A method of controlling an induction generator such as an automotive starter-alternator or a windmill is disclosed. The method comprises using a minimal number of current sensors and controlling at least one of a machine flux, an output voltage and generator torque, based on the stator or rotor flux magnitude and position. This method comprises measuring a plurality of current amounts; transforming them into a two phase reference system; measuring a DC voltage; measuring voltage amounts in the generator; transforming the plurality of voltage amounts into the two phase reference system; calculating a flux in the generator; comparing the calculated flux magnitude with a desired flux; determining a d-axis voltage; determining a desired torque amount; comparing the desired torque amount with an estimated torque amount; determining a q-axis voltage; and transforming the d-axis voltage and the q-axis voltage to stationary reference frame n-phase voltages using the position of the flux.
A system for generating updated reactive capability curves of a generator operates the genarator at a number of operating load levels and at a number of different power factors to collect data regarding the real and reactive power generated at each of the various operating load levels and power factors. Subsequently, the system analyzes the collected data to determine an actual reactive capability curve of the generator. The system also provides generator health monitoring and identifies changes and trends in the capability curves of the generator. The updated reactive capability curves may be used by an economic dispatch program in determining optimum MW and MVAR setpoints for the generator.
