Novel double-motor mixing head control system and method for KR molten iron desulfuration

Abstract

The invention provides a novel double-motor mixing head control system and method for KR molten iron desulfuration. The double-motor mixing head control system comprises a PLC (Programmable Logic Controller), a mixing motor No.1 and a corresponding frequency converter No.1, a mixing motor No.2 and a corresponding frequency converter No.2, wherein the mixing motor No.1 and the mixing motor No.2 are rigidly connected by a gearbox; a speed closed-loop PID (Proportion Integration Differentiation) controller and a torque filter are arranged in the PLC; the output end of the speed closed-ring PID controller is connected with the input end of the torque filter; the output end of the torque filter is connected with the input ends of the frequency converter No.1 and the frequency converter No.2, respectively; the frequency converter No.1 and the frequency converter No.2 are torque control type frequency converters; the output end of the frequency converter No.1 and the output end of the frequency converter No.2 are connected with the input end of the mixing motor No.1 and the input end of the mixing motor No.2, respectively; and the practical speed value of the motor No.1 at the output end of the mixing motor No.1 is fed back to the input end of the speed closed-ring PID controller. The double-motor mixing head control system has the beneficial effects of eliminating the synchronization time difference of the two motors and being high in synchronism; moreover, the production and maintenance are convenient, the debugging is simpler and the application range is wider.

Description

technical field [0001] The invention relates to a steelmaking stirring desulfurization process in the metallurgical industry, in particular to a novel KR molten iron desulfurization dual-motor stirring head control system and method. Background technique [0002] In the KR hot metal desulfurization system, in order to control the cost and facilitate maintenance, the dual-motor control mode is generally adopted, refer to the attached figure 1 As shown, two frequency conversion motors (1# motor, 2# motor) drive the mixing head through the gearbox. The control method of these two frequency conversion motors is generally to connect one motor (1# motor) to the frequency converter (1# Frequency converter) is set to speed closed-loop control, and the frequency converter (2# frequency converter) corresponding to another motor (2# motor) is set to torque closed-loop control. The 1# motor of the speed closed-loop control is used as the main motor, and the 2# motor of the torque close...

AI Technical Summary

Problems solved by technology

[0003] However, due to the time difference in transmitting the instantaneous torque of the master motor to the slave motor (mainly the transmission delay of the PROFIBUS-DP line or optical fiber line and the response delay of the PLC), the closed-loop control of the master-slave motor (especially the rotation of the slave motor) Torque loop closed-loop control ratio, integral and other parameter settings) during debugging, according to the different debugging levels of the on-site debugging personnel, it will also have a great impact on the synchronization of the two motors. In the end, the master and slave motors of the mixing head are often out of sync. Frequent grinding of teeth during work will have a negative impact on process production status and equipment life

In addition, the mixing system adopting this kind of master-slave control also has problems such as the need to replace the master-slave control after the failure of the main motor or the corresponding frequency converter.

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