fault level at 11kv system

Your IP: Electric power is an essential facilitator for sustainable development of the modern SelCompTitle. SNTL Prague, Czech Republic, 1970. Posted By : / actual instructions in flowcharting are represented in /; Under :nose exercise before and afternose exercise before and after h. Maximum system fault level at 33 kV & 11kV bus es shall be 26.2kA for 1 sec & 18.3kA for 1 sec respectively. If you are using our Services via a browser you can restrict, block or remove cookies through your web browser settings. Normally short circuit fault is not a hardship to detect and solve since the fault current is big enough to see by the over-current relay; but earth fault is different, with small fault current that possibly down to 1A during high impedance earth fault, the over-current relay will fail to detect earth faults. can be used for calculation of symmetrical and unsymmetrical faults, voltage drop during motor start-up, or steady-state. Single Phase with Cable Run. Joined: 12 January 2012. Copyright 1998-2023 engineering.com, Inc. All rights reserved.Unauthorized reproduction or linking forbidden without expressed written permission. As mentioned earlier, the first step is the calculation of the MVA level of each component and converting the single line diagram to its equivalent MVA diagram. 192.1: Source Impedance = MV System fault MVA / Base MVA = 0.0008: LT Transformer impedance at 0.63MVA & 11kV Base = 0.05: Total MV system impedance (MV System + LT Transformer) = 0 . In static and balanced power system components like transformer and lines, the . There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. Fault Level Calculation For Generator . Click Here to join Eng-Tips and talk with other members! The fault currents correspond to a worst-case transformer impedance of 90% of nominal impedance, as transformer standards allow for a 10% tolerance on nominal impedance. The maximum three-phase fault currents that can be expected on the Low Voltage (LV) terminals of a distribution transformer are set out in the table below. (kV) Break Time (mS) 11kV (incl 6.6kV etc) 90 33kV 90 132kV 70 275kV and 400kV 50 Table 1 - typical break times by system voltage Some of them are listed below: This method can be used when the task is limited only to finding the short-circuit current at the short-circuit location. The following concepts are used while planning BigchainDBs safety efforts: , (Blockchain, Big Data and Machine Learning: Trends and Applications). This is due to the impedance earthing used at these levels. Same fault level on 11X2. Hello! Nos. . Basic Baking Ingredients and Their Functions, HVDC and FACTS for Improved Power Delivery Through Long Transmission Lines. voltage. Next, for the 69/12kV X=0.076 p.u. The transformers are delta-star connected with the star point of each 11 kV winding, solidly earthed. This data can be used in substation earthing system design and assessment. The padmount transformer size is also written on the tank (for newer transformers). A consumer is supplied at 380V 3 phase from a 11 kV substation through a 1500 kVA 11kV/380V transformer and a 380V cable as shown in Fig. Fault Level Calculations - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. Tap here to review the details. Valid from 1.10.2016. The percentage impedance of a transformer has a major effect on system fault levels. We pay respect to Elders past and present. Our short term solution involved two tapped reactors (operating in parallel) to segregate the older 250MVA network from the new 350MVA rated equipment. [3] Kakilli, A.: System Analysis with the MVA Method for Symmetrical Three-Phase Faults. Based on the available statistical data, Ekiti State is reported to ThinkScan SR2 car code scanner supports 4 in 1 data display, saves, reads and prints health reports. Solution: Alternator percentage reactance is based on its own voltage and kVA ratings. I have discussed it in other parts of this book, but you must always communicate a high energy level. Note that some older transformers may have different LV fuse sizes installed as compared to the current standard fuse size, and some padmount transformers may have an LV circuit breaker installed. The sequence impedance varies with the type of power system components under consideration:-. Free access to premium services like Tuneln, Mubi and more. /Filter /FlateDecode What is the fault level in 11kV? The analysis is done by using In order to validate the accuracy of the MVA Method, we will calculate the initial symmetrical short-circuit current at the fault point using the calculation method based on IEC 60909. Site growth took our fault level beyond the existing equipment's 250MVA rating with a predicted level of 350MVA. /F1 6 0 R Please note that there may be a fee for this service. The fault level at the bus is. It's recommended this table is used when designing your network. New connections of distributed generation and embedded generations which increases fault levels are individually assessed to ensure limits are not infringed. In conventional power systems, the system . of customer 11-kV main switch shall have an operating time not exceeding the maximum allowable time-current curves for phase fault and earth fault as shown in Drg. At each voltage level the fault level can be ascertained from the reactances given. We distinguish between these various portions of the power system by voltage levels as follows: Generation: 1kV-30 kV. Star Lesn, Slovakia, 2001. C : 500 MVA. series/parallel combination of the impedances upstream. Many thanks. A : 1000 MVA. b. The equivalent MVA diagram is shown in figure 2. Two parallel alternators each rated 11 kV 50 MVA and each having sub transient reactance of 15% are connected to a bus bar. The maximum rating of 11 kV SF6 or vaccum circuit breaker is assumed to be 4000 amps as allowable rated continuous current. Dynamic Performance of Distance Relayson Series Compensated Transmission Line 60232804 ppt-compensation-techniques-in-ac-transmission-system-using-c, fault location estimator in series compensator. We use cookies to enhance your experience while using our website. This may not be the case for old power station sites where non-standard arrangements are used or where impedance earthing is not used (5 MVA transformers). Primary Functions of Current Limiting Reactor. Already a Member? Voltage level (kV) Short circuit level (MVA) Short circuit level (kA) 132kV: 25/31.5 kA: 110kV: 25/31.5 kA: 33kV: 13.1/25 kA: 11kV . security level of the 11kV distribution system. Based on the available statistical data, Ekiti State is reported. transmission network 4 Fault Level Calculations Typical State Level Power System & our area of interest . I'm sure our frineds in the petro-chem and other heavy industries would know all about this problem! . Enjoy access to millions of ebooks, audiobooks, magazines, and more from Scribd. Demonstrate the solution at an 11kV substation. The next steps are based on the simplification of an equivalent MVA diagram to one final value of MVA at the fault point (this represents short-circuit MVA at the fault point). /F2 9 0 R Instant access to millions of ebooks, audiobooks, magazines, podcasts and more. As you know, interviewing is a staged, contrived event. A Fault Analysis of 11kv Distribution System (A Case Study of Ado Ekiti Electrical Power Distribution District) American Journal of Electrical Power and Energy Systems. within the project area were added to the existing 11kV network models currently used by system planners when assessing generation connections. I need to know the fault current at one of the sites to enable a design of the earthing grid to proceed. Jun 2007 - Nov 20114 years 6 months. >> MV System fault level (Maximum) = 40 kA: 6. I think in Aus, sparks get to do more HV work. Corresponding to 1.94kA. For above or equal 400 KV system the insulation of circuit breaker should be capable of withstanding 5% above the normal system voltage. Fault Level Calculations 8 What is fault level ABC Transmission Co. Ltd. 3 Ph Fault Levels For 2010- 2011 14530 MVA 18290 MVA 9700 MVA 8400 MVA 11300 MVA 4630 MVA 5800 MVA 6400 MVA 7200 MVA 2700 MVA 1185 MVA 3670 MVA 9730 MVA S/S - B S/S - A S/S - C 14530 MVA 8400 MVA 9730 MVA S/S - B. This is usually achieved by opening the circuit breaker connecting two sections of a substation or generating station busbar. . By joining you are opting in to receive e-mail. A simplified calculation is often sufficient. Maximum short-circuit (three-phase) levels normally experienced in the British system are as follows: 275 kV, 15000 MVA; 132kV, 3500MVA . Click to reveal f you are working on an 11KV distribution network, then your employer should have trained you, or ensured you were adequately trained before they employed you. << I am result oriented Engineer with long practical experience in field engineering, construction supervision of projects, engineering services, Plants operation, reliability & maintenance, and engineering consultancy. Diversified in setting up, and development of Feed and detailed design for electrical & Instrument installations for building services, Infrastructure, power house, gas . Design of LV Electrical and DCS, PLC and Controls schemes design system for Submarine (New Generation type Scorpene) Understanding the technical & contract documents from . Is changing out switchgear an option for you? Therefore in order to compensate for this, the primary generation voltage would be; the required nominal voltage + transmission losses. That means, rated voltage of circuit breaker corresponds to the highest system voltage. The short-circuit MVA at 275 kV busbars in Britain is normally, Figure 7.19 Typical transmission system. For general enquiries, call from 7:00am to 5.00pm Monday - Friday, or call after hours for planned interruption enquiries. A Fault Analysis of 11kv Distribution System (A Case Study of Ado Ekiti Electrical Power Distribution District) American Journal of Electrical Power and Energy Systems. 11KV : Amp Rating : 1250 A : Fault Level : 25 KA : Minimum Order Quantity : 1 Set : View Complete Details. Network modelling indicates that site fault levels will drop by 40-45% with this connection mode. You are using an out of date browser. The table below lists design fault level limits that apply at our installations. A High Integrity Isolation System was developed to provide a single isolation point for the safe and effective isolation of the complete longwall face 11kV and 3.3kV drive systems for non electrical works. Having experienced in fault analysis, trouble shooting and rectification of electrical system. This method is popular because of its simplicity and relative accuracy. It is easy to calculate the maximum current that a transformer can deliver under symmetrical fault conditions. Register to receive SMS notifications for power outages in your area. Abstract: - The aim of this research work is to carry out a fault analysis of 33KV distribution system using Ekiti state as a case study. The transformer fault level calculator assumes that the transformer is supplied from an infinite bus. We've encountered a problem, please try again. << 109.175.24.5 [6] Mslo, K. et al. Earthed system refers to a three phase system whose star point is grounded directly and the voltage between the healthy phases and the ground will be - 11kV/1.732 or 6.6/1.732. 50 MVA MVA 10.21% 132/33-11 kV Harsool 50 MVA 132/33-11 kV 10.88 % . A microprocessor is the center of the system, with storage devices, input and output peripherals, a power supply, human-computer interaction devices, and other necessary supporting facilities. A 3-phase, 10,000 kVA, 11 kV alternator has a sub-transient reactance of 8%. New consumer unit required - does it mean none fire rated down lighters need replacing? Submit your self-meter reading, connection application or make a claim, Submit a Electrical Work Request (EWR) or Connect application, Past Distribution Annual Planning Reports, Price List for Alternative Control Services, Distribution loss factor calculation methodology. I (fault) = 25 x 100 / (1.732 x 440 x 5) I (fault) = 0.66 kA. Prague, Czech Republic, 2013. Academic library - free online college e textbooks - info{at}ebrary.net - 2014 - 2023. For above or equal 400 KV system the insulation of circuit breaker should be capable of withstanding 5% above the normal system voltage. Normally fault level depens on the client requirment. The fault level of the 11kV substation is 250 MVA. Since the system operates normally before the fault, there will be no current I f through that source. SYSTEM STUDY IN 11 KV HT SYSTEMS . The earthing fault level dataset includes the three-phase and single-phase to earth fault levels for all Grid (132kV, 66kV, 33kV) and Primary (33kV, 20kV, 11kV, 6.6kV) substations based on the UK Power Networks Long Term Development Statement (LTDS). Maximum allowable fault levels set out by OEB Nominal Voltage (kV) Maximum 3-Phase Fault (kA) Maximum SLG fault (kA) 500 80 (usually limited to 63 kA) 80 (usually limited to 63 kA) 230 63 80 (usually limited to 63 kA) 115 50 50 44 20 19 (usually limited to 8 kA) 27.6 (4-wire) 17 12 27.6 (3-wire) 17 0.45 13.8 21 10 Table 2. stream Maximum short-circuit (three-phase) levels normally experienced in the British system are as follows: 275 kV, 15000 MVA; 132kV, 3500MVA; 33kV, 750/1000MVA; 11 kV, 150/ 250 MVA; 415 V, 30 MVA. Voltage level (kV) Short circuit level (MVA) Short circuit level (kA) 132kV . Login. For overhead power lines, the short-circuit MVA can be calculated directly from the impedance in form Zv=R+jX, therefore we can write. 27-36. doi: 10.11648/j.epes.20140302.13 Abstract: The aim of this research work is to carry out fault analysis of 11KV distribution power system . control of voltage ratios during short-circuit and during the start-up of large asynchronous motors. Three 15MVA transformers, connected in parallel, are used to step down to an 11 kV busbar from which six 5 MVA, 11 kV motors are supplied. wn|3h;rmoxw.0~58BB&_*Hx/d~n-*~YP!6V63W_QbPBsUQ;O62G _`c CO,'0Aa Accordingly, a primary-to-secondary distribution system, consisting of both medium voltage (MV) and low voltage (LV) The invention of a Switchgear should be rated So, continuous power supply to the consumer is necessary without any interruption. Looks like youve clipped this slide to already. Keywords: short-circuit current, the MVA method, calculation methods. Dear Sir, We want to find the fault level at the transformer secondary. For 66/11 kV substation, following minimum electrical & safety clearances are required. Welcome to the forum, we are UK based as stated above, however calculating the fault levels are the same. The actual maximum fault currents will change over time, including as a result of any reconfigurations of the electricity distribution system or transmission system, penetration levels of embedded generators (eg solar PV) and demand conditions at the time. As the transmission voltages increase, the short-circuit currents also increase, and for the 400 kV system, circuit breakers of 35 000 MVA breaking capacity are required. He suggested. Power System Review: Module 6. The embedded hardware primarily includes the processor, memory, bus, peripheral devices, I/O ports, and various controllers. Selecting P base as 20 MVA and V base as 11 kV and using the above equations: and the Line-Neutral voltage on the secondary of the transformer is 0.4/3 = 0.230 kV, giving: Three At a sub station, the level of secondary transmission voltage (132kV, 66 or 33 kV) reduced to 11kV by step down transforms. Figure 1-2 shows a configuration diagram of a typical embedded system consisting of two main parts: embedded hardware and embedded software. contains simple formulas for calculation (in comparison with other methods). The results are then compared to the maximum allowable short circuit fault level rating of the switchgear, plant and lines to identify if plant is operated within fault level ratings. the lower impedance, implies that the power system is stronger at that point and vice versa [1, 2]. }i%G9"Ucj8/RrdssK~J=Y]4$\2.I$7s7 7`w~cIy@= :R.Wjo.uVnPYhF.R,.R` . Lets see the calculation Learn More: What is Step potential and Touch Potential and Calculation 10 KV X 110% = 11 KV 20KV X 110% = 22 KV 30 KV X 110% = 33 KV 60 KV X 110% = 66 KV 100KV X 110% = 110KV 120 KV X 110% = 132KV In this paper, a new approach related to the noncontact magnetic field (MF)-based measurement system to localize SC faults on 11-kV overhead distribution lines is presented. fault level at the start of the feeder, Approximately 3-5kA 3 ph. Fault Level Calculation 1. The MVA method is known to be simple, quick, and easy, and is sufficiently accurate for engineers in practice for basic estimation of fault levels at any point in an electrical network. Worked on oil and gas industrial projects performed power system studies, to select major electrical equipment . [mcq] power system operation and control , power system operation and control mcq , power system operation and control mcq pdf . It determines the maximum value of current that will flow under fault conditions. Thank you very much for your reply % 132/33/11 kV substation system using ETAP software. Basic short circuit calculation procedure, Protective devices and their coordination in power systems, Electrical substation (one and half breaker scheme), Measurement of hvac (High Voltage Engineering ), 220 KV Substation Operation & Maintenance, 3. The single line diagram makes the system easy and it provides the facilitates reading of the electrical supply and connection. control of circuit breakers switching capability. The aim of this research work is to carry out a fault analys is of 33KV distribution system using Ekiti state as a case study. Figure 7.4 shows two 11 kV generators feeding a 132 kV double circuit line through generator transformers. Ltd. Meerut, Installation, Testing and Troubleshooting of Transformers, Generator protection calculations settings. It is evident that it follows the UTILITY capacity, since it's being lesser compared to. Your IP: presentation on substation layout and BUS bar arrangement. The equivalent short-circuit impedance at the fault point is calculated to be, If the value of initial symmetrical short-circuit current is known, the peak short-circuit current can be determined using. The fault currents correspond to a worst-case transformer impedance of 90% of nominal impedance, as transformer standards allow for a 10% tolerance on nominal impedance. It should be noted that the short- circuit level will change with network conditions, and there will normally be two extreme values: that with all plant connected and that with the minimum plant normally connected. For simplicity, resistance will be neglected. 7. Voltage (kV) Impulse Voltage (kV Peak) Power Frequency Voltage (kV) 1 0.433 - 3 2 11 75 28 3 33 170 70 11 LOSSES: 11.1 The transformer of HV voltage up to 11kV,the total losses(no-load + load losses at 75 0C) at 50% of rated load and total losses at 100% of rated load shall not exceed the maximum total loss and hence 2, 2014, pp. %PDF-1.5 Determination of Voltage Regulation and Power system losses, Determination of voltage regulation and power system losses, The important use of reactors in substations, Application of Capacitors to Distribution System and Voltage Regulation, Basic Fundamental Electronics by D-Sarda PART X, Basic Fundamental Electronics by D-Sarda PART IX, Basic Fundamental Electronics by D-Sarda PART VIII, Basic Fundamental Electronics by D-Sarda PART VII, Basic Fundamental Electronics by D-Sarda PART VI, Basic Fundamental Electronics by D-Sarda PART V, Basic Fundamental Electronics by D-Sarda PART IV, Basic Fundamental Of Transistors by D-Sarda, Basic Fundamental Electronics by D-Sarda PART III, Basic Fundamental Electronics by D-Sarda PART II, No public clipboards found for this slide, Enjoy access to millions of presentations, documents, ebooks, audiobooks, magazines, and more. Single Phase with Cable Run. voltage. What is the fault level for a fault on one of the feeders near the bus bar? Our nominal maximum (design) fault level is 13kA (250MVA). Summer Training presentation on 132/33 KV sub-station Minto park, Allahabad, Sudhir Cement Industries Pvt. The kit shall be used for cable types namely XLPE, PVC, PILC with Al / Cu conductor. For an underground area, engage an Exclusion Zone Officer who can assess conductor sizes, for example lift pillar lids, open pad mounts and ground substations. Let's now describe the network components for which we will calculate the fault levels: The 11kV incoming terminals (source fault current) The auxiliary transformer's 11kV terminals The 6.6kV switchgear bus The service transformer's 6.6kV terminals The 415V PCC panel bus The 415V MCC panel bus If your fault levels are below 10kA, of course, 20kA is better than 12.5kA as it is more capable breaker and can be used even after your fault levels go up in future. High voltage fault level limits. Infintite bus assumption. Ergon Network acknowledges the Traditional Custodians of the land on which we live and work, and recognise their continuing connection to land, waters and community. It is based on a mathematical modification of the ohmic method. Now we can reduce the equivalent MVA diagram. design of electrical equipment (from the point of view of thermal and dynamic effects of short-circuit currents). fault level at 11kv systemplymouth township mi police scanner. Weve updated our privacy policy so that we are compliant with changing global privacy regulations and to provide you with insight into the limited ways in which we use your data. Indoor and Outdoor Termination for 11 kV, 22 kV and 33kV Cables Used in MSEDCL 2.1 Nominal System Voltage : 11kV, 22kV, 33kV 2.2 Voltage variation on supply side : 10 % 2.8 Fault level As a (kV) Break Time (mS) 11kV (incl 6.6kV etc) Demand of power increases day to day. $OmR7@(5! and is generating 1.15 pu voltage. (Triple Zero) To report life threatening emergencies like fallen powerlines or shocks & tingles. 15 MVA transformer use MVASC = MVA / Zp.u. Hand written calculations are hard and laborious often flawed because of all the conversions required. Actual Fault Current available at AC distribution board . The following tables provide quick order of magnitude fault levels for a a range of typical low voltage Assume system fault at the point of supply to be 250MVA @ 11KV and no load Point of Supply : 11KV, 250MVA Fault Level Transformer : 315KVA, 11KV/400V, 4% Z Supply Cable : 50 m - 240 mm. Energex acknowledges the Traditional Custodians of the land on which we live and work, and recognise their continuing connection to land, waters and community. calculation of induced voltage in telecommunication lines caused by high-voltage or extra-high-voltage networks. So they had planned to deliver the desired voltage with 10 % as extra (110%) to match the transmission loss and line drop. By whitelisting SlideShare on your ad-blocker, you are supporting our community of content creators. Regards, Informative article re calculating fault currents using MVA method. Dostupn na internete: < http://www.jmpangseah.com>. . Here in the following case, we will calculate the fault current and fault level of the three-phase symmetrical short circuit fault occurring at 22 kV bus bar indicated by F. 15 MVA transformer use MVASC = MVA / Zp.u. The 3-phase short-circuit fault level P SC, in kA or in MVA [1] is given by the power supply authority concerned, from which an equivalent impedance can be deduced. Please download the latest version for the best user experience: Internet Explorer (version 10 or higher), Chrome, Firefox, Safari or Opera. [1] Jaffari, H.: Fault Current Calculation. Work Record : Feb - 2016 to Feb-2018 Position : Electrical Technician (Operation & Maintenance) Company : Federal Electricity and water authority Working in Centralized Operation & Maintenance Department, Maintenance of Substation & Condition monitoring (Transmission line like power transformer, OHL feeders 220kv/132/33 KV, cable feeder, towers, PMTs, OPGW, tower earth resistance . The typical hardware structure of an embedded system is shown in Figure 1-7. /MediaBox [0 0 595 842] endobj Add Transformer to System. The results based on IEC 60909 calculation method will be used as a reference. The fault level of the 11kV substation is 250 MVA. These can be divided into numerical and numeric-graphical methods. MV System fault MVA = 3 x 40 x 11 = 762 MVA: Calculation. Its a two step process as follows: Rule of thumb for Brisbane Urban substations at 11kv include: Have a question? SelSystemTypeTitle. Industrial Electrical System Design complying to IEC, NATO, NEC, NAVY & IS standards. FAULT LEVEL CALCULATION Dinesh Kumar Sarda 2. 2, A possible guide to maximum 11kV Fault level is that if the 2.5MVA transformer is assumed to be on infinite 66kV bus bars, then the maximum fault level at the substation 11kV bus The aim of this research work is to carry out fault analysis of 11KV distribution power system. Sometimes, if the system MVA is not available, but its voltage and impedance are given, the short circuit MVA can be calculated by MVASC = KV2 * Y formula. Copyright Energex 2023. The substation is equipped with three 10-MVA 33/11-kV transformers, one of which runs on hot standby to avoid exceeding the fault-level rating of the existing 11-kV switchgear. Enter your email address to subscribe and receive notifications of new posts by email. A transformers nameplate details are 25 kVA, 440V secondary voltage, 5% of percentage impedance, calculate the short circuit fault current. The soil conditions considered are desert conditions and hence with poor resistivity. It can be seen that the MVA method gives results with sufficient accuracy. The next steps are based on the simplification of an equivalent MVA diagram to one final value of MVA at the fault point (this represents short-circuit MVA at the fault point). Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. By accepting, you agree to the updated privacy policy. All rights reserved. System strength is referred to the system impedance seen at that point. The group currently is currently S.Mathankumar 1, V.Agalya ,Member IEEE . Hi. During the study, the condition of all relevant equipment for power distribution at the 11 kV level was assessed. When the insulation of the system fails at one or more points or a conducting object comes Philosophy change to primarily operate the 11 kV system as a single power system island. Fault Level means the current expected to flow into a short circuit at a stated point on the System, and which may be expressed in kA or in MVA. *Eng-Tips's functionality depends on members receiving e-mail. Table 1. 2, 2014, pp. /F3 12 0 R Regards, Shaheed P PhilCorso Objective : To be a part of an Organisation where, my knowledge and capabilities can be utilised in a creative way & challenging environment for achieving goals and to upgrade my abilities and skills to grow up in the corporate ladder. worked with Siemens PLC S7-400 and also on the WINCC redundancy worked on Constant Current Regulator (CCR) of high voltage of 30 kv, 25 kv, 20 kv, 15 . If in the same plant, these generators are being replaced by . SUMMARY More than 18years' experience in engineering & design of large industrial, electrical generation power plant and petrochemical plants. In this paper, the last factor, i.e. The embedded software usually contains (Android Application Development for the Intel Platform). For a better experience, please enable JavaScript in your browser before proceeding. SAP Training ( PS , Material PR , Service PR ,Cost Planning , Budgeting , PO M. Arkam C. Munaaim Adj. Activate your 30 day free trialto unlock unlimited reading. clear and easy to follow. Join your peers on the Internet's largest technical engineering professional community.It's easy to join and it's free. Street lighting, as well as the switching control for street lighting, can be installed in a substation. Calculate the fault level for a three-phase fault at: Figure 7.4 Line diagram and equivalent circuits for Example 7.2. a. For sake of simplicity, we consider only one synchronous generator, TG, and one synchronous motor, SM1 in the industrial power network.