The application provides a
coupling system and a control method for integrating high-medium temperature
energy storage to improve the flexibility of a
coal-fired unit, wherein the
coupling system comprises a
coal-fired unit and a high-medium temperature
energy storage system; the high-medium temperature
energy storage system comprises a cold-hot energy storage medium tank, a cold-hot energy storage medium tank outlet regulating valve, a cold-hot energy storage medium pump, a high-medium temperature
heat exchanger and other devices; in the energy storage process, the medium at the inlet of the medium-pressure cylinder is taken out and sent to the high-medium temperature energy storage system, the medium after heat release is sent to the outlet of the
deaerator, and the condensate water is corrected at the same time, so as to reduce the minimum load of the
coal-fired unit; in the energy release process, a
load distribution module is designed, the work amount of the coal-fired unit boiler coordination system is reset, part of the medium at the inlet of the
deaerator is taken out and sent to the high-medium temperature energy storage system to generate steam, then the steam enters the high-pressure cylinder exhaust or the low-pressure cylinder inlet to work and improve the load change amount of the whole unit, and the
variable load rate of the coal-fired unit is accelerated. The application reduces the minimum load of the coal-fired unit and improves the
variable load rate of the coal-fired unit, and the flexibility of the coal-fired unit is obviously improved.