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sustainability Article Energy Saving of Conservation Voltage Reduction Based on Load-Voltage Dependency Ahmet Onen Department of Electrical and Electronic Engineering, Abdullah Gul University, Kayseri 38080, Turkey; [email protected]; Tel.: +90-352-2248800 Academic Editor: Andrew Kusiak Received: 15 July 2016; Accepted: 10 August 2016; Published: 15 August 2016 Abstract: Reducing voltage to reduce energy consumption, referred to as conservation voltage reduction (CVR), can lead to energy savings. Calculating the effects of reducing voltage requires accurate load models. This paper investigates a load-voltage dependency factor that can be measured via field experiments using common existing instrumentation. A relationship between the load-voltage dependency factor and the percentage of the load that is constant impedance and the percentage that is constant power is presented. A new coordinated control algorithm using the load-voltage dependency factor measured by the field experiments is proposed. Parametric studies are presented which compare CVR with coordinated control versus traditional control. Across the two model comparisons of minimizing energy consumption, the coordinated control for conservation voltage reduction showed significant energy reduction over local control. Keywords: voltage dependency; coordinated control; energy reduction; conservation voltage reduction 1. Introduction Many loads consume less energy when operated at a lower voltage. Not all loads exhibit this behavior, but often an aggregate load, such as the load on a distribution feeder, will consume less energy when operated at a lower voltage [1,2]. Lowering voltage to reduce the energy consumed by the aggregate load of a feeder is referred to as conservation voltage reduction, or CVR. The CVR factor for this work is defined as the percentage power flow change that occurs when the supply voltage is lowered by 1%. The ability to accurately estimate the energy saving of CVR versus its cost, and to evaluate control strategies for implementing CVR, depend upon having load models that reflect the real-world, voltage dependency of the aggregate load [3]. Developing such models requires field experiments involving changing the voltage magnitude and measuring the change in load. When voltage control devices exist in a substation, they may be used to raise and lower the voltage in a series of experiments to measure load-voltage dependency. When measuring the effects that voltage changes have on energy consumption, instrumentation often exists for just measuring voltage and current magnitudes, and not for accurately measuring power flows. Such instrumentation can be used to measure the change in current magnitude relative to a change in voltage magnitude, referred to here as the load-voltage dependency factor. The load-voltage dependency factor may be related to other load models, such as loads modeled as a combination of constant power, constant impedance, and constant current. The load models that are used in power system analysis usually consist of constant impedance and constant power loads. In reality these types of loads do not behave the same with respect to voltage on the system [4]. In this paper this load-voltage dependency is taken into account and its effect on a coordinated control algorithm is investigated. Sustainability 2016, 8, 803; doi:10.3390/su8080803 www.mdpi.com/journal/sustainability Sustainability 2016, 8, 803 2 of 11 There are two main types of control in literature, local and coordinated [5,6]. Local controllers include time-controlled capacitors and voltage-controlled capacitors. With technological development, decisions can be made by coordinated control where measurements and model information are used to decide optimum settings for local controllers. Local controllers for switched capacitors, voltage regulators and load tap changers use voltage set points which specify a range for control; the coordinated controller would update the voltage set-points [7,8]. Controllable devices include switched capacitor banks, voltage regulators, load tab changers (LTC) and distributed energy resources (DER) [9,10]. The set points determined by the coordinated controller will, for instance, coordinate a capacitor bank’s operation with other controllable devices on the feeder. The set points to the switched capacitor may change due to a number of conditions such as growth in loading level, reconfiguration of the feeder, and based on different type of loads and their voltage sensitivity. In the literature a number of papers have been written to explain the effects of coordinated control on power systems. Abdel Salam, T.S. et al. [7] describes an algorithm for optimal capacitor placement based on determining nodes whose voltages affect losses in the system the most, but load-voltage dependency factors are not considered. Authors in [11] propose the coordinated control algorithm with two modes; efficiency and CVR, but the authors assumed a load-voltage dependency factor [12] uses coordinated control for reduction of losses and to reduce controller motion, again without considering load-voltage dependency. In [13] the author proposes a coordinated control algorithm to achieve better voltage and operation times of LTC and switched capacitors, but again did not consider load-voltage dependency [14] explores a coordinated control method for load tab changer and switching capacitor to reduce the operation of both devices without considering different types of loads. The work here focuses on a new coordinated control algorithm and uses field measurements of load-voltage dependency factors. Approximately 1200 feeders are evaluated for CVR performance, where 11 feeders were selected for being top CVR performers and used in a pilot study. The feeders considered are divided into two types, short feeders, such as those commonly occurring in urban areas, and longer feeders, such as those commonly occurring in rural areas. This paper is organized as follows: the load-voltage dependency factor is discussed in Section 2; the coordinated control algorithm is introduced in Section 3; a case study and a discussion of the results are provided in Section 4; and, finally, conclusions are given in Section 5. 2. Load-Voltage Dependency Factor Load-voltage dependency here relates percent changes in voltages to percent changes in currents. This representation of load-voltage dependency can be calculated using existing measurements of current magnitude and substation voltage magnitude, which are measurements that exist for many distribution feeders that are instrumented. Table 1 shows some representative load-voltage dependency factors. Table 1. Load-voltage dependency factor for different loads. Load Component (% Change in I)/(% Change in V) Battery Charge Fluorescent Lamps Constant Impedance Air Conditioner Constant Current Pumps, Funs other Motors Small Industrial Motors Constant Power 1.59 1.07 1 −0.5 0 −0.92 −0.9 −1 From Table 1 it may be noted that, for common loads, there can be a significant difference between the load-voltage dependencies. However, many distribution feeders have instrumentation that may Sustainability 2016, 8, 803 3 of 11 Sustainability 2016, 8, 803 3 of 11 be used to determine the load-voltage dependency factor, but are not instrumented so that changes changes in power may be accurately determined. For many existing feeders, measurement of loadin power may be accurately determined. For many existing feeders, measurement of load-voltage voltage dependency at the start of a feeder may be made using existing instrumentation by running dependency at the start of a feeder may be made using existing instrumentation by running many many experiments, where the voltage magnitude at the start of the feeder is stepped up and down, experiments, where the voltage magnitude at the start of the feeder is stepped up and down, and the and the change in current magnitude is measured. Since load-voltage dependency factors vary with change in current magnitude is measured. Since load-voltage dependency factors vary with the load the load mixture, these experiments can be run at different times, such as during the summer and mixture, these experiments can be run at different times, such as during the summer and during the during the winter, to determine time varying values to use for the load-voltage dependency. winter, to determine time varying values to use for the load-voltage dependency. The relation between the load-voltage dependency factors for constant impedance and constant The relation between the load-voltage dependency factors for constant impedance and constant power load models will now be considered and is shown Figure 1. power load models will now be considered and is shown Figure 1. Figure 1. (a) Circuit for for load-voltage dependent load; andand (b) (b) circuit for for constant impedance andand Figure 1. (a) Circuit load-voltage dependent load; circuit constant impedance constant power load. constant power load. Equation (1) (1) relates thethe load-voltage dependency Equation relates load-voltage dependencymodel; model;the theright righthand handside sideof of Equation Equation (1), (1), to to aa load impedance, while thethe leftleft hand side of of loadmodel modelconsisting consistingofofconstant constantpower powerand andconstant constant impedance, while hand side Equation (1) (1) is the load-voltage dependency model: Equation is the load-voltage dependency model: V× f VN IN + VI×=I = V2 V + R (1)(1) where f = fraction of load that is constant power; V = actual voltage magnitude; I = actual current where of load that is constant power; V = actual voltage magnitude; I = actual current f = fraction vN magnitude; V = nominal voltage magnitude; I = nominal current; R = constant impedance = ; N N (1− f ) I magnitude; V = nominal voltage magnitude; I = nominal current; R = constant impedance N 2 N N P = f VN IN = constant power load; VR = constant impedance load; and V × I = voltage dependent = =constant impedance load; and V × I = voltage ; = = constant power load; V 2 (1− f ) I 2 ( ) V V − VN N load. Substituting VR = and I =( IN) + KIN into Equation (1) gives: VN VN dependent load. Substituting = and I = + into Equation (1) gives: (V − V ) V 2 (1 2− f ) IN ) N ) = f VN IN + V (1 f ) I V ( IN + (V NV NKI V ( I N VN K I N ) fV N I N VN VN VN where K = load−voltage dependency where: where K = load−voltage dependency where: V − VN K ∆I = ∆I =VN N (2) (2) If K = 1, then the load becomes a constant impedance load when K = 0, the load becomes a constant If K =When 1, then becomes a constant impedance load when K = 0, the load becomes a current load. K =the −1load the load becomes a constant power load. constant load. When K = −1tothe becomes a constant power load. Let the current actual voltage be related theload nominal voltage by: Let the actual voltage be related to the nominal voltage by: V = hVN (3) (3) V= ℎ Substituting Equation (3) (3) intointo Equation (2),(2), we we obtain K asKaasfunction of hofand f, asf,given by: by: Substituting Equation Equation obtain a function h and as given f − hf h h2 (h12 (1 − f )f ) K= K + h(h −h(1h) 1) h(hh− ( h 1)1) Applying L’Hospital’s rule to Equation (4) for h = 1, we get: (4)(4) Sustainability Sustainability 2016, 2016, 8, 8, 803 803 44 of of 11 11 Applying L’Hospital’s rule to Equation lim(4) for K h 1= 1,2we f get: h 1 (5) limh→1 K = 1 − 2 f (5) Given an experimentally-measured value of K and a value of h, Equations (4) and (5) may be for different seasons used Given to determine the value of f . f values an experimentally-measured value associated of K and a with valueKofvalues h, Equations (4) and (5) mayand be length feeders are plottedassociated in Figure with 2. K values for different seasons and length of used toofdetermine themeasured value of fand . f values feeders are measured and plotted in Figure 2. Figure 2. Variation of load-voltage dependency factor K and fraction f of the load that is under constant Figure dependency factor K and fraction f of the load that is under power 2. as Variation a functionofofload-voltage the season and length of the feeder power load. constant power as a function of the season and length of the feeder power load. Figure 2 illustrates how the load-voltage dependency factor can vary with seasons and length Figure 2 illustrates how the load-voltage dependency factor can vary with seasons and length of of the feeder. The feeders are divided into two types based on length, where short feeders are less the feeder. The feeders are divided into two types based on length, where short feeders are less than than 5 miles long and long feeders are more than 5 miles. Short feeders consist of 60% constant power 5 miles long and long feeders are more than 5 miles. Short feeders consist of 60% constant power (40% constant impedance) during the summer, while during the winter the same feeders behave with (40% constant impedance) during the summer, while during the winter the same feeders behave with 45% constant power (55% constant impedance). The long feeders operate with 55% constant power 45% constant power (55% constant impedance). The long feeders operate with 55% constant power load during the summer and 80% constant power load during the winter. load during the summer and 80% constant power load during the winter. 3. Coordinated Control Algorithm 3. Coordinated Control Algorithm The coordinated control algorithm serves here for minimizing energy delivered by reducing Thewhile coordinated control serves for minimizing energy delivered by reducing voltage maintaining the algorithm voltage within anhere acceptable range. voltage while maintaining the voltage within an acceptable range. The control algorithm first discovers all the controllable devices—switchable capacitors, Theregulators, control algorithm first discovers allfeeders. the controllable devices—switchable voltage voltage load tap changers—in Additionally, the coordinatedcapacitors, control algorithm regulators, load tap changers—in feeders. Additionally, the coordinated control algorithm automatically discovers control devices when they inserted or removed. In addition to this discovery, automatically discovers devices when inserted or removed. addition to this discovery, the coordinated controlcontrol also categorizes thethey control devices as singleInstep or multiple step and the coordinated control also categorizes the control devices as single step or multiple step and determines optimum set points for the local controllers. Single step devices in this study are switched determines optimum set points for the local controllers. Single step devices in this study are switched capacitors since it has just ON or OFF mode. Voltage regulators and load tap changers are multi-step capacitors since it has just ON or OFF mode. Voltage regulators and load tap changers are multi-step control devices, since they have a 16 step size in this study and, based on the required voltage algorithm, control devices, since they have a 16 step size in this study and, based on the required voltage decides which steps are the best choice for voltage interval. algorithm, decides which steps are the best choice for voltage interval. Figure 3 shows how the discovery process of coordinated control works. This discovery needs to Figure 3 shows how the discovery process of coordinated control works. This discovery needs run before the coordinated control runs since the coordinated control needs to know all controllable to run before the coordinated control runs since the coordinated control needs to know all devices and to categorize the control devices. controllable devices and to categorize the control devices. Sustainability 2016, 8, 803 Sustainability 2016, 8, 803 Sustainability 2016, 8, 803 5 of 11 5 of 11 5 of 11 Figure 3.3.Controller discovery and categorization. categorization. Figure3. Controllerdiscovery discoveryand Figure Controller categorization. To be able reachits itsobjective, objective,the thecoordinated coordinatedcontrol controltries tries minimize the customer voltage To be able to reach the coordinated control triestoto tominimize minimize the customer voltage To be able toto reach its objective, the customer voltage while maintaining the customer voltage within the required operating range. Figure 4 shows the while voltage within within the therequired requiredoperating operatingrange. range.Figure Figure 4 shows the whilemaintaining maintaining the the customer customer voltage 4 shows the coordinated control algorithm and illustrates the use of load-voltage dependency factors in the coordinated control algorithm and illustrates the use of load-voltage dependency factors in the coordinated control algorithm and illustrates the use of load-voltage dependency factors in the energy energyreduction reductioncalculation. calculation. energy reduction calculation. Figure4.4.Coordinated Coordinatedcontrol controlalgorithm algorithmwith withload-voltage load-voltagedependency dependencyfactor. factor. Figure Figure 4. Coordinated control algorithm with load-voltage dependency factor. Sustainability 2016, 8, 803 Sustainability 2016, 8, 803 6 of 11 6 of 11 The steps in the algorithm are as follows: Figure 3 to know thethe status of Step 1: Coordinated Coordinated control controlruns runsthe thediscovery discoveryalgorithm algorithmfirst firstfrom from Figure 3 to know status control devices and categorizes thethe control devices. of control devices and categorizes control devices. Step 2: The existing system can be classified as a base case, and then initial voltages and energy delivered are calculated for the base case. Step 3:3:Check whether or not dependency exists, and exit ifand there is no Check whether orload-voltage not load-voltage dependency exists, exit if load-voltage there is no dependency. load-voltage dependency. Step 4: If a voltage-dependent load exists, then use the value from field measurements. measurements. Step 5: Coordinated Coordinated control control applies applies load-voltage load-voltage dependency dependency factors factors to to estimate estimate the energy reduction achieved. Step 6: When the iteration has finished, the coordinated control uses the solution as the starting solution for the next iteration. Step 7: 7: When When the thealgorithm algorithmhas hasfinished, finished,the the optimum local control points minimizing optimum local control setset points for for minimizing the the energy, while maintaining the voltage within the required limits, determined. loadload energy, while maintaining the voltage within the required limits, havehave beenbeen determined. 4. Case CaseStudy: Study:CVR CVRand andEnergy EnergyResults Results 4. In this this section section results results from from aaCVR CVRstudy studyon ona asystem systemconsisting consistingofofmore more than 1200 feeders In than 1200 feeders is is presented. presented. 4.1. Results Results for for the the Entire Entire System System 4.1. Statistical variations variations in in load-voltage load-voltage dependency dependency factors factors and and CVR CVR factors factors for for different Statistical different seasons seasons are shown in Figures 5 and 6. The reason the load-voltage dependency and CVR factors varying for are shown in Figures 5 and 6. The reason the load-voltage dependency and CVR factors varying for different seasons different seasons is is the the change change in in types types of of loads loads used used in in different different seasons. seasons. Summer statistics Wintter statistics 600 400 350 500 300 400 250 300 200 150 200 100 100 0 -0.5 50 0 0.5 1 CVR factor(%) 1.5 0 -0.5 0 0.5 1 CVR factor(%) Figure 5. CVR factors for different seasons. Figure 5. CVR factors for different seasons. 1.5 Sustainability 2016, 8, 803 Sustainability2016, 2016,8,8,803 803 Sustainability 7 of 11 7 7ofof1111 600 600 Summerstatistics statistics Summer 600 600 500 500 500 500 400 400 400 400 300 300 300 300 200 200 200 200 100 100 100 100 0 0-2 -2 00 22 44 voltagedependency dependencyfactor(%) factor(%) voltage Wintterstatistics statistics Wintter 0 0-4 -4 -2-2 00 22 44 voltagedependency dependencyfactor(%) factor(%) voltage Figure 6. Load-voltage dependency factors for different seasons. Figure6.6.Load-voltage Load-voltagedependency dependencyfactors factorsfor fordifferent differentseasons. seasons. Figure Implementing CVR with coordinated control versus implementing CVR with local control ImplementingCVR CVRwith withcoordinated coordinatedcontrol controlversus versusimplementing implementingCVR CVRwith withlocal localcontrol controlisis is Implementing compared next. From Figures 7–10 it may be seen that the load energy is significantly lower with comparednext. next.From FromFigures Figures7–10 7–10ititmay maybe beseen seenthat thatthe theload loadenergy energyisissignificantly significantlylower lowerwith with compared coordinated control. InInFigures 7–10 only feeders that have an energy savings moremore than than 1% with CVR coordinated control. Figures 7–10 only feeders that have an energy savings 1% with coordinated control. In Figures 7–10 only feeders that have an energy savings more than 1% with are considered, whichwhich amounted to 260to feeders. CVR areconsidered, considered, amounted 260feeders. feeders. CVR are which amounted to 260 savingsduring duringthe reduction. Figure7.7.Urban Urbanarea areafeeder’s feeder’ssavings thesummer summerwith withpercentage percentagevoltage voltagereduction. reduction. Figure Figures7–10 7–10 show the percent energy savings with respect percent voltage reduction. Figures savings with respect totopercent voltage reduction. InIn Figures 7–10show showthe thepercent percentenergy energy savings with respect to percent voltage reduction. Figure 7 summer savings are illustrated for the urban area’s feeders while Figure 8 shows winter Figure 7 summer savings areare illustrated forfor thethe urban area’s feeders In Figure 7 summer savings illustrated urban area’s feederswhile whileFigure Figure8 8shows showswinter winter savingsfor forthe theurban urbanarea’s area’sfeeders. feeders.For Forurban urbanarea’s area’sfeeders feedersduring duringthe thesummer summerthe theload-voltage load-voltage savings savings for the urban area’s feeders. For urban area’s feeders during the summer the load-voltage dependencyfactor factor −0.2%, which means thethe system consists 60% constant power loadand and40% 40% dependency which means the system consists ofof60% constant power load dependency factorisis is−0.2%, −0.2%, which means system consists of 60% constant power load and constant impedance load. Average customer energy savings for the urban area’s feeders during the constant impedance load. load. Average customer energy savings for the area’sarea’s feeders during the 40% constant impedance Average customer energy savings forurban the urban feeders during summer is around 2.5%. summer is around 2.5%.2.5%. the summer is around Sustainability 2016, 8, 803 Sustainability 2016, 2016, 8, 8, 803 803 Sustainability 8 of 11 of 11 11 88 of Figure 8. Urban area feeder’s savings during the winter with percentage voltage reduction. Figure 8. Urban area feeder’s savings during the winter with percentage voltage reduction. Figure 8. Urban area feeder’s savings during the winter with percentage voltage reduction. Figure 8 looks at the urban area’s feeders during the winter time where the load-voltage Figurefactor looks at the thewhich urbanmeans area’sthe feeders during theofwinter winter time where where the load-voltage dependency is 0.1%, systemduring consists 45% constant powerthe load and 55% Figure 88 looks at urban area’s feeders the time load-voltage dependency factor is 0.1%, which means the system consists of 45% constant power load andthe 55% constant impedance Average customer urban area’s power feedersload during dependency factor isload. 0.1%, which means the energy system savings consists for of 45% constant and 55% constant impedance customer energy savings for urban area’sarea’s feeders duringduring the winter winter time is around load. 3.3%. constant impedance load.Average Average customer energy savings for urban feeders the time is around 3.3%. winter time is around 3.3%. Figure 9. Rural areas feeder’s savings during the summer with percentage voltage reduction. Figure 9. Rural areas feeder’s savings during the summer with percentage voltage reduction. Figure 9. Rural areas feeder’s savings during the summer with percentage voltage reduction. Figure9 looks 9 looks the rural area’s feeders during summer, where the load-voltage dependency Figure atat the rural area’s feeders during thethe summer, where the load-voltage dependency factorisisaround around0.1%, 0.1%,which whichmeans meansthat thatthe thesystem systemconsists consistsofof55% 55%constant constantpower powerload loadand and45% 45% factor Figure 9 looks at the rural area’s feeders during the summer, where the load-voltage dependency constant impedance load. The average customer energy savings for rural area’s feeders during the constant load. The average customer energy savings rural area’spower feedersload during factor isimpedance around 0.1%, which means that the system consists of for 55% constant and the 45% summer time is around 2.8%. summer is around 2.8%. constanttime impedance load. The average customer energy savings for rural area’s feeders during the summer time is around 2.8%. Sustainability2016, 2016,8,8,803 803 Sustainability 9 of 9 of 1111 Figure 10. Rural area feeder’s savings during the winter with percentage voltage reduction. Figure 10. Rural area feeder’s savings during the winter with percentage voltage reduction. Figure1010the therural ruralarea’s area’sfeeders feedersduring duringthe thewinter winterare areconsidered, considered,where wherethe theload-voltage load-voltage InInFigure dependencyfactor factorisis0.57%, 0.57%,which whichmeans meansthat thatthe thesystem systemconsists consistsofof78.5% 78.5%constant constantpower powerload loadand and dependency 11.5%constant constantimpedance impedanceload. load.The Theaverage averagecustomer customerenergy energysavings savingsfor forrural ruralarea’s area’sfeeder feederduring during 11.5% thewinter winterisisaround around3%. 3%. the 4.2.Results Resultsforfor1111Feeders Feeders 4.2. Ofthe the260 260feeders feedersconsidered consideredininSection Section4.1, 4.1,the the1111feeders feedersthat thathad hadthe thebest bestCVR CVRperformance performance Of were identified. It should be noted that these top performing feeders all had a relatively flatvoltage voltage were identified. It should be noted that these top performing feeders all had a relatively flat profile.Table Table2 2shows showsthe theload-voltage load-voltagedependency dependencyfactors factorsfor forthese thesefeeders feeders for the different seasons. profile. for the different seasons. As can see from the table, during the summer the load-voltage dependency factors are higher than As can see from the table, during the summer the load-voltage dependency factors are higher than during the winter. during the winter. Table2.2.Load-voltage Load-voltagedependency dependencyfactor factorfor fortop topperforming performingfeeders. feeders. Table Feeder Feeder No. No. 1 1 22 33 4 5 66 7 7 8 89 9 10 10 11 11 Load-VoltageDependency DependencyFactor Factor Load-Voltage Summer Winter Summer Winter −0.051 −0.051 −0.049 −0.049 0.000 0.000 −0.131 −0.131 −0.055 −0.055 −0.064 −0.064 −0.036 −0.036 −0.058 −0.058 −0.025 −0.025 −0.057 −0.057 −0.106 −0.106 0.007 0.007 0.049 0.049 0.000 0.000 −−0.008 0.008 −−0.018 0.018 0.020 0.020 0.069 0.069 0.057 0.057 0.087 −0.087 0.030 −−0.030 0.246 −0.246 Using the load-voltage dependency factors, the coordinated control was used to analyze the Using the load-voltage dependency factors, the coordinated control was used to analyze the 11 11 feeders every hour for an entire year (8760 time points). Figure 11 compares the power savings of feeders every hour for an entire year (8760 time points). Figure 11 compares the power savings of coordinated control with the power savings of local control. coordinated control with the power savings of local control. Sustainability Sustainability2016, 2016,8,8,803 803 10 10of of11 11 Figure coordinated control control power power savings savingsfor for11 11top topperforming performingfeeders feedersasasa Figure 11. 11. Local Local control control versus versus coordinated afunction functionofofhour hourofofthe theyear. year. Based 11,11, savings from the coordinated control is 2–3istimes (around(around 10 GWhr) Basedon onthe theFigure Figure savings from the coordinated control 2–3 greater times greater 10 than thethan localthe control savings.savings. The savings changechange throughout the year based on demand. It is GWhr) local control The savings throughout theisyear is based on demand. interesting to note that the the demand, the greater the savings. It is interesting to note thatlarger the larger the demand, the greater the savings. 5. Conclusions 5. Conclusions Load-voltage cancan be measured experimentally on many existing Load-voltagedependency dependencyfactors factors be measured experimentally on feeders many with feeders with measurement devices. devices. With respect to load-voltage dependency factors,factors, load combinations were existing measurement With respect to load-voltage dependency load combinations determined which which were equivalent to the load-voltage dependency factors. factors. A new coordinated control were determined were equivalent to the load-voltage dependency A new coordinated algorithm that made use of load-voltage dependency factors was described. control algorithm that made use of load-voltage dependency factors was described. Two models were compared based on the reduction of energy. The Two models were compared based on the reduction of energy. Thefirst firstmodel modelinvolved involved feeders feeders with local control and the second model involved feeders with coordinated control. The results with local control and the second model involved feeders with coordinated control. Theshowed results that coordinated control with conversation voltage reduction helps to reduce energythe delivered. showed that coordinated control with conversation voltage reduction helps the to reduce energy Results presented information about energyabout reduction forreduction different load-voltage dependency delivered. Resultsprovide presented provide information energy for different load-voltage factors. Across the two model comparisons of minimizing energy consumption, the coordinated dependency factors. Across the two model comparisons of minimizing energy consumption, the control for conversation reduction showed significant energy reductionenergy over local control. coordinated control for voltage conversation voltage reduction showed significant reduction over local control. Acknowledgments: The work is supported by the project “Rastgele Yük Eğrisi metodu ile elektrik kayıplarının hesaplanması” funded bywork national institute AGU project BAP with project ID 48.ile elektrik kayıplarının Acknowledgments: The is supported by thewith project “Rastgele Yükthe Eğrisi metodu hesaplanması” funded by national institute AGU with project BAP with the project ID 48. Conflicts of Interest: The authors declare no conflict of interest. Conflicts of Interest: The authors declare no conflict of interest. References References 1. Ahmet, O. Model-Based Grid Modernization Economic Evaluation Framework. Ph.D. Thesis, Virginia Institute and State Blacksburg, VA, Evaluation USA, MarchFramework. 2014. 1. Polytechnic Ahmet, O. Model-Based GridUniversity, Modernization Economic Ph.D. Thesis, Virginia 2. Gönen, T. Electric Power Distribution System Engineering, 2nd ed.; CRC Press: Boca Raton, FL, USA, 2008. 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