A symmetrical differential amplification current ripple collection circuit device

Abstract

The present invention discloses a symmetrical differential amplification current ripple collection circuit device, comprising an inductance collection circuit (W), a filtering circuit (X), a symmetrical differential amplification circuit (Y) and a comparison shaping circuit (Z). The present invention directly collects the inductance signal of the high-frequency transformer corresponding to the rotation of the motor for filtering, symmetrical differential amplification and comparison shaping, obtains a pulse square wave signal for data processing by a microprocessor, and obtains the number of motor rotations and the rotation direction data. The technical solution overcomes the problems and shortcomings of the prior art, such as high cost, large size and high failure rate, so that the current ripple collection circuit achieves the purpose of reducing cost, reducing size and reducing failures.

Description

Technical Field

[0001] The invention relates to a circuit device, in particular to a symmetrical differential amplification current ripple collection circuit device for collecting the number of rotations of a motor. Background Art

[0002] Note: The motor described in this article is a brushed DC motor; the current ripple acquisition circuit is a circuit device used to collect the number of motor rotations; by calculating and processing the number of motor rotations, the exact position data information of the object driven by the motor can be obtained, such as the displacement data of the car seat, window glass, tailgate, etc.;

[0003] The current ripple collection circuit of the prior art, referring to the patent literature, is a circuit device CN201520613960.5 for collecting the number of rotations of a motor. The patented device is provided with a stall sampling resistor, and the switching circuit QH is provided with an A relay and a B relay for identifying the rotation direction. In actual production and application, the cost is high, the size is large, the mechanical durability of the relay is poor, and the failure rate is high; therefore, the prior art has the problems and shortcomings of high cost, large size, and high failure rate. Summary of the invention

[0004] In view of the problems and shortcomings of the above-mentioned prior art, the present invention adopts a device composed of an inductance collection circuit, a filter circuit, a symmetrical differential amplifier circuit, and a comparison shaping circuit, wherein the inductance collection circuit is composed of a high-frequency transformer and a motor, the primary coil of the high-frequency transformer is connected in series with the motor, the upper end of the primary coil of the high-frequency transformer is connected to a 12V power supply, and the lower end of the motor is grounded;

[0005] The filter circuit is composed of a resistor R1, a resistor R2, a capacitor C1 and a capacitor C2. The left end of the resistor R1 is connected to the upper end of the secondary coil of the high-frequency transformer, the right end of the resistor R1 is connected in series with the upper end of the capacitor C1, and the lower end of the capacitor C1 is grounded; the left end of the resistor R2 is connected to the lower end of the secondary coil of the high-frequency transformer, the right end of the resistor R2 is connected in series with the upper end of the capacitor C2, and the lower end of the capacitor C2 is grounded;

[0006] The symmetrical differential amplifier circuit is composed of a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C3, a capacitor C4, an operational amplifier U1-A, an operational amplifier U1-B, and an operational amplifier U1-D. The positive input electrode of the operational amplifier U1-A, the upper end of the resistor R4, the left end of the resistor R6, and the negative input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R4 is grounded; the negative input electrode of the operational amplifier U1-A, the left end of the resistor R5, the upper end of the resistor R3, and the positive input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R3 is grounded; The right end of resistor R5, the left end of capacitor C3, and the output end of operational amplifier U1-A are connected in parallel, the right end of capacitor C3 and the left end of resistor R7 are connected in series, the right end of resistor R7, the left end of resistor R9, the negative input electrode of operational amplifier U1-D and the upper end of resistor R10 are connected in parallel, the right end of resistor R9 is connected to the output end of operational amplifier U1-D, and the lower end of resistor R10 is grounded; the right end of resistor R6, the left end of capacitor C4 and the output end of operational amplifier U1-B are connected in parallel, the right end of capacitor C4 and the left end of resistor R8 are connected in series, and the right end of resistor R8 is connected to the positive input electrode of operational amplifier U1-D;

[0007] The comparison shaping circuit is composed of a resistor R11, a resistor R12, a resistor R13, and an operational amplifier U1-C. The right end of the resistor R13 is connected to the positive input electrode of the operational amplifier U1-C, the upper end of the resistor R12 is connected to the power supply 5V, the lower end of the resistor R12, the negative input electrode of the operational amplifier U1-C and the upper end of the resistor R11 are connected in parallel, and the lower end of the resistor R11 is grounded.

[0008] The right end of the resistor R1 of the filter circuit is connected to the positive input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit, the right end of the resistor R2 of the filter circuit is connected to the negative input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit, the output end of the operational amplifier U1-D of the symmetrical differential amplifier circuit is connected to the left end of the resistor R13 of the comparison shaping circuit; the output OUT of the operational amplifier U1-C is connected to the microprocessor;

[0009] When working, in the inductance collection circuit, the current of the driving motor passes through the primary coil of the high-frequency transformer. The current ripple generated when the motor rotates is coupled from the primary coil of the high-frequency transformer to the secondary coil. The upper and lower ends of the secondary coil of the high-frequency transformer will produce two complex waveforms that are approximately sinusoidal with a phase difference of 180°. After that, the two complex waveforms are filtered by the resistor R1, resistor R2, capacitor C1 and capacitor C2 of the filter circuit to obtain two sinusoidal wave signals with a phase difference of 180°. After that, the two sinusoidal wave signals are respectively passed through the operational amplifier U1 of the symmetrical differential amplifier circuit. -A, symmetrical differential amplification and power amplification of operational amplifier U1-B and operational amplifier U1-D, and then square wave conversion is performed through the operational amplifier U1-C of the comparison shaping circuit to obtain two groups of pulse square wave signals with a phase difference of 180°. The two groups of pulse square wave signals are transmitted to the microprocessor through the output OUT of the operational amplifier U1-C for data processing to obtain the technical solution of the number of motor rotations and the rotation direction data, and provide a symmetrical differential amplification current ripple acquisition circuit device, aiming to enable the current ripple acquisition circuit to achieve the purpose of reducing cost, reducing size and reducing failures.

[0010] The object of the present invention is achieved as follows: a symmetrical differential amplification current ripple collection circuit device, including an inductance collection circuit, a filter circuit, a symmetrical differential amplification circuit and a comparison shaping circuit, wherein: the inductance collection circuit is composed of a high-frequency transformer and a motor, the primary coil of the high-frequency transformer is connected in series with the motor, the upper end of the primary coil of the high-frequency transformer is connected to a 12V power supply, and the lower end of the motor is grounded;

[0011] The filtering circuit is composed of a resistor R1, a resistor R2, a capacitor C1 and a capacitor C2. The left end of the resistor R1 is connected to the upper end of the secondary coil of the high-frequency transformer, the right end of the resistor R1 is connected in series with the upper end of the capacitor C1, and the lower end of the capacitor C1 is grounded; the left end of the resistor R2 is connected to the lower end of the secondary coil of the high-frequency transformer, the right end of the resistor R2 is connected in series with the upper end of the capacitor C2, and the lower end of the capacitor C2 is grounded;

[0012] The symmetrical differential amplifier circuit is composed of resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, resistor R10, capacitor C3, capacitor C4, operational amplifier U1-A, operational amplifier U1-B and operational amplifier U1-D. The positive input electrode of the operational amplifier U1-A, the upper end of the resistor R4, the left end of the resistor R6 and the negative input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R4 is grounded; the negative input electrode of the operational amplifier U1-A, the left end of the resistor R5, the upper end of the resistor R3 and the positive input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R3 is connected ground; the right end of resistor R5, the left end of capacitor C3, and the output end of operational amplifier U1-A are connected in parallel, the right end of capacitor C3 and the left end of resistor R7 are connected in series, the right end of resistor R7, the left end of resistor R9, the negative input electrode of operational amplifier U1-D and the upper end of resistor R10 are connected in parallel, the right end of resistor R9 is connected to the output end of operational amplifier U1-D, and the lower end of resistor R10 is grounded; the right end of resistor R6, the left end of capacitor C4 and the output end of operational amplifier U1-B are connected in parallel, the right end of capacitor C4 and the left end of resistor R8 are connected in series, and the right end of resistor R8 is connected to the positive input electrode of operational amplifier U1-D;

[0013] The comparison shaping circuit is composed of a resistor R11, a resistor R12, a resistor R13 and an operational amplifier U1-C, the right end of the resistor R13 is connected to the positive input of the operational amplifier U1-C, the upper end of the resistor R12 is connected to the power supply 5V, the lower end of the resistor R12, the negative input of the operational amplifier U1-C and the upper end of the resistor R11 are connected in parallel, and the lower end of the resistor R11 is grounded;

[0014] The right end of the resistor R1 of the filter circuit is connected to the positive input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit, the right end of the resistor R2 of the filter circuit is connected to the negative input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit, the output end of the operational amplifier U1-D of the symmetrical differential amplifier circuit is connected to the left end of the resistor R13 of the comparison shaping circuit; the output OUT of the operational amplifier U1-C is connected to the microprocessor.

[0015] The directions described in the above circuit structure are based on the up, down, left and right directions of the circuit diagram of the device.

[0016] Working principle and beneficial effects

[0017] During operation, in the inductance acquisition circuit, the current driving the motor passes through the primary coil of the high-frequency transformer. The current ripple generated when the motor rotates is coupled from the primary coil of the high-frequency transformer to the secondary coil. The upper and lower ends of the secondary coil of the high-frequency transformer will produce two complex waveforms that are approximately sinusoidal with a phase difference of 180°. Afterwards, the two complex waveforms are filtered by the resistor R1, resistor R2, capacitor C1 and capacitor C2 of the filter circuit to obtain two sinusoidal wave signals with a phase difference of 180°. Afterwards, the two sinusoidal wave signals are respectively symmetrically differentially amplified and power amplified by the operational amplifier U1-A, operational amplifier U1-B and operational amplifier U1-D of the symmetrical differential amplifier circuit, and then square wave converted by the operational amplifier U1-C of the comparison shaping circuit to obtain two groups of pulse square wave signals with a phase difference of 180°. The two groups of pulse square wave signals are transmitted to the microprocessor through the output OUT of the operational amplifier U1-C for data processing to obtain data on the number of motor rotations and the direction of rotation.

[0018] The device has a simple structure and reliable operation. It directly collects the inductance signal of the high-frequency transformer corresponding to the rotation of the motor for filtering, symmetrical differential amplification, and comparison shaping to obtain a pulse square wave signal for data processing by the microprocessor. Since the trouble-free operating life of the electronic circuit is longer than that of a mechanical relay and the size is also smaller than that of the relay, the device avoids the drawbacks of the prior art of using a stalled sampling resistor and a switching loop QH relay, thereby reducing the cost, size, and failure of the current ripple collection circuit of the number of motor rotations.

[0019] As mentioned above, the present invention adopts a device composed of an inductance collection circuit, a filtering circuit, a symmetrical differential amplifier circuit, and a comparison shaping circuit, wherein the inductance collection circuit is composed of a high-frequency transformer and a motor, the filtering circuit is composed of a resistor R1, a resistor R2, a capacitor C1, and a capacitor C2, the symmetrical differential amplifier circuit is composed of a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C3, a capacitor C4, an operational amplifier U1-A, an operational amplifier U1-B, and an operational amplifier U1-D, the comparison shaping circuit is composed of a resistor R11, a resistor R12, a resistor R13, and an operational amplifier U1-C, and the right end of the resistor R1 of the filtering circuit is connected to the positive input terminal of the operational amplifier U1-A of the symmetrical differential amplifier circuit. The right end of the resistor R2 of the filter circuit is connected to the negative input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit, and the output end of the operational amplifier U1-D of the symmetrical differential amplifier circuit is connected to the left end of the resistor R13 of the comparison and shaping circuit; the output OUT of the operational amplifier U1-C is connected to the microprocessor; when working, the inductance signal of the high-frequency transformer corresponding to the rotation of the motor is directly collected for filtering, symmetrical differential amplification, and comparison shaping to obtain a pulse square wave signal for data processing by the microprocessor, which overcomes the problems and shortcomings of the prior art such as high cost, large size, and high failure rate. A symmetrical differential amplification current ripple collection circuit device is provided, so that the current ripple collection circuit achieves the purpose of reducing cost, reducing size, and reducing failures. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a principle block diagram of a symmetrical differential amplification current ripple collection circuit device of the present invention;

[0021] Figure 2 The present invention is a schematic diagram of the circuit principle of a symmetrical differential amplification current ripple collection circuit device.

[0022] The present invention will be further described in detail below in conjunction with the embodiments in the accompanying drawings, but this should not be construed as any limitation to the present invention.

[0023] In the figure: inductance acquisition circuit W, high-frequency transformer L, motor M, filter circuit X, resistor R1, resistor R2, capacitor C1 and capacitor C2, symmetrical differential amplifier circuit Y, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, resistor R10, capacitor C3, capacitor C4, operational amplifier U1-A, operational amplifier U1-B, operational amplifier U1-D, comparison shaping circuit Z, resistor R11, resistor R12, resistor R13, operational amplifier U1-C, output OUT. DETAILED DESCRIPTION

[0024] See also Figure 1 , Figure 2 A symmetrical differential amplification current ripple collection circuit device of the present invention comprises an inductance collection circuit W, a filter circuit X, a symmetrical differential amplification circuit Y and a comparison shaping circuit Z, wherein: the inductance collection circuit W is composed of a high-frequency transformer L and a motor M, the primary coil of the high-frequency transformer L is connected in series with the motor M, the upper end of the primary coil of the high-frequency transformer L is connected to a 12V power supply, and the lower end of the motor M is grounded;

[0025] The filter circuit X is composed of a resistor R1, a resistor R2, a capacitor C1 and a capacitor C2. The left end of the resistor R1 is connected to the upper end of the secondary coil of the high-frequency transformer L, the right end of the resistor R1 is connected in series with the upper end of the capacitor C1, and the lower end of the capacitor C1 is grounded; the left end of the resistor R2 is connected to the lower end of the secondary coil of the high-frequency transformer L, the right end of the resistor R2 is connected in series with the upper end of the capacitor C2, and the lower end of the capacitor C2 is grounded;

[0026] The symmetrical differential amplifier circuit Y is composed of a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a capacitor C3, a capacitor C4, an operational amplifier U1-A, an operational amplifier U1-B and an operational amplifier U1-D. The positive input electrode of the operational amplifier U1-A, the upper end of the resistor R4, the left end of the resistor R6 and the negative input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R4 is grounded; the negative input electrode of the operational amplifier U1-A, the left end of the resistor R5, the upper end of the resistor R3 and the positive input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R3 is connected ground; the right end of resistor R5, the left end of capacitor C3, and the output end of operational amplifier U1-A are connected in parallel, the right end of capacitor C3 and the left end of resistor R7 are connected in series, the right end of resistor R7, the left end of resistor R9, the negative input electrode of operational amplifier U1-D and the upper end of resistor R10 are connected in parallel, the right end of resistor R9 is connected to the output end of operational amplifier U1-D, and the lower end of resistor R10 is grounded; the right end of resistor R6, the left end of capacitor C4 and the output end of operational amplifier U1-B are connected in parallel, the right end of capacitor C4 and the left end of resistor R8 are connected in series, and the right end of resistor R8 is connected to the positive input electrode of operational amplifier U1-D;

[0027] The comparison shaping circuit Z is composed of a resistor R11, a resistor R12, a resistor R13 and an operational amplifier U1-C, the right end of the resistor R13 is connected to the positive input of the operational amplifier U1-C, the upper end of the resistor R12 is connected to the power supply 5V, the lower end of the resistor R12, the negative input of the operational amplifier U1-C and the upper end of the resistor R11 are connected in parallel, and the lower end of the resistor R11 is grounded;

[0028] The right end of the resistor R1 of the filter circuit X is connected to the positive input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit Y, the right end of the resistor R2 of the filter circuit X is connected to the negative input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit Y, the output end of the operational amplifier U1-D of the symmetrical differential amplifier circuit Y is connected to the left end of the resistor R13 of the comparison shaping circuit Z; the output OUT of the operational amplifier U1-C is connected to the microprocessor.

[0029] The directions described in the above circuit structure are based on the up, down, left and right directions of the circuit diagram of the device.

[0030] Working principle and beneficial effects

[0031] During operation, in the inductance acquisition circuit W, the current of the driving motor M passes through the primary coil of the high-frequency transformer L. The current ripple generated when the motor M rotates is coupled from the primary coil of the high-frequency transformer L to the secondary coil. The upper and lower ends of the secondary coil of the high-frequency transformer L will generate two complex waveforms that are approximately sinusoidal with a phase difference of 180°. Afterwards, the two complex waveforms are filtered by the resistor R1, the resistor R2, the capacitor C1 and the capacitor C2 of the filter circuit X to obtain two sinusoidal wave signals with a phase difference of 180°. Afterwards, the two sinusoidal wave signals are respectively symmetrically differentially amplified and power amplified by the operational amplifier U1-A, the operational amplifier U1-B and the operational amplifier U1-D of the symmetrical differential amplifier circuit Y, and then square-wave converted by the operational amplifier U1-C of the comparison shaping circuit Z to obtain two groups of pulse square wave signals with a phase difference of 180°. The two groups of pulse square wave signals are transmitted to the microprocessor through the output OUT of the operational amplifier U1-C for data processing to obtain data on the number of revolutions and the direction of rotation of the motor M.

[0032] The device has a simple structure and reliable operation. It directly collects the inductance signal of the high-frequency transformer L corresponding to the rotation of the motor M, performs filtering, symmetrical differential amplification, and comparison shaping to obtain a pulse square wave signal for data processing by the microprocessor. Since the trouble-free operation life of the electronic circuit is longer than that of a mechanical relay and the size is also smaller than that of the relay, the device avoids the drawbacks of the prior art of using a locked-rotor sampling resistor and a switching loop QH relay, thereby reducing the cost, size, and failure of the current ripple collection circuit of the number of rotations of the motor M.

Claims

1. A symmetrical differential amplification current ripple collection circuit device, comprising an inductance collection circuit (W), a filter circuit (X), a symmetrical differential amplification circuit (Y) and a comparison shaping circuit (Z), characterized in that: The inductance collection circuit (W) is composed of a high-frequency transformer (L) and a motor (M), the primary coil of the high-frequency transformer (L) is connected in series with the motor (M), the upper end of the primary coil of the high-frequency transformer (L) is connected to a 12V power supply, and the lower end of the motor (M) is grounded; The filter circuit (X) is composed of a resistor R1, a resistor R2, a capacitor C1 and a capacitor C2, wherein the left end of the resistor R1 is connected to the upper end of the secondary coil of the high-frequency transformer (L), the right end of the resistor R1 is connected in series with the upper end of the capacitor C1, and the lower end of the capacitor C1 is grounded; the left end of the resistor R2 is connected to the lower end of the secondary coil of the high-frequency transformer (L), the right end of the resistor R2 is connected in series with the upper end of the capacitor C2, and the lower end of the capacitor C2 is grounded; The symmetrical differential amplifier circuit (Y) is composed of resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, resistor R10, capacitor C3, capacitor C4, operational amplifier U1-A, operational amplifier U1-B and operational amplifier U1-D. The positive input electrode of the operational amplifier U1-A, the upper end of the resistor R4, the left end of the resistor R6 and the negative input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R4 is grounded; the negative input electrode of the operational amplifier U1-A, the left end of the resistor R5, the upper end of the resistor R3 and the positive input electrode of the operational amplifier U1-B are connected in parallel, and the lower end of the resistor R3 is grounded. Grounded; the right end of resistor R5, the left end of capacitor C3, and the output end of operational amplifier U1-A are connected in parallel, the right end of capacitor C3 and the left end of resistor R7 are connected in series, the right end of resistor R7, the left end of resistor R9, the negative input electrode of operational amplifier U1-D and the upper end of resistor R10 are connected in parallel, the right end of resistor R9 is connected to the output end of operational amplifier U1-D, and the lower end of resistor R10 is grounded; the right end of resistor R6, the left end of capacitor C4 and the output end of operational amplifier U1-B are connected in parallel, the right end of capacitor C4 and the left end of resistor R8 are connected in series, and the right end of resistor R8 is connected to the positive input electrode of operational amplifier U1-D; The comparison shaping circuit (Z) is composed of a resistor R11, a resistor R12, a resistor R13 and an operational amplifier U1-C, the right end of the resistor R13 is connected to the positive input of the operational amplifier U1-C, the upper end of the resistor R12 is connected to the power supply 5V, the lower end of the resistor R12, the negative input of the operational amplifier U1-C and the upper end of the resistor R11 are connected in parallel, and the lower end of the resistor R11 is grounded; The right end of the resistor R1 of the filter circuit (X) is connected to the positive input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit (Y), the right end of the resistor R2 of the filter circuit (X) is connected to the negative input electrode of the operational amplifier U1-A of the symmetrical differential amplifier circuit (Y), the output end of the operational amplifier U1-D of the symmetrical differential amplifier circuit (Y) is connected to the left end of the resistor R13 of the comparison shaping circuit (Z); the output (OUT) of the operational amplifier U1-C is connected to the microprocessor.

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