Functions of a grid connected solar inverter
- Inversion: Converts DC electricity to AC electricityMaximum Power Point Tracking (MPPT): This function adjusts the voltage and current parameters coming from the solar modules to allow the maximum amount of power to be fed to the grid at any particular time.
- Grid Monitoring: The inverter constantly monitors the frequency and voltage of the grid and matches the power from the solar system to these parameters, enabling electricity to be fed on to the distribution network.
- Anti-Islanding Protection: The inverter monitors the grid to make sure it is operating within a certain frequency and voltage range. If the grid goes out side the normal frequency range, such as in a black out, then the inverter knows this and shuts off the solar power system. This protects utility workers repairing the network from being electrocuted. Once the grid is back within normal frequency and voltage ranges, the inverter detects this and resumes operation.
- Data Capture and Display: The inverter records the amount of power that is being produced by the solar power system at the current time, the daily energy production, and the energy produced over the life time of the inverter. This data is displayed on an LCD screen on the front of the inverter and some models allow this information to be uploaded to other devices such as laptop computers. This is how you assess the performance of your solar system.
The inverter is the most crucial piece of equipment in the solar power system. Only models from large well-known companies should be used who have offices in Australia. This ensures you have the best chance of having any warranty claims honored and a speedy replacement if anything happens to go wrong. Cheap models may not be as efficient in converting the DC electricity to AC electricity and may not be as weatherproof.