Digital electrichydraulic control system for generating plant turboset

Abstract

The invention relates to a digital electro-hydraulic control system used for a power station steam turbine set. The digital electro-hydraulic control system comprises a workstation, a control processor, an overspeed protective device, a valve actuating clamping piece, a servo valve, an oil servo-motor and a steam turbine which is provided with an intermediate-pressure cylinder provided with an intermediate pressure adjusting valve and a high pressure cylinder provided with a high pressure main throttle valve and a high pressure adjusting valve. The invention is characterized in that: the control processor also comprises a control unit which receives a signal from the overspeed protective device, calculates and processes the signal, and transmits the signal to the overspeed protective device to control the opening and closing of the intermediate pressure adjusting valve and the high pressure adjusting valve. The invention also discloses a method for controlling the intermediate pressure adjusting valve of the digital electro-hydraulic control system used for the power station steam turbine set. Because the technical proposal is adopted, the defects of the prior control system are completely overcomed, the control system is safe and reliable, the program control for rotating speed and load of the set can be more accurate, switching speed of a TV / GV causes small wave motion, and the characteristic of quick response of the set is also improved at the same time.

Description

technical field [0001] The invention relates to an automatic control system for a steam turbine set in a power station, in particular to a digital electro-hydraulic control system (DEH) for a 600MW steam turbine set. Background technique [0002] Steam turbine is a large power equipment with high temperature, high pressure and high speed rotation. The steam turbine digital electro-hydraulic control system (DEH) is an indispensable part of the steam turbine generator set in a power station, and is the regulator controller for the start, stop, normal operation and accident conditions of the steam turbine. The electro-hydraulic control system composed of DEH system and EH system realizes the control of the speed, load and pressure of the turbine generator set by controlling the opening of the main steam valve and the regulating valve of the steam turbine. [0003] The current steam turbine control system mainly consists of the following types: the first is a 200MW unit, which ...

AI Technical Summary

Problems solved by technology

The main disadvantage of this system is that the PENTIUM industrial controller PC is easily attacked by viruses, has poor specificity and poor stability; the overspeed protection part is due to its rapidity, and the control logic processing is completely completed by hard wiring, and the configuration is cumbersome and complicated; The hard-handed operation of the system brings inconvenience to the maintenance work of relevant personnel, increases the potential source of hardware failure, and is increasingly unable to adapt to the development of power plant automation level

The second is the control system of the 300MW unit and the 600MW subcritical unit. The control is designed and completed using the control strategy of the high-pressure cylinder starting method, that is, before the unit starts, the medium-pressure valve (IV) is fully opened, and the high-pressure main (TV) control speed reaches TV / GV (high-pressure main steam valve / high-pressure regulating valve) valve switching speed. After TV / GV valve switching, the high-pressure regulating valve GV controls the speed and load of the steam turbine. The main disadvantage of using this control method is: the unit The start-up time is relatively long, when the unit TV / GV valve switches the speed, the speed fluctuation is relatively large, and the quick response ability of the unit after load shedding is poor, and the control accuracy is not high enough

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