An inverter generator is a power generator that can process raw power into a power feed similar to the power received through power lines. The generator part of an inverter generator is usually powered by gasoline or diesel fuel. "Inverter" means that the power is converted from direct current (DC) into alternating current (AC). Inverters are in direct contrast to rectifiers which turn AC power into DC power. Companies that manufacture inverter generator machines include Honda® and Cummins Onan®.
Both rectifiers and inverters are types of power converters, devices that change current from one type to another. Direct current is current that flows only one direction in a circuit. Batteries are charged using DC power. Alternating current is current that switches direction on a circuit. It is the type of current distributed to homes and businesses over power lines.
An example of a power inverter without a generator would be a device that plugs into a a car's cigarette lighter and outputs power through a standard electrical outlet. In this case, the inverter is changing the DC power from the car battery. The car battery can be drained of power while the car is not running, but it stays charged by the alternator while the car is being driven.
Advanced inverter generators condition power to provide a smooth flow for delicate electrical devices. Different models of inverter generators use different methods to condition the power feed to mimic power line power. Commonly, the AC power created by the generator is converted into DC power, rectifying the power, then it is changed back into conditioned AC power, inverting the power.
Inverter generators can be lightweight and portable, heavy-duty and somewhat portable, or they may be devices installed inside recreational vehicles (RV). Inverter generator machines are often preferred methods of generating power because they run more quietly and produce a more reliable power feed than traditional generators. A steady power feed is key when operating sensitive equipment like computers that can lose data or incur damage if power levels change too much. Inverter generator devices help protect powered machines from damage due to power surges or drop-outs.
In situations in which data can be lost by power changes, an inverter is necessary to ensure the safety and continued function of the powered hardware. For situations in which the power feed does not necessarily need to be conditioned for use, a generator without inverter capabilities can be used. Without an inverter, power surges and fluctuations can happen, so it is better to reserve generator-only power systems for emergency power situations.