Novel mutual-inductance contactless starter

Abstract

The invention relates to a novel mutual-inductance contactless starter, which is used for starting a compressor motor, a common single-phase AC inductance motor or a single-phase AC permanent-magnet motor. The starter comprises a current transformer L comprising a primary coil and a secondary coil, a bidirectional thyristor T and a positive temperature coefficient thermistor PTC. The end one of the primary coil of the current transformer and one end of a power supply end are connected with one end of the positive temperature coefficient thermistor PTC. The end two of the primary coil of the current transformer L and the end four of the secondary coil are connected with the leading-out end M of the main winding of the motor. The end three of the secondary coil of the current transformer L is connected with the trigger electrode G of the bidirectional thyristor T. The first electrode A1 of the bidirectional thyristor T is connected with the other end of the positive temperature coefficient thermistor PTC. The second electrode A2 of the bidirectional thyristor T is connected with the leading-out end S of the secondary winding of the motor. The invention has the advantages that the energy saving efficiency can be improved; and the circuit is simple, the number of the components is less, the components are reliable, the starting function of the motor is ensured and the reliability of the motor starting system is improved.

Description

technical field [0001] The invention relates to a new type of mutual induction non-contact starter, which is mainly used for starting compressor motors, and can also be used for starting ordinary single-phase AC induction or single-phase AC permanent magnet motors, hereinafter collectively referred to as single-phase AC motor. 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 starting circuit pa...

AI Technical Summary

Problems solved by technology

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