Design and application of  new grid-connected energy regenerative system
SU Xiangwei1, JIA Aimin1, LV Xiaodong2
(1. College of Electrical Engineering, Zhejiang University, Hangzhou 310027,China; 2. Hangzhou Zheda Sun Electric Co., Ltd.,  Hangzhou 310027,china)
Abstract: Aiming at the loss of energy of the traditional elevator, which using brake resistor, a new gridconnected energy regenerative system was designed. The new gridconnected energy regenerative system, including its structure, working principle and application field, was comprehensively analyzed and investigated. Based on traditional threephase bridge circuit and double closedloop control algorithm, the control of gridconnected energy regenerative system was carried out. Further more, in order to improve the DC voltage availability and expand the applicable scope of the system, the space vector pulse width modulation algorithm was adopted. At last, a 22 kW gridconnected energy regenerative system was designed and built, and was successfully applied to the OTIS elevator. The experimental results show that the current THD is low to 3.2%, and the system efficiency reaches as high as 96% with better dynamic response. In the practical application, the system is robust and energy saving effect is remarkable.
Key words: energy regenerative; gridconnected; space vector pulse width modulation (SVPWM); DC voltage availability; total harmonic distortion(THD)