Design and Development of Instrumentation and Control System for Cryogenic Heat Exchanger 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. 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. Different types of 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. This project work involves a Cryogenic temperature control system based on temperature monitor having multiple channels has been used for recording and monitoring the various temperature in Cryogenic Heat exchanger which is further used for liquid helium test facility. The effectiveness of heat exchanger can be maintain by the temperature that will be measured at inlet and outlet of the prototype heat exchanger. Various sensors has been placed in the system and different temperature and pressure readings has been taken in LabVIEW where it can be monitor and log the varying temperature value of a cryogenic heat exchanger with the help of data acquisition system (DAQ). Siemens PLC (Programmable logic control) S7 300 has been introduced for controlling the cryogenic heat exchanger process.