An important part of a photovoltaic solar system is the device called a solar inverter, below I will explain How does a solar inverter work?
How does a solar inverter work?
In this post we are going to talk about a fundamental element in any photovoltaic solar installation, whether for self-consumption or isolated from the network. At the end of the post you will know what a solar inverter is and how it works.
Much has been written about the advantages of photovltaic energy and it is important that we know the fundamental technical elements of any photovoltaic installation. This way you will make your investment decision with the best possible information.
Whether you want TO SELL SOLAR ENERGY TO THE distribution network of your home or if you want to consume your own electricity, you will need to install some more equipment in addition to photovoltaic solar panels. Among the essential equipment are photovoltaic inverters.
What is the photovoltaic solar inverter for?
The electrical current generated by photovoltaic panels is not the current we normally use at home or the one that circulates through the electrical distribution network. Photovoltaic panels produce direct current, while most of our appliances and lights use alternating current. The photovoltaic inverter transforms direct current into alternating current so that we can use it at home or so that it can be injected into the electrical network if our purpose is to sell energy.
How does a photovoltaic solar inverter work?
The photovoltaic inverter has the function of converting the direct current, which is produced by the solar panels, into alternating current, which we can use. This transformation is achieved by means of power electronic devices (transistors, thyristors, coils, capacitors, etc.) that manage to transform a linear current into a sinusoidal current in the same way as the one we use in our homes and businesses.
This process generates heat , which must be dissipated for the transformation process to be efficient. That is why photovoltaic inverters have the need to dissipate heat , which is why some have built-in fans and others dissipate heat by convection.
Main functions of the photovoltaic inverter
The photovoltaic inverter fulfills the following functions in a photovoltaic solar installation.
- Convert continuous electrical energy into alternating energy, which is the most demanded in any home or industry. Without the inverter we would have to use DC/AC TRANSFORMERS in almost all of our electrical equipment.
- Improvement of the electrical current. The inverter also manages to stabilize the electrical waves, providing a quality and constant supply to prevent our appliances from suffering.
- Monitoring and control team. The inverter is the equipment that monitors the operation of our photovoltaic installation. This lets us know if something is not working properly. It also warns against any problem. The inverter can be remotely monitored with the appropriate remote control elements.
Different types of solar inverters
Below we explain what are the different types of solar inverters that you can find on the market. Each of which has its advantages and disadvantages, and is more recommended for one type of installation or another.
String or chain inverters
Small solar power installations use this type of inverter. The solar panels are connected in series with each other, and all the energy they generate is sent to the same inverter. This inverter is normally installed inside the house , and is responsible for transforming the continuous energy produced by the solar panels into the alternating energy that is used in any home.
String inverters are inexpensive and easy to maintain, as they are installed in an easily accessible location. Against them we have to mention that they can suffer from the so-called “bottleneck” effect: it will produce as much energy as the solar panel that produces the least energy, which can be inefficient if we have a panel with shaded areas or one that shows deterioration.
If you don’t want to spend a lot of money or all solar panels have the same performance, this type of inverter may be right for you.
With a string inverter we have a single piece of equipment that produces all the current inversion of the panels that are connected to it. On the contrary, when we opt for a microinverter system, each board has its own current inverter. Each solar panel has a microinverter that is also installed on the roof.
Microinverters are more efficient than string inverters, but they are also more expensive and more difficult to maintain, since in the event of a breakdown, we will have to go on deck to repair them.
These teams also have in their favor that they allow each panel to be monitored individually , so we can make comparisons and limit any possible problem more easily.
The power optimizers are also located on the cover , either installed after the board or integrated into it. Power optimizers send all energy to a single central inverter.
The power optimizer does not convert direct current to alternating current by itself, but relies on the inverter to do so. The power optimizer regulates the output voltage of the current so that all the plates have the same output voltage and the inverter can make better use of all the energy it receives.
With this type of installation we achieve higher energy performance, but we need to spend more money on assembly . The maintenance of the installation will also be more expensive and complex.
Photovoltaic technology is constantly evolving. There are different types of configuration in addition to a wide range of manufacturers. When making an assembly it is necessary that we know the basic elements of any photovoltaic installation and that we allow ourselves to be advised by specialists in the field.
A bad choice of equipment or the type of installation that we want to do can bring us great headaches in the long run. Depending on the objective that we pursue —electricity self-consumption or self-consumption and sale of surpluses to the distribution company— we will have to make an appropriate type of installation. We hope we have clarified your doubts about how a photovoltaic solar inverter works. Do not hesitate to contact us.