Power Inverter DC to AC Basics

 Inverter Basics

        An inverter or converter is a device designed to convert direct current (DC) power into alternating current (AC) power. DC power only flows in one direction, while AC switches from negative to positive many times each second. Power plants produce 120 volt AC and send it into homes, so most appliances are designed to run on AC at this voltage. Batteries, however, produce DC electricity, and at a much lower voltage. In order to make this power usable, inverters change it to AC and increase the voltage.
    Making a Stair-Step Wave
        Inverters use electronic switches known as transistors to create the basic AC signal. Transistors are capable of taking a small signal and turning it into a much larger voltage. In an inverter, a computer sends electric signals to the transistors. First it turns on the positive transistors, creating the positive half of the wave. Then it turns them off and turns on the negative transistors, creating the negative half of the wave. Normal AC electricity flows in a sine wave, but inverters usually make stair-step waves. A stair-step wave is like a blocky approximation of a sine wave made out of several electric pulses from the transistors. For most applications, it is close enough.
    Upping the Voltage
        The current then runs through a step-up transformer, which increases the voltage to 120 volts. In a transformer, there are two electric coils placed next to each other. When AC current flows through one coil, it creates a moving magnetic field that permeates both coils. This field creates an electric current in the second coil. In a step-up transformer, the second coil has more to do wider than the first one is. This increases the voltage to 120 volts.