max power flow from grid in p.u. (rating of line 1)
", "templateType": "anything", "can_override": false}, "S2": {"name": "S2", "group": "Ungrouped variables", "definition": "precround(PL2+PL3,2)", "description": "", "templateType": "anything", "can_override": false}, "S3": {"name": "S3", "group": "Ungrouped variables", "definition": "precround(1.2*PL3,2)", "description": "", "templateType": "anything", "can_override": false}, "SCDFstep1": {"name": "SCDFstep1", "group": "Ungrouped variables", "definition": "random(50 .. 300#10)", "description": "", "templateType": "randrange", "can_override": false}, "SCDFstep2": {"name": "SCDFstep2", "group": "Ungrouped variables", "definition": "random(50 .. 300#10)", "description": "", "templateType": "randrange", "can_override": false}, "SCDFstep3": {"name": "SCDFstep3", "group": "Ungrouped variables", "definition": "random(50 .. 300#10)", "description": "", "templateType": "randrange", "can_override": false}, "SCDF1": {"name": "SCDF1", "group": "Ungrouped variables", "definition": "[0,SCDFstep1,2*SCDFstep1,4*SCDFstep1,8*SCDFstep1,16*SCDFstep1]", "description": "", "templateType": "anything", "can_override": false}, "SCDF2": {"name": "SCDF2", "group": "Ungrouped variables", "definition": "[0,SCDFstep2,2*SCDFstep2,4*SCDFstep2,8*SCDFstep2,16*SCDFstep2]", "description": "", "templateType": "anything", "can_override": false}, "SCDF3": {"name": "SCDF3", "group": "Ungrouped variables", "definition": "[0,SCDFstep3,2*SCDFstep3,4*SCDFstep3,8*SCDFstep3,16*SCDFstep3]", "description": "", "templateType": "anything", "can_override": false}, "Life": {"name": "Life", "group": "Ungrouped variables", "definition": "random(10 .. 40#5)", "description": "", "templateType": "randrange", "can_override": false}, "Capital": {"name": "Capital", "group": "Ungrouped variables", "definition": "random(500 .. 3000#100)", "description": "", "templateType": "randrange", "can_override": false}, "OnM": {"name": "OnM", "group": "Ungrouped variables", "definition": "random(0.05 .. 2#0.05)", "description": "", "templateType": "randrange", "can_override": false}, "circuits": {"name": "circuits", "group": "Ungrouped variables", "definition": "['EG1Circuit.png','EG2Circuit.png','EG3Circuit.png']", "description": "", "templateType": "anything", "can_override": false}, "which": {"name": "which", "group": "Ungrouped variables", "definition": "random(0 .. 2#1)", "description": "", "templateType": "randrange", "can_override": false}, "Pmax": {"name": "Pmax", "group": "Ungrouped variables", "definition": "precround(10*S1,0)", "description": "max power flow from grid (80% of load)
", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["N1", "N2", "N3", "PL1", "PL2", "PL3", "QL1", "QL2", "QL3", "Lambda1", "Lambda2", "Lambda3", "r1", "r2", "r3", "R1pu", "R2pu", "R3pu", "X1pu", "X2pu", "X3pu", "B1pu", "B2pu", "B3pu", "S1", "S2", "S3", "SCDFstep1", "SCDFstep2", "SCDFstep3", "SCDF1", "SCDF2", "SCDF3", "Life", "Capital", "OnM", "circuits", "which", "Pmax"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Figure 1 shows a section of the 10 kV distribution system with three loads. The generator shown represents the bulk supply point (BSP) where the section connects to the main grid supply. All sections in the system are fully protected.
\n{image('resources/question-resources/'+circuits[which])}
\nFigure 1: A section of the distribution system
"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "The load information is given in Table 1 and the line information in Table 2. All per-unit values are given on a 10 MVA base.
\n| \n Load \n | \n\n No. of Customers \n | \n\n Load Power [p.u.] \n | \n
| \n L1 \n | \n\n {N1} \n | \n\n {PL1} + j {QL1} \n | \n
| \n L2 \n | \n\n {N2} \n | \n\n {PL2} + j {QL2} \n | \n
| \n L3 \n | \n\n {N3} \n | \n\n {PL3} + j {QL3} \n | \n
Table 1: Load information
\n| \n Section \n | \n\n $\\lambda$ \n[fails/year] \n | \n\n r \n[hours] \n | \n\n Impedance \n[p.u.] \n | \n\n Susceptance \n[p.u.] \n | \n\n MVA Limit \n[p.u.] \n | \n
| \n 1 \n | \n\n {Lambda1} \n | \n\n {r1} \n | \n\n {R1pu} + j {X1pu} \n | \n\n {B1pu} \n | \n\n {S1} \n | \n
| \n 2 \n | \n\n {Lambda2} \n | \n\n {r2} \n | \n\n {R2pu} + j {X2pu} \n | \n\n {B2pu} \n | \n\n {S2} \n | \n
| \n 3 \n | \n\n {Lambda3} \n | \n\n {r3} \n | \n\n {R3pu} + j {X3pu} \n | \n\n {B3pu} \n | \n\n {S3} \n | \n
Table 2: Line information
"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "The sector customer damage functions are given in Table 3 for the three loads in €/MW.
\n| \n \n | \n\n Time [hours] \n | \n|||||
| \n Load \n | \n\n 0 \n | \n\n 1 \n | \n\n 2 \n | \n\n 3 \n | \n\n 4 \n | \n\n 5 \n | \n
| \n L1 \n | \n\n 0 \n | \n\n € {SCDF1[1]} \n | \n\n € {SCDF1[2]} \n | \n\n € {SCDF1[3]} \n | \n\n € {SCDF1[4]} \n | \n\n € {SCDF1[5]} \n | \n
| \n L2 \n | \n\n 0 \n | \n\n € {SCDF2[1]} \n | \n\n € {SCDF2[2]} \n | \n\n € {SCDF2[3]} \n | \n\n € {SCDF2[4]} \n | \n\n € {SCDF2[5]} \n | \n
| \n L3 \n | \n\n 0 \n | \n\n € {SCDF3[1]} \n | \n\n € {SCDF3[2]} \n | \n\n € {SCDF3[3]} \n | \n\n € {SCDF3[4]} \n | \n\n € {SCDF3[5]} \n | \n
Table 3: Sector customer damage functions (SCDFs) for each load in €/MW
"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "A single generator (with cost data shown in Table 4) is to be added to this system to improve its performance and limit its power demand on the grid to a maximum of {Pmax} MW.
\n| \n Lifetime \n | \n\n {Life} years \n | \n
| \n Capital \n | \n\n € {Capital} per MW \n | \n
| \n O&M \n | \n\n {OnM} c per MWh \n | \n
Table 4: Generator cost data
"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Implement this system in power systems simulation software (PowerWorld, ETAP, MATLAB) and analyse its power flow (including voltage profile and power ratings). Comment on any issues identified.
\nThrough calculation and analysis of reliability indices and through cost evaluation, design an optimum solution for placement and sizing of the generator for this system. Show its effect on the system reliability and its economic viability. Implement your design in the simulator and use the software to demonstrate the improvements in performance.
\nDiscuss the types of generator that you might choose with respect to economic, technical and environmental considerations. Discuss, with demonstrations from your analysis, the technical, safety and economic benefits and drawbacks of embedded generation in this case.
"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question"}]}], "allowPrinting": true, "navigation": {"allowregen": false, "reverse": false, "browse": false, "allowsteps": false, "showfrontpage": false, "showresultspage": "never", "navigatemode": "sequence", "onleave": {"action": "none", "message": ""}, "preventleave": false, "typeendtoleave": false, "startpassword": "", "allowAttemptDownload": false, "downloadEncryptionKey": ""}, "timing": {"allowPause": false, "timeout": {"action": "none", "message": ""}, "timedwarning": {"action": "none", "message": ""}}, "feedback": {"showactualmark": false, "showtotalmark": false, "showanswerstate": false, "allowrevealanswer": false, "advicethreshold": 0, "intro": "", "end_message": "", "reviewshowscore": false, "reviewshowfeedback": false, "reviewshowexpectedanswer": false, "reviewshowadvice": false, "feedbackmessages": [], "enterreviewmodeimmediately": false, "showexpectedanswerswhen": "never", "showpartfeedbackmessageswhen": "never", "showactualmarkwhen": "never", "showtotalmarkwhen": "never", "showanswerstatewhen": "never", "showadvicewhen": "never"}, "diagnostic": {"knowledge_graph": {"topics": [], "learning_objectives": []}, "script": "diagnosys", "customScript": ""}, "type": "exam", "contributors": [{"name": "Jane Courtney", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2154/"}], "extensions": [], "custom_part_types": [], "resources": [["question-resources/EG1Circuit.png", "/srv/numbas/media/question-resources/EG1Circuit.png"], ["question-resources/EG2Circuit.png", "/srv/numbas/media/question-resources/EG2Circuit.png"], ["question-resources/EG3Circuit.png", "/srv/numbas/media/question-resources/EG3Circuit.png"]]}