Vector control of pmsm in circulation pump application and an adaptive approach for EEI optimization

Considering that the pumps have a 20% share in the energy consumption in the world, the magnitude of the energy consumption caused by the old technology fixed cycle pumps is revealed. As take decision by the European Union, after 2013, 95% of circulation pumps of fixed cycle circulation pumps are prohibited. The annual energy savings that can be achieved by using a new generation wet rotor pump in Europe is approximately 23 billion kWh. In the member states of the European Union, the circulation pumps can not be sold if the energy efficiency index is above 0.23. In this case, the pump manufacturers have tended to use higher efficiency electric motors and drive systems in their pumps in order to hold onto the market. Asynchronous motors used in old generation circulation pumps were replaced with high efficiency permanent magnet synchronous motors in order to obtain high efficiency in the motor. In order to reduce friction in the engine and to facilitate cooling, in circulation pump applications, the design of the motor is generally preferred in the design of wet rotor permanent magnet synchronous motor. In this structure, the rotor and stator are separated from each other by a case and the rotor rotates in water. Within the scope of the thesis, energy efficiency index has been reduced with the control algorithm developed for circulation pumps with an energy efficiency index greater than 0.2. This control algorithm changes the reference speed of the motor according to the flow rate by integrating the speed reference table created for the determined flow values into the vector control method, thus ensuring more efficient operation of the pump. In the second part of the thesis, the structures and control types of new generation high efficiency circulation pumps are examined. Basic pump information and hydraulic definitions are provided. In the third part, permanent magnet synchronous motors used in new generation high efficiency circulation pumps are examined. After examining the properties of the magnet types used, permanent magnet motors are classified. After this classification, the measurement methods of the parameters of the PMSM are explained and the parameters of the motor used within the scope of the thesis were measured with these methods. Detailed mathematical models of PMSM are explained at the end of this section. In the fourth part, vector control method is examined. Basic information about vector control, sensor vector control, open loop flux prediction for sensorless vector control method are given. The algorithm that estimates the pump parameters such as flow rate and head height with the q axis flow developed in the thesis is explained. At the end of this section, the hardware structure of the control card used is introduced and circuit diagrams of the relevant parts are given. In the fifth part of the thesis, how to calculate the wet rotor circulation pump energy efficiency index according to DIN EN 16297-1 is explained in detail. Then, the details and implementation of the developed EEI optimization method are explained step by step. Proposed control method in this study was named as semi-analytical because at the beginning of the analysis experimental data were required. The basis of the control algorithm is based on the creation of a speed lookup table with different flow rate references for the PMSM to optimize the EEI value. In the last part of the thesis, in the fifth chapter, the reference speed table obtained by numerical analysis in Mathcad environment was integrated into the vector control method and tested on the pump. By combining the developed control algorithm with FOC control, the efficiency of PMSM in pump application is increased. Moreover, with the analysis program developed in mathcad environment, the number of experimental measurements required for EEI calculation in pump applications has been reduced. For the developed control algorithm, consistency of the analysis results were verified with experimental measurements. The lookup table (flow-velocity) generated by Mathcad analysis was applied to the wet rotor circulation pumps software of a pump company producing all over the world. Thanks to the control algorithm developed instead of the standard control algorithm used, the EEI value of the pumps has been reduced and sold to the world market.