UHV(H) Power Frequency AC Series Resonace Test System for CVT Calibration

 

 

 

 

1. Due to the full compensation of resonant reactive power, the power of the power supply and equipment is only less than 1/10 of the capacity required by the test product (1/Q>10); The same capacity is small in size, light in weight, the output capacity of the device is large and the power capacity of the required configuration is small, the price is low, and the operation is convenient and safe;

2. The series resonance is actually a current filter loop, so that the current passing through the test product is basically the fundamental current, and the waveform distortion rate (THD) of the output voltage is extremely small, which is better than all types of existing AC withstand voltage equipment;

3. The short-circuit current after flashover or breakdown of the sample is only less than 1/10 of the test current before the short circuit (1/Q), which can effectively prevent the expansion of damage to the fault point after breakdown;

4. Immediately after flashover, the arc is automatically extinguished, and the process of restoring the resonant state voltage establishment after arc extinguishing is long (seconds) is a steady-state establishment process, and there is no concern about voltage overshoot, nor the danger of recovery overvoltage in the microsecond-level millisecond-level transient process.

 

 

 

 

 

 

 

Q: What is a capacitor voltage transformer CVT or CCVT construction and working?
A: Capacitor Voltage Transformer (CVT) or Capacitor Coupled Voltage Transformer (CCVT) is a switchgear device used to convert high transmission class voltage into easily measurable values, which are used for metering, protection, and control of high voltage systems.

Q: What is CVT calibration data?
A: CVT data are figures which are determined in one of the final routine tests in factory and stored in SCEM board of N, U, W, RL series. For E series, it is stored inside the ADVC3 controller which is paired with the switchgear at time of the CVT calibration tests are conducted.
Due to manufacturing errors of electronic components and bushings, CVT data is unique to every bushing and SCEM (where installed) combination.
Therefore, for N, U, W and RL series replacement of SCEM may cause voltage readings to be incorrect. In such cases, voltage measurement can be recalibrated by first reloading the latest CVT data file, then adjusting voltage reading using the Calibration menu on WSOS software. Refer to the on-site CVT Calibration procedure for more information.