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The Northeast Asian Super Grid, initially proposed over a decade ago as a collaborative effort among countries like Mongolia, Korea, China, and Japan, has faced delays in implementation. The focus has been on establishing an ultra-high voltage direct current transmission network to supply electric energy from Mongolia's renewable-rich desert to China, Korea, and Japan. However, challenges in bridging interests and fostering cooperation have impeded progress. This research aims to shift direction by utilizing existing infrastructure to rejuvenate energy trade between neighboring nations, with a primary emphasis on sustainable energy.
This study proposes a practical output current measurement system in a three-phase inverter with a single printed circuit board (PCB) Rogowski coil sensor inserted in the bus between the DC-link capacitor and the power semiconductor module. This system demonstrates its advantage over conventional output current sensors, such as the Hall effect current sensors, in terms of the size, weight, operation temperature and cost. The system can be applied to 6-in-1 power modules as it does not require sensors in the inverter phase legs. In our previous works, we have developed a method called “envelope tracking”, which is used in this system as well. This method traces the switching current instead of the output current to reproduce the output current signal in real-time. Envelope tracking successfully reproduced the output current waveform for single phase inverters under certain conditions. However, a large error is observed in the three-phase inverter demonstration under a high switching frequency (narrow pulse) or when the switching of different phases overlap each other. These errors must be completely suppressed to implement the system for feedback control in three-phase inverters. In this study, a new analog basis output current waveform reproduction system is introduced to suppress the above mentioned errors. This system is implemented in a three-phase insulated-gate bipolar transistor (IGBT) inverter and successfully reproduces the output current with a single PCB sensor inserted between a 6-in-1 IGBT power module and DC-link capacitor, operating under a switching frequency of 3.5–7.0 kHz and output current of 6 A with DC-link voltage of 150 V.
Due to the COVID-19 the new Central Vaccine Storage facility was constructed and commissioned in August 2021. This research focuses on assessing the feasibility of implementing a solar energy system at the central warehouse of vaccine bio-preparations located at the National Center for Communicable Diseases (NCCD) in Mongolia. The critical healthcare facility's energy independence and sustainability can be improved by harnessing solar power. The Central Vaccine System (CVS) will depend on a solar power system to fulfill its electricity requirements, which can potentially meet a portion or the entirety of the CVS's annual electricity consumption. Through a comprehensive analysis of solar access and energy requirements, this research aims to provide valuable insights for promoting clean energy solutions in healthcare infrastructure, particularly in regions with limited resources. The research is to investigate different solar system solutions, including grid-connected solar systems integrated with battery energy storage (BESS). The goal is to identify the most optimal solution. The research process encompasses site surveys, data collection on electrical equipment, load calculations, solar system capacity assessment based on CVS electricity consumption, and identification of viable installation locations, and the formulation of solar system options, potentially incorporating grid-connected BESS. It highlights the advantages of solar energy, including clean and renewable power, potential cost savings, and energy independence.
It is important to estimate the energy required in ore processing to select the most affordable and efficient energy system for the integration of renewable resources into the mining industry. In the present work, the energy consumption for the concentrate of tungsten ore in Mongolia was theoretically predicted based on operational variations (particle size and the hardness of the tungsten ore) and different equipment. The energy was in the range from 0.48 to 1.32 kWh/t for the crushing stage, and a cone crusher was more suitable than a jaw crusher due to the particle size of feed material and product. The required energy in the grinding stage was from 6.22 to 11.88 kWh/t using a SAG mill or from 3.04 to 7.39 kWh/t using a ball mill. The further separation by a flotation consumed 4.83 kWh/t or by a shaking table consumed 1.29 kWh/t. The maximum energy consumption per hour for the whole process was estimated to be 2–3 MW, which was better to integrate with a hybrid renewable energy system. The sizing method Power Pinch Analysis was used to estimate the electric supply based on the combination of wind, biomass and solar resources, which was sufficient for the demand from the predicted range of energy.
Алтай сумын хосолмол нарны цахилгаан станцийн ажиллагаанд дүн шинжилгээ хийж, тулгамдаж буй асуудлуудыг тодорхойлов. Түүнчлэн нарны станцын ажиллгааг тогтворжуулах, сайжруулахад шаардагдах арга хэмжээг санал болгов. Энэхүү судалгааны ажилд үндэслэн Кангвоны үндэсний их сургуультай хамтарсан судалгааны ажлын хүрээнд суурилуулах микро сүлжээ, үүсгүүрт тусгах шаардлагатай зүйлийг мөн төслийн багт санал болгосон.
In this study, a power compensation control algorithm was designed and validated for com- mercial 100 kW medium wind turbine models for power compensation due to additional generator loss. Generally, torque control considering generator efficiency is applied to a controller of a medium wind turbine; however, a control corresponding to a decrease in generator efficiency due to the surrounding environment is not possible. There is a possibility that an additional generator loss may occur due to the surrounding environment of the wind turbine already installed, and accordingly, a power compensation control algorithm is required because power is expected to decrease. The power compensation control algorithms may be divided into three methods according to a control strategy, and three power compensation control algorithms were explained and designed. The proposed power compensation control algorithms were validated using DNV’s Bladed program. The simulation conditions were selected at an average wind speed of about 18 m/s and normal turbulence model (NTM) Class A, and the additional generator loss was assumed to be 15%. The simulation comparison showed that the original power control algorithm had a deviation of 15.00% from the rated power due to a 15% generator loss, and the designed three power compensation control algorithms had a deviation of up to 0.05%.
In this study, a pitch H-infinity control algorithm was developed for variable-speed– variable-pitch (VSVP) wind turbines to improve the rotor standard deviation of the wind turbines under normal and extreme wind conditions. The pitch H-infinity control algorithm only uses H- infinity control in the blade pitch control loop in the rated power region, and conventional torque gain scheduling algorithms are applied in the partial power region. The performance of this controller was verified using simulations of a 5 MW wind turbine using the commercial aeroelastic simulation code Bladed. The performance of the pitch H-infinity controller was compared with that of the conventional proportional-integral (PI) control algorithm under three different operating conditions: normal operating conditions without sensor noise, normal operating conditions with sensor noise, and extreme operating conditions without sensor noise based on the wind turbine design standard by IEC. Based on the simulation results with two different wind speed regions, namely, the transition region and the rated power region, it was found that the proposed pitch H-infinity controller showed better rotor speed standard deviation performance in the three operating conditions and achieved lower standard deviations of the rotor speed and the electrical power without affecting the mean electrical power.
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Жил ирэх тусам эрчим хүчний хэрэглээ өсөн нэмэгдэж байна. Эрчим хүчний үйлдвэрлэлийн дийлэнх хувийг шатамхай түлш бүхий үүсгүүр ашиглан гарган авч буй нь хязгаарлагдмал нөөцийн асуудлаас гадна байгаль орчинд хор хөнөөлтэй учир дэлхий дахин сэргээгдэх эрчим хүч буюу ногоон эрчим хүчийг ашиглаж эхлээд байна. Гэсэн хэдий ч бид ойрын жилүүдэд шатамхай түлш ашиглан эрчим хүч үйлдвэрлэх үүсгүүрийн технологийг бүрэн халах боломжгүй учраас эрчим хүчний системийг илүү үр ашиг сайтай, ашиглалтын хугацаа өндөр, хэрэгцээгүй зарцуулалтыг багасгах шаардлага тулгараад байгаа юм. Эдгээр асуудлуудыг чадлын электроникийн өндөр технологийг ашиглан шийдвэрлэх боломжтой. Чадлын электроникийн технологи нь эрчим хүчний системд шаардагдаж буй чадал, энергийг хангах зорилгоор өндөр хүчдэл, гүйдлийг боловсруулдаг цахилгааны инженерчлэлийн нэгэн салбар юм. Эрчим хүчний дамжуулах, түгээх сүлжээ, компьютерын сүлжээ, мэдээллийн технологи, томоохон үйлдвэрийн автоматжуулалт, сэргээгдэх эрчим хүчний систем, электрон тоног төхөөрөмжийн тэжээлийн үүсгүүр зэрэгт чадлын электроникийн технологийг өргөнөөр ашигладаг. Энэхүү судалгааны өгүүллийн хүрээнд МУИС-ийн чадлын электроникийн судалгааны лабораторийн судлаачдын зүгээс эрчим хүчний системд тулгарсан асуудлууд, сэргээгдэх эрчим хүч, эрчим хүчний тархмал үүсгүүр бүхий системд тулгарсан асуудлуудад шийдвэрлэх ямар шийдэл боловсруулж санал болгосон, өмнө ямар технологи ашиглаж байсан, одоо ямар технологи санал болгож буй, мөн туршилтаар ямар үр дүн гарсан зэргийг эмхэтгэв. Мөн цаашид ямар асуудлууд тулгарч болох, аль чиглэлд судалгаа шинжилгээг хийх шаардлага бий болж буй зэргийг тайлбарлав.
The energy consumption of Mongolia is increasing by an average of 6 percent per year , and now the installed capacity of the nationwide plants and the importing capacity from neighbouring countries are reaching potential limitation In order to make energy secure , we need to install new energy plants urgently . The govern ment has planned a number of projects in order to overcome the problems and meet the increasing consumption , some of them have already started implementation , but most of them are solutions for combined heat power plants . However , the fact that most of the investing countries have abandoned the traditional brown techno logy that emits greenhouse gases has become a risk factor in the im plementation of these projects . Since Mongolia has a vast territory and a scattered population , distributed energy generation is more optimal . This research paper will determine the current situation regarding the current legal environment , policy and financial support for distributed solar power generation . In addition , the problems faced in the development of distributed solar power generation and their solutions will be determined .
In developing countries (Mongolia), the majority of electricity consumption is household consumption, with peak hours in the evening. A possible way to reduce the peak load is an energy storage system that can support the grid. Batteries are widely used in the energy storage area, which is the most important component of an energy storage system. But batteries are expensive. This is difficult for developing economies, so it is possible to solve this problem by reusing batteries in electric and hybrid vehicles, which are highly toxic. Significant waste battery performance is degraded, and balancing at the cell / module level allows for full utilization of battery capacity, but the use of energy storage with battery bank makes the cost of an element / module level balancer too high. The study selected a method with a double tiered capacitor to balance the charge level at the battery bank level, which has the advantage of significantly reducing the cost of power electronics required for the balancer. The effectiveness of the chosen methodology was verified using simulation software.
Энэ ажлаар практик хэрэглээнд чадлын хагас дамжуулагч төхөөрөмжийн модулд бусад хамгаалалтын хэлхээнүүдийн хамт интеграц хийх боломж бүхий гүйдлийн сенсорыг судалсан. Шинэ төрлийн гүйдлийн сенсор нь PCB хавтангаар хийсэн Роговски ороомог бөгөөд инвертер, конвертерийн түлхүүрийн элементын гүйдэлийн өөрчлөлтөөс шууд хамааралтай хүчдэл үүсгэх төхөөрөмж юм. Эндээс үүсэх хүчдлийн утгаас системийн гаралтын хүчдэлийг энгийн үйлдлийн өсгөгчд суурилсан аналог хэлхээ ашиглан тодорхойлох боломжтой. Уг санаанд суурилсан гйүдэл хэмжих “Envelop tracking” аргыг 1фазын инвертер системд туршиж баталсан ба удирдлагын сигналын (SPWM) хэт нарийн мужд аналог хэлхээнээс үүдэх хэмжүүрийн алдааг засах аналог хэлхээний шинэчлэлтийг мөн хийж туршилтаар баталгаажуулсан.
Хураангуй—Сүүлийн жилүүдэд Гибрид болон цахилгаан автомашины хэрэглээ өсөн нэмэгдэж байна. Үүнтэй уялдаад гибрид болон цэвэр цахилгаан машины хуучирсан баттерейг хэрхэн ангилах, дахин ашиглах, байгаль орчинд сөрөг нөлөөгүйгээр устгах асуудал хурцаар тавигдаж байна. Энэхүү судалгаагаар гибрид авто машины хуучин баттерейг өрхийн зориулалттай нарны цахилгаан үүсгүүртэй хослуулан ашиглах боломжийг судалж, шийдлийг боловсруулан танилцуулав.
Нарны эрчим хүчийг өндөр чадлын системүүд ашиглаж эхэлсэн учир уг дунд болон бага чадлын системийг их чадлын төхөөрөмжүүдтэй зохицуулан ажиллуулахын тулд олон шатлалт инвертерийн технологийг 1975 оноос хөгжүүлэх болсон юм. Энэхүү өгүүлэлд олон шатлалт инвертерийн төрлүүд, хоорондын ялгарах онцлогийг болон аль төрөл нь илүү үр дүнтэй гэдгийг онолын хүрээнд хэрхэн судалсан талаар тайлбарлана. Тэрхүү онолын судалгааг бататгахын тулд PSIM симуляцийн програмыг ашиглан симуляцийг гүйцэтгэж түүнээс үүсэх үр дүн дээр дүгнэлт хийсэн болно.
Энэхүү судалгааны ажлаар ХӨСҮТ-д баригдахаар төлөвлөгдөж буй Вакцины төв агуулахын цахилгаан эрчим хүчний хэрэглээг Нарны цахилгаан үүсгүүр ашиглан хангах боломжийг судлав. ХӨСҮТ-ийн эзэмшил газарт вакцины төв агуулахын барилга барихад тохиромжтой байршлуудыг тодорхойлж, орчны барилгаас үүдэлтэй сүүдэрлэлтийг тооцоолон, оновчтой хувилбарыг сонгосон ба НЦҮ суурьлуулахад тохиромжтой барилгууд, тэдгээрийн дээврийн талбайд нийцүүлэн НЦҮ-ийн хүчин чадлыг сонгон, дээвэр дээрх сүлжээнд холбогдсон НЦҮ болон энерги хуримтлуур хосолсон системийг загварчлал болон симуляцийн аргаар тооцоолол хийж тодорхойлсон.
Nickel metal hybrid (NiMH) batteries are the most widely used batteries in hybrid electric vehicles (HEVs). Due to an imbalance among the individual cells caused by long-term use in HEV, a large number of NiMH batteries end up as toxic waste. Although the retired batteries cannot be employed as energy storage devices (ESDs) in electric vehicles (EVs) or HEVs anymore, they still have the potential to be reused as an energy source in small-scale distributed generation systems for households. However, the cell balancing operation is mandatory, even for those applications with lower power ratings. Hence, this paper proposes an active cell balancer that equalizes the state of charges (SOCs) of the imbalanced NiMH batteries using a generation control circuit (GCC). Along with the cell balancing circuit, an active power decoupling circuit (APDC) is applied. The purpose of the APDC is to not only achieve minimization of power pulsation caused by single-phase inverter, but also reliability enhancement of the entire system
To efficiently and safely reuse recycling batteries from electric vehicles in distributed generation systems, it is necessary to reduce the ripple currents caused by single-phase inverters. Thus, in this paper, an active power-decoupling circuit to reduce either high- or low-frequency ripple currents is proposed. The effectiveness of the proposed circuit is verified by simulation results.
Growth in the electric vehicle industry has resulted in considerable chemical battery waste, which requires special recycling processes. The power and recharging capacities of waste batteries are insufficient for the operation of traction motors. However, such batteries can be reused as power sources in residential renewable energy systems because household energy demands are much lower than those of electric vehicles. To enable this reuse, a battery pack should be equipped with an equalizer. Hence, in this study, we propose a battery module equalizer that adjusts the state of charge (SOC) of each battery module to the same point using a generation control circuit (GCC). By strategically changing the duty ratio of the GCC while detecting the overall voltage of the entire battery pack, the relative SOC of each battery module can be observed while the battery system is in operation. Although this approach uses only two sensors, it enables SOC observation for the entire battery pack, leading to reduced implementation costs and formfactor. The equalization current is further regulated based on the observed relative SOC. The simulation and experimental results demonstrate the rapid equalization capability of the proposed GCC-type equalizer during the discharging process.
Measuring the current of a power conversion system is imperative. So, we have developed a new method of measuring a three-phase inverter’s currents of all loads with a single current sensor. We successfully tested this method on a computer simulation and an experimental setup. Which showed that the method can be integrated into power inverters. We proposed an inexpensive analog circuit suitable for capturing current information from a tiny PCB Rogowski coil. It measures the current of the power inverter’s DC supply line and resynthesizes all load currents separately. This way it will reduce the size and cost of a power conversion system’s current measuring devices.
The rise of electric vehicles (EVs) and hybrid electric vehicles (HEVs) has resulted in increases in battery toxic waste. Although the powering and capacity characteristics of batteries deteriorate after use in EVs and HEVs, they usually retain enough potential for reuse as power sources in home energy systems, whose power requirements are much lower than those of EVs and HEVs. This study proposes an active cell equalizer that balances the state of charge (SOC) of nickel–metal hybrid (NiMH) batteries recycled from HEVs. In the proposed cell equalizer, two different circuits, e.g., a generation control circuit (GCC) and a power-decoupling circuit are integrated. Excessive energy is automatically transferred from a high-SOC cell to a low-SOC cell through the GCC. The power-decoupling circuit lowers the power pulsation caused by the single-phase DC/AC inverter. This reduces the low-frequency ripple current flowing into the battery pack, ensures safe operation and prolongs the lifecycle of the batteries. A prototype circuit with a three-stage battery pack is implemented in the discharging state and the obtained experimental results are analyzed to verify the equalizer functionality.
Health monitoring of the power conversion system is very important. Therefore, we developed a new method for measuring IGBT currents and reproducing average load current to monitor IGBTs. This method was successfully tested on an experimental setup which showed that the tiny PCB sensors can be integrated into intelligent power modules. We proposed an inexpensive analogue circuit which is suitable for capturing current information from a tiny PCB Rogowski coil. The sensors and corresponding circuit can be embedded into an Intelligent Power Module. The method was named “Envelop tracking” as it simultaneously measures the currents of the high and low side switches of a power converter and reproduces the upper and lower edges of the load current which can be averaged by further digital processing.
This paper proposes a practical current sensor integration in the intelligent power modules (IPMs) using simple PCB Rogowski coil sensors. The PCB sensors produce signals that proportional to the high frequency switching current from high and low side IGBTs. Then with only general-purpose Op- Amps and photo-couplers based integrator and sample and hold (S/H) circuits reproduce output current of the inverter. Specifically, the “envelop tracking” method has successfully proved on an experimental inverter setup. A significant accomplishment of an improved new analog circuit is the measurement during narrow pulse width around unity modulation index that leads to higher inverter output power.
This paper proposes a practical current sensor integration in the intelligent power modules (IPMs) using simple PCB Rogowski coil sensors. The PCB sensors produce signals that proportional to the high frequency switching current from high and low side IGBTs. Then with only general-purpose Op- Amps and photo-couplers based integrator and sample and hold (S/H) circuits reproduce output current of the inverter. Specifically, the “envelop tracking” method has successfully proved on an experimental inverter setup. A significant accomplishment of an improved new analog circuit is the measurement during narrow pulse width around unity modulation index that leads to higher inverter output power.
This paper presents possibilities to implement a capacity market in the Mongolian energy system and analyzes long term planning with different plants. Covering rapid increasing electric demand requires a complex solution in the energy system, which should support not only for the customer, and stakeholders. Proposed capacity market model for energy system in Mongolia, considering existing and new entrants of generation plants.
There is hazardous air pollution which mainly caused by raw-coal burning for heating purpose in Ulaanbaatar city. Although dominantly utilization of electricity-powered heaters is good solution for this issue as same as highly developed countries, local power system currently in use is already overloaded during evening period as most of residents actively use home electric appliances. Therefore, the authors aim to contribute for lessening the air pollution in Ulaanbaatar city by using latest technology development. The distributed generation system with renewable source and battery storage can be the bright solution. In this study, a suitable structure of the utility-interactive photovoltaic (PV) power generation system with energy storage (ES) for Mongolian households and its operation principle are discussed. Subsequently, an optimal operation algorithm, which has been selected based on a comparison aspect from economical, grid impact and PV penetration possibility, is suggested and verified through the experimental result. Development of the PV power generation system with ES will lead to a reduction in peak power usage as well as lessened amount of CO2 emissions.
Renewable energy includes solar and wind energy are depend on weather conditions and site-specific conditions. In this research work, we develop site-specific model for predicting energy productions from a photovoltaic (PV) system using machine learning based on weather data. The weather and the production data used in this work corresponds to a day averaged weather and power measurements collected from 2014. We compare two regression techniques, including Ridge and Random Forest. We evaluate the accuracy of each models using test dataset. Our results show that Random Forest regression-based model accuracy is highest with 0.99 and less features used.
This article discusses ways to reduce air pollution by using electricity as heating in low-emission house in Mongolian climate conditions. More than 60 percent of air pollution in Ulaanbaatar is caused by coal dust and ash from traditional heating of ger districts. The government of Mongolia has been promoting households to use electric heating while reducing tariffs on night time. This case study was done on 5kW floor plate heating system installed in a house with area of 56m2 located in Songinokhairkhan district, Ulaanbaatar city. Based on electrical consumption of the floor heating system, economic and environmental efficiencies were analyzed. Our chosen test object faces problems related to quality of power supply during peak load time. Therefore we optimized stand-alone PV system for the household using HOMER software.
Heating is biggest issue in Mongolia due to long and harsh climate. Specially, it is hard to keep the inside temperature of Mongolian ger such as traditional dwelling where herders often live in countryside. High air exchange inside of Ger is reason why hard to keep the temperature as constantly. During the cold season, herders have higher heat demand, but there is relatively less heating source. Most of herder households are applying small sized PV system due to nomadic life style. This research is aimed to develop a partial heating solution for the comfortance of the elder and younger children who stay longer in a Ger. The heating pad was modelled with the felt and heating material and measurement and experiment was conducted. In the experimentation, heater was supplied by small sized PV system as an electricity supply that herder households use commonly. The electrical energy for heat pad is optimized during the experiment dependent on ambient and indoor temperature. Moreover, a controller device that modifies pad temperature relating to ambient temperature was developed and it can fully satisfy the safety and the reliability. Key
This article discusses ways to reduce air pollution by using electricity as heating in low-emission house in Mongolian climate conditions. More than 60 percent of air pollution in Ulaanbaatar is caused by coal dust and ash from traditional heating of ger districts. The government of Mongolia has been promoting households to use electric heating while reducing tariffs on night time. This case study was done on 5kW floor plate heating system installed in a house with area of 56m2 located in Songinokhairkhan district, Ulaanbaatar city. Based on electrical consumption of the floor heating system, economic and environmental efficiencies were analyzed. Our chosen test object faces problems related to quality of power supply during peak load time. Therefore we optimized stand-alone PV system for the household using HOMER software.
Heating is biggest issue in Mongolia due to long and harsh climate. Specially, it is hard to keep the inside temperature of Mongolian ger such as traditional dwelling where herders often live in countryside. High air exchange inside of Ger is reason why hard to keep the temperature as constantly. During the cold season, herders have higher heat demand, but there is relatively less heating source. Most of herder households are applying small sized PV system due to nomadic life style. This research is aimed to develop a partial heating solution for the comfortance of the elder and younger children who stay longer in a Ger. The heating pad was modelled with the felt and heating material and measurement and experiment was conducted. In the experimentation, heater was supplied by small sized PV system as an electricity supply that herder households use commonly. The electrical energy for heat pad is optimized during the experiment dependent on ambient and indoor temperature. Moreover, a controller device that modifies pad temperature relating to ambient temperature was developed and it can fully satisfy the safety and the reliability.
In recent years, Ulaanbaatar, a capital of Mongolia has witnessed major problem that air quality reaches hazardous level during the winter season. Coal combustion for heating of every house in "Ger" district is main reason. One way to reduce the air pollution is mass usage of electric heater. However, there are several difficulties such as overload and degradation of transformers and other equipment used in distribution and transmission systems as well as power shortage occurrence in evening peak period due to residential consumption. This study aims to contribute for solving the air pollution and power shortage problem in Mongolia. One possible solution could be distributed generation (DG) with photovoltaic (PV) penetration. In this study, PV with energy storage (ES) hybrid system to reduce peak load is analyzed. We proposed the suitable structure of PV-ES hybrid for Mongolian household, and suggested several operation scenarios. Optimal operation algorithm is carried out based on a comparison aspect from economical, grid impact and PV penetration possibility. The economic analyse shows annual income of 520USD, and has a payback period of 8 years for selected scenario. The proposed PV-ES system structure is verified by experimentation set on the building rooftop in city center. The suggested scenario is planned to apply for system in further research.
