Excitation system for synchronous generator is one of the core equipment, with the development of modern control theory and computer technology, the excitation system of voltage regulation also from mechanical type transformation for electronics, electromagnetic type. At home and abroad of the mainstream of large generator excitation mode there are two main types: since the shunt static excitation and compressors brushless excitation. This article introduced the brief and clear manner & other; Brushless excitation & throughout; 。 in 1000 mw generating sets compressors brushless excitation system as an example. The excitation system as shown in the figure below:
the excitation system is mainly composed of vice exciter, main exciter, rotating rectifier device and AVR -PU of excitation regulator. Deputy exciter of three phase current,400Hz）After the power unit rectifier supply main exciter excitation winding (The stator), the main excitation and pivot (Rotor)Three phase current of the output,150Hz）Directly into the rotating rectifier device, rotating rectifier device of dc output field winding in the rotor of the generator, thus constituted of generator excitation power supply. vice exciter with permanent magnet, intermediate frequency generator has good external characteristic, from the generator no-load to forced excitation, the terminal voltage change rate is less than 10%, and the configuration used to monitor voltage transducer. Pair of exciter rack is equipped with belt disc of the three-phase winding core and the rotor is composed of wheel hub with hanging pole function, 16 poles, each pole is composed of ten independent permanent magnet, the magnet is placed in a nonmagnetic metal shell, and bolt is fixed on the wheel. Deputy exciter three-phase output by the excitation regulator cabinet directly into the power unit. main exciter is a small three phase pole synchronous generator, a rotating armature device level 6. Six pole installed within the stator frame, bus mounted on the pole shoe, its damping winding is formed after connection. The rotor is composed of multilayer laminated, laminated by through bolt on the compression ring suppression. Three-phase winding is inserted into the rotor slot, within the scope of the core length to carry on the cross, and then the end of the rotor winding with glass fiber line turns to be fixed, and rectifying plate connection. rotating rectifier in two rectifying ring, its main components are installed on the silicon diode rectifier ring, each a set of two diodes installed in aluminum alloy heat dissipation, and thus they can be connected in parallel, at the same time and in series with the fuse. In order to suppress overvoltage, because of the rectifier rectifier loop to install 6 each composed of a capacitor and resistor resistance capacity to absorb circuit. While dc current from rectifying ring through radial bolt into the dc lead arrangement in the center of the shaft hole.
