Frequency Measurement of the Automatic Generator Quasi-synchronizer Based on SCM and CPLD

The quasi-synchronizing parallel is an important operation in the power system. If the frequency error is too great, the oncoming generator could slip a pole, causing damage to the machine. Therefore, the precision frequency measurement of the generator and the power system is one of important conditions to ensure that the automatic quasi-synchronizer can operate accurately. A new method of frequency measurement used in the generator automatic quasi-synchronizer is discussed in this paper. The basic principle of the frequency measurement is introduced. The frequency measurement is finished by combining SCM and CPLD (complex programmable logic device) technique. CPLD detects the frequency and the SCM manages the data and implements intelligent control, the hardware circuit diagram and the software flow chart are showed in the paper. The experiments indicate that the measurement precision and system integration are improved. The measurement error is less than 10^-3 and the novel quasi-synchronizer is practical.