Moon-Seon Jeong

A Study on Design of 50kW PMSG for Micro-grid Application

In this paper, the 50kW aerogenerator which is applicable to the microgrid was designed and analyzed by using commercial simulation program Maxwell 2D. Particularly, the suggested PMSG to reduce the cogging torque introduced the offset and skew concept. The suggested optimal value of offset and skew was decided by 2mm and 60 degree of electric angle. The simulation results of the PMSG when load operation condition showed the average harmonic distortion 1.3%, voltage 322.41V, current 94.95A, and iron loss 9.73W, eddy current loss 73.68W, copper loss 3.52kW. The capacity of aerogenerator calculated 61.56kW, and the suggested design process can be applied to higher capacity generator.

A Study on Optimization Design of Off-grid Hybrid Power Generation System

The majority of electric power in the domestic manned islands with off-grid power system is supplied by the diesel generators. However, in the case of off-grid islands the fuel cost is more expensive to inland areas and difficult to transport them to islands. So the development of renewable energy system using natural resource have been recently introduced. But renewable energy that depend on the natural environment, it is necessary to organized the hybrid system with existing diesel engine because the energy is difficult to maintain stable electric power. This paper presents the results of a feasibility study of hybrid system with energy storage system such as wind, solar, battery and diesel engine. The study included off-grid island as the Seogeochado islands located in Jeolanamdo Province. And, the paper proposed a optimal capacity of hybrid system configuration to maintain carbon free with minimum investment cost. the analysis of economic adaptability performed by HOMER program.

A Study on non-linear trajectory shaped apparatus applied solar tracking device

In this paper, 1-axis tracking mechanism of solar-cell panel, which is able to rotate from -90 degree to +90 degree for maintaining always perpendicular between solar-cell panel and sun, was analyzed. This paper propose the non-linear shaped guidance and analyze mathematical formulation of non-linear shape. This analysis shows that it is able to identify the non-linear shaped guidance. Especially, even though the length of rotating link have changed, the non-linear shaped guidance could be confirm with proper size. As effectiveness of this result, 10% efficiency rising is estimated compared to the conventional 1-axis tracking mechanism and also optimal non-linear shaped guidance can be suggested for various size of solar-cell panel. Therefore the flexible mass-production is possible for various size of non-linear shaped guidance.

A Study on Design of Control Device on Small Wind Generator Using 2-Level Boost Converter

The small wind generator with existing mechanical control system has a frequent failure and malfunction, and its maintenance is difficult. In this paper, an electric control method using a boost converter for small wind generator was suggested. The suggested 2-level boost converter control device was manufactured and its experimental operation were conducted on a wind generator with 200 [W] capacity. As a result of experimental device, the control by a boost converter was executed at the point that the output voltage of a wind generator became 36 [V] so it could be identified that the output voltage of a wind generator diminished and then it became 0 [V] after 5 [sec]. Besides, in case of applying the method suggested in this paper to a small wind power generation facility for street lights, it is expected to reduce its maintenance by preventing a frequent failure of a generator and to improve its utilization rate.

The study on prediction of power generation of offshore wind farm of western and southern coast utilizing offshore buoy meteorological observations data

Given the massive early investment needed for the construction of large offshore wind farms, the ROI (return of investment), which can guarantee sufficient profitability, should be secured in advance. The highest priority in terms of determining profitability is to estimate the power production volume of an offshore wind farm based on surveyed wind resources. The maritime measurement of wind resources in Korea has only been performed at one point in the water off the coast of Wido. And the measurements released by the Korea Meteorological Administration were used, as there are no available long-term measurements for other areas. This paper suggested some analysis results that have been collected using a 4[m] tall meteorological-purpose buoy facility installed at the West Coast. The measured wind speeds were corrected at a height of 80[m], which is the average hub height of wind power generators. In addition, an offshore wind farm consisting of 34 3[MW] wind power generators were designed using WindPRO in order to estimate annual power production capacity and utilization rates. The provided average wind speed was 4.92[m/s], and a wind speed of 6.66 [m/s] was obtained by correcting the average wind speed at a height of 80[m]. The power generation capacity and utilization rates of a 100[MW] offshore wind farm, designed using WindPRO based on the corrected data, were estimated to be 294,313.9[MWh] and 32.9[%], respectively. As power production using tidal currents was envisaged to be possible due to the average depth of the water at which an offshore wind farm is to be located was found to be 34[m], it was thought that the design of a hybrid wind farm combining wind power with tidal current power would prop up the economic feasibility of the farm.

A Study on Optimal Capacity Design of Renewable Combined Power System for Energy Self-Sufficient Island

The recent trend is that diesel power generation on islands where its prime cost for power generation is high is replaced by new and renewable energy. Therefore, south Jeolla province is progressing the construction project of self-sufficient islands for the areas where power is supplied by depending on diesel generators, which is the project that power is supplied through eco-friendly energy source using sunlight, wind power and energy storage device etc. However, it is difficult to construct new and renewable energy source with the capacity to respond to the load perfectly due to its environmental and geographical conditions regarding capacity design of new and renewable energy. Besides, Microgrid design considering appropriate capacity design of the system components and efficient operation is required through the analysis of climate conditions and load patterns from the design stage for optimal composition of a hybrid system with economic feasibility. Therefore, this study is aimed to conduct a research on optimal combination, capacity calculation and economic feasibility by comprising a hybrid power generation system which will replace 40% of power generation by diesel as new and renewable energy source for Geomun Island where has more than 300 households and requires expansion of the facility among islands located in southwest coast.

A Study on Feedforward Compensation Method of IPMSM for EV with Non-sinusoidal BEMF

In the case of the Back EMF voltage contains the harmonics, the motor torque ripple and vibration is occurred by the current pulsation, because IPMSM control algorithm is the model which is assumed that it contains a sinusoidal Back EMF voltage. To improve ride quality, in the case of IPMSM for EV, improving the torque control characteristics is necessary. Therefore, there is a need to minimize the influence of the harmonics. In this paper, the investigation to decrease the current distortion factor has been performed for improving torque control characteristics by applying the non-sinusoidal Back EMF to IPMSM model.

A Study on Development of Test Site for Wind Turbine Prototype Test

It is evident that in the wind energy business as an economic activity there is a close relationship between the wind speed and the revenues. The wind turbine test facility for wind turbine accreditation is intended to be used by the industry for testing of both main components and systems. This paper suggest the wind test site for certification of prototype wind turbine with international regulations. The test site has an environmental permit for wind turbines with a maximum hub height of 120m and a rotor diameter up to 120m, and can accommodate prototypes with installed electrical powers up to 5MW each. A wind turbine manufacturer can lease the location for a period of type certification. And also researchers are the development of new methods for measuring the influence, performance and durability of the components, a mathematical and numerical modelling of component responses by using the site.

A development of battery monitoring and management system

In case of installing a room of a battery for recharging an electric car, it is necessary to have a system to keep the best state of a battery and to control the recharge and discharge of power. This paper is about the measuring module for the status information of a battery and the development of a battery management system to manage individual battery in a room of a battery with 120kWh grade. It was designed to measure 400V for the maximum voltage of a battery, and 300A for the electric current and (-10 ~ 50) °C for the temperature. By manufacturing a measuring module, the voltage, electric current and temperature were measured for nickel-metal hydride battery, and a system managing the recharge and discharge of power of a battery in real time was developed by using LabVIEW program.

A Development of Dedicated Data Logger for Wind Resource of Small Wind Power Generator

To install a wind power generator, the survey on the wind environment resources must be conducted in advance. The survey on the wind environment resources is to collect and analyze data regarding the wind speed and direction on a data logger. The data logger consists of a sensor, signal processing circuit and storage device. According to the analysis of the stored data, the amount of power generation by the types of generators can be predicted and the most optimal generator including safety grade can be selected, and in case of installing a generator in the future, it can be utilized as basic data regarding supporting base and foundation construction method of survey points. Data logger was developed for a small wind power generator that is suitable for the international standard(IEC 61400) by using DSP-F28335 micro controller in this paper. It was developed to measure the wind speed of 1 [m/s]~17 [m/s], the wind direction of 0 []~359 [], and temperature of -30 []~50 [], and the comparative experiment with other companies` data loggers was conducted, and an error was measured to be less than [m/s] for wind speed and less than +1 [] for wind direction.