the charging capacitor C1 is charged to a certain voltage value, the voltage regulator diode D2 is reversely conducted to provide an enabling voltage to the gate of the thyristor T1; the thyristor T1 After being turned on, the DC voltage source charges the enable resistor R2 and the enable capacitor C2 through the power input terminal DCIN+ and the thyristor T1, the thyristor T1 remains in the on state, the voltage zener diode D2 is forward-conducted, and the DC voltage source supplies power to the voltage bus VBUS of the motor through the power input terminal DCIN+, the thyristor T1 and the output diode D3. The voltage bus VBUS of the motor supplies power to the motor through the drive circuit. After the motor rotates forward, the Stirling rotary refrigerator or other equipment containing the motor can work normally. By delaying the power-on of the motor, it can be avoided that the normally closed relay U1 is not disconnected in time when the motor is powered on, causing the voltage bus VBUS to be connected to the ground terminal DGND, resulting in the motor not being able to operate normally. The working principle of suppressing motor reversal is as follows: when the DC voltage source stops supplying power to the power input terminal DCIN+, the first control terminal LED+ of the normally closed relay U1 loses power, the first control terminal LED+ and the second control terminal LED- are connected, and the first output terminal OUT1 and the second output terminal OUT2 are also connected; the charging capacitor C1 releases the remaining potential energy through the discharge diode D1, the third resistor R3, the first output terminal OUT1, the second control terminal LED- and the ground terminal DGND; the enabling capacitor C2 releases the remaining potential energy through the enabling resistor R2; the reverse electromotive force generated by the motor reversal is released through the motor's voltage bus VBUS, the fourth resistor R4, the first output terminal OUT1, the second output terminal OUT2, the fifth resistor R5 and the ground terminal DGND, thereby suppressing the motor reversal. If the reverse electromotive force generated by the motor reversal is small, this circuit can prevent the motor from reversing.

[0042] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art based on the above disclosure shall fall within the protection scope of the present invention.

Claims

1. A circuit for suppressing motor reverse rotation, characterized in that: Including a delayed power-on circuit and a power-off discharge circuit; The delayed power-on circuit includes a power input terminal, a discharge diode, a charging capacitor, a charging resistor, a thyristor, a voltage regulator diode, an enable resistor, an enable capacitor and an output diode; the power input terminal is connected to the cathode of the discharge diode, the anode of the discharge diode is connected to one end of the charging capacitor; the other end of the charging capacitor is connected to the ground terminal; the charging resistor and the discharge diode are connected in parallel; The anode of the thyristor is connected to the power input terminal, the cathode of the thyristor is connected to the positive electrode of the output diode, the gate of the thyristor is connected to the positive electrode of the voltage regulator diode; the negative electrode of the voltage regulator diode is connected to the positive electrode of the discharge diode; one end of the enable resistor and the enable capacitor connected in parallel is connected to the gate of the thyristor, and the other end of the enable resistor and the enable capacitor connected in parallel is connected to the positive electrode of the output diode; the negative electrode of the output diode is used to connect to the voltage bus of the motor; The power-off discharge circuit includes a third resistor, a fourth resistor, a fifth resistor and a normally closed relay; the normally closed relay includes a first control end, a second control end, a first output end and a second output end; the power input end is connected to the first control end through the third resistor; the second control end is connected to the ground end; one end of the fourth resistor is connected to the first output end, and the other end of the fourth resistor is connected to the negative electrode of the output diode; one end of the fifth resistor is connected to the second output end, and the other end of the fifth resistor is connected to the ground end.

2. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The normally closed relay is a normally closed optocoupler relay.

3. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The charging resistor is an adjustable resistor.

4. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The charging capacitor is an adjustable capacitor.

5. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The enabling resistor is an adjustable resistor.

6. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The enabling capacitor is an adjustable capacitor.

7. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The third resistor is an adjustable resistor.

8. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The fourth resistor is an adjustable resistor.

9. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The discharge diode is a high-speed diode.

10. A circuit for suppressing motor reverse rotation as claimed in claim 1, characterized in that: The output diode is a Schottky diode.

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