Development of microcontroller based controller for twelve-pulse AC-DC thyristorised converter for nuclear research application

Controlled high current converter systems are extensively used in experimental test facilities for simulating the nuclear fuel clusters by electrical heating. Nuclear Fuel Cluster Simulators have been heated by I2R method using controlled DC current to simulate the power or temperature profiles in experimental test facilities for nuclear research. In order to simulate a desired power profile, the set point of current is changed with respect to time. The capability of AC-DC converter system to maintain the set output current irrespective of any changes in input voltage and/or load resistance is critical for these applications. The paper presents design & development of microcontroller based controller for controlling the output DC current of twelve-pulse 600 kW AC-DC thyristorised converter. The controller is implemented incorporating a microcontroller, current feedback signal from DC Current Transducer, synchronization signal and current set-point controlling the output DC current in close loop system.