Share Email. Top clipped slide. Download Now Download Download to read offline. Mathankumar S Follow. Matlab simpowersystem. Business environment scanning market survey tools and techniques by mathankumar. Related Books Free with a 30 day trial from Scribd. Related Audiobooks Free with a 30 day trial from Scribd. Elizabeth Howell. Heather Hove Dec. Spacing between the conductors in the bundle is 45 cm.
Find A, B, C, D constants, sending end voltage, current, power factor and power when the line is delivering full load of 50MW at kV, 0. AIM To determine the bus admittance and impedance matrices for the given power system network. In most of the power system studies it is required to form y- bus matrix of the system by considering certain power system parameters depending upon the type of analysis.
Y-bus may be formed by inspection method only if there is no mutual coupling between the lines. Shunt impedances are added to diagonal element corresponding to the buses at which these are connected.
The off diagonal elements are unaffected. The equivalent circuit of Tap changing transformers is included while forming Y-bus matrix. The bus impedance matrix is very useful in fault analysis. The bus impedance matrix can be determined by two methods. In one method we can form the bus admittance matrix and than taking its inverse to get the bus impedance matrix. In another method the bus impedance matrix can be directly formed from the reactance diagram and this method requires the knowledge of the modifications of existing bus impedance matrix due to addition of new bus or addition of a new line or impedance between existing buses.
The non-linear load flow equation is given by. Type and save the program in the editor Window. The magnitude at bus 1 is adjusted to 1. The scheduled loads at buses 2 and 3 are marked on the diagram.
Line impedances are marked in p. The base value is kVA. The line charging susceptances are neglected. Determine the phasor values of the voltage at the load bus 2 and 3. The load flow equations for Newton Raphson method are non-linear equations in terms of real and imaginary part of bus voltages. Consider the 3 bus system each of the 3 line bus a series impedance of 0.
The specified quantities at the bus are given below. Type and save the program. The one line diagram of a simple power system is shown in figure. The neutral of each generator is grounded through a current limiting reactor of 0. The system data expressed in per unit on a common MVA base is tabulated below.
Determine the fault current for the following faults. Fault level, post-fault voltages and currents for different types of faults, for the given network under symmetric and unsymmetrical conditions were computed and verified using MATLAB Software. Active power control is one of the important control actions to be perform to be normal operation of the system to match the system generation with the continuously changing system load in order to maintain the constancy of system frequency to a fine tolerance level.
This is one of the foremost requirements in proving quality power supply. A change in system load cases a change in the speed of all rotating masses Turbine — generator rotor systems of the system leading to change in system frequency. The speed change form synchronous speed initiates the governor control primary control action result in the entire participating generator — turbine units taking up the change in load, stabilizing system frequency.
Restoration of frequency to nominal value requires secondary control action which adjusts the load - reference set points of selected regulating generator — turbine units.
The primary objectives of automatic generation control AGC are to regulate system frequency to the set nominal value and also to regulate the net interchange of each area to the scheduled value by adjusting the outputs of the regulating units. This function is referred to as load — frequency control LFC. Create a new Model by selecting File - New — Model. Pick up the blocks from the simulink library browser and form a block diagram.
After forming the block diagram, save the block diagram. Evaluation Sheet: Gives your internal mark split —up. Index Sheet: Includes the name of all the experiments. Experiment documentation: It includes experiment name, date, objective, flowchart, algorithm, formulae used, Model calculation, problem solution, simulated output and print outs. Prelab and Postlab question should be written before and after completing the experiments.
Your work must be original and prepared independently. However, if you need any guidance or have any questions or problems, please do not hesitate to approach your staff in charge during office hours. The students should follow the dress code in the Lab session. Reports Due Dates: Reports should be submitted immediately after next week of the experiment. If a report is 3 days late, a grade of 0 will be assigned.
Prelab questions will be asked at the beginning of each cycle as a viva-voce and the post lab questions should be available in the observation and record after the completion of the experiment. Operation: The phase controlled rectifiers using SCRs are used to obtain controlled dc output voltages from the fixed ac mains input voltage. The circuit diagram of a half controlled converter is shown in Figure 1. The output voltage is varied by controlling the firing angle of SCRs. The single phase half controlled converter consists of two SCRs and two diodes.
During positive half cycle, SCR1 and Diode 2 are forward biased. Current flows through the load when SCR1 is triggered into conduction. During negative half cycle, SCR3 and D1 are forward biased. If the load is resistive, the load voltage and load current are similar. If the load is inductive, the current will continue to flow even when the supply voltage reverses polarity due to the stored energy in the inductor.
At the end of positive half cycle, D2 is reverse biased and D1 is forward biased. Load current now flows from supply via SCR3, load and D4. At the end of negative half cycle, the freewheeling current will flow through the diode D2 and SCR3. The circuit diagram of a fully controlled converter is shown in Figure 2. The single phase fully controlled converter consists of four SCRs. The nature of the load current depends on the values of R and L in the inductive load.
This is because the load inductance does not allow the current to go to zero instantly. Thus the energy stored in the inductance flows against the supply mains.
The numbering of SCRs 1, 3, 5 for the positive group and 2, 4, 6 for negative group. This numbering scheme is adopted here as it agrees with the sequence of gating of six thyristors in a 3-phase full converter. Here each SCR is conduct for At any time two SCRs, one from positive group and other from negative group must conduct together and this combination must conduct for Some of the important applications of AC regulators are: domestic and industrial heating, induction heating in metallurgical industries, induction motor speed control for fan and pump drives, transformer tap changers in utility systems, static reactive power compensators, lighting control etc.
Two thyristors in anti parallel are employed for full wave control. In this case, isolation between control and power circuit is most essential because of the fact that the cathodes of the two thyristors are connected to the common point. For low power applications, a triac may be used. In this case isolation between control and power circuitry is not necessary. Formulae Used: The triggering pulse is generated at the point at which the associated cosine wave becomes instantaneously equal to the control voltage.
A diac is a gateless triac designed to breakdown at a low voltage. During the positive half cycle, the triac requires a positive gate pulse for turning it on. This is provided by the capacitor C. When its voltage is above the breakdown voltage of the diac, the capacitor C discharges through the triac gate. When the triac turns on, the capacitor Voltage will be reset to zero. A similar operation takes place in the negative half cycles, and a negative gate pulse will be applied when the diac breaks down in the reverse direction.
Adjustment of series resistance, R determines the charging rate of capacitor C and hence the value of the phase angle delay. The output power and thus light intensity are varied by controlling the phase of conduction of the triac. Ybus matrix is often used in solving load flow problems. It has gained widespread applications owing to its simplicity of data preparation and the ease with which the bus admittance matrix can be formed and modified for network changes.
Of course, sparsity is one of its greatest advantages as it heavily reduces computer memory and time requirements. In short circuit analysis, the generator and transformer impedances must also be taken into account. In contingency analysis, the shunt elements are neglected, while forming the Z-bus matrix, which is used to compute the outage distribution factors.
This can be easily obtained by inverting the Y-bus matrix formed by inspection method or by analytical method. The impedance matrix is a full matrix and is most useful for short circuit studies. Initially, the Y-bus matrix is formed by inspection method by considering line data only. After forming the Y-bus matrix, the modified Y-bus matrix is formed by adding the generator and transformer admittances to the respective diagonal elements and is inverted to form the Z- bus matrix. V The admittances Y11, Y12,… Y1n are called the self-admittances at the nodes and all other admittances are called the mutual admittances of the nodes.
Yij is the series admittance in mho. Step 2: Read the self-admittance of each bus and the mutual admittance between the buses. Step 3: Calculate the diagonal element term called the bus driving point admittance, Yij which is the sum of the admittance connected to bus i.
Step 4: The off-diagonal term called the transfer admittance, Yij which is the negative of the admittance connected from bus i to bus j. Step 5: Check for the end of bus count and print the computed Y-bus matrix.
Step 6: Compute the Z-bus matrix by inverting the Y-bus matrix. Step 7: Stop the program and print the results. Sample Problem: The bus and branch datas for a 3 bus system is given in table below. Form Y bus matrix by inspection method. An algorithm for formulating [Zbus] is described in terms of modifying an existing bus impedance matrix designated as [Zbus]old. Trial software Contact sales. Assess performance and identify parameter settings using power system simulation and optimization Power system simulation involves modeling power generation equipment, planning the integration of power plants onto the electric grid, and performing generator control system parameter estimation.
Critical power system simulation and optimization tasks include:. Simulating performance against grid code and ensuring production goals are met Automating control system parameter estimation to meet regulatory requirements Performing EMT simulation and harmonic analysis to identify and mitigate power quality issues.
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