Active front steering(AFS)system has been used as a promising technology which improves the steering portability and handing stability of vehicles.It employs a steering motor to realize the functions of variable steer...Active front steering(AFS)system has been used as a promising technology which improves the steering portability and handing stability of vehicles.It employs a steering motor to realize the functions of variable steering ratio and vehicle stability control.However,it has a serious problem of unexpected reaction hand wheel torque caused by the additional steering angle.In this paper,the optimum hand wheel torque is designed based on the linear tire model.Considering the uncertainty and disturbance of the steering system and vehicle,an H∞controller is developed to make sure the hand wheel torque follows the reference torque accurately and quickly.The simulation shows that the proposed controller can compensate the unnatural reaction torque and provide a good steering feel for the driver.展开更多
Photovoltaic(PV)inverter-based volt/var control(VVC)is highly promising to tackle the emerging voltage regulation challenges brought by increasing PV penetration.However,PV inverter operational reliability has arisen ...Photovoltaic(PV)inverter-based volt/var control(VVC)is highly promising to tackle the emerging voltage regulation challenges brought by increasing PV penetration.However,PV inverter operational reliability has arisen as a critical concern for practical VVC implementation.This paper proposes a new PV inverter based VVC optimization model and a Pareto front analysis method for maintaining a satisfactory inverter lifetime.First,reliability of the vulnerable DC-link capacitor inside a PV inverter is analyzed,and long-term VVC impact on inverter operational reliability is identified.Second,a multi-objective PV inverter based VVC optimization model is proposed for minimizing both inverter apparent power output and network power loss with a weighting factor.Third,a Pareto front analysis method is developed to visualize the impact of the weighting factor on VVC performance and inverter reliability,thus determining the effective weighting factor to reduce network power loss with expected inverter lifetime.Effectiveness of the proposed VVC optimization model and Pareto front analysis method are verified in a case study.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51375007 and 51205191)NUAA Research Funding(Grant No.NS2013015)
文摘Active front steering(AFS)system has been used as a promising technology which improves the steering portability and handing stability of vehicles.It employs a steering motor to realize the functions of variable steering ratio and vehicle stability control.However,it has a serious problem of unexpected reaction hand wheel torque caused by the additional steering angle.In this paper,the optimum hand wheel torque is designed based on the linear tire model.Considering the uncertainty and disturbance of the steering system and vehicle,an H∞controller is developed to make sure the hand wheel torque follows the reference torque accurately and quickly.The simulation shows that the proposed controller can compensate the unnatural reaction torque and provide a good steering feel for the driver.
基金This work was supported in part by NTU Grant No.021542-00001in part by Australian Government Research Training Program Scholarship。
文摘Photovoltaic(PV)inverter-based volt/var control(VVC)is highly promising to tackle the emerging voltage regulation challenges brought by increasing PV penetration.However,PV inverter operational reliability has arisen as a critical concern for practical VVC implementation.This paper proposes a new PV inverter based VVC optimization model and a Pareto front analysis method for maintaining a satisfactory inverter lifetime.First,reliability of the vulnerable DC-link capacitor inside a PV inverter is analyzed,and long-term VVC impact on inverter operational reliability is identified.Second,a multi-objective PV inverter based VVC optimization model is proposed for minimizing both inverter apparent power output and network power loss with a weighting factor.Third,a Pareto front analysis method is developed to visualize the impact of the weighting factor on VVC performance and inverter reliability,thus determining the effective weighting factor to reduce network power loss with expected inverter lifetime.Effectiveness of the proposed VVC optimization model and Pareto front analysis method are verified in a case study.
