A ripple signal acquisition circuit after motor stop

Abstract

The application relates to a ripple signal acquisition circuit after motor stop, and relates to the technical field of motor circuits; the application comprises an external power supply, a controller, a first motor driving module, a second motor driving module, a first motor control module, a second motor control module, a first current detection module and a second current detection module; the voltage output end of the external power supply is electrically connected to the power supply ends of the first and second motor driving modules, and the output ends of the first and second motor driving modules are electrically connected to the 1st pin and the 2nd pin of the motor; the first and second motor driving modules are controlled and connected to the first and second motor control modules; the sampling ends of the first and second motor driving modules are electrically connected to the input ends of the first and second current detection modules, and the output ends of the first and second current detection modules are electrically connected to the input end of the controller. The application has the effect of solving the technical problem that the ripple signal cannot be effectively detected after the stop of a traditional motor control system.

Description

Technical Field

[0001] This application relates to the technical field of motor circuits, and in particular to a ripple signal acquisition circuit after a motor stops. Background Technology

[0002] In motor control systems, ripple signal detection is crucial for system status monitoring and fault diagnosis. As an AC component superimposed on a DC signal, the ripple signal's characteristics directly reflect the system's operating state. Ripple signals can originate from various sources: high-frequency switching noise from the power converter, induced voltage generated by the motor winding inductance and commutation process, transient responses during power device switching, and coupling interference from the external electromagnetic environment. Analyzing the amplitude, frequency, and other characteristics of the ripple signal can effectively assess power quality, filter circuit performance, and the stability of the entire drive system, providing important data for system optimization and fault early warning.

[0003] However, traditional motor drive circuits have significant limitations in signal detection capabilities when the motor is stopped. When the control signal cuts off the motor, the conventional current detection circuit often disconnects, causing the system to be unable to obtain important status information during the motor's shutdown process. Utility Model Content

[0004] To address the technical challenge of effectively detecting ripple signals after a motor stops in traditional motor control systems, this application provides a ripple signal acquisition circuit after the motor stops.

[0005] The ripple signal acquisition circuit after a motor stops provided in this application adopts the following technical solution:

[0006] 1. A ripple signal acquisition circuit after a motor stops, comprising:

[0007] The system includes a controller, a first motor control module, a second motor control module, a first current detection module, and a second current detection module; both the first motor control module and the second motor control module are controlled and connected to the controller, and the output terminals of the first current detection module and the second current detection module are electrically connected to the input terminal of the controller.

[0008] The first motor drive module includes a relay K1. The voltage output terminal of the external power supply is electrically connected to pin 2 of the relay K1, and pin 1 of the relay K1 is controlled to be connected to the first motor control module. Pin 1 of the motor is electrically connected to the common terminal pin 3 of the relay K1. The normally open terminal pin 5 of the relay K1 is electrically connected to the voltage output terminal of the external power supply, and the normally closed terminal pin 4 of the relay K1 is electrically connected to the input terminal of the first current detection module.

[0009] The second motor drive module includes a relay K2. The voltage output terminal of the external power supply is electrically connected to pin 2 of the relay K2, and pin 1 of the relay K2 is controlled to be connected to the second motor control module. Pin 2 of the motor is electrically connected to the common terminal pin 3 of the relay K2. The normally open terminal pin 5 of the relay K2 is electrically connected to the voltage output terminal of the external power supply, and the normally closed terminal pin 4 of the relay K2 is electrically connected to the input terminal of the second current detection module.

[0010] By adopting the above technical solution, a complete ripple signal acquisition system architecture after motor stop was constructed. Through the cooperation of dual relay drive and dual current detection modules, the full-cycle current signal detection in both motor running and stopping states was realized, solving the technical problem that traditional circuits cannot detect ripple signals after shutdown.

[0011] Preferably, the first motor control module includes a transistor Q1, a voltage divider resistor R1, and a voltage divider resistor R2. The first control output terminal of the controller is electrically connected to the base of the transistor Q1 through the voltage divider resistors R1 and R2. The emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is electrically connected to pin 1 of the relay K1.

[0012] By adopting the above technical solution, when the first control terminal of the controller outputs a high level, transistor Q1 is turned on, relay K1 is energized, and the motor rotates in the forward direction; when the first control terminal of the controller outputs a low level, transistor Q1 is turned off.

[0013] Preferably, the second motor control module includes a transistor Q2, a voltage divider resistor R3, and a voltage divider resistor R4. The second control output terminal of the controller is electrically connected to the base of the transistor Q2 through the voltage divider resistors R3 and R4. The emitter of the transistor Q2 is grounded, and the collector of the transistor Q2 is electrically connected to pin 1 of the relay K2.

[0014] By adopting the above technical solution, when the second control terminal of the controller outputs a high level, transistor Q2 is turned on, relay K2 is energized, and the motor reverses; when the second control terminal of the controller outputs a low level, transistor Q2 is turned off.

[0015] Preferably, the first current detection module includes an operational amplifier U1, a sampling resistor R5, and a feedback resistor R10; one end of the sampling resistor R5 is electrically connected to the normally closed terminal 4 of the relay K1, and the other end of the sampling resistor R5 is grounded; the non-inverting input terminal of the operational amplifier U1 is electrically connected to the normally closed terminal 4 of the relay K1 through a resistor R6, the inverting input terminal of the operational amplifier U1 is grounded through a resistor R7, the output terminal of the operational amplifier U1 is electrically connected to the inverting input terminal of the operational amplifier U1 through a feedback resistor R10, and the output terminal of the operational amplifier U1 is electrically connected to the first input terminal of the controller.

[0016] By adopting the above technical solution, the current output from the normally closed terminal 4 of relay K1 is differentially amplified through operational amplifier U1 and peripheral components, ensuring accurate acquisition of reverse current and ripple signal after shutdown.

[0017] Preferably, the first current detection module further includes a power supply V1, a resistor R8, and a resistor R9. The voltage output terminal of the power supply V1 is grounded in sequence through resistors R8 and R9, and the connection point between resistors R8 and R9 is electrically connected to the non-inverting input terminal of the operational amplifier U1.

[0018] By adopting the above technical solution, a DC bias is provided to the non-inverting input of the operational amplifier U1, avoiding distortion of the negative ripple signal when powered by a single power supply and ensuring full waveform acquisition.

[0019] Preferably, the second current detection module includes an operational amplifier U2, a sampling resistor R12, and a feedback resistor R17; one end of the sampling resistor R12 is electrically connected to the normally closed terminal 4 of the relay K2, and the other end of the sampling resistor R12 is grounded; the non-inverting input terminal of the operational amplifier U2 is electrically connected to the normally closed terminal 4 of the relay K2 through a resistor R13, the inverting input terminal of the operational amplifier U2 is grounded through a resistor R14, the output terminal of the operational amplifier U2 is electrically connected to the inverting input terminal of the operational amplifier U2 through a feedback resistor R17, and the output terminal of the operational amplifier U2 is electrically connected to the second input terminal of the controller.

[0020] By adopting the above technical solution, the current output from the normally closed terminal 4 of relay K2 is differentially amplified through operational amplifier U2 and peripheral components, ensuring accurate acquisition of forward current and ripple signal after shutdown.

[0021] Preferably, the second current detection module further includes a power supply V2, a resistor R15, and a resistor R16. The voltage output terminal of the power supply V2 is grounded in sequence through resistor R15 and resistor R16, and the connection point between resistor R15 and resistor R16 is electrically connected to the non-inverting input terminal of operational amplifier U2.

[0022] By adopting the above technical solution, a DC bias is provided to the non-inverting input of the operational amplifier U2, avoiding distortion of the negative ripple signal when powered by a single power supply and ensuring full waveform acquisition.

[0023] Preferably, the first motor drive module further includes diodes D1 and D2. The voltage output terminal of the external power supply is electrically connected to the anode of diode D1, and the cathode of diode D1 is electrically connected to pin 2 of relay K1. The anode of diode D2 is electrically connected to pin 2 of relay K1, and the cathode of diode D2 is electrically connected to pin 1 of relay K1.

[0024] By adopting the above technical solution, diode D1 provides reverse power connection protection, and diode D2 provides a freewheeling circuit for relay K1, suppressing the reverse electromotive force when the coil is de-energized.

[0025] Preferably, the second motor drive module further includes diodes D3 and D4. The voltage output terminal of the external power supply is electrically connected to the anode of diode D3, and the cathode of diode D3 is electrically connected to pin 2 of relay K2. The anode of diode D4 is electrically connected to pin 2 of relay K2, and the cathode of diode D4 is electrically connected to pin 1 of relay K2.

[0026] By adopting the above technical solution, diode D3 provides reverse power connection protection, and diode D4 provides a freewheeling circuit for relay K2, suppressing the reverse electromotive force when the coil is de-energized.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] 1. Through the dual relay architecture and dual current detection module, it can not only monitor the operating current when the motor is working normally, but also continuously capture the ripple signal generated by rotor inertia after the motor stops, realizing full-cycle status monitoring from operation to complete stop, and providing more comprehensive operating data for the motor system;

[0029] 2. Differential amplification is performed on the sampling signal output by the first motor drive module and the sampling signal output by the second motor drive module, so that the controller can receive current within a suitable range and realize the detection of current signal. Attached Figure Description

[0030] Figure 1 This is a schematic block diagram of an embodiment of this application;

[0031] Figure 2 This is a circuit diagram of the first motor drive module and the second motor drive module in the embodiments of this application;

[0032] Figure 3 This is a circuit diagram of the first motor control module and the second motor control module in the embodiments of this application;

[0033] Figure 4 This is a circuit diagram of the first current detection module in an embodiment of this application;

[0034] Figure 5 This is a circuit diagram of the second current detection module in an embodiment of this application.

[0035] Reference numerals: 1. First motor drive module; 2. Second motor drive module; 3. First motor control module; 4. Second motor control module; 5. First current detection module; 6. Second current detection module. Detailed Implementation

[0036] The following combination Figures 1-5 This application will be described in further detail.

[0037] This application discloses a ripple signal acquisition circuit after a motor stops.

[0038] Reference Figure 1 A ripple signal acquisition circuit for a motor after it stops includes an external power supply BAT, a controller, a first motor drive module 1, a second motor drive module 2, a first motor control module 3, a second motor control module 4, a first current detection module 5, and a second current detection module 6. The voltage output terminal of the external power supply BAT is electrically connected to the power supply terminals of the first motor drive module 1 and the second motor drive module 2, respectively, and the output terminals of the first motor drive module 1 and the second motor drive module 2 are electrically connected to pins 1 and 2 of the motor, respectively. The first motor drive module 1 is controlled and connected to the first motor control module 3, and the second motor drive module 2 is controlled and connected to the second motor control module 4, thereby controlling the on / off state and magnitude of the motor current, and thus controlling the motor's rotation direction and speed. The sampling terminal of the first motor drive module 1 is electrically connected to the input terminal of the first current detection module 5, and the sampling terminal of the second motor drive module 2 is electrically connected to the input terminal of the second current detection module 6. The output terminals of the first current detection module 5 and the second current detection module 6 are electrically connected to the input terminal of the controller, thereby detecting the forward and reverse current of the motor and detecting ripple current after the motor stops.

[0039] Reference Figure 2 The first motor drive module 1 includes a relay K1, a diode D1, and a diode D2. The voltage output terminal of the external power supply BAT is electrically connected to the anode of diode D1, and the cathode of diode D1 is electrically connected to pin 2 of relay K1. The anode of diode D2 is electrically connected to pin 2 of relay K1, and the cathode of diode D2 is electrically connected to pin 1 of relay K1. Pin 1 of relay K1 is controlled to be connected to the first motor control module 3. Pin 1 of the motor is electrically connected to the common terminal 3 of relay K1, the normally open terminal 5 of relay K1 is electrically connected to the voltage output terminal of the external power supply BAT, and the normally closed terminal 4 of relay K1 is set as the sampling terminal of the first motor drive module 1.

[0040] When relay K1 is de-energized, normally closed pin 4 and common pin 3 are electrically connected, and motor pin 1 is grounded through the first current detection module 5. When relay K1 is de-energized, normally open pin 5 and common pin 3 are electrically connected, and motor pin 1 is energized. Diode D1 acts as a reverse connection protector, ensuring that current flows only in the forward direction from the external power supply BAT into relay K1. Diode D2 acts as a freewheeling diode; when relay K1 is de-energized, a reverse electromotive force is generated, and diode D2 provides a discharge path to protect the circuit.

[0041] The second motor drive module 2 and the first motor drive module 1 have basically the same structure, including relay K2, diode D3 and diode D4. Pin 1 of relay K2 is connected to the second motor control module 4, pin 2 of the motor is electrically connected to the common terminal pin 3 of relay K2, the normally open terminal pin 5 of relay K2 is electrically connected to the voltage output terminal of the external power supply BAT, and the normally closed terminal pin 4 of relay K2 is set as the sampling terminal of the second motor drive module 2.

[0042] When relay K1 is energized and relay K2 is de-energized, pin 1 of the motor is energized and pin 2 is grounded. At this time, the motor rotates forward and the first current monitoring module starts working. When relay K2 is energized and relay K1 is de-energized, pin 2 of the motor is energized and pin 1 is grounded. At this time, the motor rotates in reverse and the second current monitoring module starts working.

[0043] Reference Figure 3 The first motor control module 3 includes a transistor Q1, a voltage divider resistor R1, and a voltage divider resistor R2. The first output terminal of the controller, Relay LS0, is grounded through the voltage divider resistors R1 and R2 in sequence. The connection point between the voltage divider resistors R1 and R2 is electrically connected to the base of the transistor Q1. The emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is electrically connected to pin 1 of the relay K1.

[0044] When the controller's first output terminal Relay LS0 outputs a high level, transistor Q1 is turned on, and pin 1 of relay K1 is grounded, enabling relay K1 to operate. When the controller's first output terminal Relay LS0 outputs a low level, transistor Q1 is turned off, and pin 1 of relay K1 is left floating. Voltage divider resistors R1 and R2 are used to provide a suitable base bias voltage, allowing transistor Q1 to operate in the appropriate amplification region.

[0045] The second motor control module 4 has a basically the same structure as the first motor control module 3, including transistor Q2, voltage divider resistors R3 and R4. The first output terminal Relay LS1 of the controller is grounded through voltage divider resistors R3 and R4 in sequence. The connection point between voltage divider resistors R3 and R4 is electrically connected to the base of transistor Q2. The emitter of transistor Q2 is grounded, and the collector of transistor Q2 is electrically connected to pin 1 of relay K2.

[0046] Reference Figure 3 The first current detection module 5 includes a power supply V1, an operational amplifier U1, and a feedback resistor R10. The voltage output terminal of the power supply V1 is electrically connected to the power supply terminal of the operational amplifier U1, and the ground terminal of the operational amplifier U1 is grounded. The sampling terminal of the first motor drive module 1 is grounded through a sampling resistor R5. The non-inverting input terminal of the operational amplifier U1 is electrically connected to the sampling terminal of the first motor drive module 1 through a resistor R6, and the inverting input terminal of the operational amplifier U1 is grounded through a resistor R7. The non-inverting input terminal of the operational amplifier U1 is electrically connected to the inverting input terminal of the operational amplifier U1 through a capacitor C1, which acts as a filter. The output terminal of the operational amplifier U1 is electrically connected to the inverting input terminal of the operational amplifier U1 through a feedback resistor R10, and a capacitor C2 is connected in parallel across the two ends of the feedback resistor R1. The output terminal of the operational amplifier U1 is electrically connected to the first input terminal of the controller through a resistor R11, and the first input terminal of the controller is used to receive the inverted current signal CCW Current Sample. Furthermore, the first input terminal of the controller is grounded through capacitor C3, which improves the stability of the inverted current signal CCW Current Sample.

[0047] Furthermore, the voltage output terminal of power supply V1 is grounded in sequence through resistors R8 and R9, and the connection point between resistors R8 and R9 is electrically connected to the non-inverting input terminal of operational amplifier U1 to establish signal bias, so that the output voltage of operational amplifier U1 is always within the detectable range.

[0048] Operational amplifier U1 is used to differentially amplify the sampling signal output from the sampling terminal of the first motor drive module 1, so that the controller can receive current within a suitable range and realize the detection of current signal. Capacitor C3 is used to minimize operational amplifier oscillation.

[0049] The second current detection module 6 has a basically the same structure as the first current detection module 5, including a power supply V2, an operational amplifier U2, a feedback resistor R17, capacitors C4, C5, and C6. The sampling terminal of the second motor drive module 2 is grounded through the sampling resistor R12. The non-inverting input terminal of the operational amplifier U2 is electrically connected to the sampling terminal of the second motor drive module 2 through resistor R13, and the inverting input terminal of the operational amplifier U2 is grounded through resistor R14. The output terminal of the operational amplifier U2 is electrically connected to the second input terminal of the controller through resistor R18, and the second input terminal of the controller is used to receive the forward rotation current signal CW CurrentSample. The voltage output terminal of the power supply V2 is grounded sequentially through resistors R15 and R16, and is electrically connected to the non-inverting input terminal of the operational amplifier U2 through the connection point between resistors R15 and R16.

[0050] When the motor stops, the normally closed contacts of relays K1 and K2 close. The motor rotor continues to rotate due to inertia, generating a back electromotive force (EMF). A decaying AC ripple voltage is output from the motor terminals. The EMF output from pin 1 is converted into a voltage signal and input to the controller via the normally closed contact of relay K1 and the first current detection module 5. Similarly, the EMF output from pin 2 is input to the controller via the normally closed contact of relay K2 and the second current detection module 6. This allows the controller to detect whether the motor has completely stopped.

[0051] The implementation principle of the ripple signal acquisition circuit for motor stop according to an embodiment of this application is as follows: An external power supply powers the first motor drive module 1 and the second motor drive module 2. The first motor control module 3 and the second motor control module 4 control the operating states of the first motor drive module 1 and the second motor drive module 2 respectively, thereby controlling the direction of motor rotation. The first current detection module 5 and the second current detection module 6 detect the forward and reverse currents of the motor respectively and transmit the detected signals to the controller. When the motor stops, the motor rotor continues to rotate due to inertia and generates a reverse electromotive force. A decaying AC ripple voltage is output across the motor terminals. This ripple voltage is input to the controller through the first current detection module 5 and the second current detection module 6, enabling the controller to detect whether the motor has completely stopped. Compared with existing technologies, this circuit design can more accurately detect the motor's operating state, avoiding the problem of affecting the normal operation and precise control of subsequent equipment due to the inability to accurately determine whether the motor has completely stopped, thus improving the accuracy and reliability of motor control and detection.

[0052] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A ripple signal acquisition circuit after a motor stops, characterized in that: include: The controller includes a first motor control module (3), a second motor control module (4), a first current detection module (5), and a second current detection module (6). The first motor control module (3) and the second motor control module (4) are both connected to the controller. The output terminals of the first current detection module (5) and the second current detection module (6) are electrically connected to the input terminals of the controller. The first motor drive module (1) includes a relay K1. The voltage output terminal of the external power supply is electrically connected to pin 2 of the relay K1, and pin 1 of the relay K1 is controlled to be connected to the first motor control module (3). Pin 1 of the motor is electrically connected to the common terminal pin 3 of the relay K1. The normally open terminal pin 5 of the relay K1 is electrically connected to the voltage output terminal of the external power supply, and the normally closed terminal pin 4 of the relay K1 is electrically connected to the input terminal of the first current detection module (5). The second motor drive module (2) includes a relay K2. The voltage output terminal of the external power supply is electrically connected to pin 2 of the relay K2, and pin 1 of the relay K2 is controlled to be connected to the second motor control module (4). Pin 2 of the motor is electrically connected to the common terminal pin 3 of the relay K2. The normally open terminal pin 5 of the relay K2 is electrically connected to the voltage output terminal of the external power supply, and the normally closed terminal pin 4 of the relay K2 is electrically connected to the input terminal of the second current detection module (6).

2. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The first motor control module (3) includes a transistor Q1, a voltage divider resistor R1 and a voltage divider resistor R2. The first control output terminal of the controller is electrically connected to the base of the transistor Q1 through the voltage divider resistor R1 and the voltage divider resistor R2. The emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is electrically connected to pin 1 of the relay K1.

3. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The second motor control module (4) includes a transistor Q2, a voltage divider resistor R3 and a voltage divider resistor R4. The second control output terminal of the controller is electrically connected to the base of the transistor Q2 through the voltage divider resistor R3 and the voltage divider resistor R4. The emitter of the transistor Q2 is grounded, and the collector of the transistor Q2 is electrically connected to pin 1 of the relay K2.

4. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The first current detection module (5) includes an operational amplifier U1, a sampling resistor R5, and a feedback resistor R10; one end of the sampling resistor R5 is electrically connected to the normally closed terminal 4 of the relay K1, and the other end of the sampling resistor R5 is grounded; the non-inverting input terminal of the operational amplifier U1 is electrically connected to the normally closed terminal 4 of the relay K1 through a resistor R6, the inverting input terminal of the operational amplifier U1 is grounded through a resistor R7, the output terminal of the operational amplifier U1 is electrically connected to the inverting input terminal of the operational amplifier U1 through a feedback resistor R10, and the output terminal of the operational amplifier U1 is electrically connected to the first input terminal of the controller.

5. The ripple signal acquisition circuit after a motor stops, as described in claim 4, is characterized in that: The first current detection module (5) also includes a power supply V1, a resistor R8 and a resistor R9. The voltage output terminal of the power supply V1 is grounded in sequence through the resistor R8 and the resistor R9, and the connection point between the resistor R8 and the resistor R9 is electrically connected to the non-inverting input terminal of the operational amplifier U1.

6. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The second current detection module (6) includes an operational amplifier U2, a sampling resistor R12, and a feedback resistor R17; one end of the sampling resistor R12 is electrically connected to the normally closed terminal 4 of the relay K2, and the other end of the sampling resistor R12 is grounded; the non-inverting input terminal of the operational amplifier U2 is electrically connected to the normally closed terminal 4 of the relay K2 through a resistor R13, the inverting input terminal of the operational amplifier U2 is grounded through a resistor R14, the output terminal of the operational amplifier U2 is electrically connected to the inverting input terminal of the operational amplifier U2 through a feedback resistor R17, and the output terminal of the operational amplifier U2 is electrically connected to the second input terminal of the controller.

7. The ripple signal acquisition circuit after a motor stops, as described in claim 6, is characterized in that: The second current detection module (6) also includes a power supply V2, a resistor R15 and a resistor R16. The voltage output terminal of the power supply V2 is grounded in sequence through the resistor R15 and the resistor R16, and the connection point between the resistor R15 and the resistor R16 is electrically connected to the non-inverting input terminal of the operational amplifier U2.

8. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The first motor drive module (1) further includes diodes D1 and D2. The voltage output terminal of the external power supply is electrically connected to the anode of diode D1, and the cathode of diode D1 is electrically connected to pin 2 of relay K1. The anode of diode D2 is electrically connected to pin 2 of relay K1, and the cathode of diode D2 is electrically connected to pin 1 of relay K1.

9. The ripple signal acquisition circuit after a motor stops, as described in claim 1, is characterized in that: The second motor drive module (2) also includes diodes D3 and D4. The voltage output terminal of the external power supply is electrically connected to the anode of diode D3, and the cathode of diode D3 is electrically connected to pin 2 of relay K2. The anode of diode D4 is electrically connected to pin 2 of relay K2, and the cathode of diode D4 is electrically connected to pin 1 of relay K2.

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