Control Performance Quality Research Articles

Maximum Energy Output of a DFIG Wind Turbine Using an Improved MPPT-Curve Method

A new method is proposed for obtaining the maximum power output of a doubly-fed induction generator (DFIG) wind turbine to control the rotor- and grid-side converters. The efficiency of maximum power point tracking that is obtained by the proposed method is theoretically guaranteed under assumptions that represent physical conditions. Several control parameters may be adjusted to ensure the quality of control performance. In particular, a DFIG state-space model and a control technique based on the Lyapunov function are adopted to derive the control method. The effectiveness of the proposed method is verified via numerical simulations of a 1.5-MW DFIG wind turbine using MATLAB/Simulink. The simulation results show that when the proposed method is used, the wind turbine is capable of properly tracking the optimal operation point; furthermore, the generator’s available energy output is higher when the proposed method is used than it is when the conventional method is used instead.

Variable Deadband Sampling and T-S Fuzzy PID Co-Design for Optimizing QoS and QoP of Wireless Networked Control Systems

Variable deadband sampling is used in wireless networked control systems to reduce the network message. In this paper the T-S fuzzy PID with variable deadband sampling is designed to optimize the quality of network services and the quality of control performance in closed control loop. Furthermore, Kalman filtering algorithms dealing with variable deadband sampling are considered in the paper. The comparison results of proposed method and PID with period sampling are presented based on the extensive simulations by using TrueTime 1.5 toolbox for Matlab/simulink, and the simulation results verify the effectiveness of the proposed method.

Research of H∞ Robust Control for the Giant Die Forging Hydraulic Press’s Synchronous Control System under the Uncertainty Coefficient

The giant hydraulic die press is our country national defense and the infrastructure essential equipment, the synchronous control system is the essential device to the giant forging hydraulic press, its synchronization control performance quality is good or bad will directly determine the quality of the product. This article through the proof of the theorem, gives the specific steps to achieve H∞ robust control algorithm. The simulation results show that: this control strategy has good inhibition to the change of system parameters, robustness is very strong, can well eliminate the system synchronization error.

A synthesizing control model of networked control systems to guarantee QoP and QoS

The whole performance of the networked control system (NCSs) depends on two interaction factors, namely the quality of control performance (QoP) and quality of network service (QoS). So, to optimize the whole performance of NCSs, the problem of guaranteeing QoP and QoS plays an important role in the design of NCSs. However, up to now, little work has been done in this field. In this paper, a synthesizing control model of NCSs to guarantee QoP and QoS is proposed, and a feasible condition of optimizing whole performance of NCSs is also suggested. Finally, the simulation results show that the proposed model is effective.