Conclusions
An anomaly identification model for wind turbine state parameters was presented in this paper. The conclusion can be summarized as follows: Firstly, the wind turbine state parameter prediction model has been developed and trained by the GABP algorithm. The influence of the training algorithm, data samples and input parameters on the prediction performance of the developed models has been analyzed. 1) The GABP optimized model can provide much higher accuracy than the BPNN based model: the MSE(°C), MAE(°C), and MAPE(%) of GABP and BP with 1 minute interval time are (0.0530, 0.0367, 0.0964) and (0.0705, 0.0556, 0.1476), respectively; the MSE(°C), MAE(°C), and MAPE(%) of GABP and BP with 10 minute interval time are (0.1998, 0.1625, 0.4380) and (0.2884, 0.2255, 0.6247), respectively; the MSE(°C), MAE(°C), and MAPE(%) of GABP and BP with 15 minute interval time are (0.2701, 0.2096, 0.5435) and (0.3095, 0.2385, 0.5977), respectively. 2) The accuracy of prediction models developed by using the proposed data sampling method is higher than that trained by the current data: the MSE(°C), MAE(°C), and MAPE(%) of recent samples and samples of this paper with 1 minute interval time are (1.3822, 1.0563, 2.0231) and (1.0977, 0.6448, 1.4491), respectively; the MSE(°C), MAE(°C), and MAPE(%) of recent samples and samples of this paper with 10 minute interval time are (1.5479, 0.9888, 2.1844) and (1.2514, 0.9661, 1.8789), respectively; the MSE(°C), MAE(°C), and MAPE(%) of recent samples and samples of this paper with 15 minute interval time are (1.7643, 1.2633, 2.3431) and (1.4327, 1.1608, 2.0742), respectively. 3) Selecting the state parameters with wind speed and the parameters with large correlation as input parameters can further improve the prediction accuracy: the MSE(°C), MAE(°C), and MAPE(%) of Input parameters including a) Wind speeds and the previous monitored values, b) Ambient temperatures and the previous monitored values, c) Wind speeds, ambient temperatures and the previous monitored values, d) Wind speeds, temperature of gearbox input bearing and the previous monitored values are (1.4473, 1.0901, 2.1886), (1.2327, 0.9505, 2.0491), (1.1356, 0.8087, 1.5926), and (1.1180, 0.7692, 1.3826), respectively.