Ground Impedance Tests
In order to simulate a single-phase fault, a test current is injected into one of your power lines by using a frequency variable current source and grounding the remote end of the line. Then, you measure the voltage between the grounding system and a spike driven into the soil close to the fence around a substation. You repeat this measurement by increasing the distance between the spike and the grounding system until the voltage is not increasing any further. The voltage of the last measurement location is now calculated up to the ground potential rise under real fault conditions.
For suppression of interferences, conventional test methods use high power injection at the mains frequency. You can freely select the frequency with our system. Injecting a signal with a frequency higher or lower than the mains frequency and applying a steep filter suppresses the interference effectively. Our test systems use this technique and allow you to inject much smaller currents for gaining accurate measurement results.