EE 324 L SIMULATION LABORATORY

Transcription

1 Experiment No. 9 EE 324 L SIMULATION LABORATORY FAULT ANALYSIS OF A SIMPLE AC SYSTEM USING PSCAD Objective: Simulate the given power system network for L-L, L-L-G, L-L-L and L-L-L- G faults. Determine the voltage and current profiles under each fault. Software used :EMTDC/PSCAD (Ver ) Power System: given below A.0 B Va Ia Ea Ib C Vb Vc TL TL TL Eb Ec Ic 0.0 A B FAULTS C AB->G Timed Fault Logic Ia Va Ea Ib Vb Eb Ic PROCEDURE: Vc Ec To create a PSCAD project.. From the windows start menu choose PSCAD folder and then the PSCAD.EE shortcut to start PSCAD. 2. From the file menu, point to Create New Project and choose Case. 3. From the view menu select project. (Select Project Tree and clicking on message in view menu opens message tree where the error messages are displayed). 4. Open the new file (noname [psc]) by double clicks. 5. Save the project. ()

2 To place the parts (general). Open the project tree from view menu. 2. Open the master library. 3. Open the appropriate sub page. 4. Copy the required component. 5. Paste it in the project file. To place the source. From the master library, main page, choose the sub-page sources. 2. Select 3 phase grounded voltage source. 3. Copy the part from the master library and paste in design window 4. Right click on the part and rotate it appropriately. 5. Double click on the part to define its parameters as a) Configuration Source name : (optional) Source impedance: Resistive Phase shift: 0.0 Voltage input: Internal Frequency: Internal b) Resistance Resistance:.0 ohm c) Voltage Magnitude: 230 [kv] Ramp up time: 0.05 sec 6. Click OK To place the transmission lines. Select Tlines from the master library main page. 2. Place transmission line interfaces and transmission line as per the instructions given in the package. (2)

3 3. Double click on the transmission line (not interface) and edit the parameters as. Line Name: LT Frequency: 50 Hz Length of Line: 50km No. of conductors: 3 4. Choose the edit menu. 5. Right-click on the opened window Transmission Line TL and point to Tlines. 6. Select the third option, 3 Line constants 3 condutors delta tower. 7. Right click on the conductor arrangement and choose its physical parameters appropriately. 8. Close the window Transmission Line TL. 9. Double click on each transmission line interface and edit the parameters as Name: TL No. of equivalent conductors: 3 To place the wire/resistor/inductor/ground /connection node.. Right click and point to add. 2. Choose the part needed. 3. Double click the part to edit its parameters. To place the fault. From the fault page in master library choose the components in the diagram. 2. Copy and paste the part. 3. Double click Timed Fault Logic to set time to apply fault as 0.sec and 0.05sec. 4. Click OK. 5. Double click FAULTS to edit fault parameters as a) Configuration Fault Type Control: Internal Clear possible if current flowing: No b) Fault Resistance Fault On resistance: Fault OFF resistance: 0.0 ohm.0e6 ohm (3)

4 c) Fault type Is phase A in Fault: Is phase B in Fault: Is phase C in Fault: Is the fault to neutral: (Now the fault type is L-G) Yes No No Yes To place the meters. Right click and point to add, then to meters and select appropriate one, say voltmeter to ground. 2. Place the meter chosen, say in the A phase of the supply. 3. Double click on the meter and name the meter, say Va. 4. From add choose data label and channel. 5. Double click on the data label and edit signal name, as Va(should be same as that used for the corresponding meter). 6. Double click the channel and edit the title. ( this title is the one, which is displayed on the graph). 7. Connect the data label and channel using a wire. 8. Repeat the same for remaining two phases B & C. To plot Curve/Graph To create new plot.. Right click on the channel select Input/Output references and choose create new plot. 2. Double click on the graph to edit its parameters like Title, axes properties etc. To add a curve to existing plot (This can be used when it is need to plot more than one curve on a single graph like 3 phase voltages). Right click on the channel corresponding to the curve to be added. 2. Point to Input / Output references and choose add as curve. 3. Right click on the existing graph where the curve to be added and choose paste curve. (4)

5 To Execute. Open the project window. 2. Right click on the file name and Set as Active. 3. Click on the green play icon to start simulation. Questions: Part A What is a fault? Is it possible to protect the system from complete faults? 2 How reliability is related with protection? 3 What is grounding? 4 How the simulation time separated from fault clearing time? 5 Which type of fault is common to Indian Power System? 6 Which type of fault is severe w.r.to cascading? 7 Give your comments on the results. Questions: Part B Discuss the major features and capabilities of the software used for the simulation. 2 Can we use any other packages for the same experiment? 3 Explain briefly the solver options and time step for the simulation in the package. 4 Develop a programme (codes) by yourself for the problem with a suitable front end. (5)