The simplicity of photovoltaic motors makes them ideal candidates for fully autonomous applications requiring thousands of operating hours without maintenance, like water pumping. Photovoltaic motors use photovoltaic cells optically commutated by a shutter driven by the motor rotor to convert light energy into mechanical energy, without the need of any brushes or other power electronics. With the decrease of photovoltaic cells price, photovoltaic motors could be more affordable and reliable than conventional systems, and therefore particularly well suited for off-grid applications. The concept has been patented under various forms, but the scientific literature is so far very scarce. In this article, we attempt to classify photovoltaic motors, and to explain in details their physical working principle. Then we compare the different architectures by defining two pre-design factors linked to the system maximal output power. Finally, we report first experimental results on a photovoltaic switched reluctance motor (PV SRM) prototype using a 6/4 switched reluctance machine and 12 photovoltaic cells.

A photovoltaic switched reluctance motor converts light energy into mechanical energy, without power electronics, brushes or magnets. With the rapid decrease of photovoltaic cells price, its simplicity makes it ideal for low cost, autonomous and reliable applications, such as water pumping in isolated areas with good solar irradiation. But the concept does not allow for motion control or variable-speed operation. In order to evaluate its range of application, then to optimize its sizing, we need to understand the complex interactions between the photovoltaic cells and the motor. To this end, we develop here a numerical model of our photovoltaic switched reluctance motor prototype. It takes into account the nonlinearity of photovoltaic cells and of the switched reluctance machine. Despite the uncommon operation of the photovoltaic cells, the agreement between the simulation and the measures is so far good, thus validating our modeling strategy.

Abstract-A solar-powered switch reluctance motor drive using photovoltaic transistors is presented. The expression "photovoltaic transistor (PVT)" is used to designate a conventional photovoltaic cell used as a light-controlled power transistor. To obtain a motor drive, a set of PVTs controls the current fed from an external DC power source to the motor phases. The control is achieved by modulating the sunlight hitting the PVTs using a shutter driven by the motor rotor. If the external DC source is a solar panel, the resulting system is able to convert light energy into mechanical energy, without the need of any brushes or other power electronics components. This system could be more affordable and reliable than conventional ones, and therefore is well suited for off-grid applications like water pumping. This article first discusses the operation of a photovoltaic transistor through the proposition and the validation of a model. Then, the operating principle of a PVT inverter is clarified. Finally, experimental and numerical results on the first PVT inverter-fed switched reluctance motor are reported. A prototype was built using a switched reluctance motor 6/4 and 12 PVTs. It was here connected to an external 12 V DC power source as a step before using a solar photovoltaic source. Results showed that the PVT inverter-fed switched reluctance motor was operating as expected and provided useful power.

Abstract-A solar-powered switch reluctance motor drive using photovoltaic transistors is presented. The expression "photovoltaic transistor (PVT)" is used to designate a conventional photovoltaic cell used as a light-controlled power transistor. To obtain a motor drive, a set of PVTs controls the current fed from an external DC power source to the motor phases. The control is achieved by modulating the sunlight hitting the PVTs using a shutter driven by the motor rotor. If the external DC source is a solar panel, the resulting system is able to convert light energy into mechanical energy, without the need of any brushes or other power electronics components. This system could be more affordable and reliable than conventional ones, and therefore is well suited for off-grid applications like water pumping. This article first discusses the operation of a photovoltaic transistor through the proposition and the validation of a model. Then, the operating principle of a PVT inverter is clarified. Finally, experimental and numerical results on the first PVT inverter-fed switched reluctance motor are reported. A prototype was built using a switched reluctance motor 6/4 and 12 PVTs. It was here connected to an external 12 V DC power source as a step before using a solar photovoltaic source. Results showed that the PVT inverter-fed switched reluctance motor was operating as expected and provided useful power.

This paper presents an original and autonomous solar pumping system, based on a Switched Reluctance Motor commutated by photovoltaic cells (SRMPV) and powered by a photovoltaic generator. In this work, experimental tests characterizing the SRMPV are presented. Based on these experiments, the first mathematical model of this complex system is developed and implemented under the Matlab-Simulink platform. In order to optimize the design of the SRMPV, the simulation platform is used to perform a sensitivity study. This research will focus on the determination of the optimal number of coils, the optimal air gap, and the optimal winding cross area of the switched reluctance motor.