A blend braking system of heavy vehicle was proposed.The main control part of the system is the electro hydraulic proportional servo valve.A nonlinear model of brake cylinder controlled by the valve was deduced throug...A blend braking system of heavy vehicle was proposed.The main control part of the system is the electro hydraulic proportional servo valve.A nonlinear model of brake cylinder controlled by the valve was deduced through the analysis of its control property and system feature.The transfer function of the system was also proposed,and the hydraulic inherent frequency and the PID closed-loop system feature were calculated.The simulated result is consistent with those tested in the bench and on the site with 50 t heavy vehicle.The experimental result shows that the control method has quick response and high precision.展开更多
抽水蓄能具有突出的能量密度和功率密度优势。借助其快速响应和灵活调节能力,能够有效平抑新能源出力随机波动,提高系统频率稳定性。针对抽水蓄能如何融入电力系统频率稳定控制问题,提出一种基于转速保护的变速抽蓄自适应综合惯量控制策...抽水蓄能具有突出的能量密度和功率密度优势。借助其快速响应和灵活调节能力,能够有效平抑新能源出力随机波动,提高系统频率稳定性。针对抽水蓄能如何融入电力系统频率稳定控制问题,提出一种基于转速保护的变速抽蓄自适应综合惯量控制策略,并采用优化思想对控制参数进行求解。在考虑短期频率变化率(rate of change of frequency,RoCoF)预测及变速抽蓄自适应综合惯量控制响应系统频率变化的基础上,对传统电力系统低频切泵策略进行改进,提出定速抽蓄自适应低频切泵控制策略。通过不同场景下的仿真验证,结果表明,将变速抽蓄自适应综合惯量调频控制策略与改进低频切泵策略相结合能够更好地适应高比例新能源电力系统,提升系统的频率调节性能。展开更多
针对过程复杂且结构未知的对象,在保证模型有效性的前提下,根据数据信息构建简单模型来简化控制器的求解是亟待解决的问题。以受控自回归模型为例,提出一种基于修正最小角回归算法的稀疏辨识方法。首先将系统模型转化为过参数化的高维...针对过程复杂且结构未知的对象,在保证模型有效性的前提下,根据数据信息构建简单模型来简化控制器的求解是亟待解决的问题。以受控自回归模型为例,提出一种基于修正最小角回归算法的稀疏辨识方法。首先将系统模型转化为过参数化的高维稀疏模型,然后将最小角回归算法用于稀疏系统辨识,并提出绝对角度停止准则,使算法经过少量的迭代即可获得模型的稀疏参数估计,并同时获得有效的时滞和阶次估计。结合辨识得到的受控自回归模型,引入一种基于指定相位点频率和增益的比例-积分-微分(proportional integral derivative,PID)控制器。数值仿真和平衡机器人的姿态控制仿真表明,该稀疏辨识算法在低数据量下具有较高的辨识精度,建立的模型具有较好的泛化性能,控制器具有良好的控制效果。展开更多
文摘A blend braking system of heavy vehicle was proposed.The main control part of the system is the electro hydraulic proportional servo valve.A nonlinear model of brake cylinder controlled by the valve was deduced through the analysis of its control property and system feature.The transfer function of the system was also proposed,and the hydraulic inherent frequency and the PID closed-loop system feature were calculated.The simulated result is consistent with those tested in the bench and on the site with 50 t heavy vehicle.The experimental result shows that the control method has quick response and high precision.
文摘抽水蓄能具有突出的能量密度和功率密度优势。借助其快速响应和灵活调节能力,能够有效平抑新能源出力随机波动,提高系统频率稳定性。针对抽水蓄能如何融入电力系统频率稳定控制问题,提出一种基于转速保护的变速抽蓄自适应综合惯量控制策略,并采用优化思想对控制参数进行求解。在考虑短期频率变化率(rate of change of frequency,RoCoF)预测及变速抽蓄自适应综合惯量控制响应系统频率变化的基础上,对传统电力系统低频切泵策略进行改进,提出定速抽蓄自适应低频切泵控制策略。通过不同场景下的仿真验证,结果表明,将变速抽蓄自适应综合惯量调频控制策略与改进低频切泵策略相结合能够更好地适应高比例新能源电力系统,提升系统的频率调节性能。
文摘针对过程复杂且结构未知的对象,在保证模型有效性的前提下,根据数据信息构建简单模型来简化控制器的求解是亟待解决的问题。以受控自回归模型为例,提出一种基于修正最小角回归算法的稀疏辨识方法。首先将系统模型转化为过参数化的高维稀疏模型,然后将最小角回归算法用于稀疏系统辨识,并提出绝对角度停止准则,使算法经过少量的迭代即可获得模型的稀疏参数估计,并同时获得有效的时滞和阶次估计。结合辨识得到的受控自回归模型,引入一种基于指定相位点频率和增益的比例-积分-微分(proportional integral derivative,PID)控制器。数值仿真和平衡机器人的姿态控制仿真表明,该稀疏辨识算法在低数据量下具有较高的辨识精度,建立的模型具有较好的泛化性能,控制器具有良好的控制效果。
