| The reactor main coolant pump(RCP)is the most important active device in the PWR which is described as the heart of the reactor.At present our country is developing the third generation of nuclear power technology.The Advanced Passive PWR(AP1000)is quite a outstanding type from all of these nuclear power plant.The RCP for AP1000 is adopted of a shielding pump with unique design features and requirements.In order to guarantee the continuous and reliable operation of the main coolant pump,as well as to guarantee the safety operation requirements of reactor,the start-up and control system for RCP must be designed to meet the limits including to supply power pump,at the same time to realize start-up and speed control functions.This thesis mainly study in-depth on the start-up and control system of RCP which chooses the Variable Frequency Drive(VFD)for the first time.Firstly basing on the AP1000 designing features and function requirements for RCP,the article discusses which requirements the start-up and control system should satisfy.Thence to summarize the reasons for choosing VFD through the comparative.Then we analysis of the frequency conversion control’s conformance to the design requirements and which technical indicators should to be met.And then the article go into details of VFD which is adopted by RCP including discussing the structure and characteristics,studying the operation mode(E.g cooling,charging,regenerative braking operation),and discussing the control and logic analysis.Finally with the help of cold functional test which was carried out on the main pump frequency conversion control for the test of performance,the article verify the control ability and the effect of VFD as well as some problems and hazards.On the basis of this,the results are analyzed including reliability,and the continuous operation risks are discussed to put forward improvements.To sum up,with the use of VFD as a start and control scheme for RCP in AP1000,this paper has made a lot of research which have rich practical significances as follows: to study the design requirements which the start-up and control system must be meet,to conclude the advantages of frequency conversion control and its technical requirements,to study in-depth of the structure and function of the VFD as well as the operation modes and control logic,to verity the performance of the VFD by cold function test,to complete the reliability analysis,to discuss the problems and risks with finally putting forward the improvement opinions. |
