Uporaba mikroračunalnika Raspberry Pi za vodenje in nadzor klimatizacijskega sistema

Vide, Žiga (author), Karer, Gorazd (mentor), Andonovski, Goran (comentor)

V diplomskem delu je predstavljena vzpostavitev krmilniškega sistema za vodenje klimatizacijske enote v novi poslovni stavbi podjetja TRAC d.o.o. Pri tem je namesto klasičnega industrijskega programirljivega logičnega krmilnika (PLK) uporabljen mikroračunalnik Raspberry Pi 4 Model B skupaj s programskim okoljem CODESYS V3.5. Za priključitev industrijskih signalov je uporabljena oddaljena vhodno-izhodna enota Siemens ET200SP, povezana preko protokola PROFINET, komunikacija z nadzornim sistemom pa poteka preko protokola OPC UA. Delo primerja izbrano rešitev s programskim okoljem TIA Portal, ki ga podjetje sicer standardno uporablja, in utemelji ekonomsko ter tehnično upravičenost alternativne platforme za projekte manjšega obsega s počasno procesno dinamiko. Opisana je implementacija krmilniškega programa, vključno z zajemanjem signalov in PID-regulacijo. Predstavljeni so alarmiranje, zaščita pred zmrzovanjem in zaščita pred kondenzacijo na ceveh hladilnega medija na osnovi izračuna temperature rosišča po Magnusovi enačbi. Osrednji del dela obsega eksperimentalno identifikacijo dinamičnega modela rotacijskega rekuperatorja klimatske naprave AHU001. Z odprtozančnimi stopničnimi preizkusi pri različnih hitrostih vrtenja rekuperatorja je bil identificiran proporcionalni model prvega reda, katerega parametri so bili uporabljeni za analitično nastavitev parametrov PI-regulatorja po metodi vodenja z notranjim modelom (IMC, ang. Internal Model Control). Izkazalo se je, da ojačenje procesa z naraščanjem hitrosti rekuperatorja izrazito pada, kar določa uporabno regulacijsko območje sistema.

• Language: Slovenian
• Keywords: Raspberry Pi, CODESYS, programirljivi logični krmilnik, HVAC, klimatizacija, PID-regulator, rotacijski rekuperator, identifikacija sistema
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FE - Faculty of Electrical Engineering
• Year: 2026
• PID: 20.500.12556/RUL-187221
• COBISS.SI-ID: 291473923
• Publication date in RUL: 09.09.2026

Secondary language

• Language: English
• Title: Use of a Raspberry Pi Microcomputer for Control and Supervision of an HVAC System

Abstract

This diploma thesis presents the design and implementation of a control system for an air-conditioning unit in a new office building of the company TRAC d.o.o. A Raspberry Pi 4 Model B microcomputer running the CODESYS V3.5 software environment is used instead of a conventional industrial programmable logic controller (PLC). Industrial signals are interfaced through a Siemens ET200SP remote input/output system connected via the PROFINET protocol, while communication with the supervisory SCADA system is carried out over OPC UA. The chosen platform is compared with the TIA Portal environment, which the company otherwise uses as standard practice, and its economic and technical suitability for smaller-scale projects with slow process dynamics is justified. The implementation of the control program is described, including signal acquisition and PID-control. Alarming and protective functions are also presented – freeze protection and dew-point-based condensation protection for the chilled-water piping, calculated using the Magnus formula. The central part of the thesis covers the experimental identification of the dynamic model of the rotary heat-recovery unit of air-handling unit AHU001. Using open-loop step-response tests at several rotor speeds, a first-order proportional model was identified, whose parameters were used to analytically tune a PI-controller by means of internal model control (IMC). The process gain was found to decrease markedly with increasing rotor speed, which determines the usable control range of the system.

• Keywords: Raspberry Pi, CODESYS, programmable logic controller, HVAC, air conditioning, PID-controller, rotary heat recovery unit, system identification