Merilnik temperature z galvansko ločenimi termočleni

JEREB, DAVID (author), Smole, Franc (mentor)

V tem delu je predstavljen proces načrtovanja, izdelave, kalibracije in preizkušanja merilnega vmesnika za temperaturo z galvansko ločenimi vhodi za termočlene in komunikacijo po vodilu CAN. Merilni sistem podpira merjenje temperature na 16 kanalih hkrati s termočleni tipa K. V takem sistemu je merilno vezje preko termočlenov galvansko sklopljeno z merjencem. Vhodna vezja merilnega sistema imajo zato galvansko ločitev, kar nam omogoča merjenje temperature tudi na prevodnih delih, kjer se pojavijo neničelni potenciali (npr. ponor močnostnega tranzistorja). Konfiguracija in kalibracija merilnega sistema se izvajata po vodilu CAN. Merilnik podpira okrnjeno različico protokola CANopen. Ta protokol je bil izbran, ker je implementiran tudi na elektromotorskih krmilnikih, za testiranje katerih so bili izdelani ti merilniki. Rezultat projekta je uspešno izdelan merilni sistem, ki se bo v prihodnosti v manjši seriji izdelal na proizvodni liniji podjetja za interno uporabo.

• Language: Slovenian
• Keywords: temperatura, termočlen, večkanalni, tip K, CAN, CANopen
• Work type: Master's thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2019
• PID: 20.500.12556/RUL-111080
• Publication date in RUL: 23.09.2019

Secondary language

• Language: English
• Title: Thermometer using galvanically isolated thermocouples

Abstract

The thesis describes the process of development, building, calibration, and testing of a temperature measurement device with galvanically isolated thermocouple inputs and CAN communication interface. The device supports simultaneous measurement of 16 channels with K-type thermocouples. In this sort of measurement system, the measurement circuit is electrically connected to the device under test. The input circuit is, therefore, isolated galvanically to allow the thermocouple to be bonded to electrically conductive parts where non-zero potentials may appear (e.g. the drain of a power transistor). Configuration and calibration of the device are controlled through the CAN communication interface. The device supports a streamlined version of the CANopen protocol. This protocol was chosen because it is also used on electric motor drives, which will be tested using these devices. The result of this project is a successfully designed measurement system which will be produced for internal use in a small batch on the company production line.

• Keywords: temperature, thermocouple, multichannel, K-type, CAN, CANopen