Basic structure and working principle of reactive-reactor composite phase-complex three-phase alternator

Basic structure

The generator is equipped with a reactive reactance combined composite phase compound excitation device based on the basic structure of the brushed three-phase alternator shown in Figure 3-4, and its external shape is shown in Figure 3-19, which includes the reactance converter. , three-phase rectifier bridge and magnetic field varistor. As a controllable phase compound excitation device, it is also necessary to install a shunt automatic voltage regulator (STL) low-power generator without a shunt automatic voltage regulator, and the voltage performance can meet the requirements of use.

2. Working principle

Figure 3-20 shows the principle circuit of the reactive-reactor composite phase-complex three-phase alternator. When the generator is driven by the internal combustion engine to the no-load speed near the rated value, the residual magnetic field of the rotor core is used, and the induced voltage of the generator stator secondary winding is phase-shifted by the secondary winding of the reactance converter to provide a generator no-load voltage. The voltage component Ifu of the AC excitation current is rectified by the three-phase rectifier bridge group to provide no-load excitation current to the generator rotor winding. The stator main winding outputs a three-phase voltage after serially connecting the reactance converter to the secondary winding. When the load is put on the generator, the power converter anti-multiplexed excitation effect, a current component in the secondary winding and the load current induces a corresponding AC generator excitation current Ifi, therefore, the load and Ifi two Ifu The excitation current components are geometrically superimposed and subjected to three-phase rectification to provide a load excitation current to the rotor windings, thereby maintaining a constant generator terminal voltage. The steady-state voltage regulation rate of the uncontrollable composite phase compound excitation generator is generally not more than ± 5%.

In order to further improve the voltage regulation accuracy, a shunt automatic voltage regulator can be added. STL type shunt automatic voltage regulator specially designed for phase compound excitation generator , there are 6 terminal blocks, wherein the two contacts of the mark "AC400" are respectively connected to the generator terminal U, W phase, F1 contact and three-phase rectifier bridge group. The "+" terminal is connected, the F2 contact is connected to the U-phase terminal of the AC side of the three-phase rectifier bridge group, and the R1 and R2 contacts are connected to the potentiometer.