针对带有未知参数和有界干扰的风电机组最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制问题,从风电机组的运动学和动力学模型出发,在最佳转矩控制方法的基础上提出一种自适应反演滑模控制策略。在满足最大功率跟踪控制要求的...针对带有未知参数和有界干扰的风电机组最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制问题,从风电机组的运动学和动力学模型出发,在最佳转矩控制方法的基础上提出一种自适应反演滑模控制策略。在满足最大功率跟踪控制要求的条件下,设计自适应控制律提高系统的鲁棒性,采用反演的方法来提高系统的全局渐进稳定性,使系统在参数摄动及外部扰动存在的情况下跟踪误差快速收敛。为进一步改善系统的控制性能,采用粒子群优化算法对正定矩阵Q的参数进行优化。将提出的控制策略与常规滑模控制和传统最佳转矩控制进行对比分析,证明了控制策略的可行性、有效性。展开更多
The thermal infrared channel (IRS4) of HJ-1B satellite obtains view zenith angles (VZA) up to ±33°. The view angle should be taken into account when retrieving land surface temperature (LST) from IRS4 data. ...The thermal infrared channel (IRS4) of HJ-1B satellite obtains view zenith angles (VZA) up to ±33°. The view angle should be taken into account when retrieving land surface temperature (LST) from IRS4 data. This study aims at improving the mono-window algorithm for retrieving LST from IRS4 data. Based on atmospheric radiative transfer simulations,a model for correcting the VZA effects on atmospheric transmittance is proposed. In addition,a generalized model for calculating the effective mean atmospheric temperature is developed. Validation with the simulated dataset based on standard atmospheric profiles reveals that the improved mono-window algorithm for IRS4 obtains high accuracy for LST retrieval,with the mean absolute error (MAE) and root mean square error (RMSE) being 1.0 K and 1.1 K,respectively. Numerical experiment with the radiosonde profile acquired in Beijing in winter demonstrates that the improved mono-window algorithm exhibits excellent ability for LST retrieval,with MAE and RMSE being 0.6 K and 0.6 K,respectively. Further application in Qinghai Lake and comparison with the Moderate-Resolution Imaging Spectroradiometer (MODIS) LST product suggest that the improved mono-window algorithm is applicable and feasible in actual conditions.展开更多
文摘针对带有未知参数和有界干扰的风电机组最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制问题,从风电机组的运动学和动力学模型出发,在最佳转矩控制方法的基础上提出一种自适应反演滑模控制策略。在满足最大功率跟踪控制要求的条件下,设计自适应控制律提高系统的鲁棒性,采用反演的方法来提高系统的全局渐进稳定性,使系统在参数摄动及外部扰动存在的情况下跟踪误差快速收敛。为进一步改善系统的控制性能,采用粒子群优化算法对正定矩阵Q的参数进行优化。将提出的控制策略与常规滑模控制和传统最佳转矩控制进行对比分析,证明了控制策略的可行性、有效性。
基金Under the auspices of Opening Funding of State Key Laboratory for Remote Sensing ScienceNational High-tech Research and Development Program (863 Program) (No. 2007AA120205, 2007AA120306)
文摘The thermal infrared channel (IRS4) of HJ-1B satellite obtains view zenith angles (VZA) up to ±33°. The view angle should be taken into account when retrieving land surface temperature (LST) from IRS4 data. This study aims at improving the mono-window algorithm for retrieving LST from IRS4 data. Based on atmospheric radiative transfer simulations,a model for correcting the VZA effects on atmospheric transmittance is proposed. In addition,a generalized model for calculating the effective mean atmospheric temperature is developed. Validation with the simulated dataset based on standard atmospheric profiles reveals that the improved mono-window algorithm for IRS4 obtains high accuracy for LST retrieval,with the mean absolute error (MAE) and root mean square error (RMSE) being 1.0 K and 1.1 K,respectively. Numerical experiment with the radiosonde profile acquired in Beijing in winter demonstrates that the improved mono-window algorithm exhibits excellent ability for LST retrieval,with MAE and RMSE being 0.6 K and 0.6 K,respectively. Further application in Qinghai Lake and comparison with the Moderate-Resolution Imaging Spectroradiometer (MODIS) LST product suggest that the improved mono-window algorithm is applicable and feasible in actual conditions.
