The Design Of Field Regulator For Hydraulic Generator

The excitation control system for synchronous generator plays an important part in the function process of electricity power system . Not only it controls the terminal voltage of the generator, but also controls some other parameters of the generator like reactive power, power factors, currents, etc.. When the electricity power system runs correctly, the excitation control system maintains the voltage of the generator and the whole system, distributes the wattless loads equitably over the generators, improves the steady-state stability and the dynamic stability of the electricity power system. This dissertation mainly investigate the field control for hydraulic generator.The excitation control system not only ensures the reliability and the stablity of the generator, but also effectively improves the technical enonomy index of the generator and the electricity power system which it connects with. With operating the excitation control system with PLC, this design maintains the terminal voltage of the generator and the whole system, distributes the wattless loads equitably over the generators, makes sure that the generator works normally and the electricity power system functions savely. This dissertation designs the field regulator for hydraulic generator, including hardware design and software design. The following paragraph is devoted to introducing the content of the design.This design of the field regulator includes the major loop circuitry and the control scheme of the excitation control system, sets automatic adjustment ways channel: adjustment of steady terminal voltage, adjustment of steady exciting current, adjustment of steady reactive power and steady power factors, to achieve excitation control for synchronous generator under all kinds of operating conditions and run modes. And this design has set a manual channel independent of PLC control way as a backup. The design should allow online-nondisturbance-switch among the control ways, and allow host microcomputers'long distance control and monitoring on excitation installment through communication interface.The excitation installment uses three-phase all-control-brige rectification self-separative excitationsystem. When shutdown normally, the system uses contravariant demagnetization. While emergency shutdown, the system achieves demagnetization with field circuit breaker and linear resistance. The system can start excitation with residual voltage, or with separative excitation from external power source. The concrete circuit includes: Signal transformation unit, manual-automatic phase shifting triggering circuit, manual regulation unit.The circuit designed enables self-regulation of the output voltage of the hydraulic generator, keep the output voltage nearly steady. It has met the design specification.