SU913536A1 - Device for control of single-phase induction electric motor - Google Patents

Description

The invention relates to electrical engineering and can be used for starting and braking single-phase asynchronous electric motors with a short-circuited rotor, having a starting winding or a starting capacitor, which are disconnected at the end of the start.

There are known devices for controlling a single-phase asynchronous motor, which contain a bipolar switch for connecting a working winding and a winding to a network, and a declining chain Γΐ].

This device provides the start and braking of electric motors of only low power, which is its disadvantage.

'The closest to the proposed technical essence and the achieved result is a device for controlling a single-phase asynchronous electric motor (BP), which provides engine start and braking. The device contains a bipolar switch 2

a two positions, with the help of the first contact of which the working winding HELL is connected to the network, and with the help of the second contact the winding of the electromagnetic relay through the time-dropping circuit ⁵ and the rectifier diode. The closing relay contact provides connection of the start winding of the HELL to the network through the fa - e-shifting element and the switch in the working winding circuit. An additional rectifying diode, a shunt switch in the circuit of the operating winding, serves to supply the motor windings with rectified network current through the closing contact of the relay when disconnecting the circuit from the network with switch G 21. ·

A disadvantage of the known device is the complexity due to the presence of two diodes having a low coefficient

„Use.

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The purpose of the invention is to simplify the device.

This goal is achieved by

that one clip of the second contact ne

5 4

in total, the operating time of the AD, contacts 7 are open, and contacts 10 of relay 3 are closed due to the presence of a charged capacitor 6.

When BP is disconnected by switch 1, the motor windings 2 and 8 are connected in parallel and flow around the rectified network current through diode 5, switch 1 contacts, and closed contacts 10 of relay 3. BP decelerates rapidly. At the end of the discharge of the capacitor 6 to the winding of the relay 3, the latter opens its contacts 10 in the circuit of diode 5, thereby breaking the power supply circuit of the engine <5 current 2 and 8 of the engine with the rectified network current. The process of inhibition of blood pressure is over.

Thus, the introduction between the relay contact and the diode contact switch provides the use of _single-m Nogo the same rectifier diode not only for starting blood pressure, but also for dynamic braking, which simplifies the apparatus, increases its reliability and reduces cost.

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Claims (1)

Claim Device for controlling single-phase asynchronous electric motor with ₃₀ working and starting windings, containing a relay, the closing contact of which is connected in series with the diode, and the opening contact - to the starting winding circuit, resistor and capacitor, which is connected in parallel with the working winding of the relay ³³ , two-pole switch, first contact which is connected to the working winding, and the second one is connected to the diode, shunting the first contact of the switch with one clip, characterized in that, for the purpose of simplification, one clip of the second contact across yuchatelya connected to the cathode of a diode in series with a normally open relay contact, and the second - to a resistor, Cpd ⁴⁵ nennomu series with the parallel-connected run winding turnips and a condenser and the other end of this parallel connection is connected to the common connection point and the working pus5® kovoy winding.