What is a soft starter? What is the difference between it and the inverter? -Solutions - Huaqiang Electronic Network

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Soft starters are advanced motor control devices that offer a range of functions including smooth start-up, gentle shutdown, energy saving during light load conditions, and multiple protection mechanisms. Known as "Soft Starters" internationally, they primarily consist of three-phase parallel thyristors connected in series between the power supply and the motor, along with an associated electronic control system. By adjusting the conduction angle of these thyristors, the input voltage to the motor can be controlled according to specific needs, enabling various operational functions. Unlike frequency converters, which are used for speed control by altering both voltage and frequency, soft starters function as voltage regulators. During motor startup, they only adjust the voltage without changing the frequency. While frequency converters can perform all the functions of a soft starter, they are significantly more expensive and have a much more complex design. This makes soft starters a more cost-effective and simpler solution for applications where speed control is not required, but smooth starting and stopping are essential.