Switching power supplies are categorized into AC-DC power supplies, DC-DC converters, and DC-AC inverters. They convert the input of commercial or DC power supplies into specified voltages or currents and are employed in almost all electronic devices or systems that require a stable DC power supply.

A contactor is an electrically-controlled switch used for switching an electrical power circuit.
A contactor is typically controlled by a circuit which has a much lower power level than the switched circuit, such as a 24-volt coil electromagnet controlling a 230-volt motor switch.

a. Damping of inrush current in low voltage PFC systems
b. For PFC systems with and without reactors

Thyristor modules are very effective in eliminating the inrush current of capacitors.
They have controlled switching devices that can be made to switch on when the voltage across the thyristor is zero, thereby eliminating the inrush current. Additionally, thyristor switching is used when the load variation is rapid as in the case of cranes, lifts, spot welding, plastic extrusion etc.

a. Main supply networks with high load fluctuations for dynamic PFC systems
b. Presses
c. Welding machines
d. Elevators
e. Cranes
f. Wind turbines