| 摘要 |
An electric power generator system is provided with improved power efficienc y due to a reduced sensitivity to errors in the sensing of angular rotor position. Th e system includes a power generator with a rotor, and a position encoder connected to sense angular position of the rotor and to generate a position signal accordingly. A processor receives the position signal, calculates an angular position in response, calculates an estimated angular position based on earlier received position signals, and finally generates a processed angular position based on the calculated angular position and the estimated angular position. This processed angular position is a more reliable measure of the rotor position since it is based on earlier position inputs, preferably several earlier inputs. This provides a high immunity to short te rm errors in the position signal, and for e.g. wind turbines this means that normal operation can be maintained in situations where the position encoder temporarily fails , and in case of complete failure, operation can be maintained long enough to avoid emergency shut down. In preferred embodiments, the processor is arranged to prefilter the position signal, i.e. detect and correct prior to calculating the angula r position. It preferably also includes an error handling based on comparing t he estimated angular position with the calculated angular position and thereby determines an input to a Phase Locked Loop based estimator that is also used to provide the processed angular position. |
