Unit measuring potential separate current at 3=phase asynchronous motor inverter - determines current in intermediate circuit across shunt and is compensated corresp. to fluctuations in current circuit

摘要

The measurement value determination lies at the intermediate circuit potential. The potential separation is carried out across a voltage frequency converter in conjunction with a light conductor transmission. The digitally processed measurement signal allows synchronisation with external controls. The current is measured directly across a shunt instead of the known current transformer. ADVANTAGE - Voltage fluctuations in intermediate circuit have no influence on current value determination and high protection against interference is achived. Signal transmission is also free of electromagnetic and HF interferences.