Energy-saving Transformation Of Circulating Water Pump In Thermal Power Plant

Energy-saving and reducing consumption has become a daily topic of contact and talk about our lives and work.With the continuous promotion of energy saving and consumption reduction,it has become the direction of power generation enterprises to minimize the power consumption rate of power plants and enhance the competitiveness of electricity prices.As a high-power equipment in conventional operation of power plant,circulating water pump has been in the state of excessive output for a long time,which consumes power for nothing and increases the energy consumption of unit power generation.Therefore,when the unit load or environmental temperature is reduced,power plant can achieve the purpose of pump energy saving and consumption reduction by trying to reduce the speed of circulating water pump while also meeting the cooling water demand of the unit.Adjusting the speed of circulating water pump motor has become the optimal choice for energy saving,variable frequency speed regulation and variable pole speed regulation are the most widely used speed regulation methods in power plants.Therefore,this paper selects the practical problem of excessive consumption of power supply by circulating water pump in thermal power plant for a long time,and provides a reference for the motor transformation of each power plant through the energy-saving transformation measures of water pump,software simulation and transformation cases,etc.Based on the reason that the water supply of the circulating pump can be reduced,the motor directly connected with the pump can reduce the current of the motor under the premise of not increasing the voltage by means of reducing the speed of the motor,so as to achieve the effect of energy-saving transformation.At home and abroad,the reduction of energy consumption of induction motors is generally adopted under the frequency or pole logarithmic change of the speed regulation mode,that is,frequency conversion or pole change transformation.The speed regulation mode under the frequency change mode needs to install the frequency conversion device to realize the speed conversion,which has the advantages of smooth speed regulation,larger speed regulation area,more application motor types,and so on.At present,high and low speed has become the first choice for many power plants because of its advantages of low cost and good economic effect.Combined with the structure of circulating pump,working characteristic curve and speed regulation theory,this paper compares the energy-saving methods between the motor side and the pump side,and chooses to transform the motor with frequency conversion and pole-changing speed regulation.Then the ANSYS software and MATLAB software are used to simulate the circulating water pump speed regulation system.The simulation results show that the influence of the speed regulation mode on the stator current,speed and magnetic density of the motor is directly understood,which provides theoretical support and effect verification for the energy saving transformation.The safety and energy-saving effect of the retrofit is verified by combining the operational data of the retrofit.Through the analysis of the ways of energy-saving transformation,the key points under various ways of energy-saving transformation are found.The simulation software is used to modify the motor parameters and compare the output curves to see the effect of speed regulation.The stator current of the motor decreases and the output torque of the motor decreases.The running data of the motor before and after retrofit is recorded,and the running current after the speed regulation is reduced,and the output of the motor meets the operation demand of the unit.Compare the cost and return time of motor speed regulation reform,and analyze the advantages and disadvantages of various speed regulation methods.Finally,the method of decreasing the current of circulating water pump in thermal power plant is found,which provides a reference for the energy-saving transformation of motor.