Alternative Ways t o Control a n Object u sing Plc S7 1200 Controller

Abstract

The paper concerns an alternative ways of object control using S7 1200 controller. Author’s solution is based on an external Matlab program with Simulink extension. Standard ways of controlling an object with the use of a controller to control and analyze the operation of this object use either the controller itself or a graphical representation of the system using an HMI operator panel. An alternative way of controlling a three-phase electrical motor using an external software Matlab with Simulink extension was invented and created in the university laboratory. Algorithm of controlling the object has been created in Matlab environment, through which it is possible to control the object and to read parameters of voltage, output current or even torque. The program is fully compatible with TIA Portal software, which uses TSEND_C and TRCV_C function blocks to exchange data with a PC running Matlab. The entire control process is based on the TCP protocol, while the object is connected through the inverter to the controller using the Modbus RTU protocol. A comparison of the presented solution with currently used solutions has been made. At the end of the article, all advantages and disadvantages of the discussed solution are presented, as well as personal comments on the solution.