在设计和研发大功率宽输出电压范围的双有源桥(dual active bridge,DAB)变换器时,传统的电流应力优化策略往往只关注移相比优化,忽略了电感量变化对电流应力的影响,这可能导致在大功率应用中电流应力超出理论预期,从而降低开关管的可靠...在设计和研发大功率宽输出电压范围的双有源桥(dual active bridge,DAB)变换器时,传统的电流应力优化策略往往只关注移相比优化,忽略了电感量变化对电流应力的影响,这可能导致在大功率应用中电流应力超出理论预期,从而降低开关管的可靠性。因此,在大功率应用场景下,为使变换器在全功率范围内获得最小电流应力,首先提出了考虑电感量随电流应力变化的动态关系,并基于此关系选择在恰当电感量下的优化三移相控制方法;其次,通过分析三移相控制并建立相应的数学模型,利用KKT(Karush-Kuhn-Tucker)条件寻求最优移相比组合,以实现电流应力优化;最后,搭建额定功率为100 kW的DAB变换器仿真模型及样机实验平台进行验证。实验结果表明,与传统三移相控制方法相比,所提方法在仿真和实验中都表现出较高的有效性,确保了变换器在整个运行过程中电流应力始终保持在理论预期范围内,保证了变换器在稳定运行时开关管的可靠性。展开更多
Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given qua...Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given quadratic performance criteria. First, a control law is established for jump systems based on pontryagin’s minimum principle and it can be constructed through numerical solution of iterative equations. The aim of this control strategy is to obtain an optimal control which can minimize the cost function under the worst disturbance at every sampling time. Due to the difficulty of the assurance of stability, then the above mentioned approach is improved by determining terminal weighting matrix which satisfies cost monotonicity condition. The control move which is calculated by using this type of terminal weighting matrix as boundary condition naturally guarantees the mean square stability of the closed-loop system. A sufficient condition for the existence of the terminal weighting matrix is presented in linear matrix inequality （LMI） form which can be solved efficiently by available software toolbox. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method.展开更多
为改善六相永磁同步电机一相开路故障后的性能,建立了适用于容错控制的静止坐标变换阵,并建立了考虑3次谐波影响的旋转坐标系下的电压和转矩方程。针对一次旋转坐标变换不能对电压模型完全解耦的情况,提出对d-q子空间应用二次旋转坐标...为改善六相永磁同步电机一相开路故障后的性能,建立了适用于容错控制的静止坐标变换阵,并建立了考虑3次谐波影响的旋转坐标系下的电压和转矩方程。针对一次旋转坐标变换不能对电压模型完全解耦的情况,提出对d-q子空间应用二次旋转坐标变换得到完全解耦的d-q轴电压分量。提出了基于磁势不变原则的定子电流幅值最小(stator current magnitude minimum,SCMM)闭环控制策略,为抑制3次谐波磁链和3次谐波电感作用,推导了d-q轴三次谐波电压的补偿量。仿真和实验验证了提出的补偿控制策略对三次谐波影响消除的有效性,明显改善了定子电流幅值最小控制策略下单相开路后的性能。展开更多
文摘在设计和研发大功率宽输出电压范围的双有源桥(dual active bridge,DAB)变换器时,传统的电流应力优化策略往往只关注移相比优化,忽略了电感量变化对电流应力的影响,这可能导致在大功率应用中电流应力超出理论预期,从而降低开关管的可靠性。因此,在大功率应用场景下,为使变换器在全功率范围内获得最小电流应力,首先提出了考虑电感量随电流应力变化的动态关系,并基于此关系选择在恰当电感量下的优化三移相控制方法;其次,通过分析三移相控制并建立相应的数学模型,利用KKT(Karush-Kuhn-Tucker)条件寻求最优移相比组合,以实现电流应力优化;最后,搭建额定功率为100 kW的DAB变换器仿真模型及样机实验平台进行验证。实验结果表明,与传统三移相控制方法相比,所提方法在仿真和实验中都表现出较高的有效性,确保了变换器在整个运行过程中电流应力始终保持在理论预期范围内,保证了变换器在稳定运行时开关管的可靠性。
基金supported by the National Natural Science Foundation of China (60974001)Jiangsu "Six Personnel Peak" Talent-Funded Projects
文摘Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given quadratic performance criteria. First, a control law is established for jump systems based on pontryagin’s minimum principle and it can be constructed through numerical solution of iterative equations. The aim of this control strategy is to obtain an optimal control which can minimize the cost function under the worst disturbance at every sampling time. Due to the difficulty of the assurance of stability, then the above mentioned approach is improved by determining terminal weighting matrix which satisfies cost monotonicity condition. The control move which is calculated by using this type of terminal weighting matrix as boundary condition naturally guarantees the mean square stability of the closed-loop system. A sufficient condition for the existence of the terminal weighting matrix is presented in linear matrix inequality （LMI） form which can be solved efficiently by available software toolbox. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method.
文摘为改善六相永磁同步电机一相开路故障后的性能,建立了适用于容错控制的静止坐标变换阵,并建立了考虑3次谐波影响的旋转坐标系下的电压和转矩方程。针对一次旋转坐标变换不能对电压模型完全解耦的情况,提出对d-q子空间应用二次旋转坐标变换得到完全解耦的d-q轴电压分量。提出了基于磁势不变原则的定子电流幅值最小(stator current magnitude minimum,SCMM)闭环控制策略,为抑制3次谐波磁链和3次谐波电感作用,推导了d-q轴三次谐波电压的补偿量。仿真和实验验证了提出的补偿控制策略对三次谐波影响消除的有效性,明显改善了定子电流幅值最小控制策略下单相开路后的性能。
