汽轮发电机功率-负荷不平衡保护仿真分析  

Simulation of power-load unbalanced protection for turbo-generator

作　　者：何青[1] 李国庆 王立健 陶向宇 HE Qing;LI Guoqing;WANG Lijian;TAO Xiangyu(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China;China Electric Power Research Institute Co.,Ltd.,Beijing 100192,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,北京102206 [2]中国电力科学研究院有限公司,北京100192

出　　处：《热力发电》2018年第11期102-108,共7页Thermal Power Generation

基　　金：国家自然科学基金项目(51276059);中央高校基本科研业务费专项资金(2017XS050)~~

摘　　要：汽轮发电机组功率-负荷不平衡保护(PLU)可防止汽轮机转子超速,但不必要的保护动作易引起机组跳闸等事故,本文根据汽轮机的理论模型,建立了超超临界1 050 MW机组PLU系统的仿真模型,模拟机组甩全负荷时有PLU和无PLU情况下机组超速保护动作以及汽轮机转子转速的变化,并进行分析比较。仿真结果表明:机组PLU和超速保护控制(OPC)均能起到超速保护效果;在甩全负荷时,只有OPC的系统达到的最高转速(3 192 r/min)高于同时有OPC和PLU的系统最高转速(3 150 r/min),有PLU和OPC的系统比只有OPC的系统早动作仅约0.16 s;PLU的超速保护功能与OPC功能重复,同时PLU可能出现的误动会引发严重事故。因此,如果汽轮发电机组同时装有OPC和PLU,且PLU仅起防止机组超速作用,则建议在优化OPC逻辑的前提下可以取消PLU。Power-load unbalanced(PLU)protection of turbine generator can prevent overspeed of the turbine,but unnecessary protection action easily causes unit tripping and other accidents.According to the theoretical model of steam turbine,the PLU simulation model of an ultra-supercritical 1 050 MW unit was established and applied to analyze the overspeed protection action and the variations of the rotor speed of the unit under conditions with full load rejection.The simulation results show that,both the PLU of the unit and the overspeed protection control(OPC)can realize overspeed protection.The system with OPC reached the maximum speed(3 192 r/min),which was higher than that of the system with OPC and PLU(3 150 r/min)when full load rejection took place,and the system with PLU and OPC only actioned about 0.16 s earlier than the system with OPC.It can be said that the overspeed protection function of the PLU is overlapped with OPC in this unit,and it is possible for the PLU to cause serious accidents due to misoperation.Therefore,if the turbo-generator is equipped with both OPC and PLU,and the PLU only acts to prevent overspeed of the unit,it is recommended that the PLU can be eliminated on the premise of optimizing the OPC logic.

关 键 词：汽轮发电机 功率-负荷不平衡保护 超速保护 转子转速 仿真分析 

分 类 号：TM721[电气工程—电力系统及自动化]