Updated: Dec 26, 2019
A power inverter or inverter is an electronic appliance that converts DC (direct current) electricity from sources such as batteries or solar cells to AC (alternate current) electricity for use in appliances.
The Uses of Transformers In Inverters
Solar cells generate direct current from sunlight in the regions of 12V, 24V, 48V, 72V or 96V. As do batteries. A transformer inside the inverter is used to step up the generated voltage to the 220V required for use in appliances. A transformer is used to step-up or step-down the generated voltage while the inverter is used to convert it from DC to AC.
A transformerless inverter by definition, is an inverter which does not have a transformer. Since the function of stepping up the voltage is necessary, transformerless inverters do not dispense with this function, rather the function is carried out in an entirely different manner.
What then Is the Difference Between Conventional Inverters and Transformerless inverters?
The major difference is that the transformer is replaced with a computerized multi-step process and other electronic components. These components play the role of the transformer.
A transformerless inverter will be described as 'TL' by its manufacturers. Most, if not all of Growatt inverters are transformerless inverters.
The Advantages of Transformerless Inverters Over Conventional Inverters
Transformerless inverters are generally more efficient than conventional inverters because because they are able to avoid internal energy losses and extra component costs.
Due to the absence of a transformer, transformerless inverters are light, compact, and relatively cheaper than conventional inverters.
Since transformerless inverters use electronic switching rather than mechanical switching, the amount of heat and buzzes produced by standard inverters is greatly reduced. This, in some cases, removes the need for cooling fans.
Traditional inverters work through only one power point, which means panels that are performing at lower frequencies will lower DC output for the entire system. But with transformerless inverters, solar panels can be installed in two different directions (i.e. north and west) on the same rooftop and generate DC output at separate peak hours with optimal effects.
The Disadvantages Of Transformerless Inverters
In a conventional inverter the DC and AC circuits are isolated, this is not so in transformerless inverters. Even though in some transformerless inverters, the current passes through a capacitor, the capacitor may not always be as reliable as an actual transformer. In other words, transformerless inverters are less complex in their designs and thus more prone to surges and shocks. This raises safety concerns especially in Nigeria where residential connections are mostly not grounded with the use of lightning rods. However, this can be solved with the use of stronger installation wires. Also, a TL inverter will most likely have to be earthed.