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This paper presents a dual parallel connected PMSM fed by a single power inverter. Both motors have to respect the synchronism even if they have different load torque. The rotor position of the two motors i.e. the load applied on each motor are consequently permanently compared. The motor with the highest load is set as the master one and is autopiloted. The other one which has the same applied voltage has the same electric pulsation and so the same speed rotation. The change of the master choice is done whereas the load applied on the machine is changing so that oscillations appear during this change. The steady state is however rapidly attained and the synchronism stays always observed.

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. Abstract This paper presents a new and original Mono inverter Multi parallel PermanentMagnet Synchronous Motor (PMSM) system. To obtain the stability of such a system, each of the motor synchronisms should always be respected regardless of their load torque. In this case, only one motor, called "master motor", will be self-piloted. If the chosen master motor is the one with the highest applied load torque, synchronism is respected for each of the motors. To find this machine, a solution which compares the rotor positions is thus developed.Experimental results are given for a system with 2 PMSM plugged in parallel.The proposed solution can however be applied to systems whatever the motor numbers, therefore additional simulations are provided for a 4 PMSM system.

High speed permanent magnet synchronous motors (PMSMs) are used in electric vehicles because of their intense power density. The high speed implies a significant electromotive force and requires flux weakening. The usual control algorithms realize flux weakening by adding a negative I d current component when the voltage required by the current regulation exceeds the maximum voltage depending on the battery. If the magnet can be totally defluxed, then it is better to use a maximum torque per volt strategy. Furthermore, there is no speed regulation in the control and the driver gives a torque reference. This reference value has to be limited by the attainable operating points; therefore, the battery power limit has to be taken into account in addition to the voltage and current limits. The d-q current references are calculated to minimize the total current magnitude required to reach the reference torque. This paper proposes a strategy to control a PMSM operating continuously since the speed zero up to the maximum speed without the switching algorithm, in order to take into account the different limitations (current, voltage, and power) and to expand the overspeed zone. In order to validate the proposed strategy, experimental results are shown for a low power machine.Index Terms-Flux weakening, high speed permanent magnet synchronous motor (PMSM), maximum torque per volt (MTPV), torque-speed characteristic, vector control. NOMENCLATURE LPFLow-pass filter. MinCPT Minimal current per torque. MTPAMaximum torque per ampere.

This paper presents novel bi-converter structure to supply the Doubly Fed Induction Machine (DFIM). Two Voltage Source Inverters (VSI) feed the stator and rotor windings. The outputs of two VSI are combined electro-mechanically in the machine and, as a result, novel features can be obtained. For example, for high power drive applications, this configuration use two inverters dimensioned for a half of the DFIM power. A new Dual-Direct Torque Control scheme is developed with flux model of DFIM. Two Switching Tables (ST) linked to VSI are defined for stator and rotor flux vector control. Experimental and simulation results confirm good dynamic behaviour in the four quadrants of the speed-torque plane. Moreover, experimental results show the correct flux vector control behaviour and speed tracking performances.

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In many developing countries, the lack of electricity in rural areas is still a key issue for millions of people. The reuse of discarded components in renewable energy systems, based on the frugal innovation concept, has been identified as a solution for rural electrification in countries where renewable resource is plentiful. Specific emphasis is paid in this work to the application of reuse from an engineering viewpoint for a Renewable Energy System, including a "solar" element, composed of solar Photovoltaic (PV) panels and of modified Power Supply Units (PSUs), a "hydro" part and an energy storage system with used car batteries. The scientific objective of this work is to evaluate the environmental impact of this solution, considering only the solar element, as compared to a conventional system consisting of photovoltaic panels, lead-acid batteries, a charge controller and an inverter for small village consumption. For this purpose, Life Cycle Assessment (LCA) has been selected as a methodological framework and both solutions have been described and sized. The results have shown that in the reuse scenario, the impact of PSUs, Uninterruptable Power Supply Units (UPSs) and a microcontroller kit remains very low (0.12% of total impact) while PV modules contribute significantly (66% of total impact). Nevertheless, the consequences of reusing lead-acid batteries are still significant due to the combination of several effects: their weight, reduced efficiency and the need for frequent replacement. A 40% reduction of the environmental burden obtained by the reuse solution is clearly due to the absence of battery production impacts in the case of reuse. A sensitivity analysis has been performed to determine the impact of parameters such as component efficiency, lifetime and transportation distance on environmental impacts. The efficiency of repurposed PSUs and UPSs is the most significant parameter on the environmental impact categories in the reuse solution.

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