Method for the measurement of rotor voltage and current of power generator

A method to measure rotor voltage and current in power generator is described in this study. The system is based on analogue to digital conversion and optical fibre transmission principle. The voltage and current signals from the semiconductor controlled rectifier (SCR) bridge of the power generator are conditioned to proper amplitude for the A/D converter's (ADC) input and then the digital signal from the ADC is transmitted to the local module through optical fibre. The power consumption of the circuitry in the remote module is about 50 mW and the power efficiency of the optically powered supply at the high-voltage side is about 76%. The uncertainty of the electronic instrument transducer (EIT) developed in this study is estimated to be less than 1.1% in ratio and the delay time of the step response is less than 7 ms.