Engineering Solutions
Solar Photovoltaic power generator consists of solar modules in series and parallel connections, these convert solar radiations into DC electrical power at the pre-determined range of Voltages whenever sufficient solar radiation is available. The individual crystalline solar cells are connected together in a module (in series connection), which are hermetically sealed to survive in rugged weather conditions and ensures optimum performance during its long life.
In order to achieve a higher system voltage, modules are installed in a row arrangement, called a string. A higher system voltage has the advantage of lesser installation work, higher efficiency of the entire plant and usage of smaller cross section cables. Calculated no. of strings is connected in parallel by cables in Junction Boxes. Outputs from many such junction boxes are connected in parallel in the Main Combiner Box (MCB). This Main Combiner Box output is fed to the central inverters/Power Control Unit (PCU) to invert solar generated DC power in to conventional 3 phase AC power. AC power from inverters will be fed to LV panel.
Solar panels mounted in the field generate DC electric power. The DC electric power generated by the solar panels cannot be fed directly in to the utility grid. The inverters invert the direct current output from the solar array into grid compliant AC voltage, feeds it in to the utility grid system with proper protection and control.
The grid connected inverter (GCI) range of inverters comes with built-in transformer that ensures galvanic isolation of the DC side from the AC network. This is an important requirement for many utilities to permit connection of solar panels on to the grid. The system automatically starts up in the morning and begins to export power to the grid, provided there is sufficient solar energy and the grid voltage, frequency is within the range. If the grid goes out of range the inverter will be immediately disconnected and reconnected automatically at a pre-determined time after the grid comes back within range.
Monitoring systems is mainly used to monitor the performance of the Inverters, energy yield, temperature, irradiance level etc. It provides an extremely flexible interface to facilitate PC-based inverter monitoring via modem, GSM, Ethernet, or Internet connections.