Miscellaneous

Typical applications for power inverters include:

Portable consumer devices that allow the user to connect a battery, or set of batteries, to the device to produce AC power to run various electrical items such as lights, televisions, kitchen appliances, and power tools.

Use in power generation systems such as electric utility companies or solar generating systems to convert DC power to AC power.

Use within any larger electronic system where an engineering need exists for deriving an AC source from a DC source.

Frequency conversion - if a user in (say) a 50 Hz country needs a 60 Hz supply to power equipment that is frequency-specific, such as a small motor or some electronics, it is possible to convert the frequency by running an inverter with a 60 Hz output from a DC source such as a 12V power supply running from the 50 Hz mains.

In refrigeration compressors

An inverter can be used to control the speed of the compressor motor to drive variable refrigerant flow in a refrigeration or air conditioning system to regulate system performance. Such installations are known as inverter compressors. Traditional methods of refrigeration regulation use single-speed compressors switched on and off periodically; inverter-equipped systems have a variable-frequency drive that control the speed of the motor and thus the compressor and cooling output. The variable-frequency AC from the inverter drives a brushless or induction motor, the speed of which is proportional to the frequency of the AC it is fed, so the compressor can be run at variable speeds—eliminating compressor stop-start cycles increases efficiency. A microcontroller typically monitors the temperature in the space to be cooled, and adjusts the speed of the compressor to maintain the desired temperature. The additional electronics and system hardware add cost to the equipment, but can result in substantial savings in operating costs. The first inverter air conditioners were released by Toshiba in 1981, in Japan.

Power grid

Grid-tied inverters are designed to feed into the electric power distribution system.[14] They transfer synchronously with the line and have as little harmonic content as possible. They also need a means of detecting the presence of utility power for safety reasons, so as not to continue to dangerously feed power to the grid during a power outage.

Synchronverters are inverters that are designed to simulate a rotating generator, and can be used to help stabilize grids. They can be designed to react faster than normal generators to changes in grid frequency, and can give conventional generators a chance to respond to very sudden changes in demand or production.

Large inverters, rated at several hundred megawatts, are used to deliver power from high voltage direct current transmission systems to alternating current distribution systems.