Advanced Inverters: A Step Forward

The 21st century is an age of imagination and innovation. Old and archaic inventions are now seeing radical overhauls in order to stay relevant. Almost everything that we use and see today is version 2.0 of the original product. This fast-paced and ever-evolving world demands change.

A widely used device in today’s world is the inverter, a simple appliance that converts Direct Current (DC) to Alternating Current (AC) and vice versa. It is a relatively old invention, dating back some 100 odd years. The older cruder designs were very inefficient and had a wide variety of limitations.     The basic designs consisted of a switch which is used to allow current to flow back to the DC source, following two alternate paths on one end of a primary transformer winding. This alternation of the current is what produces AC in the secondary circuit. The older designs used buzzers which caused a lot of vibrations. With time as transistors and various types of semiconductor switches became available, it was gradually incorporated. The problem arises when it produces a square wave due to the switch, instead of sinusoidal waves as produced by AC. Hence square wave inverters can only be sued for common household and commercial business.

Recent advancements have led to many different power circuit topologies and control strategies in inverter design. These help in solving the many issues that may be important in the way an inverter is used. Sometimes some equipment requires a specific waveform, in order to meet the requirements various devices like rectifiers and capacitors are used. And if the power supplied is to be at a fixed frequency, a resonator is utilised.

For very specific and high demand usage such as variable-frequency drive and high power applications like HVDC power transmissions, a certain type of inverter is used called a three-phase inverter. It basically consists of three inverter switches connected to three load terminals, which gives it a six-step waveform; this gives it zero voltage step between the positive and negative sections of the square wave. To get an inverter with a higher rating, two six-step three-phase inverters can be connected in parallel. This gives a 12-step form, and it can also be an 18-step waveform, with the help of three-inverters.

The sizes of inverters are of great concern; compared to any other household appliances they are very big. Some UPS inverters even outweigh entire computers. This bulk and size is very unnecessary and leads to problems. A lot of research is being put into reducing this size, and various competitions take place worldwide to help find a feasible solution. Recently, using 3D printers’, scientists have developed an inverter that can make electric cars lighter, more efficient and more powerful.

India is a fast and developing country with a lot of power needs. A majority of the areas, however, do not have access to electricity and have to rely on batteries and inverters. Luckily almost everyone has access to a mobile phone, and one can easily purchase the best inverter online at the tap of a button.