Research On Stator Heat Issues Caused By Water Blockage In Double Water Internal Cooling Synchronous Condenser

As an important equipment of high voltage power grid,synchronous condenser has the main functions of stabilizing power grid voltage and regulating grid reactive power.The increase in the capacity of the condenser leads to the increase of the winding loss,resulting in a higher internal temperature inside the motor.In order to control the temperature of the motor within the allowable range,it is necessary to adopt an efficient cooling method.The quality of the cooling system determines the service life of the motor,and the stator waterway blockage is the most common fault in the cooling system of the synchronous condenser.Therefore,it is of great significance for the stable operation of condenser to analyze the temperature distribution of the stator waterway when the stator waterway is normal and blocked.In this dissertation,a 300 MVar dual water internal cooling synchronous condenser is taken as the research object.Based on the basic theory of electromagnetic field in the motor,a 2-D eddy current field solution model of the stator bar of the synchronous condenser is established and analyzed,obtaining the distribution of the magnetic line and current density.In order to accurately analyze the stator fluid field and temperature field of the condenser,the resistance increase coefficient and heat source power density of the hollow solid strand of the stator bar are calculated.Based on the characteristics of the flow and heat transfer of the stator water cooling system of the double water internal cooling synchronous condenser,the physical and mathematical models of the 3-D fluid field and temperature field of the stator of the condenser are established.According to the finite volume method,the fluid field and temperature field of the stator in normal operation are calculated,and the distribution laws of the velocity and the temperature of the stator winding and the stator core in the radial ventilation groove of the stator are obtained.Compare the calculated results with the measured results to determine the accuracy of using the finite volume method to study the stator temperature field of the synchronous condenser.In order to solve the problem of stator bar water path blocking,the reason of stator waterway blockage is analyzed and the stator temperature field under different blocking coefficient is simulated.By analyzing the temperature distribution of the stator when the waterway is blocked,the change law of the stator temperature distribution with the blockage coefficient is obtained.To grasp the temperature change of each part of the stator in time,the stator temperature monitoring system of the condenser is established by the temperature measuring meter,temperature sensor and other devices installed in the stator bar.On the basis of the temperature monitoring system,the evaluation index of the stator water cooling system of the tuning condenser is given and the evaluation method of the health state of the system is described.According to the degree of clogging of stator bar waterway,the treatment method after blocking of waterway is analyzed.