针对无刷双馈风力发电系统,稳态时,采用基于空间矢量调制(Space Vector Modulation,SVM)的直接功率控制(Direct Power Control,DPC)技术。在电网电压对称跌落条件下,理论分析功率绕组磁链与控制绕组电压的关系,对于故障期间控制绕组会...针对无刷双馈风力发电系统,稳态时,采用基于空间矢量调制(Space Vector Modulation,SVM)的直接功率控制(Direct Power Control,DPC)技术。在电网电压对称跌落条件下,理论分析功率绕组磁链与控制绕组电压的关系,对于故障期间控制绕组会产生较大的过电流,严重时可能损害变流器功率器件的问题,在原有的控制方案中引入前馈控制。通过将可观测的功率绕组电流进行微分运算后得到反映控制绕组反电势的直接干扰量,将其经前馈控制器引入到控制电压的参考值端,形成一种基于前馈控制的SVM-DPC复合控制。仿真结果表明,基于功率绕组电流微分前馈控制的复合控制策略可以在一定程度上抑制控制绕组过电流,能为无刷双馈风力发电机实现低电压穿越提供参考。展开更多
This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC). With right-angle triangle relation ...This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC). With right-angle triangle relation of phasors and principle of conservation of energy, a phasor adjustment method and the relevant low-frequency mathematical model of the system are analyzed in detail, both in rectification and regeneration modes for the converter, are discussed. For improving the traditional PAC dynamic performance, variable load current is detected indirectly by the change of the DC voltage, which is fed to the control system as an additional control variable to generate modulation index and phase angle. Also, the algorithm is derived and the system principle is introduced. Experimental results from a 3 kw laboratory device are included to demonstrate the effectiveness of the proposed control strategy.展开更多
针对双馈风力发电机网侧变换器因负载变化和滤波参数摄动导致控制效果不佳的问题,文中提出一种扩张状态观测器(extended state observer,ESO)与滑模控制相结合的网侧变换器双闭环控制策略,内环采用以功率为状态变量的基于ESO的滑模直接...针对双馈风力发电机网侧变换器因负载变化和滤波参数摄动导致控制效果不佳的问题,文中提出一种扩张状态观测器(extended state observer,ESO)与滑模控制相结合的网侧变换器双闭环控制策略,内环采用以功率为状态变量的基于ESO的滑模直接功率控制,外环采用以电压平方为状态变量的基于ESO的滑模控制。首先,应用ESO对系统状态变量与包含系统未建模动态、负载变化和滤波参数摄动等不确定项进行估计,无需系统的精确数学模型即可设计滑模控制方法,实现网侧变换器在复杂环境下的鲁棒控制。此外,引入功率差前馈环节,可减小负载变化时外环滑模控制非线性带来的冲击。最后,对负载变化和滤波参数摄动2个算例进行仿真。结果表明,与传统矢量控制和滑模控制相比,所提控制策略在复杂环境下具有更强的鲁棒性。展开更多
文摘针对无刷双馈风力发电系统,稳态时,采用基于空间矢量调制(Space Vector Modulation,SVM)的直接功率控制(Direct Power Control,DPC)技术。在电网电压对称跌落条件下,理论分析功率绕组磁链与控制绕组电压的关系,对于故障期间控制绕组会产生较大的过电流,严重时可能损害变流器功率器件的问题,在原有的控制方案中引入前馈控制。通过将可观测的功率绕组电流进行微分运算后得到反映控制绕组反电势的直接干扰量,将其经前馈控制器引入到控制电压的参考值端,形成一种基于前馈控制的SVM-DPC复合控制。仿真结果表明,基于功率绕组电流微分前馈控制的复合控制策略可以在一定程度上抑制控制绕组过电流,能为无刷双馈风力发电机实现低电压穿越提供参考。
文摘This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC). With right-angle triangle relation of phasors and principle of conservation of energy, a phasor adjustment method and the relevant low-frequency mathematical model of the system are analyzed in detail, both in rectification and regeneration modes for the converter, are discussed. For improving the traditional PAC dynamic performance, variable load current is detected indirectly by the change of the DC voltage, which is fed to the control system as an additional control variable to generate modulation index and phase angle. Also, the algorithm is derived and the system principle is introduced. Experimental results from a 3 kw laboratory device are included to demonstrate the effectiveness of the proposed control strategy.
文摘针对双馈风力发电机网侧变换器因负载变化和滤波参数摄动导致控制效果不佳的问题,文中提出一种扩张状态观测器(extended state observer,ESO)与滑模控制相结合的网侧变换器双闭环控制策略,内环采用以功率为状态变量的基于ESO的滑模直接功率控制,外环采用以电压平方为状态变量的基于ESO的滑模控制。首先,应用ESO对系统状态变量与包含系统未建模动态、负载变化和滤波参数摄动等不确定项进行估计,无需系统的精确数学模型即可设计滑模控制方法,实现网侧变换器在复杂环境下的鲁棒控制。此外,引入功率差前馈环节,可减小负载变化时外环滑模控制非线性带来的冲击。最后,对负载变化和滤波参数摄动2个算例进行仿真。结果表明,与传统矢量控制和滑模控制相比,所提控制策略在复杂环境下具有更强的鲁棒性。
