Since the inverter power supply is responsible for the conversion between DC and AC in the circuit, its safety is particularly important. If a short circuit occurs in the inverter power supply, it may burn out. If you want to effectively avoid the occurrence of short circuit, you must pay full attention to the overcurrent short-circuit protection circuit in the inverter power supply. This article will introduce you to the design of overcurrent short circuit protection circuit.
Most of the loads in real life are impact loads, such as incandescent light bulbs. The resistance when cold is much lower than when it is lit. For rectifier loads such as computers and televisions, since the input alternating current needs to be rectified, a A relatively large capacitor is used for filtering, so the inrush current is relatively large. There are also inductive loads on motors such as refrigerators. The motor also needs electricity to generate relatively large torque from standstill to normal rotation, so the starting current is also relatively large.
If our inverter can only be set to a rated output power that can work for a long time, the load with a starting power greater than this rated output power will not be able to start, so it is necessary to equip the inverter according to the starting power. This is obviously It's a waste. In practice, when we design an overcurrent short-circuit protection circuit, we will design two protection points, rated power and peak power. Generally, the peak power is set to 2-3 times the rated power. In terms of time, the rated power will not be protected after working for a long time, and the peak power will generally only last for a few seconds before being protected.