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TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

Hybrid Socio-Technical & Economic Interaction Networks Application: the Theoretical Cost of Penalties for Non-Delivery of Power Energy

Sorina Costinaș 1, Ioana Opriș 1, Daniela Elena Gogoaşe Nistoran 1, Ion Triștiu 1, Cristina Sorana Ionescu 1

1 University POLITEHNICA of Bucharest, Splaiul Independenței 313, Bucharest, Romania

Abstract – The protection of critical controllability, maintenance, reduced operating costs, is essential to the future sustainability of addressing of the increasing expectations of systems. The resilience at the smart meters type threats customers regarding an affordable and reliable requires an integrated interdisciplinary approach of electric service. the technical and the social components of smart substation. The manner in which the decisions The implementation of new within regarding the designing of the electrical substations for power systems is changing the image that we have on the evacuation of the produced in a the configuration of the and the power plant is analyzed and proposed the cost of elements that can be integrated into it [2]. It is penalties calculation methodology for nondelivery of necessary to asses the new functionalities that are power energy from the point of view of socio-technical included into the next generation digital substations, services. so as to guarantee cost-effective, high functionality Keywords – Cost of penalties, Decision, Electrical and future proofed automation of the end-to-end grid substation, Scheme, Socio-tehnical system. [3].

When increasing the number of intelligent 1. Introduction electronic devices in a substation, the overall

An represents a node within a substation´s reliability is reduced. Each new added grid to which are connected several elements: element has a direct impact on the mean operation generators, electrical lines, power etc. time between failures of the substation. Therefore, In [1] there are highlighted the performance criteria the vital redundancy level has to be considered in the for substations of the XXI century: reliability, network reconfiguration. security, interoperatibility, low impact on the The world in which we live is a complex, large- environment, flexibility, reconfigurability, scale, interconnected, open and sociotechnical world [4]. From the point of view of the sociotechnical systems, an electrical substation is a dynamic system, DOI: 10.18421/TEM71-09 which involves both social and technical aspects, https://dx.doi.org/10.18421/TEM71-09 being characterized by inputs and outputs from at to other processes. The identification of evaluation Sorina Costinaș, Corresponding author: criteria for the social aspects of the technical system University POLITEHNICA of Bucharest,Bucharest, Romania [5, 6] proved to be a difficult task. STIN models Email: [email protected] approach such sociotechnical interaction network [7]. Received: 27 November 2017. The most important parts of the electrical substations Accepted: 30 January 2018. considered for the evacuation of the electrical energy Published: 23 February 2018. produced in a power plant are:

© 2018 Sorina Costinaș et al; published by • cybersecurity: protecting the grid and UIKTEN. This work is licensed under the Creative several points of access in the system from cyber Commons Attribution-NonCommercial-NoDerivs 3.0 attacks who compromise the critical information; License.

The article is published with Open Access at www.temjournal.com

74 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

• resilience with DERs (resistance at disturbances): section 5, we applied the proposed algorithm for a diversity, redundance of the information, hypothetical but still semi-realistic study case modularity, autonomy; (400/110 kV substation). Section 6 reports the conclusions and possible future research. • reliability in functioning: it functions even in the case of disability of some of the components, it can be physically, communicationally and socially 2. Problem definition & clarification of the scope analyzed; • distributed vs centralized control: territorial We intend to analyse the manner in which the dispatcher centre and national energy dispatcher decisions regarding the designing of the electrical centre; substations were connected to one power plant with nG generator groups, each are with apparent power • autonomy and mastering: detectors, decisions, SnG taken, from the point of view of socio-technical operators, control. services of . • ability to accommodate system changes. The electrical energy produced in power plants of A series of basic information is known, such as: different types (e.g. power plants, gas power the profile and emplacement of the substation, the plants, hydro power plants, plants, solar level of pollution, meteorological information, data arrays), each consisting of one or more electricity concerning the planning of investition, elaborating generation units, will be evacuated via two electrical the projects, etc. It is required to cover a series of substations, with the U1, respectively U2 decisions regarding the choice of a solution for the (Figure 2): at consumers with the apparent power substations’ diagrams of connections. Figure 1 SC1, SC2 and in the power system (SS1, SS2). A illustrates the main steps in the rational decision scheme includes transformers/ autotransformers to making model in socio-technical systems and the change voltage levels between U1 and links between them. voltages U2.

Definition of the problem & clarification of the scope

Drawing up a list of technical solutions & sorting solutions based on restrictions

Identify the decision criteria

Select the best solution

Monitoring and evaluation of results Figure 2. Block diagram (technical perspective) for the evacuation of the electrical energy produced in a power plant with nG generators. Figure1. Main steps in the rational decision making model in socio-technical systems. We will take into consideration:

The paper is organized as follows. Section 2 • Technical standpoint: nominal voltage, the offer defines the problem, clarifies the purpose and of major equipment and devices producers [1, 2] identifies the main technical, economical and social technological power and energy losses in aspects for assessing the substation scheme. Section transformers or autotransformers [8], new 3 presents the possible solutions and restrictions for maintenance strategies [9], operation procedures the switching scheme of connections for the high [10, 11], hybrid [12], voltage substations from a technical point of view real-time monitoring, control and analytics within and agrees the criteria of decision. Section 4 is dynamic [3], data acquisition method, devoted to a calculation algorithm for theoretical cost SCADA and packet telecoms domains [4, 13], key of penalties for non-delivery of power energy, from automation technologies and architectures in the the point of view of socio-technical services. In substation automation [11, 14] etc.

TEM Journal – Volume 7 / Number 1 / 2018. 75 TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

• Economical standpoint: investment costs for the The types of schema of connections are specific to electrical installations, the costs of power and the voltage level that they are chosen for. energy losses in transformers and auto- transformers, penalties for nondelivering the The following considerations could be highlighted: electrical energy and compensation for failure to • accept contracted energy, maintenance costs [9, 12, Ring (polygonal) schemes are specific only 15], facilitate future expansion, understand where for 220-750kV substations, which have a reduced budgets are being focused and resource is being number of circuits due to the field-location and the allocated to drive the practical implementation of difficulties of building the systems of protection by the smart grid [14, 16, 17]. relays; • At high voltage, the simple solution (1BC) is taken • Standpoints concerning the regulatory and into consideration if: the number of circuits is social consequences of a potential non-delivery of power energy: market models for smart utilities small, the power transit is reduced, the equipment [4] and the digital transformation [13], the impact is very reliable; the consumers are not very on the quality of electrical energy [15], damage on sensitive to disruptions or there is another line to the environment [18], injuries or loss of life [19, supply it; 20], any constraints imposed of site characteristics • At medium voltage or for indoor substations with [21], consumers [22], producers, prosumers and U ≤ 110kV, we do not choose solutions with the implications of new European regulation [23] transfer busbar (because the space is limited by the and the strategic plans and priorities of electric disposition in the building). utilities for cascade effects that can affect the electrical grid [24], etc. In case there are suggested solutions of schemes of connections that differ from 1 BC, we keep in mind those new circuits which are present in the scheme: 3. Selection of Switching Scheme the transversal coupler, the longitudinal coupler, the bypass coupler, the coupler with multiple functions 3.1 The possible solutions and restrictions. etc. (the type and number of the coupler circuits Technical point of view depend on the type of the suggested scheme).

The single-line diagram for electrical substations 3.2. The decision criteria for selecting the best are independent, so the decision of the optimal solutions. Techico-economical point of view schema is taken separately for each of the substations In order to rank the possible solutions, we suggest with the voltages U1 and U2 (expressed in kV). the minimisation of the present total discount cost For the beginning, we mention the type and the criteria. number of circuits from an electrical substation: The overall calculation formula for the present generator circuits/ generator- block total discount cost (PDTC) is: circuits, circuits of link transformers, consumer line circuit (overhead line or underground cables), system = + + + line circuits. + (1) 푃푇퐷퐶 퐶퐼 �퐶푂푀푀푦푒푎푟 퐶∆푃퐸푇푦푒푎푟 Determining the number of the line circuits that are where: is퐶푃 the푦푒푎푟 invest� ∙ 푇푠푡ment cost, is the connected in a substation is made by long-term annual operation, monitoring and maintenance cost; loading of these electrical lines: the maximum 푂푀푀푦푒푎푟 퐶퐼R is annual cost of power and퐶 energy losses electric load for longer time duration (S ), the M in the link tranformers or autotransformers between number of charged zones and the allowable load on a ∆푃퐸푇푦푒푎푟 퐶the substations with the voltages U and U ; single circuit, depending on the cross section of the 1 2 represents the annual cost of the penalties for non- wires. 푦푒푎푟 delivery of power energy to the consumer areas퐶푃; The usual schema of connections for substations is the value for discounted costs calculation. that can be taken into account for preparing the 푇푠푡 solution lists are: single busbar collector (1BC), The investment costs. The investment costs are single sectionalized busbar collector (1BCS), double equal to the sum of the costs of all the cells that make bus and one breaker (2BC), main busbar collector up a substation and they can be determined according to the producers’ offer. (Table 1). and transfer busbar (1BC+BT), double busbar collector and transfer busbar (2 BC+BT), ring busbar The investment cost (CI) is the purchase price (preferable 4-6 sides), type H schema, etc. [9]. added to the installation cost, expressed in euros [€].

76 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

The costs of operation, monitoring and 12 maintenance. The annual operation, monitoring and maintenance cost (COMMyear), expressed in 10

[€/year], can be determined with: 8 10 years COMM = p∙CI (2) 6 where p is the coefficient for OMM cost, function 15 years

Ttst [years] 4 of the voltage level [%/year]. 20 years 2 For example, the operating data collected for 110kV substations indicates a ratio of about 3.3% 0 between investment costs and operating, monitoring 8 10 12 15 and maintenance costs. This percentage decreases as a [%/year] the voltage of substation increases. Table 1. Switching scheme cost comparation [17], Figure3. The value Tst according to discount rate for if power transformer cost are not included. three-periods of study (ts = 10, 15, 20 years).

Approx. Cost The value Tst for discounted costs calculation. Switching Scheme Comparation The value Tst for discounted costs calculation is defined in [9] and shown in figure 3 for three period Single Busbar Collector 100% of study: Ring Bus (Polygon) 114% ts 1 = (4) Tst ∑ j , Single Sectionalized Busbar 122% j=1 (1 + a) Main and Transfer Busbar 143% where j represents the current year, ts represents Breaker and a Half 156% periods of study, and a is the discount rate, expressed in %/year. The analysis is done for a substation Double Breaker, Double Bus 214% (electrical node). The power and energy losses are basically The cost of power losses and energy losses in produced only in the area of the busbar collector; the transformers. The annual cost of power and energy value of the costs regarding these losses is very low losses in transformers, expressed in [€/year], can be compared to the other categories of costs, so the determined with [8]: differences among the various suggested solutions will not influence their ranking. = + + Therefore, the cost of power and energy losses in 푝 푐 transformers or autotransformers CPEyear can be 퐶∆푃퐸푇푦푒푎푟 푃0 ∙ � 푐푒 ∙ 푡0� + 푇푁푂푇 + (3) disregarded. 2 푆푀 푐푝 푆퐶 2 푝 The simplified calculation formula (1) is: where: is푃 the∙ 푆푟푇power∙ �푇푁푂푇 losses푐 in∙ 휏 �the core of the transformer; is the power losses in the windings 0 of the transformer;푃 is the normal operation time = + + (5) 푆퐶 (for amortization)푃 [years]; is the cost for 1kW 푂푀푀푦푒푎푟 푦푒푎푟 푠푡 푁푂푇 푃푇퐷퐶 퐶퐼 �퐶 퐶푃 � ∙ 푇 installed [€/kW]; 푇 is the unit cost of generating a 푐푝 The optimal solution is considered to be the kWh of electric energy [€/kWh]; τ represents the solution with the minimum present total discount 푐푒 time used to determine the energy losses, with the cost. The results are systematized in a result table operation time to (maximum 8760h/year); like Table 2, in which are specified all component 푆푀 costs in order to highlight the cost categories that represents the transformer flow-ratio for annual 푆푟푇 favoured the optimal solution. maximum load.

TEM Journal – Volume 7 / Number 1 / 2018. 77 TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

Table 2. The centralization of the results

Switching Scheme Solutions 1BC 2BC … … 11% 3%

3 CI [10 €] 15% 40%

3 COMMyearxTst [10 €] 31%

3 PyearxTs [10 €]

3 PTDC [10 €] Weather events and fire Equipment failures For small differences (<5-10%) among the first Insufficient generation solutions in the hierarchy, the selection of substation switching scheme is the results of many aspects, Human errors including intangibles as personal preference, Sabotages experience and judgment. Figure 4. Major Outage Events with Loss of Electric Service, adapted from [23]. 4. Proposing a calculation algorithm for the cost of penalties for non-delivery of power energy. Coupled with the fact that most transmission and Socio-technical point of view distribution (T&D) lines in service today were constructed during the 1960s and 1970s and were not originally engineered to meet today’s demand or At the core of all electricity services is electrical withstand severe weather raises concerns of energy. Power systems are becoming increasingly congestion, distribution, reliability, and cost of integrated with other key sectors and critical service outages due to aging coupled infrastructure [24, 26, 27]. with severe weather can be a massive expense for the Usually, in substations various types of utilities. components are interconnected, such as: high voltage Predictive reliability level is determined by the buses and structures, power transformer (or frequency of interruptions in the past and by the level autotransformer), power lines, , of socioeconomic development and social welfare. voltage transformer, , , disconnect , control building, security Penalties for non-delivery of power energy can barrier, protective relays and SCADA systems, imply a great range of values depending on the grounding systems, protocols relative importance (Figure 5): (a) type of consumer, (substation IT architecture standards, including such as industrial, commercial, residential and IEC61850) and optical sensors. For each of them the contracts; (b) , infrastructure, operational fault rate may vary [10, 25]. processes, procedures and interruption characteristics (such as interval, extent, advance notification or not, Weather events and fire are the leading cause of time of occurrence, etc); (c) weather events (snow/ice power outages [22, 28] (Figure 4). storms, hurricanes, floods etc.).

78 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

Human Factors who use and interact with substations/ Objective/ Contracts

Technology/ Weather Events Infrastructure/ Operational Figure 6. Demarcation example of the two zones of a cell Processes/ Procedures (in switching scheme solutions with 2BC+BT) for the calculation the penalties for non-delivery of power energy.

The modification of penalties for the non-delivery Figure 5. The socio-technical perspective for multi-level of power energy (as a consequence of the interactions an electrical substation process modification of the schema of connections) is thereby produced: practising the bypassing leads to We calculate: cost of the penalties caused by reducing the non-delivery of power energy in the unplanned disconnections (Pyear-unpl) and by planned cells zone; practising a large number of disconnections (Pyear-pl). collector sections leads to reduced non-delivery of power energy in the BC zone. From the point of view of disconnections, the analysis of no electricity supply can be divided in The general formula of calculation to annual two zones. These zones are demarcated according to penalties for the non-delivery of power energy, figure 6, on this showing: expressed in €/year, is:

• The zone of busbar collector zone (symbolized by 1 (6) the superior index ): any disconnection in the BC =

zone determines the indisponibility of the whole 푦푒푎푟 푚푒푑 푛표푛−푑푒푙푖푣푒푟푦 푛표푛−푑푒푙푖푣푒푟푦 푠푝 node (BC); accordingly, we will mark the afferent 푃The calculation푆 is made in∙ 푡 a distinct manner,∙ 푑 for disservices with P(1); the BC zone and for the cells zone and is expressed in €/year. Further, it is necessary to impose several • The cells zone (symbolized by the superior specifications concerning the calculation of the terms index 2): any disconnection in the zone of a cell from (6) relation. determines the indisponibility just of that circuit; accordingly, we will mark the afferent disservices 4.1 The Non-Delivery Electrical Power with P(2). The medium nondelivered power, expressed in For the calculation of the cost of penalties for non- MVA, depends on the maximum electric load for delivery of power energy, there can be made some longer time duration and maximum usage time per simplifying hypotheses, which allow a more rapid year: estimation of them, without affecting the credibility of the obtained solutions: = (7) 8760 푆푀 푛표푛−푑푒푙푖푣푒푟푦 ∙ 푇푆푀 − In the case of planned disconnections, all the cells 푚푒푑 푛표푛−푑푒푙푖푣푒푟푦 The푆 energy transit differs, depending on the location of a substation will be repaired one at a time (there where the nondelivery is calculated (the busbar are not considered more working teams collector zone or the cells zone). simultaneously); Depending on the type of disconnection, these − In the case of disconnections in substations values can modify, thus: for unplanned disconnections equipped with couplers (longitudinals, it is working with Smed non-delivery; for planned transversals, bypassing or with multiple functions), disconnections there can be done the hypothesis of the maneuvre and separation /elimination time of dealing with the consumers (Smed non-delivery can be an incident can be approximatively 2 considered 30-40% of the previous value). hours/disconnection.

TEM Journal – Volume 7 / Number 1 / 2018. 79 TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

( ) 4.2. The Non-Delivery Time = (12) 2 In general, the nondelivery time, expressed in 푡푢푛푝푙( ) ∑ 푡푢푛푝푙 푒푙푒푚푒푛푡푠 €/year, can be estimated with the following relation: = (13) 2 푝푙 푝푙 푒푙푒푚푒푛푡푠 = (8) Under푡 ∑the푡 hypothesis of reviewing the circuits simultaneously with the cell, we will have: in which: 푡λ푛표푛 - the−푑푒푙푖푣푒푟푦 intensity 휆of∙ damage푡푖푛푡푟 or the medium ( ) number of defects in a year [disconnections/year]; tintr = 0 (14) – the medium duration for a disconnection, expressed 2 in hours/disconnection. 4.3.푡푝푙 The specific disservice in electric service

For a solution different from 1BC, can be the The specific disservice ( ) can be expressed in maneuver time. The relation is identical for planned relation to the cost of energy ( ): for unplanned 푖푛푡푟 푠푝 disconnections and for unplanned disconnections.푡 disconnections: is a multiple푑 of ; for planned 푒 disconnections: can be chosen푐 as a lower value The durations are calculated separately, for the 푠푝 푒 (for example, in푑 percentage value,푐 25% of the busbar collector zone and for the cells zone, taking 푠푝 previous value). 푑 into account the following indications. The values of specific disservice produced by no 4.2.1. The Non-Delivery Time in case of supply differ for: the nondelivery in the system inavailability in the busbar collector zone ( = ) and for the nondelivery to the consumer (multiple for the cost of energy, depends the We determine the number of busbar collector steps 푠푝 푒 ( ) and the number of disconnectors ( ), for designing푑 푐 hypotheses). which we have: 푛퐵퐶 푛퐷 4.4. Penalties for Non-Delivery of Power Energy = (9) 4.4.1. Annual Penalties for Non-Delivery of Power Energy in case of inavailability in busbar Whichever BC steps푛퐵퐶 and푛퐷 whichever disconnectors collector zone, [€/year] from the busbar collector can become inavailable during the exploitation, so the respective unitary ( ) ( ) = durations must be summed for determining the total 1 1 duration of nondelivery in the busbar collector zone, 푃 푦푒푎푟 − 푝푙 ∑ 푆 푚푒푑 푛표푛 − 푑푒푙푖푣푒푟푦 푝푙 ∙ 푡 푝푙 ∙ 푑 푠푝 (15) for the two categories of disconnections expressed in hours/year and BC zone: ( ) = 1 ( ) ( ) = + (16) (10) 푃푦푒푎푟−푢푛푝푙 ∑ 푆푚푒푑 푛표푛−푑푒푙푖푣푒푟푦 푢푛푝푙 ∙ 1 1

푡푢푛푝푙 (푛퐵퐶) ∙ 푡푢푛푝푙퐵퐶 푛퐷 ∙ 푡푢푛푝푙퐷 ∙ 푡푢푛푝푙 ∙ 푑푠푝 = (11) ( ) ( ) ( ) 1 = + (17) In which the푡푝푙 durations푛퐵퐶+ 퐷are∙ 푡 퐵퐶obtained+퐷 from statistical 1 1 1 푦푒푎푟 푦푒푎푟−푢푛푝푙 푦푒푎푟−푝푙 information, and at the planned disconnections it is 푃 푃 푃 considered that the revision of the disconectors from 4.4.2. Annual Penalties for Non-Delivery of Power the busbar collector and the step busbar is made Energy in case of inavailability in the cells, simultaneously. [€/year]

4.2.2. The Non-Delivery Time in case of ( ) ( ) inavailability in the cells zone, = [hour/year&cell] 2 2 푃푦푒푎푟−푝푙 ∑ 푆푚푒푑 푛표푛−푑푒푙푖푣푒푟푦 푝푙 ∙ 푡푝푙 ∙ 푑푠푝 (18) For Un ≥ 110 kV (figure 5), the usual elements for ( ) a cell are the circuit breakers, switch mechanism of = the circuit breakers, three current transformers, three 2 ( ) (19) single-phase separators, three monophase voltage 푃푦푒푎푟−푢푛푝푙 ∑ 푆푚푒푑 푛표푛−푑푒푙푖푣푒푟푦 푢푛푝푙 ∙ 2 transformers, surge arrestors, earthing switch. We ( ) ( ) ∙ 푡푢푛푝푙 ∙ 푑푠푝( ) determine the disconnection duration for every cell, = + (20) 2 2 2 taking into account the elements that a cell is 푦푒푎푟 푦푒푎푟−푢푛푝푙 푦푒푎푟−푝푙 composed of: 푃 푃 푃

80 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

4.4.3. Total Annual Penalties for Non-Delivery of to the imposed restrictions, for a = 10%, is Power Energy, [€/year] 1T x 320MVA.

This penalties are given by the sum of the damage Following the analysis of the data resulting from to the BC area and the damage to the cell area: the calculation of the short-circuit currents on the electric busbars collector [12], no limitation ( ) ( ) = + (21) measures for Issc are required because at any other 1 2 point (on the electric lines, etc.), the short-circuit 푃Observation.푦푒푎푟 푃푦푒푎푟 The푃푦푒푎푟 damage calculation can be currents are lower than those calculated on the systematized in the form of Table 3. Increasing costs busbars substations. at electric power suppliers, due to adoption of some The results of calculation are also measure of improvement the electric power supply used to select switching devices, adjust protection, quality can be balanced by increase of the turnover, and ensure electromagnetic compatibility. by increase of the sale of electric power or by increase of the selling price optim. We proposed and analyzed:

Table 3. The Cost of Penalties for Non-Delivery of Power • 5 variants of connection schemes for the 400kV Energy decision rules substation:

1: busbar Zone 2: cells 5. Study case collector

Switching (1) (1) (2) (2) 5.1. Research question P − P − P − P − Scheme year pl year unpl year pl year unpl

The U1 voltage substation, with the voltage of Solutions 400kV, is interleaved into a loop in the transmission or distribution network of an energy system by 1BC m n means of two overhead electric lines LEA1 and 2 1 BCS m1 n1 p q LEA2 having each section s = 300mm and the lengths L1 = 180km and L2 = 220km. 2 BC 0 n2

The station with voltage U2 of 110kV is powered 1 BC + BT m2 n3 only by the U1. 0 q1 2 BC + BT 0 n4 The input of the power system in the case of three- phase short-circuits on the stations of 400kV is of the …….. order I = 29kA and I = 35kA. scc1 scc2 At the busbars collector of 110kV, an electric • Open-Terminal Air-Insulated - AIS: single demand is estimated, characterized by: busbar collector (1BC), one breaker – double • Duration of Maximum Load Ability: busbar collector (2BC), ring bus and 4 breakers for 3 circuits, shown in Figures 7-10. SM = 217MVA; • Metal-enclosed Gas Insulated - GIS: Single

• Annual Use Usage: TSM = 6000 hours/year. busbar collector (1BC), shown in Figure 11. • 3 variants of connection schemes for the 110kV 5.2. Objective substation: It is desirable to supply safe, quality and • Open-Terminal Air-Insulated - AIS: single economical efficiency, from the point of view of busbar collector (1BC), shown in figure 12 and socio-technical services, with the electric power (W, One breaker - double busbar collector (2BC), S ) of consumers connected to U . shown in Figure 14. M 2 • Metal-enclosed Gas Insulated - GIS: Single 5.3. Solutions busbar collector (1BC), shown in Figure 13. 3 Taking into account the SM, we identified three For all of these schemes, we applied the reasoning technically possible solutions for the 400/110kV outlined above. Calculations can be done with transformer. The most appropriate variant, according specialized programs.

TEM Journal – Volume 7 / Number 1 / 2018. 81 TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

Figure 7. A single bus configuration, AIS, 400kV. Figure 8. An breaker - double bus configuration, AIS, 400kV.

Figure 9. Ring Bus (polygon), AIS, 400kV Figure 10. Four breaker for three circuits (1.33breakers/circuit), AIS, 400kV

Figure 11. Ring bus (polygon), GIS, 400kV Figure 12. Single bus , AIS, 110 kV

82 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

Figure 13. Single bus , GIS, 110 kV Figure 14. Double bus, AIS, 110 kV

400kV 14000 12000 10000 8000

[10^3 Euro] [10^3 6000 4000 2000 0 Poligon Poligon 1.33Break 1BC 2BC (AIS) (GIS) er/Circuit CI 5067.84 6780.56 5854.64 7521.16 8726.4 COMMyear x Tst 567.09 758.75 644 841.62 976.48 Pyear x Tst 2510.25 2203.67 12.26 12.26 2307.91 PTDC 8145.18 9742.97 6510.9 8375.04 12010.8

Figure 15. The centralized results for PTDC in 400kV substation

110 kV

6000 5000 4000

[10^3Euro] 3000 2000 1000 0 1BC 1BC 2BC (AIS) (GIS) CI 2560.88 3365.84 3272.8 COMMyear x Tst 630.4374 828.602 805.6979 Pyear x Tst 1250.83 956.52 639.3952 PTDC 4442.15 5150.96 4717.89

Figure 16. The centralized results for PTDC in 110kV substation

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Section 4 is devoted to a calculation algorithm for 5.4. Results theoretical cost of penalties for non-delivery of According to the centralized results in Figure 15 power energy. In section 5, we applied the proposed and Figure 16, the optimum solution for the 400kV algorithm for a hypothetical but still semi-realistic substation is the one with the AIS ring bus, and the study case (400/110 kV substation). The results of optimal solution for the 110kV substation is the one the calculation were integrated into the economic with 1BC, AIS. criterion considered in section 3 for collaborative The selection of the optimal schemes for each decision making modeling. voltage level leads to the single-line diagram The method proposed is to be a key part of a larger illustrated in Figure 17. setup. Our immediate goal is to apply the methodology to a real modeling session for refurbishing substations.

References

[1]. Kezunovic, M., Guan, Y., Guo, C., & Ghavami, M. (2010, August). The 21st century substation design: Vision of the future. In Bulk Power System Dynamics and Control (iREP)-VIII (iREP), 2010 iREP Symposium (pp. 1-8). IEEE. [2]. Atanackovic, D., McGillis, D. T., & Galiana, F. D. (1998). The application of multi-criteria analysis to substation design. IEEE Transactions on Power systems, 13(3), 1172-1178. [3]. Cárdenas, J., De Viñaspre, A.L., Argandoña, R., De Arriba, C., Farooqui, H. (2012). The next generation of Smart Substations. Challenges and Possibilities, CIGRE. [4]. Sussman, J. (2007). Course materials for ESD.04J Frameworks and Models in Systems,

Spring 2007. MIT OpenCourseWare, Massachusetts Figure 17. Single-line diagram illustrates Institute of Technology. the optimal solution of the 400/110kV station, designed Available: http://ocw.mit.edu from the point of view of the socio-technical systems [5]. Waterson P.E., Older Gray M.T., Clegg C.W. (2002). A sociotechnical method for designing work 6. Conclusion and Future Directions systems, Human Factors, 44(3), 376-391. The power stations in the power plants are socio [6]. Mumford, E. (2006). The Story of Socio-Technical technical systems of high operational responsibility, Design: Reflections on its Successes, Failures and especially in the new deregulated and competitive Potential, Information Systems Journal, 16(4), 317- 342, DOI: 10.1111/j.1365-2575.2006.00221 environments. [7]. Meyer, E. T. (2006, September). Socio-technical The cost savings and environmental pressures on interaction networks: A discussion of the strengths, utilities will cause utilities to run their networks and weaknesses and future of Kling’s STIN model. substations closer to the design limits of the In IFIP International Conference on Human Choice equipment. and Computers (pp. 37-48). Springer, Boston, MA. A key problem in many organisations that we [8]. Costinas, S., Tristiu, I., Sava, G. N., Opris, I., & believe that represents a significant contributor to Tanasiev, V. (2015, June). A new mathematical system failures is the fact that there are often only model for assessing optimization decisions of the loading factor flowing through substation weak links between change processes and system transformers. In Environment and Electrical improvement processes. Engineering (EEEIC), 2015 IEEE 15th International In this paper, we have analyzed the decisions Conference on (pp. 2109-2114). IEEE. regarding the designing of the electrical substations [9]. Comanescu, Gh., Costinaş, S., Iordache, M. (2005). for the evacuation of the electrical energy produced Electrical Part of Power Plants and Substation (in in a power plant the quantification from the point of Romanian), Editura Electra ICPE Bucuresti. view of socio-technical services.

84 TEM Journal – Volume 7 / Number 1 / 2018. TEM Journal. Volume 7, Issue 1, Pages 74-85, ISSN 2217-8309, DOI: 10.18421/TEM71-09, February 2018.

[10]. Costinaş, S., Ionescu, C.S., Opriș, I., Nistoran, D., [20]. Amin, S. M. (2016). The Grid Under Sava, N.G. (2015). Multi-criteria aproach, key to Fire. Mechanical Engineering, 138(12), 34-38. development substations maintenance management [21]. Baracu, T., Costinas, S., Ghiaus, C., Badea, A., solutions, ACEMP-OPTIM-Electromotion, Side, Avram, R., Vladulescu, F., & Jugravescu, D. (2016). Turkye, pp. 198-205, DOI: 10.1109/OPTIM.2015. New analytical methodologies for radiative heat 7426956. transfer in enclosures based on matrix formalism and [11]. Allen, J., Wood, B., Wollenberg, F. (2012). Power network analogy. Applied Thermal Engineering, 107, generation, operation, and control, John Wiley & 1269-1286. Sons. [22]. Zarakas, W., Pfeifenberger, J. (2013). Finding the [12]. Tristiu, I., Bulac, C., Costinas, S., Toma, L., Mandiş, Balance Between Reliability and Cost: How Much A., & Zăbavă, T. (2015, May). A new and efficient Risk Should Consumers Bear?, Western Conference algorithm for short-circuit calculation in distribution of Public Service Commissioners, Santa Fe, NM. networks with . In Advanced [23]. ACER (2014). Energy Regulation: A Bridge to 2025. Topics in Electrical Engineering (ATEE), 2015 9th Conclusions Paper. Ljubljana, Slovenia: Agency for International Symposium on (pp. 816-821). IEEE. the Cooperation of Energy Regulators. [13]. Opriş, I., Costinaş, S., Ionescu, C. S., & Nistoran, D. [24]. Pérez-Arriaga, I., Knittel, C. (2016). Utility of the E. G. (2017, March). Towards augmented reality in future, An MIT Energy Initiative response to an . In Advanced Topics in Electrical industry in transition, Engineering (ATEE), 2017 10th International Available: http://energy.mit.edu/uof Symposium on (pp. 39-44). IEEE. [25]. Gonzva, M., Barroca, B., Gautier, P. E., & Diab, Y. [14]. Leonardi, A., Mathioudakis, K., Wiesmaier, A., (2016, October). Analysis of disruptions cascade Zeiger, F. (2014). Towards the Smart Grid: effect within and between urban sociotechnical Substation Automation Architecture and systems in a context of risks. In 3rd European Technologies, Advances in Electrical Engineering, Conference on Flood Risk Management (FLOODrisk Article ID 896296, DOI: 10.1155/2014/896296. 2016) (Vol. 7, p. 07008). [15]. Costinas, S., Nemes, C., Tristiu, I., & Sava, G. N. [26]. US DHS. (2016). Critical Infrastructure Sectors: (2014, May). Quality cost of power supply and pay- Energy Sector, US Department of Homeland back capital of this. In Optimization of Electrical and Security. Available: www.dhs.gov/critical- Electronic Equipment (OPTIM), 2014 International infrastructure-sectors. Conference on (pp. 124-129). IEEE. [27]. Zinaman, O., Miller, M., Adil, A., Arent, D., [16]. Opriş, I., Costinaş, S., Ionescu, C., & Nistoran, D. Cochran, J., Vora, R., ... & Kauffman, R. (2015, May). The household energy consumer in a (2015). Power systems of the future: a 21st century smart metering environment. In Advanced Topics in power partnership thought leadership report (No. Electrical Engineering (ATEE), 2015 9th NREL/TP-6A20-62611). NREL (National International Symposium on (pp. 43-48). IEEE. Laboratory (NREL), Golden, CO [17]. United States Department of Agriculture, Design (United States)). Guide for Rural Substations, RUS Bulletin 1724E- [28]. Tollefson, G., Billinton, R., Wacker, G., Chan, E., & 300, 2001. Aweya, J. (1994). A Canadian customer survey to [18]. Amin, S. M. (2015). Power and Energy assess power system reliability worth. IEEE Infrastructure: Cyber Security, Defense, and Transactions on Power Systems, 9(1), 443-450. Resilience. Geo. J. Int'l Aff., 16, 70. [19]. Costinaş, S., Otomega, B., Cherecheş, T., Sava, C.A., Ioniţă, E. (2009). Management of Emergency Situations Resulting from Technological Hazard, Natural Catastrophes and Terrorist Attacks, 11th WSEAS International Conference On Sustainability In Science Engineering, Timisoara, Romania, pp. 320-324.

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