A Novel Screw-Based Probe to Measure Pulse Forming Line Voltage in Tesla-Type Generators

A novel screw-based probe is put forward to measure the pulse forming line (PFL) voltage in Tesla-type generators. This probe utilizes an existing screw as the key part of the conventional probe. Therefore, no extra hole is needed, which simplifies the design of the PFL. The voltage ratio of this probe is not a constant which varies within the pulsewidth with a deviation of ±5%. By analysis, it is found that this deviation is mainly due to the complicated electromagnetic environment on the outer magnetic core of the Tesla transformer where this probe is assembled. The electromagnetic environment can cause perturbation which adds on the main test waveform when the Tesla transformer is charging. Two solutions are proposed for this question. One is to consider the voltage ratio as a time-dependent variable, rather than a constant any more. The other is to redesign the screw-based probe and assemble it where the electromagnetic environment is weak. Both the methods can decrease the deviation of the voltage ratio to a level smaller than 1% and are applied in practical measurements.