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In this article, in order to improve the power quality and decrease the consumed power of an induction motor (IM), which is supplied by an alternate battery-powered system, an algorithm that can be used to save its energy consumption has been proposed. The control mechanism is used to reduce the wasted energy caused by IMs start-up current based on bounding its optimal starting voltage. The proposed algorithm includes two parts: First, use branch-and-bound theory to derive the control rule of the IMs start voltage and give corresponding offline calculation procedure framework. Second, according to the control rule, adjust online voltage of the zinc–bromine flow battery, which is used to feed the IM. Due to the proposed approach, the minimum start-up voltage of the battery-powered system can be predicted and by which one the IMs surge current has been suppressed online. Moreover, the relationship of the output voltage of the battery and inverter supply to the load current has been derived by modeling the battery-powered system. The experiments demonstrate that compared with before optimization, the amount of energy consumption of the IM supplied by zinc–bromine flow battery decreases by 8.5% and corresponding indicator parameters of the power quality can reach the standard IEC TS62749-2015. [ABSTRACT FROM AUTHOR]

An approach for saving energy consumption of the electric submersible motor (ESM) has been proposed based on combining the thermal field model with electrical control. For decreasing the high energy consumption that has become increasingly serious in oil fields, one of our works is to increase the identification accuracy of the ESM temperature by overcoming the influence of the long cable. The thermal field model of the long cable has been derived and used to correct the equivalent circuit of the ESM first; then the procedure that can be used to identify the rotor temperature is given based on improving the calculation accuracy and efficiency of the rotor slot harmonics. The control rule for modulating the inverter frequency to match the actual oil production was simulated by summarizing the experiment results. Theory analysis and experiments denote that the average identification error of the rotor temperature has been controlled within 1° C and the average power consumption of the ESM may be decreased for about 12% by the proposed approach. This work can effectively reduce the power consumption and provide overheat protection of the ESM. [ABSTRACT FROM AUTHOR]