Abstract:A power inverter is a device that converts 220V power frequency AC power into a DC voltage with a regulated output. It needs to go through four steps ...
A power
inverter is a device that converts 220V power frequency AC power into a DC voltage with a regulated output. It needs to go through four steps of transformation, rectification, filtering, and voltage regulation. Every link has its role.
1. Rectifier filter circuit: The rectifier circuit converts the AC voltage Ui into a pulsating DC voltage, and then filters out the larger ripple components through the filter circuit, and outputs the DC voltage U1 with smaller ripple. The commonly used rectifier filter circuit has full-wave rectification. filter, bridge rectifier filter, etc.
2. Power transformer: step-down transformer, which converts the 220V AC voltage of the power grid into an AC voltage that meets the needs, and sends it to the rectifier circuit. The transformation ratio of the transformer is determined by the secondary voltage of the transformer.
3. Voltage stabilizer circuit: The function of the voltage stabilizer circuit is to stabilize the output DC voltage, which does not change with the change of the AC grid voltage and load. Commonly used integrated voltage regulators include fixed three-terminal voltage regulators and adjustable three-terminal voltage regulators.
4. Filter circuit: Most of the AC components in the output voltage of the rectifier circuit can be filtered out to obtain a relatively smooth DC voltage. Each filter capacitor C meets RL-C=3~5T/2 or the middle T is the input AC signal period, RL is the equivalent load resistance of the rectifier filter circuit.