作者：王雷，張麒（上海外高橋第三發(fā)電有限責任公司，上海 200137）

摘要：某火電廠(chǎng)原有集中式變頻供電系統為一批大型輔機提供集中調速電源。由于該供電系統為獨立微電網(wǎng)，為維持系統頻率穩定性及滿(mǎn)足輔機變頻運行需要，汽輪機的調節閥門(mén)長(cháng)期處于節流狀態(tài)，尤其是中低負荷區間時(shí)輔機變頻運行所需功率相對汽輪機下降得更快，加劇了節流損失。本文介紹的新型電能轉換技術(shù)屬跨界集成創(chuàng )新，基于現有電力電子變頻技術(shù)和產(chǎn)品，在現有集中變頻供電系統與工頻系統之間，研發(fā)并增設一套新型電能轉換系統，實(shí)現了集中式變頻供電系統與廠(chǎng)用電工頻系統兩個(gè)異頻電網(wǎng)之間的聯(lián)絡(luò )運行，將集中變頻供電系統變化的電壓、頻率經(jīng)轉換后，輸出為可運行于現有工頻系統的交流電源，并將集中變頻供電系統的富裕功率送至現有工頻系統。通過(guò)調節新型電能轉換系統的輸出功率，基本代替汽輪機調節閥門(mén)的調速功能，而且使汽輪機調門(mén)接近全開(kāi)，減小節流損失、提高機組性能。

關(guān)鍵詞：電能轉換；異頻電網(wǎng)互聯(lián)；集中變頻；反向電調門(mén)

Abstract: A centralized variable frequency power system has been built in a power plant to supply common electric power of speed governing operation for a number of large motors. However,the system forms a microgrid which frequency is different from utility power grid, so the turbine regulating valves often operate in throttling state,which not only provide the speed required by motors, but also keep the turbine speed stable.This means a lot of throttling loss, especially when the lower speed need of motors. The paper introduces a new technology of electric power transform based on the existing IGBT technology and product, which a new electric power transform system is developed and applied. The new system is an integrated innovation, successfully interconnects centralized variable frequency power system with utility power grid, converts varying voltage and frequency to nominal voltage and frequency, and transfer spare energy due to turbine valves almost fully open from centralized variable frequency power system to utility power grid. In addition to greatly reducing throttling loss, by adjusting the output power of the new system instead of turbine valves, like a backward acting regulating valve of electric, the system speed can be controlled well. The new system improves the performance of power plant unit.

Key words: Electric power transform; Interconnection between power grids with different frequency;Centralized variable frequency power system;Backward acting electric regulating valve

在線(xiàn)預覽：一種新型電能轉換技術(shù)及其應用

摘自《自動(dòng)化博覽》2019年11月刊