Mutual inductance type contactless starter used for single-phase alternating current motor

Abstract

The invention discloses a mutual inductance type contactless starter used for a single-phase alternating current motor, which is used for starting a compressor motor, a common single-phase alternating current induction machine or a single-phase alternating current permanent-magnetic motor. The starter comprises a current transformer L which comprises a primary coil and a secondary coil, a bidirectional triode thyristor T and a positive temperature coefficient thermistor PTC, wherein one end 1 of the primary coil of the current transformer L and one end of a power supply end are connected withone end of the positive temperature coefficient thermistor PTC; the end 2 of the primary coil of the current transformer L is connected with a main winding leading-out end M of the motor; the end 3 of the secondary coil of the current transformer L and a first electrode A1 of the bidirectional triode thyristor T are connected with the other end of the positive temperature coefficient thermistor PTC; the end 4 of the secondary coil of the current transformer L is connected with a trigger electrode G of the bidirectional triode thyristor T; and a second electrode A2 of the bidirectional triode thyristor T is connected with the leading-out end S of the secondary winding of the motor. The mutual inductance type contactless starter used for the single-phase alternating current motor has the advantages of improving energy conservation efficiency and improving the reliability of a motor startup system while ensuring the startup function of the motor, along with simple circuit and few elements.

Description

technical field [0001] The invention relates to a mutual-inductance non-contact starter for single-phase AC motors, which is mainly used for starting compressor motors, and can also be used for starting common single-phase AC induction or single-phase AC permanent magnet motors, as follows Collectively referred to as single-phase AC motors. Background technique [0002] A single-phase AC motor usually consists of a rotor and a stator consisting of primary and secondary windings. In addition to the function of starting the motor, the auxiliary winding can also continue to work when the motor is running normally, so the auxiliary winding circuit of a complete single-phase AC motor can usually be represented by a parallel auxiliary winding running circuit and auxiliary winding starting circuit . When the motor is running normally, the motor whose auxiliary winding does not participate in the work does not have the auxiliary winding running circuit part. Among them, the start...

AI Technical Summary

Problems solved by technology

Resistors are purely resistive components, and the current of the total circuit of the motor is usually at or near the ampere level, so that during the entire operation of the motor, the resistor consumes useless heat dissipation at or near the watt level

This circuit also greatly reduces the utilization rate of energy while being able to start the motor

In addition, the circuit uses auxiliary circuits such as "reference current setter" and "comparison circuit". The existence of these auxiliary circuits reduces the reliability of the motor starting function to a certain extent.

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