汽轮机冷态启动时X准则的控制优化

王雨

摘 要：京能集团北京京西燃气热电有限公司使用的汽轮机为上海汽轮机厂生产的LZC（B）278.8-12.9/0.4/548/540型汽轮机，汽轮机型式为单轴反动式、高中压合缸、双缸双排汽、三压、再热、无回热、凝汽/抽汽/背压式，其配有西门子F级燃机，为燃气-蒸汽联合循环机组。汽轮机高中压部分为双层结构，采用高中压整体内缸，叶片反流布置，同时其采用节流调节，无调节级，整个通流部分共有50级。本文通过分析这种汽轮机启动冲转过程中X准则和主蒸汽温度的关系，以合理控制主蒸汽温度，使汽轮机快速启动，减少开机时间和开机成本，这对同类型汽轮机顺利启动并网及安全、经济运行具有重要的意义。

关键词：汽轮机;X准则;主蒸汽温度;冷态启动;经济运行

中图分类号：TM621文献标识码：A文章编号：1003-5168（2021）02-0137-03

Control Optimization of X Criterion During Cold Start of Steam Turbine

WANG Yu

（Beijing Jingxi Gas-fired Thermal Power Co.， Ltd.， Powerbeijing Group，Beijing 100041）

Abstract： The steam turbine used by Beijing Jingxi Gas-fired Thermal Power Co.， Ltd. of Powerbeijing Group is the LZC （B） 278.8-12.9/0.4/548/540 steam turbine produced by Shanghai Steam Turbine Factory， the turbine type is single-shaft reaction type， high and medium pressure combined cylinder， double cylinder and double exhaust steam， triple pressure， reheat， no heat recovery， condensing steam/extraction steam/back pressure type， it is equipped with Siemens F-class gas turbine， which is a gas-steam combined cycle unit. The high and medium pressure part of the steam turbine has a double-layer structure， adopts a high and medium pressure integral inner cylinder， and the blades are arranged in reverse flow， at the same time， it adopts throttling adjustment， has no adjustment stage， and the entire flow part has a total of 50 stages. This paper analyzed the relationship between the X criterion and the main steam temperature during the start-up and impulse rotation of this kind of steam turbine， in order to reasonably control the main steam temperature， so that the steam turbine couid be started quickly， reducing the startup time and startup cost，This is of great significance for the smooth start-up and grid connection and safe and economic operation of the same type of steam turbines.

Keywords： steam turbine;X criterion;main steam temperature;cold start; economic operation

汽輪机启动是一个不稳定的加热过程，进行合理经济的启动，就是寻求合理的加热方式，使启动过程中汽轮机各部分的热应力处于允许范围内，尽快把机组的金属温度均匀地提高到工作温度，使其进入正常运行状态[1]。如图1所示，汽轮机的启动过程均遵循以下步骤：暖管、暖阀;冲车至暖机转速;暖机;升速至额定转速;额定转速暖机;并网;低负荷暖机;带至额定负荷。

图1中，对于不同曲线来说，Y轴代表不同参数。其中，流量单位为kg/s，其他参数的单位为%。

每一步都与X准则及主蒸汽温度相关，启动过程中暖机时间的长短和效果决定了机组启动是否为合理经济启动，其包括启动方式的选择、启动参数的选择、升温升压率的控制等。……