Dynamic characteristics and control method of the solar-coal energy complementary system

Abstract

The solar-coal energy complementary technology is an effective way to use solar energy for power generation. In this work, a 330 MW coal-fired power generation unit, with an integrated solar field system, was studied to improve solar energy utilization efficiency and control performance. The dynamic mathematical model of the system was established using a lumped parameter method; the maximum relative error was found to be less than 5 %. Different coupling methods for the solar thermal system and coal-fired power unit were studied, and the dynamic characteristics of the unit under different solar radiation intensities were obtained. Finally, a coordinated control system was proposed based on the multiscale decomposition of load commands. The results show that the new coordinated control system showed more flexibility and less fluctuation of power during regulation. It has the best control effect, with the integral of the absolute value of the error criterion reaching 890.8 and 795 in step and slope experiments, respectively, and the integral of time multiplied by the squared error criterion reaching 4.172 × 105 and 3.043 × 105, respectively. This study successfully demonstrates the effective use of solar-coal energy complementary technology and provides an important reference for future work.