SU1339858A1 - Multimotor a.c. electric drive - Google Patents

Abstract

The invention relates to electrical engineering, can be used in automated electric drives of conveyors of drawing mills. The purpose of the invention is to improve the control accuracy and to provide a predetermined ratio of rotational frequencies of asynchronous motors. The motors are controlled by a reference frequency generator, the output of which is connected to individual control units connected to the control inputs of the regulator. 2 Il. 00 00 CO 00 CL 00

Description

113398582

 The invention relates to electric regulator 2 in rotary circuits of the asyn-technique and can be used in synchronous electric motors can be automated electric drives made in the form of thyristor rectifier conveyors, drawing mills, and so on. A body whose output has been shunted by the re- ation of the invention is an increase by a sistor.

The following conventional ratios of rotation frequencies are taken in Fig. 2: 14 and 15 are the voltages of respectively asynchronous electric motors. Figure 1 shows the structure of the rectangular pulses at the input and output; 16 and. Device circuit; 2 - time-17 - voltage at the first corresponding voltage diagrams. In particular, the input and output of the RS flip-flop; 18

Multi-motor electric drive 19 - the voltage at the outputs of the corresponding alternating current contains asynchronously the second logic element

electric motors 1 with a phase roto-152I and controlled divider 10 by a separator, in the circuit of the rotor windings of which they are; 20 and 21 - output voltages

included are the controllers 2, which control the counter and the inverter respectively;

the inputs of which are connected to the outputs 22 - the voltage at the output of the third

control blocks 3, the inputs of which are the logical element 2I. connected to block 4 tasks, which 20 The device works as follows as a generator this time.

When the engine 1 is turned on into a network of laziness is made up of a differentiating side of the stator, the engine starts link 5, the first logical element works on the adjusting characteristic 2 and 6, the RS flip-flop 7, the second logic defined by the size of the resistive element 2И 8, the torus shaper in the rotor chain. At the output of 9 rectangular pulses, the controller of the 9 rectangular pulses of the frequency divider 10, the counter is 11 rectangular positive, inverter 12, the third logical pulses (figure 2), coming from element 2I 13, the output of a formatizing differentiating link 5 for the first 9 rectangular pulses is the input terminal of the logic element 6, which is connected to the inputs of the inverter 12 and the differential section passes these pulses to the input of the coding link 5, the output of which RS-trigger 7, provided that it is connected to one input first The last one is in the initial state element. 2I 5, the output of which (. nii (1 at the second output of the trigger 7) is connected to one input RS-As a result of the occurrence of two trigger signals, the second input of which Under-on inputs of the logic element 8, this is connected to the output of the counter 11, the input of the bell-shaped impulses of the generator 4 passes through it connected to the output of the controlled-through logic element 8 to the input frequency divider 10, the input of which is often controlled by the code 10 divider - connected to the output of the second logic that divides the specified frequency element 2 and 8, one input which has a certain coefficient, for example, is connected to one output of an .RS-trig-measure, by 2, as a result of which on its 7, the other output of which connects the output the other input of the first logic pulses, which is fed to the input element 2 and 6 and to the control meter 11 with a fixed capacity, the input of the controlled divider 10 is often-At the moment of overflow of the counter 11 by you, the output of the inverter 12 is connected to the code , to one input of the third logical one throws the trigger 7 into the 2I 13 unit, the other input of which is 50 one position, relieving the voltage is connected to one of the RS-flip-17 and 18 codes (Fig. 2). The pulse duration, another input of the second logic voltage of the voltage 17 determines the driver element 2I 8 forms the input of the 3-signal unit of the rotation frequency of the control motors, the output of the third logical-1-n, the change of the setpoint of the given frequency element 2I 13 forms the output of the block rotational torques can be achieved by a 3 control, the input of the generator, both by changing the coefficient 9 of the rectangular pulses, forms a division of the frequency divider 10, and into the information input of the control block 3, the result of the change in the tracking frequency. generator pulses

4 high frequency. In both cases, the filling time of the counter 11 is changed in the right direction and, therefore, the duration of the driving signal is changed. By changing the frequency of the pulses of the generator 4, the driving signal for all engines is changed, and by changing the division factor of the controlled splitter 10 frequency, the driving signal for each of the engines is made individually.

If the duration of the pulse 15, which characterizes the actual rotational speed, is less than the duration of the master signal 17, the output of the logic element 12 appears to turn on the regulator 2, as a result of which the rotational speed of the engine 1 and, therefore, the duration of the voltage pulses 17 increase to of the preset level. In the next period of time (Fig. 2), the pulse 22 for switching on the regulator 2 is not detected at its control input.

Thus, the use of a generator of the reference frequency, the output of which is connected to the inputs of the control units of the regulators, makes it possible to increase the accuracy of controlling the frequency of rotation of the engines and to maintain the specified ratio of the frequencies of rotation.

Claims (1)

Invention Formula A multi-motor electric drive containing alternating current asynchronous motors with a phase-rotor, in the circuit of the rotor windings of which a controller is connected, the control input of which is connected to the output of the control unit whose input is connected 5 about 5 about five g To the task block, the information inputs of the control unit are connected to rotary circuits of induction motors, characterized in that, in order to improve the control accuracy and to ensure a predetermined ratio of the rotational speeds of the induction motors, controllers and control units for each asynchronous motor are entered into it; made in the form of a master frequency generator; the control unit is composed of a square pulse generator, three logic elements 2I, an RS flip-flop, a differentiating link, controlled frequency divider, counter, inverter, output of the square pulse generator connected to the input of the inverter and the differentiating link whose output is connected to one input of the first logic element 2I, the output of which is connected to the input of the RS flip-flop, the second input connected to the output a counter whose input is connected to the output of a controlled frequency divider, the input of which is connected to the output of the second logic element 2I, one input of which is connected to one output of the RS flip-flop, the other output of which is connected To the other input of the first logic element 2I and to the control input of the controlled frequency divider, the output of the inverter is connected to one input of the third logic element 2I, the other input of which is connected to one output RS of the flip-flop, another input of the second logic element 2I forms the input of the control unit, the output of the third logical 2I element forms the output of the control unit, the input of the rectangular pulse former forms the information input of the control unit. / - / ln j-g 3-. Editor L.Gratillo Compiled by V.Aleshechkin Tehred L, Serdyukov Proofreader A.Obruchar Order 4243/54 Circulation 659 Subscription VNSHPI State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4