How to correctly observe the high-speed pulse of AC power supply problem

When AC power supplies measure high speed pulses with rise times and pulse widths of nanoseconds, it is necessary to prepare an AC power oscilloscope with a large band width and a large number of samples. If the output impedance of the object device is a coaxial structure with a level of 50Ω, the AC power oscilloscope and pulse generator can be directly connected by using a coaxial attenuator and coaxial cable. With this observation method, the object waveform can be observed in the AC power supply state with low loss and low delay.

500kW load bank
 

In general, the specifications of the equipment called AC power generators are determined by international standards, regional standards, manufacturer standards, etc. Almost all AC surge generators do not have a coaxial 50Ω output. Since the terminal shape is not the 50Ω level of the coaxial structure, the waveform observation requires the use of a differential probe and a passive probe. In observation methods using AC power differential probes and passive probes, the same values as the calibration data of the tester (data from the test sheet) may not be observed. The advisory content of "different from the observed result" is almost all the waveforms containing the rising edge and pulse width of "ns" ~ "μs". Due to the lack of adjustment, the AC power supply has different observations.

The consultation situation when the differential probe is used to observe the AC power waveform mainly includes:

Oscilloscopes and probes are recommended for aviation allowance power supply, but correct waveforms cannot be observed.

The probe has been calibrated by the aeronautical power supply, but the observations are inconsistent.

Alternating power oscilloscope with the same frequency width, but the observation results are completely different.