Brushless Exciter Modeling for Small Salient Pole Alternators Using Finite Elements

The self and mutual inductances of an exciter for a genset altemator are estimated for different rotor angular positions by the use of finite element (FE) techniques. These inductances, which are described by complex functions, are measured using a stationary test and compared with calculated values. A real-time computer model for the exciter, the load, and the diode bridge mounted on the rotor is proposed, and a sample of performance prediction and measurement for a specific transient condition of the exciter is presented as confirmation of the method. The model thus validated is ultimately to be included in the evolving total system model used for simulation of genset transient and steady-state performance.