Research And Practice Of AGC Control Method In A Hydropower Plant

The hydropower units have the advantages of flexible response and fast regulation.Which capable for peak-time regulation and frequency modulation in the power grid.In order to ensure the stability of power grid frequency and meet the requirements of tracking load curve and tie line power control,the power dispatching department adjusts the active power of generator set in real time through automatic generation control(AGC).In order to improve the safety and stability of the power grid,the regional power regulatory setors have issued the implementation rules for the management of grid connected power plants and the implementation rules for the management of auxiliary services of grid connected power plants(hereinafter referred to as the "two rules"),which have strict requirements on the AGC regulation process of hydropower units and formulated the compensation and assessment mechanism.Many hydropower plants are often held accountable by the power grid dispatching department because the AGC regulation speed,accuracy and other performance indicators do not meet the relevant requirements of the "two rules",which brings great pressure to the production and operation of power plants.Taking a hydropower plant as an example,this paper studies the "two detailed rules" and relevant technical standards,the technical requirements of the national energy regulatory and dispatching department for AGC of hydropower units,the AGC assessment and compensation regulations,and analyzes the main factors affecting the large amount of electricity assessed by AGC but the small amount of compensation electricity of the hydropower plant:first,the inconsistency between the power plant and the dispatching data and the deviation in the accuracy of calculation,Second,the adjustment speed is too slow and the adjustment accuracy does not meet the requirements.In this paper,a hydropower plant directly commissioned in Hunan Province is studied,and the consistency between the power plant and the dispatching data is analyzed and tested;The "rough adjustment" is adopted to improve the time delay of each link of the control system.On the premise of ensuring the reliability and stability of the adjustment system,the response time delay of each link is reduced and the adjustment speed of AGC is improved;"Fine regulation" is adopted to improve the control strategy and control parameters of computer monitoring system and governor system,so as to improve the AGC response performance,regulation quality and regulation accuracy of hydropower units;This paper studies the power regulation characteristics of hydropower units,grasps the performance of hydropower units under different working conditions and different constraints,ensures that the units have good AGC regulation performance under all working conditions,and meets the assessment requirements of "two rules" as far as possible.In addition,combined with the field experiment,the problems existing in the practical application of the "two rules" are analyzed,and the improvement measures are put forward in the aspects of AGC regulation performance index,regulation speed calculation formula and calculation method.Through the application practice of Wanmipo hydropower plant,it is proved that after the AGC control performance and relevant parameters are improved according to the requirements of the "two rules",the AGC power regulation speed is greatly improved,the AGC assessment shows a decreasing trend and is stable in a low range,the compensation shows an increasing trend,and the compensation amount changes from less than the assessment amount to more than the assessment amount,effectively solving the serious problem of AGC power assessment,At the same time,it also brings good compensation income to the power plant,plays a key role in giving full play to the auxiliary services to obtain value-added electricity in the operation of the power plant,and realizing the transformation of the unit operation of Wanmipo hydropower plant from "electricity type" to"electricity type",and provides better improvement ideas for other hydropower plants with similar problems.