An electro-permanent magnet magnetization and demagnetization control circuit and its control method
Through a single signal loop control circuit, the charging and demagnetization of the electric permanent magnet is stabilized by using components such as op amps and field effect tubes, solving the problems of complex lines and magnetic field interference in the existing technology, and achieving more efficient magnet combination control.
Patent Information
- Application Number
- CN202510653133.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-21
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2045-05-21
AI Technical Summary
In the existing electric permanent magnet charging and demagnetization control method, the magnetic charging and demagnetization circuit are opposite, resulting in increased line complexity and interference from external magnetic field, and there is magnetization transition or residual magnetism.
A single-signal loop control circuit is adopted, and through components such as op amps, field effect tubes, solid-state relays, etc., combined with variable capacitors and digital potentiometers, stable control of charging and demagnetization is achieved, and external magnetic field interference is avoided by open-circuit charging and magnetization.
Add the controllable number of magnet combinations under the same resource port, stabilize the stop-control mechanism, avoid magnetization transition and external magnetic field interference, and improve control accuracy.
Smart Images
Figure CN120183844B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electro-permanent magnetism, and particularly relates to an electro-permanent magnet charging and demagnetizing control circuit and a control method thereof. Background Art
[0002] CN118448125A discloses an electro-permanent magnet charging and demagnetizing device and a charging and demagnetizing method thereof, which can control the on-off of each control switch through a controller to realize the charging and demagnetizing of multiple electro-permanent magnets. However, the problem with this method is that since the charging and demagnetizing circuits are opposite, the charging and demagnetizing coils of each magnet have to be controlled by two independent signal circuits, which will increase the circuit complexity in the combined control process and the port occupation of the upper controller. Another problem is that since the charging method is open-circuit charging, the external magnetic field has a greater impact on detection, and phenomena such as magnetization transition or remanence will occur when reaching the detection critical point. Summary of the Invention
[0003] Aiming at the above technical problems, the object of the present invention is to provide an electro-permanent magnet charging and demagnetizing control circuit, including several operational amplifiers, several diodes, several field effect transistors, several resistors, an AND gate, a digital potentiometer, a switch, a solid state relay, and an inverter;
[0004] The non-inverting input terminal of operational amplifier U1 among the several operational amplifiers is connected to one end of resistor R2, the inverting input terminal is connected to reference signal Vref_1, and the output terminal is connected to the magnetization auxiliary control signal Port_1; the inverting input terminal of operational amplifier U2 is connected to one end of resistor R4, one end of resistor R11, one end of capacitor C2, and the non-inverting input terminal of operational amplifier U5, and the output terminal is connected to the first input terminal of AND gate U4; the input terminal of inverter U3 is connected to one end of resistor R5 and one end of the coil of solid-state relay K1, and the output terminal is connected to the source electrode of field-effect transistor Q2; the second input terminal of AND gate U4 is connected to the output terminal of operational amplifier U5, and the output terminal is connected to the anode of diode D1 and the base of triode Q3; the first pin of digital potentiometer U6 is connected to the collector of triode Q3 and one end of resistor R15, the second pin and the sixth pin are connected to the anode of diode D2, the third pin is connected to the cathode of diode D3 and the cathode of diode D4, the fourth pin is connected to the cathode of diode D1, the cathode of diode D2, and one end of resistor R10, and the fifth pin is connected to the common terminal of solid-state relay K1; the non-inverting input terminal of operational amplifier U7 is connected to one end of resistor R13, the inverting input terminal is connected to reference signal Vref_1, and the output terminal is connected to the demagnetization auxiliary control signal Port_2; the gate of field-effect transistor Q1 is connected to the first connection end of solid-state relay K1, the drain is connected to the other end of resistor R2 and the magnetization main control signal Port_3, and the source is connected to the other end of resistor R4, the other end of resistor R5, and one end of switch S1; the gate of field-effect transistor Q2 is connected to the second connection end of solid-state relay K1, and the drain is connected to the other end of resistor R13 and the demagnetization main control signal Port_4; the anode of diode D3 is connected to the magnetization auxiliary control signal Port_1; the anode of diode D4 is connected to the demagnetization auxiliary control signal Port_2; the other end of switch S1 and the other end of resistor R15 are connected to the power supply; the other end of resistor R10, the other end of resistor R11, the other end of the coil of solid-state relay K1, the other end of capacitor C2, the emitter of triode Q3 are connected to the ground terminal.
[0005] Further, it further includes several variable capacitors; the several variable capacitors include variable capacitor C1 and variable capacitor C3; the several resistors further include resistor R6 and resistor R14; one end of resistor R6 among the several resistors is connected to one end of variable capacitor C1 and the non-inverting input terminal of operational amplifier U1; one end of resistor R14 is connected to one end of variable capacitor C3 and the non-inverting input terminal of operational amplifier U7; the other end of resistor R6, the other end of resistor R14, the other end of variable capacitor C1, and the other end of variable capacitor C3 are connected to the ground terminal.
[0006] Further, the several resistors further include resistor R3, resistor R9, and resistor R12; one end of resistor R3 among the several resistors is connected to the power supply; one end of resistor R9 is connected to the other end of resistor R3 and the non-inverting input terminal of operational amplifier U2, and the other end is connected to one end of resistor R12 and the inverting input terminal of operational amplifier U5; the other end of resistor R12 is connected to the ground terminal.
[0007] Furthermore, the plurality of resistors further include a resistor R1 and a resistor R7; one end of the resistor R1 among the plurality of resistors is connected to the power supply, and the other end is connected to one end of the resistor R7 and a reference signal Vref_1; the other end of the resistor R7 is connected to the ground.
[0008] Furthermore, a resistor R8 is connected in series between the common terminal and the ground terminal of the solid-state relay K1.
[0009] Furthermore, the resistor R2 and the resistor R13 are adjustable resistors.
[0010] Furthermore, a method for controlling the charging and demagnetization of an electro-permanent magnet comprises the following steps:
[0011] S1. Set magnetization and demagnetization parameters;
[0012] S2. Detect the charging and demagnetization signals and generate corresponding pre-magnetization and demagnetization signals;
[0013] S3. After the demagnetization signal is started, the corresponding master control signal is sent to magnetize or demagnetize, and the magnetization and demagnetization are stopped after the parameters are reached;
[0014] S4. After the charging and demagnetization signal changes and passes the preceding signal, the stop control is released and reset to the initial state.
[0015] The beneficial effects of the present invention compared with the prior art are:
[0016] The present invention can complete the charging and demagnetization control through a single signal loop, increase the number of controllable magnet combinations under the same resource port, and the stop control mechanism is stable, which can avoid the problem of instantaneous re-charging and demagnetization caused by the interference of the external magnetic field after open-circuit magnetization. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the prior art and the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0018] Figure 1 The circuit structure diagram provided by the present invention. DETAILED DESCRIPTION
[0019] In order to make the objects and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific implementations of the present invention, and does not strictly limit the scope of protection specifically requested by the present invention.
[0020] The present invention discloses a control circuit for charging and demagnetizing an electro-permanent magnet, which includes several operational amplifiers, several diodes, several field effect transistors, several resistors, an AND gate, a digital potentiometer, a switch, a solid state relay, and an inverter; the several operational amplifiers include operational amplifier U1, operational amplifier U2, operational amplifier U5, and operational amplifier U7; the several diodes include diode D1, diode D2, diode D3, and diode D4; the several field effect transistors include field effect transistor Q1 and field effect transistor Q2; the several resistors include resistor R2, resistor R4, resistor R5, resistor R10, resistor R11, resistor R13, and resistor R15;
[0021] The non-inverting input terminal of operational amplifier U1 in the several operational amplifiers is connected to one end of resistor R2, the inverting input terminal is connected to the reference signal Vref_1, and the output terminal is connected to the auxiliary magnetization control signal Port_1; the inverting input terminal of operational amplifier U2 is connected to one end of resistor R4, one end of resistor R11, one end of capacitor C2, and the non-inverting input terminal of operational amplifier U5, and the output terminal is connected to the first input terminal of AND gate U4; the input terminal of inverter U3 is connected to one end of resistor R5 and one end of the coil of solid state relay K1, and the output terminal is connected to the source electrode of field effect transistor Q2; the second input terminal of AND gate U4 is connected to the output terminal of operational amplifier U5, and the output terminal is connected to the anode of diode D1 and the base of triode Q3; the first pin of digital potentiometer U6 is connected to the collector of triode Q3 and one end of resistor R15, the second pin and the sixth pin are connected to the anode of diode D2, the third pin is connected to the cathode of diode D3 and the cathode of diode D4, the fourth pin is connected to the cathode of diode D1, the cathode of diode D2, and one end of resistor R10, the fifth pin is connected to the common terminal of solid state relay K1; the non-inverting input terminal of operational amplifier U7 is connected to one end of resistor R13, the inverting input terminal is connected to the reference signal Vref_1, and the output terminal is connected to the demagnetization auxiliary control signal Port_2; the gate of field effect transistor Q1 is connected to the first connection terminal of solid state relay K1, the drain is connected to the other end of resistor R2 and the main magnetization control signal Port_3, and the source is connected to the other end of resistor R4, the other end of resistor R5, and one end of switch S1; the gate of field effect transistor Q2 is connected to the second connection terminal of solid state relay K1, the drain is connected to the other end of resistor R13 and the main demagnetization control signal Port_4; the anode of diode D3 is connected to the auxiliary magnetization control signal Port_1; the anode of diode D4 is connected to the demagnetization auxiliary control signal Port_2; the other end of switch S1, the other end of resistor R15 are connected to the power supply; the other end of resistor R10, the other end of resistor R11, the other end of the coil of solid state relay K1, the other end of capacitor C2, the emitter of triode Q3 are connected to the ground terminal.
[0022] Specifically, it further includes several variable capacitors, the several variable capacitors include variable capacitor C1 and variable capacitor C3; the several resistors further include resistor R6 and resistor R14;
[0023] One end of the resistor R6 among the plurality of resistors is connected to one end of the variable capacitor C1 and the in-phase end of the operational amplifier U1; one end of the resistor R14 is connected to one end of the variable capacitor C3 and the in-phase end of the operational amplifier U7; the other end of the resistor R6, the other end of the resistor R14, the other end of the variable capacitor C1, the other end of the variable capacitor C3 and the ground are connected.
[0024] Specifically, the plurality of resistors further include a resistor R3, a resistor R9 and a resistor R12;
[0025] One end of the resistor R3 among the plurality of resistors is connected to the power supply; one end of the resistor R9 is connected to the other end of the resistor R3 and the in-phase end of the operational amplifier U2, and the other end is connected to one end of the resistor R12 and the inverting end of the operational amplifier U5; the other end of the resistor R12 is connected to the ground.
[0026] Specifically, the plurality of resistors further include a resistor R1 and a resistor R7;
[0027] One end of the resistor R1 among the plurality of resistors is connected to the power supply, and the other end is connected to one end of the resistor R7 and the reference signal Vref_1; the other end of the resistor R7 is connected to the ground.
[0028] Specifically, a resistor R8 is connected in series between the common terminal and the ground terminal of the solid-state relay K1.
[0029] Specifically, the resistor R2 and the resistor R13 are adjustable resistors.
[0030] The present invention also provides a method for controlling the charging and demagnetization of an electro-permanent magnet, comprising the following steps:
[0031] S1. Set magnetization and demagnetization parameters;
[0032] S2. Detect the charging and demagnetization signals and generate corresponding pre-magnetization and demagnetization signals;
[0033] S3. After the demagnetization signal is started, the corresponding master control signal is sent to magnetize or demagnetize, and the magnetization and demagnetization are stopped after the parameters are reached;
[0034] S4. After the charging and demagnetization signal changes and passes the preceding signal, the stop control is released and reset to the initial state.
[0035] Specifically, Port_1 is the magnetization auxiliary control signal, Port_2 is the demagnetization auxiliary control signal, Port_3 is the magnetization main control signal, Port_4 is the demagnetization main control signal, Vref_1 is the reference signal, the variable capacitor C1 and the variable capacitor C3 are used to adjust the magnetization and demagnetization parameters, the Port_3 and Prot_4 signals are connected to the switch circuit (not shown in the attached figure, the closing of the main contact is controlled by the contactor coil), S1 is a switch for simulating the generation of the magnetization and demagnetization signals, and in the scheme, when S1 has a signal (switching between closed and open states), a fixed period pre-signal is generated that is not controlled by the continuous period of the S1 signal, in order to form a single signal circuit for magnetization and demagnetization, and the S1 signal is detected by the operational amplifier U2 and the operational amplifier U5. Resistors R3, R9 and R12 set the duration of the preamplifier signal. The signal flow is that after S1 is closed, the signal at the connection end of S1 and resistor R4 is fed back to capacitor C2 for integration and pull-up of the correspondingly connected op amp U2 inverting terminal and op amp U5 in-phase terminal voltage, and capacitor C2 is pulled up. After the initial power-on and when S1 is off, the output of op amp U2 is output, and the output of op amp U5 is cut off. When the voltage at capacitor C2 is pulled up to the inverting terminal voltage of op amp U5, the output of op amp U5 is output. The output signals of op amp U2 and op amp U5 are fed back to AND gate U4. After there are signals at both input terminals of AND gate U4, AND gate U4 outputs a signal to the base of transistor Q3, and transistor Q3 is turned on. The power signal passes through resistor R15, collector and emitter of transistor Q3. The fifth pin of the digital potentiometer U6 will be set to zero. When the voltage at the capacitor C2 end is pulled up to the voltage at the in-phase end of the operational amplifier U2, the operational amplifier U2 is cut off, the base of the transistor Q3 has no input and is reset. When S1 changes from a closed state to an off state, the capacitor C2 will be connected to the ground loop through the resistor R11, and the voltage at the capacitor C2 end will be pulled down. The above process will be repeated and become the initial power-on state. At the same time, when S1 is closed, the signal will be input to the source of the field effect tube Q1, one way to the input end of the inverter U3 through the resistor R5, and one way to the coil of the solid-state relay K1 through the resistor R5. The inverter U3 inverts the signal and inputs it to the source of the field effect tube Q2. At this time, the solid-state relay K1 will be turned on, and the auxiliary contact will be switched to the gate of the field effect tube Q1. S1 switches from closed to closed or closed to closed, and the fifth pin of the digital potentiometer U6 is set to zero. At this time, the sixth pin will output a signal. In addition to being fed back to the gate of the field effect tube Q1 through the auxiliary contact of the solid-state relay K1, the signal will also be input to the fourth pin through the diode D2. The gate of the field effect tube Q1 is turned on after the signal exists, and its power supply is fed back to the variable capacitor C1 through S1, the source and drain of the field effect tube Q1, and the resistor R2, and is input to the operational amplifier U1 for detection. As the field effect tube Q1 is turned on, the voltage at the in-phase terminal of the operational amplifier U1 is gradually pulled up to the reference signal voltage set at its inverting terminal. The output signal of the operational amplifier U1 will be fed back to the third pin of the digital potentiometer U6 through the diode D3, and the digital potentiometer U6 will switch the current setting state.The sixth pin of the digital potentiometer U6 is cut off. The fifth pin will output a signal that passes through the auxiliary contact of the solid-state relay K1 to the gate of the field-effect transistor Q1. The field-effect transistor Q1 is cut off. The variable capacitor C1 first passes through the resistor R6 circuit, and the operational amplifier U1 is cut off. At this time, the voltage at the connection end of the drain of the field-effect transistor Q1 and the resistor R2 drops. When S1 is still closed, magnetization stopping control is performed. And due to the cut-off of the AND gate U4 after the input of the pre-signal, there is no input to the diode D1. When the sixth pin of the digital potentiometer U6 is cut off, the cut-off of the diode D2 will make the fourth pin of the digital potentiometer U6 in a state of no input. This state will be maintained until a pre-signal is provided after S1 is disconnected (during demagnetization), and then a set switching is provided again. When the voltage of the variable capacitor C1 approaches the Vref_1 critical point, the repeated output of the operational amplifier U1 caused by the voltage fluctuation of the variable capacitor C1 due to external interference will not disconnect the output of the fifth pin of the digital potentiometer U6, so as to avoid excessive magnetization. At the same time, since there are only the number of times of recovery switching when there is a pre-signal, it will not detect fluctuations after open-circuit magnetization to cause misalignment of the outputs of the fifth and sixth pins of the digital potentiometer U6, resulting in the problem of recharging and demagnetization. When S1 is turned off, the digital potentiometer U6 obtains a pre-signal again. At the same time, the S1 signal is inverted by the inverter U3, and the inverted signal is input to the variable capacitor C3 through the source, drain, and resistor R13 of the field-effect transistor Q2. The non-inverting terminal of the operational amplifier U7 is detecting. At the same time, the auxiliary contact of the solid-state relay K1 is reset (in the state of the attached drawing). When the voltage of the variable capacitor C3 reaches Vref_1, the operational amplifier U7 is input to the third pin of the digital potentiometer U6 through the diode D4. The signal output from the fifth pin of the digital potentiometer U6 makes the field-effect transistor Q2 cut off through the solid-state relay K1. The voltage at the connection end of the drain of the field-effect transistor Q2 and the resistor R13 drops, and demagnetization stops in the state where S1 is still disconnected. And the signal output of the controller to S1 can only be determined by 1 / 0 to determine the current required enabling state of the circuit.
[0036] The resistor R2 and the variable capacitor C1 are used to adjust the corresponding magnetization time constant. The resistor R13 and the variable capacitor C3 are used to adjust the corresponding demagnetization time constant. The resistor R8 is selected and set according to the charge-discharge interval. When the interval is short, it is set to avoid parasitic oscillation caused by incomplete discharge. The reference signals at the inverting terminals of the operational amplifier U1 and the operational amplifier U7 can also be set with different voltage parameters to increase the fault tolerance probability. The Vref_1 reference signal and the reference signals of other operational amplifiers can also be set through the upper-level circuit or power supply in addition to resistor voltage division. The switching circuit can also increase the amplification circuit to amplify the signals of Port_3 and Port_4 according to the contactor coil voltage.
[0037] It is obvious to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claim concerned.
Claims
1. An electro-permanent magnet magnetization and demagnetization control circuit, characterized in that, It includes several operational amplifiers, several diodes, several field effect transistors, several resistors, an AND gate, a digital potentiometer, a switch, a solid state relay, and an inverter; The non-inverting input terminal of operational amplifier U1 among the several operational amplifiers is connected to one end of resistor R2, the inverting input terminal is connected to the reference signal Vref_1, and the output terminal is connected to the magnetization assisting control signal Port_1; The inverting input terminal of operational amplifier U2 is connected to one end of resistor R4, one end of resistor R11, one end of capacitor C2, and the non-inverting input terminal of operational amplifier U5, and the output terminal is connected to the first input terminal of AND gate U4; The input terminal of inverter U3 is connected to one end of resistor R5 and one end of the coil of solid state relay K1, and the output terminal is connected to the source electrode of field effect transistor Q2; The second input terminal of AND gate U4 is connected to the output terminal of operational amplifier U5, and the output terminal is connected to the anode of diode D1 and the base of triode Q3; The first pin of digital potentiometer U6 is connected to the collector of triode Q3 and one end of resistor R15, the second pin and the sixth pin are connected to the anode of diode D2, the third pin is connected to the cathode of diode D3 and the cathode of diode D4, the fourth pin is connected to the cathode of diode D1, the cathode of diode D2, and one end of resistor R10, and the fifth pin is connected to the common terminal of solid state relay K1; The non-inverting input terminal of operational amplifier U7 is connected to one end of resistor R13, the inverting input terminal is connected to the reference signal Vref_1, and the output terminal is connected to the demagnetization assisting control signal Port_2; The gate electrode of field effect transistor Q1 is connected to the first connection terminal of solid state relay K1, the drain electrode is connected to the other end of resistor R2 and the magnetization main control signal Port_3, and the source electrode is connected to the other end of resistor R4, the other end of resistor R5, and one end of switch S1; The gate electrode of field effect transistor Q2 is connected to the second connection terminal of solid state relay K1, the drain electrode is connected to the other end of resistor R13 and the demagnetization main control signal Port_4; The anode of diode D3 is connected to the magnetization assisting control signal Port_1; The anode of diode D4 is connected to the demagnetization assisting control signal Port_2; The other end of switch S1 and the other end of resistor R15 are connected to the power supply; The other end of resistor R10, the other end of resistor R11, the other end of the coil of solid state relay K1, the other end of capacitor C2, the emitter of triode Q3 are connected to the ground terminal.
2. The demagnetization control circuit of the electro-permanent magnet according to claim 1, wherein It further includes several variable capacitors, and the several variable capacitors include variable capacitor C1 and variable capacitor C3; The several resistors further include resistor R6 and resistor R14; One end of resistor R6 is connected to one end of variable capacitor C1 and the non-inverting input terminal of operational amplifier U1; One end of resistor R14 is connected to one end of variable capacitor C3 and the non-inverting input terminal of operational amplifier U7; The other end of resistor R6, the other end of resistor R14, the other end of variable capacitor C1, and the other end of variable capacitor C3 are connected to the ground terminal.
3. The electro-permanent magnet magnetization and demagnetization control circuit according to claim 1, characterized in that, The several resistors further include resistor R3, resistor R9, and resistor R12; One end of resistor R3 is connected to the power supply; One end of resistor R9 is connected to the other end of resistor R3 and the non-inverting input terminal of operational amplifier U2, and the other end is connected to one end of resistor R12 and the inverting input terminal of operational amplifier U5; The other end of resistor R12 is connected to the ground terminal.
4. The demagnetization control circuit of the electro-permanent magnet according to claim 1, characterized in that, The plurality of resistors further include a resistor R1 and a resistor R7; one end of the resistor R1 is connected to a power source, and the other end is connected to one end of the resistor R7 and a reference signal Vref_1; the other end of the resistor R7 is connected to the ground.
5. The demagnetization control circuit of the electro-permanent magnet according to claim 1, characterized in that, A resistor R8 is connected in series between the common terminal and the ground terminal of the solid-state relay K1.
6. The demagnetization control circuit of the electro-permanent magnet according to claim 1, wherein The resistor R2 and the resistor R13 are adjustable resistors.
7. A method for controlling magnetization and demagnetization of an electro-permanent magnet to implement an electro-permanent magnet magnetization and demagnetization control circuit according to any one of claims 1-6, characterized in that, The following steps are included: S1. Set magnetization and demagnetization parameters; S2. Detect the charging and demagnetization signals and generate corresponding pre-magnetization and demagnetization signals; S3. After the demagnetization signal is started, the corresponding master control signal is sent to magnetize or demagnetize, and the magnetization and demagnetization are stopped after the parameters are reached; S4. After the charging and demagnetization signal changes and passes the preceding signal, the stop control is released and reset to the initial state.
Citation Information
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