• Proceedings of the KIEE Conference
• /
• 1996.07b
• /
• pp.778-780
• /
• 1996

The predictive maximum demand controllers often bring about large number of control actions during the every integrating period and/or undesirable load-disconnecting operations during the begining stage if the integrating period. To solve these problems, a fuzzy predictive maximum demand control algorithm is proposed, which determines the sensitivity if control action by urgency if the load interrupting action along with the predicted demand reading to the target or the time arriving at the end stage if the integrating period. A prototype controller employing the proposed algorithm also is developed and its performances are tested by PROCOM SYSTEMS Corperation of Korea.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.34 no.10
• /
• pp.389-398
• /
• 1985

Recently maximum power demand of our country has become to be under the great in fluence of electric cooling and air conditioning demand which are sensitive to weather conditions. This paper presents the technique and algorithm to forecast the long-term maximum power demand considering the characteristics of electric power and weather variable. By introducing a weather load model for forecasting long-term maximum power demand with the recent statistic data of power demand, annual maximum power demand is separated into two parts such as the base load component, affected little by weather, and the weather sensitive load component by means of multi-regression analysis method. And we derive the growth trend regression equations of above two components and their individual coefficients, the maximum power demand of each forecasting year can be forecasted with the sum of above two components. In this case we use the coincident dry bulb temperature as the weather variable at the occurence of one-day maximum power demand. As the growth trend regression equation we choose an exponential trend curve for the base load component, and real quadratic curve for the weather sensitive load component. The validity of the forecasting technique and algorithm proposed in this paper is proved by the case study for the present Korean power system.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.66 no.1
• /
• pp.7-14
• /
• 2017

Recently, the power consumption of industrial consumer has increased rapidly, causing problems such as lack of power reserve margin in summer and winter, and therefore there is a growing need for maximum demand power management to consumers. In this paper, we studied small microgrid system consisting of battery ESS and photovoltaic power system, applied to small and medium sized factories to reduce the maximum demand power of daily industrial power load. To verify the validity of the study, we simulated a small microgrid system using Matlab/Simulink software. As a result of applying the simulation to small and medium sized plants that consume a lot of power, it is confirmed that there is a 13% reduction in demand compared to the existing maximum demand power. This result is expected to contribute to the improvement of the power reserve margin.

• The Korean Journal of Emergency Medical Services
• /
• v.6 no.1
• /
• pp.77-86
• /
• 2002

The purposes of this research which was conducted by surveying lost/added unit hours reports, unit hour demand analysis worksheets from prehospital care reports of two squads in Kyonggi Provincial Fire and Disaster Headquarters for 20 weeks (January 1, 2002 - May 20, 2002) are to get Unit Hour Utilizations. Call Demands such as Unit Hour Demand, Simple Average Demand, High Average Demand, Peak Average Demand, the High Actual Demand. The conclusions from this analysis were summarized as follows: (1) By revealing Unit Hour Produced 3223.9, Call Volume 964, Unit Hour Utilization 0.299 at the Squad A and Unit Hour Produced 3328.4, Call Volume 901, Unit Hour Utilization 0.271 at the Squad B induced Korean Squads to chance identification, definition, direction of Unit Hour Utilization. (2) By revealing Simple Average Demand 7.4 on Monday Tuesday, High Average Demand 9.6 on Tuesday Friday. Peak Average Demand 11.5 on Tuesday, the High Actual Demand 12 on Tuesday Wednesday at the Squad A and Simple Average Demand 6.8 on Sunday, High Average Demand 10.4 on Monday, Peak Average Demand 11.5 on Monday, the High Actual Demand 13 on Monday at the Squad B enabled Korean Squads to utilize System Status Management. (3) The Maximum Calls per Unit Hour were 115 for 23:00~23:59, the Minimum Calls per Unit Hour were 46 for 05:00~05:49 in two squads. The Maximum Calls per Unit Hour were 7.4 on Tuesday Saturday, the Minimum Calls per Unit Hour were 6.1 on Thursday at the Squad A. The Maximum Calls per Unit Hour were 7.3 on Monday Saturday, the Minimum Calls per Unit Hour were 5.6 on Thursday at the Squad B. (4) Analyzing demand for EMTs in the optimum emergency medical service of Korea, we have been able to utilize this Unit Hour Utilization in company with the established estimation methods such as international comparisons or the number of ambulances for scientific reasonable estimation. (5) These Call Demands which were limited to the demand time in this study will make us expect some following studies including demand time, demand time, demand map for Strategic Deployment.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.63 no.3
• /
• pp.75-85
• /
• 2021

This study evaluated variations in the paddy rice water demand based on the continuous changing in rice transplanting period and ponding depth at the four study paddy fields, which represent typical rice producing regions in Korea. Total 7 scenarios on rice transplanting periods were applied while minimum ponding depth of 0 and 20 mm were applied in accordance with maximum ponding depth ranging from 40 mm to 100 mm with 20 mm interval. The weather data from 2013 to 2019 was also considered. The results indicated that the highest rice water demand occurred at high temperature and low rainfall region. Increased rice transplanting periods showed higher rice water demand. The rice water demand for 51 transplanting days closely matched with the actual irrigation water supply. In case of ponding depth, the results showed that the minimum ponding depth had a proportional relationship with rice water demand, while maximum ponding depth showed the contrary results. Minimum ponding depth had a greater impact on rice water demand than the maximum ponding depth. Therefore, these results suggest that increasing the rice transplanting period, which reflects the current practice is desirable for a reliable estimation of rice water demand.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.3
• /
• pp.95-99
• /
• 2013

The maximum power analysis simulator took advantage of the facilities and power consumption reduction simulator test scenario development and testing of improvement in the scenario. As a maximum demand power controller, Maximum power analysis simulator performs control and disperasion of maximum demand power by calculating base power, load forecast, and present power which are based on signal of watt-hour meter to keep the electricity under the target. In addition, various algorithms to select appropriate control methode on each of the light installations through the peak demand power is configured to management. The simulation shows the success of control power for the specified target controlled by five sequential lighting installations.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.1067-1070
• /
• 2002

The maximum demand power management system(the demand controller) is an equipment for demand management. If the pre-estimated load is over the preset power, the demand controller make warnings and break the load circuit according to predefined priority. Then consumption power is maintained below the maximum demand power level. The DTU receives the control commands from demand controller, and then controls loads. In this paper, the power line cables are used for communication between the demand controller and DTUs and monitoring PC. The experiments show that the proposed system is compatible with the conventional system, and feasible for new or remodeling plant.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.10
• /
• pp.963-968
• /
• 2016

This paper proposes a new method reducing the maximum demand power of substations at urban railway by using transformer with OLTC(:On Load Tap Changer). Most of the domestic urban railway is rectified by a diode scheme, and supplies the electric vehicles in dc 1500[v]. Because the substations are connected in parallel, if an input voltage of a substation is increased, then the voltage of rectifiers is also increased, and which leads to an increase in the maximum demand of the substation. Simulation results show that increment of maximum demand power can significantly be limited using the method proposed in this paper.

• Journal of Korean Society of Water and Wastewater
• /
• v.8 no.2
• /
• pp.35-42
• /
• 1994

This study is to analyse probability distribution characteristics of water supply demand. Two cities located near Seoul were selected as study areas. In this study, two probalility distribution types were tested using the K-S(Kolmogorov-Smirnov) method. The K-S method was used to prove the goodness of the selected distribution type. And also, the goodness of maximum day demand to average day demand ratio which was obtained by field data was tested. Conclusions are as follows. 1.Bothl normal distribution type and lognormal distribution type are appropriate as the probalility distribution type for the water supply demand. 2. The probability distribution characteristics can be used to test the goodness of the maximum day to average day demand ratio.

• Journal of the Korean Professional Engineers Association
• /
• v.44 no.2
• /
• pp.29-33
• /
• 2011

In recent years, maximum electric power demand has been increasing steadily. But, Electric Power Supply & Demand problem is occurring due to lack of electric power reserve ratio caused by electric power peak. For this reason, I investigated the current status of the Electric Power Supply & Demand and established Electric Power Supply & Demand and established Electric Power Supply & Demand measures. I will expect that this paper will be contributed balanced and stable Electric Power Supply & Demand management.