How does a grid connected inverter work?
The grid connected inverter takes the direct current and, in simplified terms, runs it through a transformer. The inverter runs the DC through two or more transistors that are rapidly turned on and off and feeding two different sides of the transformer to convert DC into AC. The grid connected inverters require reference frequency to synchronize with the grid (e.g. 50 or 60 Hz) using a local oscillator and limit the voltage to no higher than the grid voltage. The power produced is fed into your house/ office electrical panel and provides power for all needs. The excess power automatically flows out to the grid, spinning meter backwards. Grid-tie inverters are also designed to quickly disconnect from the grid if the utility grid goes down to prevent the energy it transfers to the grid from harming any line workers who are fixing the line issues. This feature is known as Anti-Islanding. Read more
What are the points to keep in mind while selecting a grid connected inverter?
Things to check before finalizing the grid connected inverter for your system: Warranty: Compare the warranties offered with solar inverters. Most of the manufacturers offers 10 years of warranty with annual maintenance charges . Also, check whether the manufacturer offers onsite services, years of establishment, no. of inverters sold & response time in case of technical faults. Peak Efficiency This is the specific ratio of how much energy is consumed and how much energy is output. Like other appliances, a certain amount of energy is lost in the conversion of electricity from DC to AC. Most inverters operate at 95% & above efficiency, and therefore resulting in greater amounts of energy to the grid. Power Maximization (MPPT) MPPT stands for Maximum Power Point Tracker. Its function is to maximize the energy available from the connected solar module arrays at any time during its operation. The voltage at which PV module can produce maximum power is called ‘maximum power point’ (or peak power voltage). Maximum power varies with solar radiation, ambient temperature and solar cell temperature. The major function of MPPT is to extract the maximum available power from PV module by making them operate at the most efficient voltage. Data logger & Online monitoring Now-a-days inverters have data-logging feature enabling you to download information to a computer, or transmit it over Bluetooth or your Wi Fi network. With online monitoring you can check the real-time generation or periodic information about the performance of your system on your PC, smartphone etc. Read more