SU824382A1 - Thyratron electric motor - Google Patents

Description

(54) VENTILATION ELECTRIC MOTOR

I

The invention relates to electric machines of automation systems and can be used in devices and devices that require high reliability and energy performance, where engines with high speed, low and medium power, with half-wave switching devices are needed.

A device is known that contains a t-phase synchronous maschine, a semiconductor switching unit, a diode and a zener diode, and the maschine phases are connected to the outputs of a semiconductor switching device, which, in turn, are connected to the common point of the phases of the engine 1 through diodes.

 The disadvantages of a valve motor (VD) are the relatively low frequency properties (due to the properties of the Zener diode) and the presence of large losses in the shunt circuit, which limits its scope.

The closest in technical essence and proposed is a device containing a rotor, a stator with a winding core, one of the clamps of each of the m sections is connected to the power circuit of the switch key, and the second clamps are combined, and a protective device connected in parallel to the winding sections of the switch 2

The disadvantage is the presence in the engine of a large number of power closing dinistors, which, in turn, have a large variation of parameters, low frequency properties and can switch a relatively low power.

. The purpose of the invention is to increase reliability by effectively protecting the power switches of the switching device from overvoltage.

Claims (2)

The goal is achieved by the fact that the protective device contains m differentiating chains, each of which consists of a series-connected capacitor and a resistor, 2t diodes and a discharge device made in a series-connected transistor and resistor, with the output of each of the differentiating chains connected through a diode the control circuit of the key, and the bit chain is connected to the common point of the sections directly, and to the common point of each of the keys and the section through a diode. The drawing shows a circuit diagram of a three-phase VD. Phases 1-3 of the motor are connected according to a star with zero, the zero end of which is connected to the power source, and the other ends of the phases are connected to the outputs of semiconductor power transistor switches 4-6 of the switching device, which in this case are selected transistors. Differentiating circuits consisting of capacitors 7-9, resistors 10-12 and diodes 13-15 with their inputs (inputs of capacitors 7-9) are connected to collectors of transistor switches 4-6. Moreover, the outputs of the diodes 13-15 are connected and connected to the control input of the key transistor element 16, one power circuit terminal of which is connected to the "zero phase of the motor, the second terminal is connected to the second electrode of the limiting resistor 17, the first electrode of which is connected to the integrated cathodes diodes 18-20, the anodes of which are connected to the collectors of the corresponding semiconductor power transistor switches 4-6. The device works as follows. When the motor is connected to the power source, the semiconductor power switches alternately connect the corresponding phases to the Un power supply, according to signals from the rotor position sensor, coming to the bases of transistor switches 4-6, at the time of locking the semiconductor power switches 4-6 on them due to the emf of self-induction phases 1-3, an overvoltage occurs, which can reach significant magnitudes and disrupt key elements. This reduces the reliability of the entire device. Let key 4 is open at the initial moment and current flows in phase 1. In this case, the capacitor 7 is charged along the circuit .. + Un - resistor 10 - capacitor 7 - collector-emitter junction 4 - {-U). In this case, the element 16 is locked. When locking key 4, capacitor 7 is discharged along the circuit; capacitor 7 - resistor 10 - phase 1, which leads to the formation on the resistor 10 of a voltage of such magnitude and polarity that the closing transistor element 16 is unlocked and the current from the EMF self-induction phase closes along the circuit + EMF self-induction phase 1 - diode 18 - resistor 17 - transistor 16 - (-EMF) self-induction of phase 1. Thus, the introduction into the device of differentiating chains connecting the phases of the motor with the key element in a certain way, makes it possible to economically and effectively eliminate overvoltage on the power switches of the switching device either limit the surge voltage at a predetermined level, which can be controlled by a limiting resistor 17. Formula of invention A valve electric motor containing a rotor, a stator with a winding core, one of the clamps of each of the m sections of which is connected to the switch circuit's power circuit, and the second clamps are combined and a protective device connected in parallel to the core winding sections, characterized in that, in order to increase reliability, the protective device contains m differentiating chains, each of which consists of The sequence connected capacitor and resistor. , 2t diodes and a discharge device made in the form of a series-connected transistor and a resistor, with the output of each of the differentiating chains connected via a diode to the control circuit of the key, and the discharge chain connected to the common point of the sections keys and sections - through the diode. Sources of information taken into account in the examination 1.V. Balagurov et al. Non-contact DC motors with permanent magnets. M., “Energie, 1975, p. 23. 2. USSR author's certificate number 420057, cl. H 02 K 29/02, 1974.