Microprocessor control of double output induction generation. I. Inverter firing circuit

The design and implementation of a firing scheme using the INTEL 8086 microprocessor to control the inverter firing angle of the variable-speed constant-frequency double-output induction generator (VSCF-DOIG) are described. The microprocessor is used to control the phase shift of the DC-linked inverter of the VSCF-DOIG. It computes the voltage signals from a reference voltage potentiometer and then outputs the calculated firing-angle shifting time (as opposed to deriving it from a table lookup method) to the interface timer. This gives full-range control of the firing angle between 0 degrees and 180 degrees , and updates the phase-shifting timer in each cycle on the basis of the values of the previous three cycles. The control circuit is designed for multitask purposes. The hardware, software, interface, input/output, and experimental results are presented.<>