Boiler steam temperature control device, system and method

Abstract

The invention relates to the field of thermal control, and discloses a device, system and method for controlling a steam temperature of a boiler. The device for controlling the steam temperature of the boiler comprises a main PID (proportional-integral-differential) regulator and an auxiliary PID regulator which are connected in series, and further comprises a parameter conversion unit connected with the auxiliary PID regulator, wherein the main PID regulator is configured to output a desuperheater post-temperature setting value according to the received main steam temperature value and main steam temperature setting value; the parameter conversion unit is configured to output a proportional band and first integral time to the auxiliary PID regulator according to the received desuperheating water main pipe pressure; the auxiliary PID regulator is configured to output a desuperheating water adjustment control signal to a desuperheating water adjusting executing mechanism according to the received desuperheater post-temperature value, the desuperheater post-temperature setting value, the proportional band and the first integral time so as to control the openness of a desuperheating water adjusting valve. By the technical scheme adopted by the invention, variable-parameter adjusting is achieved in control of the desuperheating water adjusting valve, and the control quality of the steam temperature is improved.

Description

technical field [0001] The invention relates to the field of thermal control, in particular to a boiler steam temperature control device, system and method. Background technique [0002] The main function of the boiler steam temperature control system of thermal power generating units is to maintain the main steam temperature of the boiler within the allowable range by adjusting the flow rate of desuperheating water. The steam temperature control system of coal-fired boiler includes: controller, operation station, thermal instrument for measuring physical parameters, desuperheating water flow regulating valve actuator, etc. The controller adopts the cascade PID control method composed of the main regulator and the sub-regulator. The cascade control includes the sub-loop controlling the leading signal (temperature after the desuperheater) and the main loop controlling the main signal (main steam temperature). loop. When the main steam temperature deviates from the given val...

AI Technical Summary

Problems solved by technology

When the regulator output is in the invalid control area, once the reverse deviation occurs, the actuator still stays at the limit position and cannot immediately make corresponding changes with the deviation reverse, then the system will lose control, resulting in deterioration of control performance

[0005] For the above technical problems, there is no good solution in the prior art

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