Experimental study of dependencies of dynamic characteristics of asynchronous electric drive of turbine mechanism on softstarter settings

The asynchronous electric drive has an increased starting current, which leads to a decrease in operational reliability of both the electric motor and the working machine due to a significant amplitude of the dynamic moment fluctuation. One way to improve the dynamic properties of asynchronous electric drives is to form transient characteristics by gradually increasing the voltage on the stator windings using soft starters. The initial voltage and its rise time to the nominal value are the main adjustment parameters of softstarters. To study the effect of softstarter adjustment parameters on the dynamic characteristics of the asynchronous electric drive of the turbine mechanism, experimental studies were carried out on a physical model, using which transient characteristics of current, rotation frequency and dynamic moment were obtained at various values of the initial voltage and capacitance of the capacitor, which sets the dynamics of voltage increase. It was revealed that the softstarter with rational adjustment allows to effectively reduce mechanical overloads in the electric drive. At the same time, the starting current decreases slightly, the start time increases. The use of only current and acceleration characteristics to evaluate the "smoothness" of the transition process is impractical, since they do not have a pronounced connection with the characteristic of the dynamic moment. Therefore, the most accurate method of setting the softstarter is to find rational values of the adjustment parameters by measuring the amplitude of the dynamic moment fluctuation.