外文中英文翻译电力系统中的励磁系统.doc

Power system of excitation system In the power system, the big unit is usually much return high-voltage transmission through to the distance, to reduce power load center, usually by without loss of wattless situ balance. But this way is easy to destruction, causing voltage instability. Excitation control system is an important part of synchronous generator power system, to ensure normal operation conditions voltage electricity conveying rate between basically unchanged, ensure its reactive load distribution, improve the power system static stability, and because has forced excitation device, in power system is at fault, can quickly will generator excitation current increasing rapidly, so as to ensure protection device and reliable sensitive, improve the power system dynamic stability. A, excitation control principle Synchronous generator excitation system is by exciter, generators, voltage regulator components, in this system, excitation controller detection generator voltage of UF and machine with UF reference voltage compared to UC voltage difference (UC - UF), through comprehensive amplification UK, obtaining control voltage UK = K (UC - UF). By this type, it is easy to see when the generator voltage of UF rise, machine will reduce the voltage difference, so that, through comprehensive amplification the control voltage UK also can be reduced, so, exciter excitation current and voltage of generator rotor will fall subsequently, such, generator machine with the decrease of voltage of UF also, so that the voltage across the machine generator disturbance was offset rising. Therefore, excitation system is raising power system stability operation, maintain and improve the synchronous motor voltage level power limits and power system transmission power, and other functions. In addition, in this system can also according to the actual need additional damping, fuzzy neural auxiliary control function. The main part of the excitation control, its effect is excitation adju