General ways of cost reduction in solar power generation are Solar Tracked Photovoltaic (PV) arrays and concentrator systems. The PV array tracking becomes infeasible with increase in the size of the array and concentrated system is ineffective for continuous power generation as it requires external cooling system. Proposed approach here is to employ a novel auxiliary mirror drive mechanism to track the sun and reflect the rays on to stationary PV arrays. The performance is compared with same PV module without reflector under the same environmental conditions. Solarex SX 38 PV module and cleardome solar reflector (96% reflectivity) are used for the experiments. PV module is connected to electrical load through Maximum Power Point Tracker (MPPT) and data acquisition system for voltage and current measurements. Incident radiation is measured using Li-Cor pyranometers located on the plane of the module and horizontal plane. A shadow band device is used for the measurement of diffuse solar radiation. The PV module is placed facing south at a tilt angle equal to the latitude angle. A reflector is placed facing north and oriented using the novel Mirror Positioning Device (MPD). The MPD is a five bar spherical mechanism used for solar tracking. This mechanism has two degrees of freedom which allows for tracking the sun along its azimuth and altitude. The mechanism is driven by two servo motors which actuate two links. The actuated link 1 helps in achieving the altitude gained by the sun while the actuated link 2 helps to attain the azimuth (or horizontal movement). The reason for using a spherical mechanism is due to the virtue of its architecture; it allows for carrying a larger payload and also helps in reducing weight. Its advantages are that it requires less power than traditional PV array tracking; there is no need for sensors to determine the position of the sun and also that it being a two degree of freedom spherical mechanism yields a large singularity free mirror orienting workspace. Solar radiation, efficiency, and temperature are plotted as a function of time for analysis. Average diffuse solar radiation is found to be in the range of 15 to 20% of total solar radiation. Different experiments are performed to find out the optimum cycle speed for reflector. Measurements show that output from the PV panel can be increased in the order of 22% with the use of tracking reflector. This work has succeeded in its goal in realization that the considerable increase in output power from PV modules can be achieved.

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