Recent Developments on Generator Excitation Control System

OVERVIEW: In recent years, the scale of power systems has been expanding, and with that expansion stable power supply and smooth power system operation is becoming increasingly important. In particular, because system stability tends to decrease as the power system moves toward higher capacity and longer distances in power transmission and wider-area operations, and as the constant power, non-linear load generated by air conditioners and other such equipment increases, ensuring and increasing power and voltage stability becomes an even greater problem. One measure for increasing stability is to improve the main circuits by raising the voltage or employing series capacitors in power transmission lines, but the generator exciter control method, which makes use of a CD-AVR (compact digital automatic voltage regulator), PSS (power system stabilizer) and PSVR (power system voltage regulator), is attracting attention because of its high cost advantage. Hitachi, Ltd. has implemented these generator exciter controls with the HIACS-7000 System, which uses the latest 32-bit RISC (reduced instruction set computer) processors, to realize a practical high-speed, highly reliable exciter system that is suitable for stable operation of a power system. Yoshihiro Kitauchi Takashi Shirasaki Kunitaka Hayashi Minoru Banjo Satoshi Kitamura