Power factor correction of an electrical drive system based on multiphase machines

International audienceThis paper deals with the energy efficiency improvement of an electrical drive which can be used both in wind energy conversion or motor drive applications. A power factor (PF) control scheme is presented allowing energy efficiency enhancement and optimization in high power variable-speed drives based on multiphase machines. Thus, the double-star induction machine is taken, as an example of multiphase machines, to introduce the principle of the study presented in this paper. In fact, the purpose of this paper is to maintain the PF of the power-winding, of the double star induction machine, in vicinity of unity whatever the drive operating point. Also, this control scheme can be generalized for several kinds of multiphase machines

Six-phase induction machine operating as a standalone self-excited induction generator

International audienceThis paper deals with the use of multiphase induction machines in renewable energy applications such as wind and hydropower. Thus, some preliminary test results carried out on a six-phase induction machine operating as a stand-alone self-excited induction generator and supplying various loads under different conditions are presented. Firstly, the dynamic model of the power generation system is developed considering the magnetizing inductance saturation and excitation capacitors sizing to ensure the excitation task. Then, simulation and experimental results carried out on a 5.5 kW six-phase squirrel-cage induction generator are presented and discussed

Circulating current reduction-based hybrid controller of an electrical drive system fed by two parallel inverters

International audienceThis paper presents a control technique of an electrical drivesystem fed by two parallel-connected voltage source inverters(VSIs). Two types of controllers are used to ensure a correctcontrol of the system under different situations, especially, incase of structural or control imbalances between the two VSIs,which leads to parasitic zero-sequence circulating currents (ZSCC)appearance. So, a linear PI controller and a nonlinear sliding modecontroller are combined together to act simultaneously based on thefrequency separation principle and form hybrid controller.Therefore, the designed controller allows reduced ZSCC and offersstability and robustness against external disturbances. Simulationand experimental investigations shown that the proposed hybridcontroller ensures the control of the drive system with ZSCCsuppression even in the presence of imbalances

Circulating current reduction-based hybrid controller of an electrical drive system fed by two parallel inverters

International audienceThis paper presents a control technique of an electrical drivesystem fed by two parallel-connected voltage source inverters(VSIs). Two types of controllers are used to ensure a correctcontrol of the system under different situations, especially, incase of structural or control imbalances between the two VSIs,which leads to parasitic zero-sequence circulating currents (ZSCC)appearance. So, a linear PI controller and a nonlinear sliding modecontroller are combined together to act simultaneously based on thefrequency separation principle and form hybrid controller.Therefore, the designed controller allows reduced ZSCC and offersstability and robustness against external disturbances. Simulationand experimental investigations shown that the proposed hybridcontroller ensures the control of the drive system with ZSCCsuppression even in the presence of imbalances

Energy Management and Optimal Control Strategies of Fuel cell/Supercapacitors Hybrid Vehicle

International audienceIn this paper, an energy management strategy (EMS) based on optimal control theory is applied to a hybrid vehicle propelled by fuel cell and supercapacitors pack. In order to show the effectiveness of this strategy, another EMS based on thermostat method is proposed and compared with the first one. Firstly, the power sources used in this study are presented with the electrical model of each one, and the hybrid architecture is given. Then, the EMS based on optimal control is expressed, where the minimization of the hydrogen consumption is its objective as well as the supercapacitor state of charge control. Then, the thermostat method strategy, which is a simple control method based on rules imposed by the limits of the power sources is applied. These two EMSs have been simulated using Matlab/Simulink. The results indicate the effectiveness of the energy management based on optimal control, which leads to improving the fuel consumption and a good control of the auxiliary source