In Rwanda, agricultural industry depends on seasonal rain, and this has been a great challenge to agriculture in Rwanda. The designed sample of Photovoltaic pumping system is for irrigation on a piece of land, with 10...In Rwanda, agricultural industry depends on seasonal rain, and this has been a great challenge to agriculture in Rwanda. The designed sample of Photovoltaic pumping system is for irrigation on a piece of land, with 100 m2 field fed by underground water tank of 8 meters of elevation collected during rainy seasons. The adapted 100 m2 field is based on the fact that Rwanda is a densely populated country, also is adapted to be used especially in horticulture to increase exportation. In this system, a photovoltaic system is used as a power source;a pump is coupled with electric motor to drive it and hosepipe to convey water to the storage tank. A sensor is used to send a signal to the driver section at the same time sending a signal to the microcontroller that controls the driver unit and the corresponding relay, which switches off the motor when the water level reaches the lowest level.展开更多
This paper focuses on modeling and perfor- mance predetermination of a photovoltaic （PV） system with a boost converter fed permanent magnet direct current （PMDC） motor-centrifugal pump load, taking the con- verter...This paper focuses on modeling and perfor- mance predetermination of a photovoltaic （PV） system with a boost converter fed permanent magnet direct current （PMDC） motor-centrifugal pump load, taking the con- verter losses into account. Sizing is done based on the maximum power generated by the PV array at the average irradiation. Hence optimum sizing of the PV array for the given irradiation at the geographical location of interest is obtained using the predetermined values. The analysis presented here involves systems employing maximum power point tracking （MPPT） as they are more efficient than directly coupled systems. However, the voltage and power of the motor might rise above rated values for irradiations greater than the average when employing MPPT, hence a control scheme has been proposed to protect the PMDC motor from being damaged during these conditions. This control scheme appropriately chooses the optimum operating point of the system, ensuring long-term sustained operation. The numerical simulation of the system is performed in Matlab/Simulink and is validated with experimental results obtained from a 180 V, 0.5 hp PMDC motor coupled to a centrifugal pump. The operation of the system with the proposed control scheme is verified by varying the irradiation levels and the relevant results are presented.展开更多
文摘In Rwanda, agricultural industry depends on seasonal rain, and this has been a great challenge to agriculture in Rwanda. The designed sample of Photovoltaic pumping system is for irrigation on a piece of land, with 100 m2 field fed by underground water tank of 8 meters of elevation collected during rainy seasons. The adapted 100 m2 field is based on the fact that Rwanda is a densely populated country, also is adapted to be used especially in horticulture to increase exportation. In this system, a photovoltaic system is used as a power source;a pump is coupled with electric motor to drive it and hosepipe to convey water to the storage tank. A sensor is used to send a signal to the driver section at the same time sending a signal to the microcontroller that controls the driver unit and the corresponding relay, which switches off the motor when the water level reaches the lowest level.
文摘This paper focuses on modeling and perfor- mance predetermination of a photovoltaic （PV） system with a boost converter fed permanent magnet direct current （PMDC） motor-centrifugal pump load, taking the con- verter losses into account. Sizing is done based on the maximum power generated by the PV array at the average irradiation. Hence optimum sizing of the PV array for the given irradiation at the geographical location of interest is obtained using the predetermined values. The analysis presented here involves systems employing maximum power point tracking （MPPT） as they are more efficient than directly coupled systems. However, the voltage and power of the motor might rise above rated values for irradiations greater than the average when employing MPPT, hence a control scheme has been proposed to protect the PMDC motor from being damaged during these conditions. This control scheme appropriately chooses the optimum operating point of the system, ensuring long-term sustained operation. The numerical simulation of the system is performed in Matlab/Simulink and is validated with experimental results obtained from a 180 V, 0.5 hp PMDC motor coupled to a centrifugal pump. The operation of the system with the proposed control scheme is verified by varying the irradiation levels and the relevant results are presented.
