Problems of voltage transducer in harmonic measurement

If the neutral point either on primary or secondary side of potential transformer is not grounded directly, the harmonic voltage measurement will not reflect the real distortion of the system voltage. Also, capacitive voltage transformer on high and medium voltage system cannot be used for harmonic voltage measurement. A new method to set the voltage signal from the tap of Current Transformer bushing is recommended here. The recommended method can achieve a more precise result of harmonic voltage measurement.