A Microprocessor-Based PLL Speed Control System Converter-Fed Synchronous Motor

A microprocessor-based digital phase-locked loop (PLL) speed control system of a self-controlled synchronous motor fed by a current source inverter is presented. The hardware and software structures of the system are shown in detail. Sophisticated methods for synthesizing PLL control systems are proposed. Experimental results demonstrate the validity of the proposed methods. The minimum maintenance and the cost reduction can be expected by the use of this system.