Design And Development Of Instrumentation And Control System Hardware And Software Modules For The Cryogenic Test Facility

Abstract

The Helium plant test facility needs compressors and turbines as compression and expansion machines respectively to produce cold helium for test of cryogenic components. Cryogenic turbines are significantly smaller in size compared to those for room temperature applications, but rotation speed is high, about few lakhs of rpm and hence it has contactless gas bearings. This test facility will be used to test these turbines, compressors, different types of plate fin heat exchangers and helium purifiers. Hence, such cryogenic test facility needs large number of sensors (temperature, pressure, flow, speed, vibration, level etc) and valves for diagnostic purposes. The project work includes the design of the control system hardware and the software architecture and process logics developed for different operational scenarios of cryogenic test facility. To operate the facility, PLC based hardware having three nodes with the performance in the order of 100 msec over Ethernet for data exchange between nodes is required. Around 500 I/O channels including pressure control valves, on/off valves, temperature sensors, absolute and differential pressure measurement points, flow measurements, one set of speed measurement sensors, one set of vibration sensors, level sensors, etc are required to communicate with PLC. Process flow chart (PFC) logic and control algorithms development along with a proto- type simulator to evaluate the concepts. Operational sequence of different components with rate of opening/closing (including PID loops) of valves has been conceptualized for safe operation during normal and off-normal operations in the test facility. Concepts to be developed for data management like logging, storage, display, process, access, generation of experiment recipes for automation in operation using Siemens PLC.