Non-electrical restarting circuit and driving method

Abstract

The invention discloses a non-electrical restarting circuit, which comprises a starting unit, a load unit and an output unit, wherein the starting unit consists of a starting relay, a capacitor and a diode; one end of a circuit formed by connecting a coil of the restarting relay, the diode and capacitor in parallel is connected in series with another diode and a resistor and then connected with one end of a direct current power supply, and the other end of the circuit is connected with the direct current power supply; the load unit is formed by connecting the resistor in series with a normally closed contact of the starting relay; the two ends of the load unit are also connected with the direct current power supply; the output unit is formed by connecting an output relay and a normally open contact of the starting relay in series; and the two ends of the output unit are also connected with the direct current power supply. The non-electrical restarting circuit is used for non-electrical protective restarting in the relay protection of a power system, and can effectively control operating voltage, improve starting power and avoid false operations caused by the input of alternating current voltage.

Description

technical field [0001] The invention relates to a non-electricity resetting circuit and a driving method in electric power system relay protection, and a non-electricity protection device adopting the circuit. Background technique [0002] Main transformers and reactors operating on industrial sites are generally required to be equipped with non-electrical protection such as gas protection, pressure release, and over-temperature protection. Most of the non-electricity protections are installed outdoors. In rainy weather, the cables are likely to be damp and the insulation is reduced, causing the cables to be grounded, making the loop input voltage reach 50% of the rated DC power supply voltage, and causing protection malfunctions. In addition, during on-site wiring by construction workers, misconnecting the AC line into the circuit due to operational errors will also cause malfunction. Misoperation of protection may cause large-scale power outages and cause unnecessary loss...

AI Technical Summary

Problems solved by technology

The above two methods have the following problems: 1) Due to the discreteness of the intermediate relay, it is difficult to control the operating voltage in the range of 55% to 70% of the rated DC power supply voltage; 2) It does not meet the requirement of adding 220V AC voltage and not operating; 3) The first method has low starting power, which is easy to cause misoperation; although the second method increases the starting power, it is difficult to reach 5W, and the load is not cut off after starting, so that the power generated under the rated voltage is much greater than the starting power. The heat generated is very large, and it is easy to burn components and printed boards after long-term operation, and bring hidden dangers to safety

Images