Cause of high current of Roots blower and how to realize high efficiency

The frequency converter of Roots blower shall be selected according to the constant torque load. For the 45kW Roots blower, the rated current of the motor is 84.5A, and the ACS604-0100-375kW frequency converter is selected. Under the general application load, the power of the motor is allowed to reach 7500kW; Under heavy load conditions, the power can reach 55kW, and the output current can reach 168A in one minute within a 10 minute period, which is twice the output current of the motor. In a 15 second period, the output current can reach 224A in two seconds, which is 2.65 times the rated current of the motor, which can meet the requirements of transient overload.
According to different typical industrial objects, many different kinds of application macros are designed. The so-called application macros are preprogrammed parameter sets. Using the application macro can quickly and simply complete the startup of AC600. The application macro reduces the number of parameters that need to be set during the startup process. All parameters have the default values set at the factory. Therefore, the user should determine which application macro to use before debugging the inverter. Once the macro is selected, the user can check, define For frequency converter test selection and adjustment, since there are English prompts in the menu, the physical meaning of each parameter is intuitive and clear, and users can select conveniently.
    

The conventional parameters to be determined during commissioning include start/stop/direction signal, relay output signal, analog I/O signal and range calibration, acceleration and deceleration time, motor locked rotor protection, overload protection, soft limit of various electric quantity operation, various faults, alarm conditions, etc. In addition, Xinqian Shun Fan knows that there are two important parameters to choose:
First, the startup function should be selected, which can enable the frequency conversion system to smoothly pass the transient low voltage of the power supply or even the transient power loss, and automatically start after the power supply voltage returns to normal, which is very necessary for such important loads as gas supply;
Second, the inverter DC bus over-voltage automatic control and undervoltage automatic control are set to use, so that the regenerative current can be automatically limited when the motor is fast braking, so that the DC bus will not be over-voltage. When the power supply is low, the motor can automatically enter the regenerative power generation state to ensure that the DC bus voltage is not lower than the low voltage limit, This automatic control of bus voltage is of great significance for protecting the normal operation of frequency conversion system and reducing alarm and shutdown faults.