为充分发挥各类分布式资源的特点和配电网的可调节能力,以提供性能更优的动态辅助服务,文中提出一种面向配电网格虚拟电厂(meshed distribution virtual power plant,MVPP)的动态频率聚合控制方法。首先,明确MVPP的整体架构,建立针对一...为充分发挥各类分布式资源的特点和配电网的可调节能力,以提供性能更优的动态辅助服务,文中提出一种面向配电网格虚拟电厂(meshed distribution virtual power plant,MVPP)的动态频率聚合控制方法。首先,明确MVPP的整体架构,建立针对一次调频场景、能够聚合其内部各类分布式资源动态特性的频率控制模型。然后,采用基于自适应动态频率匹配的控制方法解决动态频率聚合模型控制设计问题,通过在线自适应方法分解期望特性,并利用H∞最优鲁棒控制方法为各设备设计本地反馈控制器,精确动态匹配分解一次调频的期望特性。仿真结果验证了所提控制方法的有效性,该方法能在负载扰动、新能源出力波动等场景下,通过各资源互补显著改善系统一次调频特性。所提策略可为空间分布的聚合单元参与动态调频辅助服务提供新的解决思路。展开更多
This paper proposes an active fault-tolerant control strategy for an aircraft with dissimilar redundant actuation system （DRAS） that has suffered from vertical tail damage. A damage degree coefficient based on the e...This paper proposes an active fault-tolerant control strategy for an aircraft with dissimilar redundant actuation system （DRAS） that has suffered from vertical tail damage. A damage degree coefficient based on the effective vertical tail area is introduced to parameterize the damaged flight dynamic model. The nonlinear relationship between the damage degree coefficient and the corresponding stability derivatives is considered. Furthermore, the performance degradation of new input channel with electro-hydrostatic actuator （EHA） is also taken into account in the damaged flight dynamic model. Based on the accurate damaged flight dynamic model, a composite method of linear quadratic regulator （LQR） integrating model reference adaptive control （MRAC） is proposed to reconfigure the fault-tolerant control law. The numerical simulation results validate the effectiveness of the proposed fault-tolerant control strategy with accurate flight dynamic model. The results also indicate that aircraft with DRAS has better fault-tolerant control ability than the traditional ones when the vertical tail suffers from serious damage.展开更多
An improved Narendra model reference adaptive control (MRAC) scheme isproposed to research one variable displacement pump driving four hydraulic variable displacementmotors. This approach not only ensures the underdam...An improved Narendra model reference adaptive control (MRAC) scheme isproposed to research one variable displacement pump driving four hydraulic variable displacementmotors. This approach not only ensures the underdamped and unstable system be global uniformasymptotic stability, but also has good robustness in these aspects of modeling uncertainty,pressure fluctuation of constant pressure network, and disturbance from external load, which alsoupgrades the rapidity of system response so as to make controlled system with nicer dynamic quality.The scheme of one pump driving four motors can meet the demand on off-road mobility of engineeringvehicles and armored cars. A proof of stability about improved Narendra MRAC scheme is also given.展开更多
文摘为充分发挥各类分布式资源的特点和配电网的可调节能力,以提供性能更优的动态辅助服务,文中提出一种面向配电网格虚拟电厂(meshed distribution virtual power plant,MVPP)的动态频率聚合控制方法。首先,明确MVPP的整体架构,建立针对一次调频场景、能够聚合其内部各类分布式资源动态特性的频率控制模型。然后,采用基于自适应动态频率匹配的控制方法解决动态频率聚合模型控制设计问题,通过在线自适应方法分解期望特性,并利用H∞最优鲁棒控制方法为各设备设计本地反馈控制器,精确动态匹配分解一次调频的期望特性。仿真结果验证了所提控制方法的有效性,该方法能在负载扰动、新能源出力波动等场景下,通过各资源互补显著改善系统一次调频特性。所提策略可为空间分布的聚合单元参与动态调频辅助服务提供新的解决思路。
基金supported by the National Basic Research Program of China (No 2014CB046402)the National Natural Science Foundation of China (No.51575019)111 Project of China
文摘This paper proposes an active fault-tolerant control strategy for an aircraft with dissimilar redundant actuation system （DRAS） that has suffered from vertical tail damage. A damage degree coefficient based on the effective vertical tail area is introduced to parameterize the damaged flight dynamic model. The nonlinear relationship between the damage degree coefficient and the corresponding stability derivatives is considered. Furthermore, the performance degradation of new input channel with electro-hydrostatic actuator （EHA） is also taken into account in the damaged flight dynamic model. Based on the accurate damaged flight dynamic model, a composite method of linear quadratic regulator （LQR） integrating model reference adaptive control （MRAC） is proposed to reconfigure the fault-tolerant control law. The numerical simulation results validate the effectiveness of the proposed fault-tolerant control strategy with accurate flight dynamic model. The results also indicate that aircraft with DRAS has better fault-tolerant control ability than the traditional ones when the vertical tail suffers from serious damage.
文摘An improved Narendra model reference adaptive control (MRAC) scheme isproposed to research one variable displacement pump driving four hydraulic variable displacementmotors. This approach not only ensures the underdamped and unstable system be global uniformasymptotic stability, but also has good robustness in these aspects of modeling uncertainty,pressure fluctuation of constant pressure network, and disturbance from external load, which alsoupgrades the rapidity of system response so as to make controlled system with nicer dynamic quality.The scheme of one pump driving four motors can meet the demand on off-road mobility of engineeringvehicles and armored cars. A proof of stability about improved Narendra MRAC scheme is also given.
