Power Inverters

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Automotive Power Inverter
Automotive Power Inverter

A power inverter is an electrical device,which converts the direct current (DC), which the vehicle uses for power, to alternating current (AC). The converted AC can be at any required voltage and frequency, with the use of appropriate transformers, switching, and control circuits.

In one simple power inverter circuit, DC power is connected to a transformer through the center tap of the primary winding. A switch is rapidly switched back and forth to allow current to flow back to the DC source following two alternate paths through one end of the primary winding and then the other. The alternation of the direction of current in the primary winding of the transformer produces alternating current (AC) in the secondary circuit. The electromechanical version of the switching device includes two stationary contacts and a spring supported moving contact. The spring holds the movable contact against one of the stationary contacts and an electromagnet pulls the movable contact to the opposite stationary contact. The current in the electromagnet is interrupted by the action of the switch so that the switch continually switches rapidly back and forth. This type of electromechanical inverter switch, called a vibrator or buzzer, was once used in vacuum tube automobile radios.

As they became available with adequate power ratings, transistors and various other types of semiconductor switches have been incorporated into inverter circuit designs. Basically now a days it’s a practice to use thyristors (SCR's). A thyristor is a solid-state semiconductor device with four layers of alternating types of materials. They act as switches, conducting when their gate receives a current trigger, and continue to conduct while they are forward biased (that is, while the voltage across the device is not reversed). SCR's are incorporated for better and efficient switching and their variable firing range which make them adequate for usage.

The most common types of power inverters are modified sine wave power inverters, and pure sine wave power inverters. Modified sine wave inverters are the most common and least expensive power inverters. In most cases, a modified sine wave inverter will work fine, powering fans, electronic devices with power adapters and small appliances without problems. However, high-end devices plugged directly into one of these power inverters may run loud or hot, or may have some electronic distortion. Pure sine wave inverters are the high-power type, outputting clean power on par with standard utility electricity. These inverters are great for devices that draw a lot of power. These more expensive power inverters will work with sensitive electronic equipment with no problem.

Who Makes This


Rally Mfg

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