CHUN HSIN CHUN CHNAG

Dr. CHUN HSIN CHUN CHNAG


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 May 2022 in Applied Sciences
Verified
Journal Article
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AJAnindya Sundar Jana
Anindya Sundar Jana
Chang-Hua LinChang-Hua Lin
Chang-Hua Lin
TKTzu-Hsien Kao
Tzu-Hsien Kao
CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
The application of the high gain boost DC-DC converter is gaining more attention due to an increasingly wide range of applications for sustainable green energy solutions, as well as other high voltage applications. In this study, a modified high gain quadratic boost converter is proposed using a single switch. The proposed topology is a member of the family of the non-isolated category with a common ground feature and can operate in a wide range of duty ratios, and is able to provide the required voltage gain. In this proposed circuit configuration, a dual voltage boost cell was formed by incorporating two capacitors in series with two inductors of a conventional quadratic boost converter. Additionally, a capacitor was integrated with a second voltage boost cell. This special configuration increases the voltage gain as well as reduces the voltage stress across the switch. To show its feasibility, a 200-W prototype setup with 48 V input and 400 V output was designed, and the required PWM signal was fed from the microcontroller unit. A detailed analysis of the design parameters and losses are formulated and are shown in this paper. The simulation was performed in SIMPLIS software, and the experimental results agreed with the obtained output voltage gain. The proposed topology showed a peak efficiency of 94.5% at 150-W output power after considering the power losses in all the components of the PCB.

23 December 2021 in Polymers
Verified
Journal Article
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TTTun-Ping Teng
Tun-Ping Teng
WCWei-Jen Chen
Wei-Jen Chen
CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
Graphene heat-dissipating coating (GNHC) of 0.6 wt % GN concentration is utilized to promote the cooling performance of automotive light-emitting diode (LED) lamps. Three cases are studied as follows: Case 0 is the original automotive LED lamp as the baseline. Case 1 is to apply GNHC to reduce the thermal resistance of the junction surfaces between the components of automotive LED lamps. The aluminum fin radiator of Case 1 is further coated with GNHC on the surface that becomes Case 2. The spectrum, illuminance, power consumption, and surface temperature are measured at different ambient temperatures (Ta) to fully evaluate the feasibility of applying GNHC to improve cooling performance and the impacts on the related characteristics of automotive LED lamps. The results show that the maximum illuminance efficacy of Case 1 and Case 2 with high beam, irradiation angle of 0 degrees, and Ta of 80 °C is 11.03% and 8.70% higher than that of Case 0, respectively. The minimum temperature difference of heat dissipation path of Case 1 and Case 2 with high beam, irradiation angle of 90 degrees, and Ta of 80 °C is 6.41% and 5.33% lower than that of Case 0, respectively, indicating GNHC as a promising coating material for improving the cooling performance of automotive LED lamps.

11 November 2022 in Applied Sciences
Verified
Journal Article
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CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
TTTun-Ping Teng
Tun-Ping Teng
TTTun-Chien Teng
Tun-Chien Teng
In this study, the authors propose a method for evaluating the influence of ambient temperature (Ta) on the optical characteristics and power consumption of a LED lamp used for the automotive headlamp, which helps the designer to figure out the acceptable range of the ambient temperature for the LED lamps to work well in the practical case. The LED lamp was fixed on the test holder and placed in a fixed position in the air circulation temperature control oven to measure the illuminance, spectrum in three different directions, and power consumption under various Ta. The experimental results indicate that Ta has little effect on the correlated color temperature (CCT), chromaticity coordinates, and angular distribution of the emitting light. In contrast, Ta has a significant effect on the lamp’s resistance, thus affecting illuminance and power consumption. When the Ta increased from 30 °C to 60 °C, the illuminance of the low beam and high beam decreased on average by 16.6% and 21.7%, respectively, while the power consumption of the low beam and high beam decreased on average by 21.4% and 22.2%, respectively. The drop in the luminous flux output indicates the probability of originally qualified automotive LED headlamps becoming unqualified in high Ta.

10 December 2021 in Applied Sciences
Verified
Journal Article
Open access
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YLYu-Hsuan Lin
Yu-Hsuan Lin
LLLi-Fan Liu
Li-Fan Liu
Yi-Hsuan HungYi-Hsuan Hung
Yi-Hsuan Hung
CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
The performance and efficiency of green energy sources in electric vehicles (EVs) are significantly affected by operation temperatures. To maintain the optimal temperatures of a hybrid energy system (HES), an innovative hybrid thermal management system (IHTMS) was designed. The IHTMS contains a coolant pump, a heat exchanger, a proportional valve for hybrid flow rates, five coolant pipes, and three electromagnetic valves to form two mode-switch coolant loops. A Matlab/Simulink-based simulator of the IHTMS was constructed by formulating a set of first-ordered dynamics of temperatures of coolant pipes and energy bodies using the theories of Newton’s law of cooling and the lumped-parameter technique. Parameters were majorly derived by measured performance maps and data from the experimental platform of the IHTMS. To properly manage the optimal temperatures, four control modes were designed for inner-loop form and outer-loop form. For the experimental platform to verify the simulator, two power supplies generated the waste heat of dual energy sources calculated by the driving cycle and vehicle dynamics. Simulation results show that the temperatures were controlled at their optimal ranges by proper mode/loop switch. With the inner-loop mechanism, the rise time of optimal temperature decreased 27.4%. The average simulation-experiment temperature error of the battery was 0.898 °C; the average simulation-experiment temperature error of the PEMFC was 4.839 °C. The IHTMS will be integrated to a real HES in the future.

12 July 2026 in Journal of Thermal Analysis and Calorimetry
Verified
Journal Article
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CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
GWGuan-Xun Wang
Guan-Xun Wang
Hwa Dong LiuHwa Dong Liu
Hwa Dong Liu
This study proposes a temperature-dependent control strategy for improving the thermal management performance and energy efficiency of electric scooters under varying ambient conditions. A heat-exchange-based experimental platform was developed to replicate real vehicle operation for a 6.4-kW electric scooter, with ambient temperatures controlled between 30 and 50 °C. The proposed strategy dynamically adjusts the water pump duty cycle based on real-time coolant temperature, which reflects the thermal states of key components, including the traction motor and the motor control unit (MCU), eliminating the need for complex optimization algorithms. Experimental validation was conducted under both the WMTC Part 1 driving cycle (2400 s) and a constant-speed condition of 50 km h–1 (1100 s). The results demonstrate significant energy-saving performance. Under the WMTC Part 1 cycle, the proposed strategy reduced average pump power consumption from 18.35 W to as low as 0.94 W at 30 °C, achieving a maximum power reduction of 17.41 W and an energy improvement rate of 94.86%. Similarly, under constant-speed operation, the maximum power reduction reached 16.38 W, with an energy improvement rate of 89.68%. Across all tested conditions, the coolant temperature—representing the thermal behavior of the motor and MCU—remained well controlled, with deviations within approximately 0.17–1.59 °C, indicating effective thermal stability. These findings confirm that the proposed rule-based control strategy can significantly reduce energy consumption while maintaining adequate thermal protection for critical components. The approach offers a practical and low-complexity solution that can be readily implemented in vehicle control units (VCUs) or embedded systems. This makes it particularly suitable for small electric vehicles operating in high-temperature environments, with potential benefits for improving overall energy efficiency and extending driving range.

23 April 2020 in Energies
Verified
Journal Article
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CCCHUN HSIN CHUN CHNAG
CHUN HSIN CHUN CHNAG
HCHsuan-Yung Chang
Hsuan-Yung Chang
Yi-Hsuan HungYi-Hsuan Hung
Yi-Hsuan Hung
CWChien-Hsun Wu
Chien-Hsun Wu
JXJI JIA XU
JI JIA XU
This study developed a mechatronics platform for a seven-mode vehicle-oriented powertrain system. The innovative “all-in-one” concept was used for flexibly arranging various power or energy sources to be combined for various hybrid powertrains. Hence, it significantly reduces the cost and human resources for evaluating new-type power systems or developed vehicle control strategies on the same experimental platform. In this study, three power sources were chosen for providing hybrid power. The first source is a 125 c.c. spark ignition (SI) engine, where a controllable throttle valve governs the output torque, while a fuel meter measures the consumed fuel. The second one is a 1.5kW hub motor, where a motor control unit (MCU) and a 48V lithium battery pack properly provide the required electric power. The third source is an air engine, where a 220V air compressor and other components provide the pneumatic power. For the experimental platform, a developed Matlab/Simulink package receives the measured signals and sends the control commands to actuators. Through the on/off state control of three controllable e-clutches, three single-source modes, three dual-source modes, and one three-source mode (3+3+1) can be conducted. A 1.1kW/24V magnetic powder brake emulates the road load. The results show that three dual-source modes and a three-source mode were successfully operated. The efficiencies, torques and speeds, mass flow rates, etc. have been measured and calculated. This platform is aimed for the research fields of green energies, advanced powertrains, and power flow management.