SU1001407A1 - Dc control device - Google Patents

Description

(54) DEVICE FOR ELECTRIC MOTOR CONTROL

DIRECT CURRENT

one

The invention relates to electrical engineering and can be used to control current of stimuli loads.

A device for controlling the current of the traction motors is known, which provides a constant switching frequency of the pulse chopper by means of periodic pulses for switching off and containing a generator of driving pulses. Sov, connected through the corresponding differentiating circuits to the formers of the delayed and blocking pulses, as well as to the first input of the trigger connected to the output of the comparison block, 5 days. The output of the delayed pulse shaper is connected to the second trigger input and the pulse breaker booster of the half-turn interrupter, and the trigger output is connected with the booster amplifier to open the breaker. A blocking pulse former and an engine current sensor, 1 J are connected to the inputs of the comparison unit.

The disadvantage of this device is the significant ripple of the current of the core due to an abrupt change in voltage across the motor from a zero to its minimum value. In addition, with a small relative duration of inclusion, a violation of uniformity is possible. rotation, which limits the range of adjustment.

Claims (2)

Closest to the present invention, there is a device for controlling a direct current electric motor, which holds a power supply and a driver pulse generator connected via fo1. The worlds of blocking and delayed pulses to the inputs of the block switch-. cents, the other DXPIbi of which are connected to the outputs of the structure changing unit, the comparison unit and the inversion unit, connected to the pulse current converter core, the outputs of the switching unit are connected. through the trigger to the block of structure change, to the central input the coder is connected to a delay of 10 pulses, the output of the co-trigger with an amplifier connected to the control circuit of the pulse interrupter. The disadvantages of the known device are the significant pulsations of the regulated current, and, therefore, the motor torque at speeds that lead to a violation of the uniformity of rotation and an increase in losses in the engine, as well as to a decrease in the adjustment range. The purpose of the invention is to increase control quality and speed control range extension. The goal is achieved by the fact that the Device is additionally introduced. (and - 1) pulsed interrupters and dividing diodes, with the outputs of pulsed interrupters through {separate separator bottom and connected to the output of the electric motor, the output of which is connected to the power supply, and the series-connected register, one-vibration, comparator, integrator, integrator, integrator, integrator, integrator, one-way, one-way, comparator, one-way, one-way, comparator, one-way, one-way connectors. with the output of the inversion unit, the shift register under the amplifier to the amplifier, the outputs of which are connected to the control inputs of the impulse switches, the output of the one-oscillator is connected to the other inputs of the integrator and the unit for changing the structure; FIG. 1 is a diagram of the device; Fig. 2 are diagrams explaining the operation of the device. The device for controlling the direct current motor contains a power supply unit 1, a generator of 2 driving pulses connected via shapers 3 and 4 of delayed and blocking pulses to the inputs of the switching unit 5, the other inputs of which are connected to the outputs of the structure changing unit 6, the comparison unit 7 and the unit 8, connected to the pulse current converter 9, the core, the outputs of the switching unit 5 are connected via the trigger 1O to the measurement unit 6 of the structure; to the whole input of which is connected the driver 3 delayed pulses c, the output of the trigger 10 is connected to an amplifier 11 connected to the control circuit of pulsed interrupters 12.1-12, N, and the outputs of pulsed interrupters 12.1 D2. You are connected through dividing diodes 13.1-13, N and connected to the output side of the motor winding 14, the second output of which is connected to power supply 1, as well as successively connected shift register 15, single vibrator 16, comparator 17, and integrator 18, whose input is connected to the output of inversion unit 8, shift register 15 connected to amplifier 11, whose outputs are connected to supervisors pulse choppers s 12.1 - 12, N, output monostable 16 is connected to the other inputs of the integrator 18 and varying the structure unit 6. Comparison unit 7 comprises a sawtooth voltage generator 19 connected in series and a comparator 20, the input of the former 19 is connected to the pulse current converter 9, the core, and the output of the comparator 2O to one of the inputs of the switching unit 5 and 1 second input of the inversion unit 8 of the inversion unit 8. Inversion unit -8 comprises sequentially connected triggers 21 and a matching circuit 22, the first inputs of which are connected to the converter 9 of the current core, and the output of the circuit 22 to one of the inputs of the switching unit 5. Anchor motor circuit. 14 is shunted by a reverse diode 23; the device operates as follows; Current control of the core 14 is carried out with a constant frequency determined by master oscillator 2; With an increase in the relative duration of switching on J to –0.5, the block b performs a change in the logical control of the pulse interrupters 12, 1 12. K1; If earlier, 5 (the first control structure), the constant frequency pulses from the generator 3 are sent to turn on the pulse interrupters 12.1-12, N, and the latter are switched off when the current Id reaches the value of the current I, then at 7 0, 5 (the second control structure), the pulses of a constant frequency arrive at the switching off of the interrupters 12.1–12, KJ, and the switching on - during the sp-a. giving a current of 1 l to the value of I. Information about the magnitude of 1 l in pulsed form from converter 9 enters the inputs of blocks 7 and 8, Shaper 19 converts a pulse signal into a sawtooth voltage comparing with comparator 20 with RE voltage corresponding to current Iv, Trigger 21, which inputs pulses from the output of blocks 7 and 9, is set in opposite steady states. The output voltage of the coincidence circuit 22 corresponds to O. When the pulses are output from the output of the block 7), the flip-flop 21 is set to one steady state, and the voltage pulses are output to the output of the 8p block. . Thus, an on-time occurrence of voltage pulses at the outputs of blocks 7 and 8 is eliminated. In the absence of a current of 1 / J, the converter 9 generates voltage pulses with an initial frequency. In this case, the pulses and. (Fig. 2) of block 7 have duration, prrpo {natural current | y the voltage U o of the block 8 permits the charge of the storage capacitor of the integrator 18. The voltage Ug at the output of the latter exceeds the reference voltage Ug of the comparator 17 and at Uo O from its output the generation of pulses ° ° P ° P ° ® is forbidden register 15 is equal to 1, and the voltage at the control inputs of the interrupters 12.1 - 12. N have zero potential. On the perboy control structure (, 5), the pulses of a constant frequency from the generator 3 are fed through block 5 to the first input of the trigger U (voltage Ug-), and set it to one stable state. The voltage U7 from the direct output of the trigger 1O is fed through the amplifier 11 to the control input of the first chopper 12.1. Current 1L and frequency of impulses, gene-. increased by converter 9. When the current id reaches the value of r j-Udblock 7 stops the formation of pulses U. At the output of block 8, a pulse appears (Jg i which through block 5 enters the second input of trigger 110O (voltage OJ. Sets it to the opposite steady state. Control voltage of interrupter 12.1 decreases to zero according to signal Uy The current 1 and the frequency of the converter 9 decrease to the frequency at the first input of the trigger 1O of the fixed frequency pulses (Jj. This trigger 10 is set to the initial state and at U7 l. The interrupter 12.1 opens. Next, the described process repeats. At increasing T 0,5 block .3; pos left of the impulse (J performs the switching of the logic elements of block 5. In this case, the pulses Uc are switched from the first to the second input of the trigger 10, the Urt pulses are disabled from the block 8, and the permission to pass the pulses U; f to the first trigger input 10 Consequently, when changing the control structure of the chopper 12.1 (5 to D 0.5), the current Cor. Ijl passes the value of the setpoint current | and increases until the pulse trigger 10 arrives at the second input (J from the driver 3. The trigger 10 is set to the opposite is true the current state and the voltage UT 0 through the amplifier 11 closes the converter 12.1. The current -1 and the frequency of converter 9 decrease and when the first one drops, block 8 stops the formation of pulses U. At the output of block 7, a pulse U i appears which through block 5 enters the first input of the trigger 1O (voltage (J) its initial state. The voltage Uy 1 through the amplifier 11 opens the breaker 12.1. The current -i and the frequency of the transducer 9. increase until the trigger 10 (voltage U) of the pulses Uj arrives at the second input. regulating the current of the frequency of the probe, 5 is repeated. at a time, the constant frequency of current regulation when changing is forced by forcibly turning on the interrupter 12.1 at 2 0.5 and turning off at 0.5. If pulses U are received from the output of block 8, the previously charged storage capacitor of the integrator 18 is discharged and voltage (Jg from its output becomes less than voltage (J of comparator 17. Voltage (J takes a value equal to 1, however voltage 0, at the output of one-oscillator 16 retains a value equal to O, since it is triggered by falling edge of pulse Od. When Xtnax is increased, the pulses are U; (the outputs of block 7 are prohibited by the zone of blocking pulses. The inputs of trigger 10 receive pulses (J and Ul respectively, opening the interrupter 12.1. Regulated current 1 is not maintained at the set current level and when 1- | block 8 stops generating pulses O / j. The voltage of the output voltage of the integrator 18 increases with the voltage UD as well (Jn O. A single vibrator 16 generates a pulse that discharges the accumulator capacitor of the integrator 18 and switches the trigger circuit of the block 6. At the same time, the first output register 15 forms O, allowing for the permanent switching on of the interrupter 12.1 and the passage of pulses (Jj through the amplifier 11 to the control point of the second interrupt 12.2. Since the value of the nominal supply voltage of the engine 14 is raziit at N intervals, the voltage UJ / 1 on it, when Uy I (driver 12.2, on) is doubled, the Current i increases, and when -1 is byce of block 8, pulses of Yy are generated. They arrive at the second input of the trigger circuit of block 6, whose output signals, the logic elements of block 5 establish the first structure at board (0,5). The next step is the same as described in the process of adjusting the current i / i at the level of magnitude (m. With a further increase in motor speed 14, the output signals of register 15 step-by-step turn on 12.3, 12.4, etc., of breakers, and the chopper 12. W ensures the maintenance current l / i at a given level. Thus, as can be seen from the operation of the device, as a result of the phased switching-on (and -l) of the interrupters in the function and periodic switching of the N interrupter with the frequency of the master oscillator, the voltage U on the motor is described as with the expression: M. ,, ..., - ei ... u ;;; Ts-b (-t) T. where and, (i,., .., ON is the output direction of the interrupters 12.1, 12.2, ..., ..-. 12bL, / у- у - relative duration of switching on and period of switching-over of the breaker, H. Consequently, the instantaneous value of the voltage on the load approaches the analog form, which ensures the quality of the controlled current, in particular reduction of current ripple. In addition, the proposed device provides an extension of the range of speed control by decreasing by a factor of N the minimum possible of voltage values. Claims An apparatus for controlling a direct current electric motor, comprising a power supply unit and a generator, driving pulses, connected via blocking and delayed pulse drivers to the inputs of the switching unit, other inputs: which are connected to the outputs of the structure changing unit, comparison unit and inversion unit, connected with a pulse current converter core, the outputs of the switching unit are connected via a trigger to the structure changing unit, to the other input of which the shaper is closed Trigger pulses, the trigger output is connected to an amplifier included in the control circuit of a pulse interrupter, distinguished by the fact that, in order to improve the quality of control and extend the range of speed control, it additionally introduces (y - i) specified pulse breakers and distribution diodes. moreover, the outputs of iglpulsny interrupters through separating zioa are combined and connected. to the breakout of the main motor trimming, the second output of which is connected to the power supply unit, serially connected shift registers, one-shot, comparator and integrator, the input of which is connected to the inversion unit, the shift register is connected to the amplifier, whose outputs are connected to control inputs of pulse devices, single-shot output connected to other inputs of the integrator AND the block change structure. Sources of information taken into account during the examination 1. USSR author's certificate MI 395296, .kl. BOO 15/04, H 02 P 5/16, 1972. 2. USSR author's certificate number 481476, cl. B 60 L 15/04, H 02 P 5/16, 1976.  sp vr7v74 - IS 22 -d I FIG. and imr innnnn i} U, P ,, P P Ub , 4VUMWMt M / M WM.iM ( I / O I I I r% P I