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Simulation-Based Study of Horizontal Axis Wind Turbine Behaviour under Harsh Climatic Conditions of Mongolia
(German-Mongolian Institute for Resources and Technology, 2026-05-27) Enkhjin B.; Supervisor 1: Ph.D. Lee, Sungchil; Supervisor 2: Ph.D. G.Gantuya
Wind energy is a key part of Mongolia's transition to clean electricity, but the country's harsh climate raises questions about whether wind turbines designed for moderate regions can operate safely in winters that drop below -30°C. This thesis investigates the fatigue behavior of a representative horizontal axis wind turbine blade made of glass-fiber reinforced polymer under such sub-zero conditions, using a chain of established simulation tools rather than physical testing. The reference machine is the GE 1.6-100, the model already installed in the first commercial wind farm of Mongolia in Sergelen. Real wind speed data measured at the GMIT campus weather station were used as the input. The aerodynamic loads were obtained from a Blade Element Momentum solver written in Python, which produced the flapwise and edgewise root bending moments at every wind speed in the dataset. These bending moments were then applied to a finite element model of the blade in ANSYS Mechanical, where a static structural analysis and the built-in fatigue tool predicted the life of the laminate. Three temperature-dependent S-N curves of glass-fiber reinforced polymer extracted from the OPTIMAT BLADES database were used to compare the response at room temperature, at -40°C and at +60°C. A modal analysis combined with a Fast Fourier Transform of the wind speed signal completed the picture by evaluating the resonance risk of the blade. The simulations show that, in dry isothermal conditions, the blade can sustain more than one hundred million cycles at the maximum flapwise bending moment, that fatigue performance is slightly better at -40°C than at room temperature, and that the spectral content of the wind at the natural frequencies of the blade remains below twenty-two percent of the dominant peak. These results form a baseline against which more complete future studies, including ice accretion, freeze-thaw cycles, dust erosion and a realistic internal blade structure, can be compared. The work supports the broader goal of replacing coal-fired electricity in Mongolia with reliable, properly engineered wind power.
Comparative Simulations of Thermal Management Strategies for EV LiFePO₄ Battery Modules in Mongolian Cold Climates
(German-Mongolian Institute for Resources and Technology, 2026) Bilguun D.; Supervisor 1: Prof. Dr. N.Odbileg; Supervisor 2: Prof. Dr. Kim, Yong Suk
Mongolia ranks among the world's coldest inhabited nations, with Ulaanbaatar averaging −25°C in January and the national record reaching −58°C. These conditions severely impair the performance of lithium iron phosphate (LFP) battery modules: at −40°C, available power may be reduced by up to 80% relative to room-temperature performance, and charging is not safely possible without prior thermal conditioning due to the risk of permanent lithium plating at the graphite anode. Standard battery qualification tests are oriented to major markets in the United States, China, and Europe and are typically conducted only down to −25°C, leaving the extreme cold end of the Mongolian operational range uncharacterised in the published literature. This thesis presents a comparative transient thermal finite element analysis of four individual thermal management strategies applied to a 12-series 1-parallel (12S1P) module of twelve CATL 100 Ah prismatic LFP cells, together with a fifth combined and optimisation system (System E) that evaluates five sub-simulations pairing active and passive strategies under cold-start and summer overheating conditions. The four individual strategies are: (A) passive aerogel insulation (thermal conductivity k = 0.016 W/(m·K), 7.5 mm thick); (B) external positive temperature coefficient (PTC) resistive heating at 150 W applied through a 404.14 mm × 200.33 mm × 10 mm heater plate; (C) internal alternating-current (AC) self-heating, modelled as a volumetric heat generation rate of 54,538 W/m³ applied uniformly to all twelve cell bodies; and (D) a passive RT35 phase change material (PCM) buffer, modelled as a 404.14 mm × 200.33 mm × 3 mm slab on the module face opposite the heater plate. Three-dimensional geometry was developed in Autodesk Inventor Professional 2026 and imported into ANSYS Workbench 2025 R2 for transient thermal analysis. Six Transient Thermal systems are defined: a Baseline representing the unprotected module, and Systems A through E. Two test types are used: heat retention tests (module starts at +20°C, cools in −40°C ambient) and heat-up tests (module starts at −40°C, warmed by active heat sources). Key results are as follows. System A (aerogel alone) extended the time before the minimum cell temperature crossed 0°C from 100 s (Baseline) to 3,140 s, a 31-fold improvement providing approximately 50 minutes of additional passive protection. System B (PTC heater alone) failed to bring any cell to 0°C within 4 hours; the minimum temperature after 14,400 s was −14°C. System C (AC self-heating alone) achieved 0°C minimum in 5,680 s. System D (PCM alone) extended minimum temperature protection by only 105 s, confirming aerogel outperforms PCM by a factor of 29 as a passive cold-weather strategy. System E identified the combination of AC self-heating with aerogel insulation (E2) as optimal: 0°C minimum reached in 2,200 s (36.7 minutes) consuming only 0.458 kWh, the best efficiency of all active strategies tested. Adding PCM to active cold-start systems was found to be detrimental, extending warm-up time in both E3 and E4 by absorbing heat that would otherwise warm the cells. System E5, a summer overheating scenario, showed that the aerogel-wrapped module reached the 60°C critical discharge temperature limit from 20°C in 4,680 s (78 minutes) under moderate driving heat generation at +35°C ambient, confirming that aerogel-based designs must incorporate provisions for warm-weather thermal management. The comparative results provide a quantitative engineering basis for selecting and designing battery thermal management systems suited to Mongolian operating conditions. This work represents the first systematic module-level finite element comparison of these four strategies under the specific thermal conditions of Mongolia, addressing a gap in the existing engineering literature.
Design and Transient Performance Analysis of a Functionally Graded Rotor for High-Speed Synchronous Reluctance Motors in Electric Vehicle
(German-Mongolian Institute for Resources and Technology, 2026-05-01) Javkhlan, B; Supervisor 1. Prof. Dr. Lee, Sungchil; Supervisor 2. Prof. Dr. Kim, Young Suk
This thesis presents the design and performance analysis of a functionally graded (FG) rotor for a high-speed Synchronous Reluctance Motor (SynRM) targeting 150 kW at 18,000 RPM for electric vehicle applications. The core problem addressed is the conflict between mechanical strength and magnetic efficiency in high-speed SynRM rotors, where steel bridges provide structural support but cause q-axis flux leakage that reduces torque production. A functionally graded material system using M-19 silicon steel and phosphor bronze is proposed to replace steel bridges. Three rotor configurations were compared: a solid baseline rotor, a standard bridged rotor, and a bridgeless FGM rotor with phosphor bronze barrier fill. The rotor geometry was designed in Autodesk Inventor Professional as individual lamination profiles. Electromagnetic simulation was performed using FEMM 4.2 in the magnetostatic regime, where a 24-slot 4-pole motor was excited with balanced three-phase peak currents of I_A = 300 A, I_B = I_C = −150 A. Flux linkage, phase inductance, and Maxwell stress tensor torque were extracted from the circuit properties panel for each rotor case. Structural analysis was conducted in ANSYS Static Structural 2026 R1 on individual lamination layers under a rotational body load of 18,000 RPM, with the shaft bore face fixed as the boundary condition. Full rotor stack simulation was not possible due to computational hardware limitations. Electromagnetic results show the FGM rotor reduces q-axis flux leakage by 7.3% and improves the saliency indicator by 58% compared to the standard bridged design. Structural results show the standard steel rotor reaches 289.86 MPa at the barrier ribs with a safety factor of only 1.24, while the FGM rotor reduces peak strain by 58.4% and raises the safety factor to 1.79. Peak copper loss is calculated at 4.08 kW, requiring water jacket cooling. The phosphor bronze fill also improves rotor thermal conductivity from 23 to 50 W/mK. The proposed design uses no rare-earth materials, presenting a sustainable and cost-effective alternative for high-speed EV traction motors and contributing to the development of domestic electric vehicle engineering capability in Mongolia.
Automated trash sorting system
(German-Mongolian Institute for Resources and Technology, 2025-11-14) Sumiyajid Ulziibayar,; Supervisor 1:Myagmarjav. B; Supervisor 2: Narangarav.T
The proper sorting of household waste remains a significant challenge globally, often hampered by complex logistics and inconsistent public participation. This thesis presents the design and implementation of a cost-effective, automated trash sorting system specifically engineered to address the issue locally, in Ulaanbaatar city, at the request of Nalaikh District. The system aims to actively motivate and train the population, particularly children in educational settings, to sort recyclables responsibly. The initial project scope, which involved sorting six distinct waste types using multiple sensor modalities, was narrowed due to practical and economic constraints, particularly the difficulties associated with safely storing glass and organic waste within a compact unit. We have decided to use an integrated embedded system built around a Raspberry Pi and an ESP32 microcontroller. This system utilizes a camera-based machine learning model for classification, categorizing inputs as Plastic Bottles, Metal Cans, or Others (namely, paper, cardboard, glass, and organic materials), combined with weight sensor data. The mechanical separation is handled by a combination of a stepper motor and/or a servo motor integration to make the unit more scalable. One of the key elements of the project is the development of a server-based tracking and reward system, which leverages the motivation of group competition to promote consistent usage and habit formation among its target demographic. The system achieved a classification accuracy exceeding 90% in testing, demonstrating that a highly focused, integrated engineering approach can provide a scalable and financially viable tool for improving localized recycling compliance.
Predictive Maintenance of Electric Motor-System Using Vibration Analysis
(German-Mongolian Institute for Resources and Technology, 2026-05-01) Boldbaatar, Tuvshinbayar; Supervisor 1: Prof. Lee, Sungchil; Supervisor 2; Prof. Kim, Young Suk
Electric motors are widely used in industrial and mining operations, where their reliability directly affects productivity, safety, and maintenance costs. Unexpected failures can lead to significant downtime, making predictive maintenance an important strategy for improving system performance. This study investigates using vibration analysis to detect common mechanical faults in electric motors, including bearing defects, misalignment, and unbalance. Publicly available datasets, including the Case Western Reserve University (CWRU) bearing dataset and a belt-driven rotating shaft system dataset from the Mendeley Data repository, are used to analyze vibration signals under both normal and faulty conditions. For bearing fault detection, we compare signals from healthy and defective cases using time-domain, frequency-domain, and envelope analysis, allowing us to examine both general vibration behavior and high-frequency impacts. The data are sampled at 12 kHz, with the motor operating at 1797 rpm, enabling identification of localized inner race defects. In addition, vibration data from a belt-driven rotating shaft system are used to study unbalance and misalignment. Normal operation is compared separately with each fault condition using time-domain and frequency-domain methods. The shaft operates at 1238 rpm, and Fast Fourier Transform (FFT) analysis focuses on the shaft rotational frequency (1X) and its harmonics (2X and 3X) for fault identification. The results show that different fault types produce distinct vibration patterns, though the clarity of detection depends on sensor placement and measurement direction, allowing clear fault differentiation. A combination of time-domain features, harmonic analysis, and envelope methods provides a more reliable diagnosis than using a single parameter. Overall, this study demonstrates that vibration analysis can effectively detect both motor-related and externally induced faults, supporting early fault detection and improving predictive maintenance strategies.