DC fault arc detection and protection device

Abstract

The invention relates to a DC fault arc detection and protection device, and belongs to the field of electrical engineering. The device comprises a high-frequency current transformer, a Hall current sensor, an amplifier, a bandpass filter, a high-precision ADC, a digital signal processor (DSP) and an IGBT circuit breaker, an output terminal of the high-frequency current transformer is connected with an input terminal of the amplifier, an output terminal of the amplifier is connected with an input terminal of the bandpass filter, an output terminal of the bandpass filter is connected with an input terminal of an AD sampling circuit, an output terminal of the AD sampling circuit is connected with an input terminal of the digital signal processor, and an output terminal of the digital signalprocessor (DSP) is connected with the IGBT circuit breaker. A current signal obtains a high-frequency current component through coupling via the high-frequency current transformer, the signal is amplified by 10 times through the amplifier and then passes through the bandpass filter, the ADC samples the signal and transmits the signal to the DSP for algorithm processing, the Hall current sensor transmits a detected DC current value to the DSP for dynamic threshold calculation, and an arc is extinguished through the circuit breaker after detection of arc generation so that protection is realized.

Description

technical field [0001] The invention belongs to the field of electrical engineering and relates to a DC fault arc detection and protection device. Background technique [0002] With the continuous development of social economy, high-power power electronic devices have been widely used. What followed was the rapid popularization of DC systems in aerospace, solar power generation, and large-scale power grid energy storage. In a DC system, loose metal connectors, animal bites, and damage to insulation layers such as transmission lines may cause DC arcs. [0003] Since the DC fault arc does not have the zero-crossing characteristics of the AC fault arc, the arc is not easy to extinguish; in addition, when a fault arc occurs, especially when a series DC fault arc occurs, it is similar to a resistor connected in series, and the circuit current will drop instead, and cannot reach the circuit breaker and fuse. Therefore, these protective devices are powerless to protect DC fault a...

AI Technical Summary

Problems solved by technology

However, the existing time-domain analysis results of current and voltage are not necessarily caused by arc faults, and the accuracy needs to be verified.

The detection of arc light, arc sound, temperature, etc. has high requirements on the detection environment, and the installation position of the sensor is fixed, and the monitoring area is small, which is difficult to meet the application occasions of large outdoor DC systems

Images