Quick load reducing method of unit-system generator set under emergency situations

Abstract

The invention relates to a unit-system generator set control technology, and discloses a quick load reducing method of a unit-system generator set under emergency situations. Under the emergency situations that fuel of a gas-fired boiler is significantly reduced or main auxiliary equipment breaks down, safe and stable load reducing control is achieved, and then normal adjustment on the hearth pressure, the air volume and the steam turbine rotation speed is restored. According to the method, when the set runs, if a set control system detects and judges that a current automatic load control loop is in the load reducing process, the set is controlled to gradually decrease the switch-on degree of a fuel adjusting valve in sequence layer by layer, and meanwhile the actions, enabling the switch-on degree to be increased, of a boiler air feeder adjusting baffle, an induced draft fan adjusting baffle, a combustion-supporting hot air valve and a steam turbine speed adjusting air valve adjusting valve are prevented; after the switch-on degree is immediately decreased to a certain degree, the switch-on degree is decreased at the gradually decreasing rate according to changes of the stream flow and the generating capacity of the set so as to decrease the air volume and the steam turbine rotation speed, and lastly the set load achieves a balance state.

Description

technical field [0001] The invention relates to the control technology of a unitary generating set, in particular to a method for quickly reducing load of a unitary generating set in an emergency. Background technique [0002] With the increase of the capacity of generating sets in modern society, boilers, steam turbines, and generators are increasingly becoming a whole. In order to realize the safe and economical operation of the units, the unit system control of centralized monitoring and coordinated operation of machines, furnaces, and electricity has become an integrated system. a trend. The advantage of the unit system generator set is that the system is simple, the control is centralized, and the connection is close. The disadvantage is that the flexibility of the electrical equipment of the generator is poor. When any important auxiliary equipment fails, it will affect the normal operation of the entire unit. [0003] Unit gas boilers use blast furnace gas from ironm...

AI Technical Summary

Problems solved by technology

However, when the main auxiliary equipment of the unit suddenly breaks down, causing the load bearing capacity of the unit to drop, since these auxiliary units can generally carry 50-60% of the rated load when operating alone, when one of the two auxiliary units operating in parallel trips ( For example, if one of the two running blowers or induced draft fans of the gas-fired boiler fails suddenly), it will cause the boiler steam load to drop sharply, the pressure in the furnace to change drastically, and the automatic adjustment of fuel, air volume and furnace pressure to fluctuate greatly, etc. Improper handling of this critical situation can easily cause major safety accidents such as boiler explosion and furnace wall collapse.

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