CN201178394Y

CN201178394Y - DC motor controlling circuit

Info

Publication number: CN201178394Y
Application number: CNU2008200920672U
Authority: CN
Inventors: 白清利; 刘建伟; 董晓勇
Original assignee: Shenzhen H&T Intelligent Control Co Ltd
Current assignee: Shenzhen H&T Intelligent Control Co Ltd
Priority date: 2008-01-30
Filing date: 2008-01-30
Publication date: 2009-01-07
Anticipated expiration: 2018-01-30

Abstract

The utility model relates to a DC motor control circuit comprising an MCU (1) as well as a power supply (2), a reset circuit (3) and a crystal oscillating circuit (4) which are connected to the MCU (1), and the control circuit further comprises a zero crossing detection circuit (5), a motor steering circuit and a motor speed regulation circuit connected to the MCU (1). The DC motor control circuit has the advantages that the control of the DC motor in positive and negative directions can be reliably realized; through the adjustment of the angle of flow of a controlled silicon, the effective DC voltage value applied to the DC motor is changed, thereby regulating the rotation speed of the motor; and the realization is simple, the cost is low and the control process is easily realized.

Description

A kind of DC motor control circuit

Technical field

The utility model relates to DC motor control circuit, more particularly, relate to a kind of reliable direct current machine Rotation With Changing to and speed-regulating control circuit.

Background technology

In DC motor, with commutator and brush the direct current of input is become alternating current in the coil, commutator and brush are indispensable critical pieces in the direct current machine.The commutation control of direct current machine is the key link of DC MOTOR CONTROL.By changing motor steering, can realize the forward and backward of mechanical device, the moving of left and right relative position.Certainly will increase wear of brush and frequently turn to, therefore, how realize this controlling unit reliably, significant to prolonging electrical machinery life.In addition, how to change thyristor operating angle, carrying out electric machine speed regulation also is the key that realizes that this circuit is realized.

The utility model content

The technical problems to be solved in the utility model is, goes up at existing that direct current machine rotates and the above-mentioned defective of speed governing, provide a kind of reliable direct current machine Rotation With Changing to and speed-regulating control circuit.

The technical scheme that its technical problem that solves the utility model adopts is: construct a kind of DC motor control circuit, the power supply, reset circuit, the crystal oscillating circuit that comprise MCU and be connected to MCU, it is characterized in that, also comprise the zero cross detection circuit, motor steering circuit and the motor speed control circuit that are connected with MCU.

In DC motor control circuit described in the utility model, described motor steering circuit comprises two relay R Y1, control triode TR1, current-limiting resistance R8 and the Transient Suppression Diode D2 of putting of double-pole, the two relay R Y1 that put of double-pole connect with current-limiting resistance R8, control triode TR1, and D2 is in parallel with Transient Suppression Diode.

In DC motor control circuit described in the utility model, described motor speed control circuit comprises two-way optocoupler U1, the bidirectional triode thyristor SCR1 of series connection and is used to reduce the absorption circuit of two-way optocoupler U1 false triggering rate.

In DC motor control circuit described in the utility model, described zero cross detection circuit comprises optocoupler U3, divider resistance R10, R11, and described optocoupler U3 is connected to AC power by current-limiting resistance R10, R11.

Implement DC motor control circuit of the present utility model, have following beneficial effect:

Realize the forward and reverse control of direct current machine reliably; By regulating the silicon controlled angle of flow, change the effective dc voltage value that is applied on the direct current machine, thus the scalable motor speed; Realize that simply with low cost, control procedure easily realizes.

Description of drawings

The utility model is described in further detail below in conjunction with drawings and Examples, in the accompanying drawing:

Fig. 1 is the hardware system block diagram of the utility model DC motor control circuit;

Fig. 2 is the circuit theory diagrams of the utility model DC motor control circuit;

Fig. 3 is the control flow chart of the utility model DC motor control circuit.

Embodiment

The purpose of the utility model DC motor control circuit is to realize that reliably direct current machine turns to and speed regulating control.This DC motor control circuit realizes simple, and with low cost, control procedure realizes easily, can be widely used in coffee machine and ferment in mechanism, treadmill crane and the similar various kinetic control system.

As shown in Figure 1, there is shown the hardware system block diagram of the utility model DC motor control circuit, comprise MCU 1 and the power supply 2 that is connected with MCU 1, reset circuit 3, crystal oscillating circuit 4, zero cross detection circuit 5, motor steering circuit 6, motor speed control circuit 7.Zero cross detection circuit 5 produces the square wave zero cross signal, and MCU 1 controls motor steering circuit 6 and motor speed control circuit 7 by detecting zero cross signal.

Fig. 2 is the circuit theory diagrams of the utility model DC motor control circuit.There is shown the schematic diagram of zero cross detection circuit 5, motor steering circuit 6, motor speed control circuit 7 and rectification circuit part.

Zero cross detection circuit 5 comprises optocoupler U3, divider resistance R10, R11, and optocoupler U3 is connected to AC power by current-limiting resistance R10, R11.The 220V AC signal inserts from CN1-1, the CN1-2 of L, N, through optocoupler U3, is the square-wave signal of 10ms in the P1.3 input port formation cycle of MCU 1.Wherein, the P1.3 mouth of MCU1 is set to the input port or is chosen as the external interrupt mouth.

Motor steering circuit 6 comprises two relay R Y1, control triode TR1, current-limiting resistance R8 and the Transient Suppression Diode D2 of putting of double-pole, and the two relay R Y1 that put of double-pole connect with current-limiting resistance R8, control triode TR1, and D2 is in parallel with Transient Suppression Diode.Motor steering circuit 6 is exported high and low level by the P1.2 mouth of MCU 1, and the control double-pole is two puts relay R Y1, reaches the purpose with direct current machine polarity input conversion.The P1.2 mouth of MCU 1 drives the base stage of triode TR1, and R8 is a current-limiting resistance, and Transient Suppression Diode D2 in parallel (model is 1N4148) is used for suppressing the moment of cutting off the power supply, the high pressure inverse peak voltage that produces on the coil.When the triode conducting, relay coil gets electric, and load motor is connected in the contact adhesive.

Motor speed control circuit 7 comprises two-way optocoupler U1, bidirectional triode thyristor SCR1, absorption circuit 8.Absorption circuit 8 comprises capacitor C 1 and resistance R 2, R3, R4, R5.Because the controllable silicon main control loop is in the forceful electric power circuit, voltage is higher, and electric current is bigger, so should separate with weak electrical loop.Optocoupler U1 is used for control signal and thyristor gating circuit are isolated.The direct current output of rectifier bridge U2 is subjected to the control of the P1.1 mouth of MCU 1, utilizes the P1.1 mouth, by the optocoupler U1 control SCR AC angle of flow, reaches the purpose of chopping regulating speed.As shown in Figure 2, the P1.1 mouth drives optocoupler U1 conducting, and C1 and R2, R3, R4, R5 are the RC absorption circuit among the figure, can reduce the false triggering rate of two-way optocoupler U1.In addition, because motor is an inductive load, its load current and voltage is homophase not, so voltage change ratio just raises, causes the controllable silicon false triggering easily, adds the RC capacitance-resistance and absorb link (R6, R7, C2) to reduce the rate of change of voltage in circuit.Piezo-resistance ZNR1 can suppress instantaneous pressure to be disturbed.

Behind power supply electrifying, AC power produces the square wave zero cross signal through two-way optocoupler U3.MCU 1 passes through to detect zero cross signal, the conducting of control controllable silicon SCR 1, and alternating voltage is added in rectifier bridge U2 input, and the direct current output of rectifier bridge U2 is controlled by the two relay R Y1 that put of double-pole.When P1.2 mouth output high level, triode TR1 conducting, the relay double-pole places the positive and negative end that connects rectifier bridge U2 direct current, direct current machine input positive and negative electrode; Otherwise when P1.2 mouth output low level, triode TR1 ends, and the relay double-pole places negative, positive end, and direct current machine inserts oppositely.The speed of direct current machine is to be determined by the voltage effective value that adds thereon, therefore, by P1.1 mouth output high-low level, control controllable silicon SCR 1 angle of flow, thus the voltage effective value on the change direct current machine reaches the effect of controlling motor speed.

Fig. 3 is the control flow chart of the utility model DC motor control circuit.In step 302, detect whether need to change direction, if desired, forward step 304 to, if do not need, then jump to step 306.In step 304, selective relay leaves/closes.In step 306, detect whether zero cross signal is arranged, if having, forward step 308 to, if do not have, then return.In step 308, change angle of flow required time.In step 310, drive controllable silicon.In step 312, detect whether need speed governing, if desired, forward step 306 to, if do not need, then return.

The utility model DC motor control circuit can realize the forward and reverse control of direct current machine reliably.By regulating the silicon controlled angle of flow, change the effective dc voltage value that is applied on the direct current machine, thus the scalable motor speed.This circuit is realized simple, and with low cost, control procedure easily realizes.

Claims

1, a kind of DC motor control circuit, the power supply (2), reset circuit (3), the crystal oscillating circuit (4) that comprise MCU (1) and be connected to MCU (1), it is characterized in that, also comprise the zero cross detection circuit (5), motor steering circuit (6) and the motor speed control circuit (7) that are connected with MCU (1).

2, DC motor control circuit according to claim 1, it is characterized in that, described motor steering circuit (6) comprises two relay R Y1, control triode TR1, current-limiting resistance R8 and the Transient Suppression Diode D2 of putting of double-pole, the two relay R Y1 that put of double-pole connect with current-limiting resistance R8, control triode TR1, and D2 is in parallel with Transient Suppression Diode.

3, DC motor control circuit according to claim 1 is characterized in that, described motor speed control circuit (7) comprises two-way optocoupler U1, the bidirectional triode thyristor SCR1 of series connection and is used to reduce the absorption circuit (8) of two-way optocoupler U1 false triggering rate.

4, DC motor control circuit according to claim 1 is characterized in that, described zero cross detection circuit (5) comprises optocoupler U3, divider resistance R10, R11, and described optocoupler U3 is connected to AC power by current-limiting resistance R10, R11.