Abstract—This paper first analyzes how thermodynamic system state parameters are affected when main steam’s pressure changes under sliding pressure operation .Then a new state distribution equation of sliding pressure operation based on thermo-economy equation of state of thermal power unit is given .With the help of this equation, a new algorithm is proposed to determine the state parameters distribution for variable working condition under sliding pressure operation. Experiment of one supercritical unit is provided to validate the effectiveness of our approach under sliding pressure operation. Simulation results show that this algorithm is beneficial for analyzing the security and economy of thermal power unit with deep fast variable loads. It also has vital important significance for thermal power unit to develop its peak shaving ability.

Index Terms—Sliding pressure, variable working ondition, thermo-economy, thermal power unit.

Wei Liu, Wei Wang, Deliang Zeng, and Taihuang Chang are with North China Electric Power University,Beijing,102206, China (e-mail: lw2359@163.com)
Jizhen Liu was with Huazhong University of Science & Technology. Wuhan, 430074 China. He is now with North China Electric Power University, Beijing, 102206, China