作者机构：
[李敬东; 郭芳; 戴陶珍; 唐跃进] Huazhong Univ. of Sci. and Technol., Wuhan 430074, China;Changsha Univ. of Sci. and Technol., Changsha 410077, China;[周羽生] Huazhong Univ. of Sci. and Technol., Wuhan 430074, China, Changsha Univ. of Sci. and Technol., Changsha 410077, China
通讯机构：
[Zhou, Y.-S.] H;Huazhong Univ. of Sci. and Technol., Wuhan 430074, China
摘要：
Under pulsed over-currents with different durations, quench and recovery behaviors of Bi-2223/Ag HTS tapes have been observed. The experiment is carried out using a pulsed circuit. The HTS tapes are immersed in liquid nitrogen bath. The durations of the pulsed currents fed to HTS tapes are 2.78 ms, 1.97 ms, 1.58 ms, 1.22 ms, 1.11 ms and 0.91 ms, respectively. In order to confirm the critical current of the tapes, DC current is fed to the tapes firstly. The magnitude of the pulsed currents is about 100 A, which is about three times of the critical current of the tapes. The experimental result shows that the normal voltage generated by the over-current disappears fast after the end of the pulsed over-current. As the duration of the pulsed current decreases, the quench and recovery current tends to increase, and larger than the critical current of the tapes, which show that HTS tape has a good superconducting-to-normal conducting recovery characteristic under pulsed current with short duration. These results show that the application of HTS tapes for future pulsed power would be very promising.
摘要：
Quench and recovery characteristics of Bi-2223/Ag high-temperature superconductor (HTS) tapes under oscillating over-currents with different frequencies have been observed. The experiment is carried out using an oscillating circuit consisted of capacitance and inductance, which produces oscillating currents with different frequencies. The HTS tapes are immersed in liquid nitrogen bath. The frequencies of the oscillating currents fed to HTS tapes are 180.8, 333.3, 434.8, 751.9, and 2016.1 Hz, respectively. In order to confirm the critical current of the tapes, dc current is fed to the tapes first. The magnitude of the oscillating currents is from a small current to 179 A, which is 2.5 times larger than the dc critical current of the tapes. The experimental result shows that the normal voltage generated by the over-current disappears fast after the end of the oscillating over-current, which shows that HTS tapes have good superconducting-to-normal conducting recovery characteristics under oscillating current with high frequency. The experimental results will encourage the possibility of the important applications of HTS tapes in pulsed power.
摘要：
A neural network based predictive control strategy for active power filter is presented in this paper. In the strategy, RBF neural network is employed to predict future harmonic compensating current. In order to make the predictive model much simpler and tighter, an adaptive learning algorithm for RBF network is proposed. Based on the model output, Genetic algorithm is introduced to optimize objective function, which generates proper value of control vector. The neural network based predictive algorithm is used in internal model control scheme to compensate for process disturbances, measurement noise and modeling errors. Simulation test under various conditions is implemented. The results show the neural network based predictive control is more effective and feasible than PI control or digit adaptive control.
作者机构：
[周羽生; 粟时平] Department of Electric Power, Changsha University of Sci./Technol., Changsha 410077, China;[周有庆] College of Electrical Engineering, Hunan University, Changsha 410082, China;[苏建成] Hunan Electric Power Company, Changsha 410007, China
