Cold source temperature control method and device of flue gas waste heat recovery device

The invention relates to a cold source temperature control method of a flue gas waste heat recovery device. The method mainly comprises the steps of parameter collection, data processing, fuzzy reasoning, controlled quantity outputting, controlling execution and the like. The method specifically comprises the steps of: calculating a temperature error e and a temperature difference change ec with a reference set temperature by collecting parameters such as cold water temperature, hot water temperature, temperature of a mixed water tank, heat exchange wall temperature and exit gas temperature in the flue gas waste heat recovery device; and then, obtaining control parameters by fuzzy reasoning, and adjusting the cold source temperature by controlling a cold source water electric adjusting executor and a flowback water electric adjusting executor through the parameters. According to the invention, with the adoption of an advanced fuzzy predicting method, deviation, size change and direction as well as time relationship of the controlled volume are effectively pre-compensated according to a fuzzy rule established by real time identification of the system, so that short of adjustment or over-adjustment is prevented, the influence to the performance of the control system due to great inertia and large hysteresis in the controlled process is improved, and the control quality is improved.