A non-arc power failure protection switch control circuit

Abstract

A control circuit for a non-arc power failure protection switch, comprising: a first switch, a second switch, a first delay circuit, a first controllable switch, a second controllable switch, a second delay circuit and a thyristor circuit; One end of the first switch is connected to the live wire of the power supply, and the other end is connected to the load; the first delay circuit is used to rectify the output of the power supply and control the on-off of the second controllable switch; the second delay circuit is used for To control the on-off of the first controllable switch, and the time constant of the second delay circuit is smaller than the time constant of the first delay circuit; the second switch is connected to the second input of the second delay circuit Between the end and the neutral line; the thyristor circuit is connected between the neutral line of the power supply and the load. The control circuit of the non-arc cut-off protection switch of the invention has the characteristics of long life, simple structure and low cost.

Description

technical field

[0001] The invention belongs to the field of electric switches, and in particular relates to a control circuit for a non-arc power failure protection switch. Background technique

[0002] At present, AC contactors generally use capacitors connected in parallel in the line as power factor compensation. This type of AC contactor has arcing and high surge current, and the compensation circuit is easy to break down, the service life is short, and the long-term operation cost is high.

[0003] Thyristor capacitor switching switch has the advantages of no surge when connecting the capacitor and no arc when breaking the capacitor. However, due to the problems of large conduction voltage drop, temperature rise, and large harmonic pollution, it has appeared on the market for this reason. A capacitive switching switch called a compound switch with a parallel structure of a thyristor and a mechanical contact has been introduced. It has the advantages of reduced voltage ...

Examples

Embodiment Construction

[0034] Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the terms "first", "second", "third", etc. herein, if present, are used to distinguish between similar elements and do not necessarily describe a particular order or chronological order order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the subject matter described herein are, for example, capable of being performed in an order different from that described herein or in another order described herein. operate. The term "connected" should be interpreted broadly and refers to electrically, mechanically, or otherwise connecting two or more elements or signals, either directly or indirectly through intermediate circuits and / or elements.

[0035] figure 2 Shows the structural block diagram of the non-arc cut-off protection switch control circuit of the embodiment of the pres...

technical field

[0001] The invention belongs to the field of electric switches, and in particular relates to a control circuit for a non-arc power failure protection switch. Background technique

[0002] At present, AC contactors generally use capacitors connected in parallel in the line as power factor compensation. This type of AC contactor has arcing and high surge current, and the compensation circuit is easy to break down, the service life is short, and the long-term operation cost is high.

[0003] Thyristor capacitor switching switch has the advantages of no surge when connecting the capacitor and no arc when breaking the capacitor. However, due to the problems of large conduction voltage drop, temperature rise, and large harmonic pollution, it has appeared on the market for this reason. A capacitive switching switch called a compound switch with a parallel structure of a thyristor and a mechanical contact has been introduced. It has the advantages of reduced voltage ...

Examples

Embodiment Construction

[0034] Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the terms "first", "second", "third", etc. herein, if present, are used to distinguish between similar elements and do not necessarily describe a particular order or chronological order order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the subject matter described herein are, for example, capable of being performed in an order different from that described herein or in another order described herein. operate. The term "connected" should be interpreted broadly and refers to electrically, mechanically, or otherwise connecting two or more elements or signals, either directly or indirectly through intermediate circuits and / or elements.

[0035] figure 2 Shows the structural block diagram of the non-arc cut-off protection switch control circuit of the embodiment of the pres...

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