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Abstract Parallel connected electrical machines drive systems have received significant attention due to their use in special purpose applications. Recently, control of such systems using a single inverter has been considered for improving stability during uneven load conditions on machines. In this paper, a synchronized control strategy for stable operation of dual parallel brushless direct current motors using a single three-phase inverter is proposed. Control of parallel connected brushless direct current motors suffers from instability under different load torques. To obtain the stability, an effective control method based on master-slave strategy is presented. To analysis the stability, the detail model of the proposed system is developed for an electric vehicle propulsion system. Therein, the motor with the highest load or with lagging rotor position is selected as the master and is directly controlled. The effectiveness of the proposed system is demonstrated by a series of case studies in different operation conditions. [ABSTRACT FROM AUTHOR]

A new nonisolated multiinput multioutput dc-dc boost converter is proposed in this paper. This converter is applicable in hybridizing alternative energy sources in electric vehicles. In fact, by hybridization of energy sources, advantages of different sources are achievable. In this converter, the loads power can be flexibly distributed between input sources. Also, charging or discharging of energy storages by other input sources can be controlled properly. The proposed converter has several outputs with different voltage levels which makes it suitable for interfacing to multilevel inverters. Using of a multilevel inverter leads to reduction of voltage harmonics which, consequently, reduces torque ripple of electric motor in electric vehicles. Also, electric vehicles which using dc motor have at least two different dc voltage levels, one for ventilation system and cabin lightening and other for supplying electric motor. The proposed converter has just one inductor. Depending on charging and discharging states of the energy storage system (ESS), two different power operation modes are defined for the converter. In order to design the converter control system, small-signal model for each operation mode is extracted. The validity of the proposed converter and its control performance are verified by simulation and experimental results for different operation conditions. [ABSTRACT FROM AUTHOR]