Active band-type brake system for chemical polyester melt metering pump

Abstract

The invention discloses an active band-type brake system for a chemical polyester melt metering pump. The system is used for controlling a motor of the metering pump to quickly brake and carrying out band-type brake on the motor under the condition that the metering pump needs to be controlled to stop. The system comprises a controller, a three-phase bridge circuit, a group of relays, a group of three-phase contactors and a power supply. When the metering pump needs to be controlled to stop, the relays are controlled to disconnect the motor of the metering pump and a frequency converter, and the system is in a free mode; when the rotating speed is lower than a first threshold value, the system gets into a brake mode, and active short-circuit operation is performed on a three-phase winding of the motor, so that high-amplitude brake torque is generated, and rapid stopping of the motor is realized; and when the rotating speed is lower than a second threshold value, the system gets into a band-type brake mode, and the three-phase bridge circuit is used for introducing direct current into the motor to realize band-type brake, so that the autorotation of the metering pump caused by the inertia of melt is prevented, and production waste is avoided.

Description

technical field [0001] The invention relates to an active brake system for a metering pump, which belongs to the field of power electronics and power transmission. Background technique [0002] Since the 1980s, metering pumps have developed rapidly in terms of structure and control methods. As one of the most critical components in the spinning machine in the production of polyester filament in the chemical fiber industry, the function of the metering pump is to pressurize the melt entering the spinning machine and accurately meter it into the spinning assembly. The upper end of the metering pump is connected to the motor through the transmission device. At present, the inverter is mostly used to control the motor. Considering the cost problem, one inverter usually needs to control multiple metering pumps. When one or several metering pumps need to be shut down due to production or equipment failure, etc., the metering pumps to be shut down can only be cut off through hardw...

AI Technical Summary

Problems solved by technology

However, the rotating melt usually rotates with the metering pump due to inertia, resulting in problems such as melt pipes not being able to freeze or producing waste

The conventional solution is to prevent the self-rotation of the metering pump through a mechanical brake device. This method is not only inefficient but also has great potential safety hazards

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