Influence of Primary Frequency Regulation Parameters on Performance of a Ultra-supercritical Double Reheat Unit

doi:10.11930/j.issn.1004-9649.201903097

Abstract

Abstract: Primary frequency regulation characteristics of double reheat unit have significant impacts on the operation stability and flexibility of power system due to its complicated flow process and large inertia. Based on the GSE simulation platform, the dynamic simulation models of the ultra-supercritical double reheat generation unit and primary frequency regulation were developed and validated by virtue of the combination of JTopmeret module and self-defined program. Then, the response characteristics of the thermal parameters in the double reheat unit during the primary frequency regulation process were studied. The effects of the load step amplitude and the speed droop on the primary frequency regulation characteristics were analyzed. It is discovered from the results that in the primary frequency regulation process of the double reheat unit, with step increase of the load power the real-time frequency will drop rapidly and DEH turbine control system will immediately take measures during dynamic processes, the real time frequency is less 50 Hz. Once the system reaches steady state, the relative change of flow volume and pressure of the primary and secondary reheat steam will be greater than those of the main steam. During the primary frequency regulation of the double reheat units, the increase of load step amplitude or the reduction of the speed droop, will both boost the dynamic overshoot of the frequency, and prolong the time duration for frequency regulation. Compared with single reheat generation units, the primary frequency control systems of double reheat units demonstrate faster response, whereas their maximum overshoot is larger during the regulation process.

Key words: coal-fired power plant, double reheat, primary frequency regulation, operational flexibility, speed droop, dynamic characteristics

CLC Number:

WANG Zhu, HAN Xiang, XU Lihuan, ZHAO Yongliang, CHONG Daotong. Influence of Primary Frequency Regulation Parameters on Performance of a Ultra-supercritical Double Reheat Unit[J]. Electric Power, 2019, 52(5): 54-62.

Add to citation manager EndNote|Ris|BibTeX

URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201903097

https://www.electricpower.com.cn/EN/Y2019/V52/I5/54

References 21

[1]	CHANG S Y, ZHOU J K, MENG S, et al. Clean coal technologies in China:Current status and future perspectives[J]. Engineering, 2016, 2(4):447-459.
[2]	FRANCO A, DIAZ A R. The future challenges for "clean coal technologies":Joining efficiency increase and pollutant emission control[J]. Energy, 2009, 34(3):348-354.
[3]	ZHOU L Y, XU G, ZHAO S F, et al. Parametric analysis and process optimization of steam cycle in double reheat ultra-supercritical power plants[J]. Applied Thermal Engineering, 2016, 99:652-660.
[4]	王月明, 牟春华, 姚明宇, 等. 二次再热技术发展与应用现状[J]. 热力发电, 2017, 46(8):1-10, 15 WANG Yueming, MU Chunhua, YAO Mingyu, et al. Review of the development and application of double-reheat power generation technology[J]. Thermal power generation, 2017, 46(8):1-10, 15
[5]	OLAUSON J, AYOB M N, BWEGKVIST M, et al. Net load variability in Nordic countries with a highly or fully renewable power system[J]. Nature Energy, 2016, 1(12):16175.
[6]	LU X, MCELROY M B, PENG W, et al. Challenges faced by China compared with the US in developing wind power[J]. Nature Energy, 2016, 1(6):16061.
[7]	舒印彪, 张智刚, 郭剑波, 等. 新能源消纳关键因素分析及解决措施研究[J]. 中国电机工程学报, 2017, 37(1):1-8 SHU Yinbiao, ZHANG Zhigang, GUO Jianbo, et al. Study on key factors and solution of renewable energy accommodation[J]. Proceedings of the CSEE, 2017, 37(1):1-8
[8]	ALIZADEH M I, MOGHADDAM M P, AMJADY N, et al. Flexibility in future power systems with high renewable penetration:A review[J]. Renewable and Sustainable Energy Reviews, 2016, 57:1186-1193.
[9]	黄卫剑, 张曦, 陈世和, 等. 提高火电机组一次调频响应速度[J]. 中国电力, 2011, 44(1):73-77 HUANG Weijian, ZHANG Xi, CHEN Shihe, et al. Enhancing response speed of primary frequency regulation in thermal power unit[J]. Electric Power, 2011, 44(1):73-77
[10]	ZHAO Y L, LIU M, WANG C Y, et al. Increasing operational flexibility of supercritical coal-fired power plants by regulating thermal system configuration during transient processes[J]. Applied Energy, 2018, 228:2375-2386.
[11]	ZHAO Y L, WANG C Y, LIU M, et al. Improving operational flexibility by regulating extraction steam of high-pressure heaters on a 660 MW supercritical coal-fired power plant:A dynamic simulation[J]. Applied Energy, 2018, 212:1295-1309.
[12]	HU Y, ZENG D L, LIU J Z, et al. Dynamic model for controller design of condensate throttling systems[J]. ISA Transactions, 2015, 58:622-628.
[13]	LONG D T, WAND W, YAO C, et al. An experiment-based model of condensate throttling and its utilization in load control of 1000 MW power units[J]. Energy, 2017, 133:941-954.
[14]	WANG W, LIU J Z, ZENG D L, et al. Modeling for condensate throttling and its application on the flexible load control of power plants[J]. Applied Thermal Engineering, 2016, 95:303-310.
[15]	WANG W, LI L, LONG D T, et al. Improved boiler-turbine coordinated control of 1000 MW power units by introducing condensate throttling[J]. Journal of Process Control, 2017, 50:11-18.
[16]	冀川, 许海雷, 李勇. 提高二次再热机组一次调频响应的策略[J]. 电力科技与环保, 2018, 34(6):37-39 JI Chuan, XV Hailei, LI Yong. Method for improving primary frequency response of double reheat steam turbine[J]. Electric Power Technology and Environmental Protection, 2018, 34(6):37-39
[17]	李勇, 许海雷. 凝结水节流参与的1000 MW二次再热机组一次调频控制方法[J]. 电力科技与环保, 2018, 34(6):34-36 LI Yong, XU Hailei. Condensate throttling frequency control method for 1000 MW double reheat units[J]. Electric Power Technology and Environmental Protection, 2018, 34(6):34-36
[18]	WU C, GAO L, XIA J, et al. Analysis of effects on primary frequency control and power grid stability of different control logic[C]//ICIEA 2010:Proceedings of the 5th IEEE conference on industrial electronics and applications,Taichuan, 2010.
[19]	WANG C Y, LIU M, ZHAO Y L, et al. Dynamic modeling and operation optimization for the cold end system of thermal power plants during transient processes[J]. Energy, 2018, 145:734-746.
[20]	吴雪莲, 李兆伟, 蒋望, 等. 并网发电机组的一次调频性能评价方法综述[J]. 电子设计工程, 2018, 26(19):171-177 WU Xuelian, LI Zhaowei, JIANG Wang, et al. A review on the evaluation methods of primary frequency modulation performance of grid-connected generator[J]. Electronic Design Engineering, 2018, 26(19):171-177
[21]	王永庆, 赵嘉, 曹越, 等. 超临界机组及其一次调频控制系统的辨识与仿真[J]. 热能动力工程, 2018, 33(2):111-116 WANG Yongqing, ZHAO Jia, CAO Yue, et al. Identification and simulation of a supercritical unit and its primary frequency modulation and control system[J]. Journal of Engineering for Thermal Energy and Power, 2018, 33(2):111-116