作者机构：
[王耀南; 樊绍胜] Coll. of Elec. and Info. Eng., Hu'nan Univ., Changsha 410082, China;[樊绍胜] Coll. of Elec. and Info. Eng., Changsha Univ of Sci. and Technol., Changsha 410077, China
通讯机构：
Coll. of Elec. and Info. Eng., Hu'nan Univ., China
期刊：
Proceedings of the 2004 IEEE International Conference on Electric Utility Deregulation, Restructuring and Power Technologies (DRPT2004),2004年1:393-397
关键词：
distributed generator systems;high impedance fault;relay agent;power system protection
摘要：
As a result of deregulation, distributed generation (DG) systems with distributed generators installed in the middle or low voltage networks become popular in distribution systems. Traditional protections developed in radial systems are difficult in coordination and in protecting against high impedance fault (HIF), sometimes it may cause nuisance tripping in the DG systems. A decentralized multi-agent based protection with capability of HIF detection, fault location and load shedding for the DG systems is proposed in the paper. Digital relay is designed as a relay agent which is capable of searching for information from other relay agents, interacting with other relay agents and performing tasks of protection with autonomy and cooperating. The agent based protection scheme is also presented. EMTP simulation results show that the proposed agent based protection scheme can remove the influence of load switching operations, protect against HIF, electric shock. The prototype of relay agent is developed, the research is now in progress on testing the prototype in dynamic power system.
期刊：
Proceedings of the 2004 IEEE International Conference on Electric Utility Deregulation, Restructuring and Power Technologies (DRPT2004),2004年1:306-310
摘要：
Power quality is influenced by neutral grounding methods in distribution systems. Optimization for neutral grounding methods is discussed in the paper. Petersen-coil in parallel with high resistance earthed technique has a better performance in safety and power quality than other neutral point grounding techniques. To improve power quality, a novel method for measurement of zero sequence impedance in distribution systems is presented, Petersen-coil inductance is adjusted to compensate the total capacitance, and the resistor which is in parallel with the Petersen-coil is adjusted to control the over-voltage; some other novel techniques for grounding fault feeder protection based on testing the fault resistance or the energy dissipated in the fault point are also presented. The method of Petersen-coil tuning has been developed. Experimental results show that the optimization for neutral grounding methods and the protections proposed can improve the power quality by reducing the over-voltage, the residual current and the grounding fault duration.
作者机构：
[何怡刚] Coll. of Electrical and Info. Eng., Hunan Univ., Changsha 410082, China;[Zeng Z.-Z.] Coll. of Electrical and Info. Eng., Changsha Univ. of Sci. and Technol., Changsha 410077, China;[王小华] Coll. of Electrical and Info. Eng., Hunan Univ., Changsha 410082, China, Coll. of Electrical and Info. Eng., Changsha Univ. of Sci. and Technol., Changsha 410077, China
通讯机构：
[Wang, X.-H.] C;Coll. of Electrical and Info. Eng., , Changsha 410082, China
摘要：
Viscosity is one of the key quantities in Rubber mixing process, online measurement of viscosity is very difficult to achieve. To cope with this problem, a soft sensing approach based on fuzzy modeling is proposed. During fuzzy modeling, T-S fuzzy model is employed to approximate the non-linearity of rubber mixing process, an improved Gustafon-Kessel fuzzy clustering algorithm based on similarity assessing is proposed to determine the optimum number of clusters. All these techniques make the fuzzy model simple and accurate. Based on it, test on BB370 internal mixer is carried out. The results show the proposed approach provides more accurate viscosity prediction than mathematical modeling approach. Compared with laboratory measurement, the error is small and acceptable. It improves production efficiency greatly and lays down the foundation for optimal control of viscosity.
关键词：
diagonal recurrent neural network;predictive control;branch-and-bound optimization;active power filter
摘要：
A diagonal recurrent neural network based predictive control strategy for active power filter is presented in this paper. In the strategy, diagonal recurrent neural network is employed to predict future harmonic compensating current. In order to make the predictive model compact and accurate, an adaptive dynamic back propagation algorithm is proposed to obtain the optimum number of hidden layer neurons. Based on the model output, branch-and-bound optimization method is adopted, which generates proper gating patterns of the inverter switches to maintain tracking of reference current without time delay. The model predictive algorithm is used in internal model control scheme to compensate for process disturbances, measurement noise and modeling errors. The proposed control strategy is applied to compensate the harmonic produced by the variable non-linear load. Simulation results show the diagonal recurrent neural network based predictive controller gives better harmonic compensation performance than digital adaptive controller.
