The basic principle of soft starting is to control the motor's starting current, allowing the motor to gradually accelerate during the starting process. Specifically, a soft starter regulates the motor's input voltage during startup, causing the starting current to gradually increase until it reaches the rated current. During this process, the motor speed also gradually increases until it reaches the rated speed.
The working principle of a soft starter can be divided into the following steps:
Startup preparation: Before the motor starts, the soft starter performs a series of checks and preparations, including checking the motor's status and setting startup parameters.
Voltage regulation: During motor startup, the soft starter gradually increases the motor's input voltage according to the preset startup parameters. During this process, the motor's starting current also gradually increases.
Current control: During the motor startup process, the soft starter continuously monitors the motor current to ensure that the current remains within the preset range. If the current exceeds the preset value, the soft starter reduces the input voltage to bring the current back within the preset range.
Acceleration control: During the motor startup process, the soft starter adjusts the input voltage in real time based on the motor speed and current, allowing the motor to gradually accelerate until it reaches the rated speed.
Startup completion: Once the motor reaches the rated speed, the soft starter adjusts the input voltage to the rated value, completing the startup process.