DC System Ground Fault Testeris used to locate the exact position of ground faults in DC systems of power plants and substations without power interruption. This instrument introduces a brand-new detection method in principle - waveform analysis method. Its main features and advantages: high detection sensitivity, strong ability to eliminate distributed capacitance of the system, detection without power interruption, no impact on normal system operation, strong anti-interference capability, safe and reliable, etc.
The waveform analysis method is to add a specific periodic voltage signal between the DC bus and ground, detect the current of each branch through a clamp-type probe, analyze and calculate the phase and phase difference of the fundamental wave and harmonics of the current signal, and then determine whether there is a ground fault and the location of the ground fault point.
This device consists of three parts: signal generator, signal receiver, and signal collector (clamp). When locating faults in DC systems, all three must be used together.
This signal generator does not use traditional LC or RC oscillator circuits, but adopts a brand-new digital technology, thus having the characteristic of stable signals. The signal generator consists of a microcontroller, A/D conversion circuit, signal amplification and filtering circuit, power amplification and DC blocking circuit, output feedback and protection, etc.,
