Pspice Project
Abstract
In our experiment, we analysed three-phase balanced or unbalanced circuits by using PSpice 9.1 and the same way is used to analyse single-phase ac circuit. We determined the value of generator current Iab, line current IbB, and the phase current IBC. Initially, PSpice is used to draw a schematic diagram of circuit A. Under the simulation, two major problems were occurred. First, a delta connected source is a loop of voltage sources which must be prevented when PSpice is used. To prevent this, we connect a resistor of negligible or very low value of resistance of the resistor into each phase of delta-connected source. Second, the delta-connected source did not provide a node for ground node to run the simulation. Therefore, we inserted wye-connected large value resistor in the delta-connected source so that it can be served as ground. This means that in Circuit 1, a resistor of negligible or very low value of resistance is connected into each phase of delta-connected source.
Figure 1: Circuit 1
Content
No
Title
Page
1
Introduction
1
2
Methods
2-4
3
Results
5-12
4
Discussion and Conclusion
13
5
Reference
14
Introduction Three-phase system refer to a system consist of three voltage sources connected to loans by three or four wires and is equivalent to three single-phase circuits. The voltage sources can be either wye-connected or delta-connected. Three phase voltages are often produced with a three phase ac generator which basically consists of a rotating magnet or rotor surrounded by a stationary winding (stator). Three separate windings or coils with terminals are physically placed 120o apart around the stator. Since the three-phase voltages are 120o out of phase with each other, there are two possible combination. One is known as positive sequence. This sequence is produced when the rotor rotates counter clockwise. The other is known as negative sequence and is produced when the rotor rotates in
In our experiment, we analysed three-phase balanced or unbalanced circuits by using PSpice 9.1 and the same way is used to analyse single-phase ac circuit. We determined the value of generator current Iab, line current IbB, and the phase current IBC. Initially, PSpice is used to draw a schematic diagram of circuit A. Under the simulation, two major problems were occurred. First, a delta connected source is a loop of voltage sources which must be prevented when PSpice is used. To prevent this, we connect a resistor of negligible or very low value of resistance of the resistor into each phase of delta-connected source. Second, the delta-connected source did not provide a node for ground node to run the simulation. Therefore, we inserted wye-connected large value resistor in the delta-connected source so that it can be served as ground. This means that in Circuit 1, a resistor of negligible or very low value of resistance is connected into each phase of delta-connected source.
Figure 1: Circuit 1
Content
No
Title
Page
1
Introduction
1
2
Methods
2-4
3
Results
5-12
4
Discussion and Conclusion
13
5
Reference
14
Introduction Three-phase system refer to a system consist of three voltage sources connected to loans by three or four wires and is equivalent to three single-phase circuits. The voltage sources can be either wye-connected or delta-connected. Three phase voltages are often produced with a three phase ac generator which basically consists of a rotating magnet or rotor surrounded by a stationary winding (stator). Three separate windings or coils with terminals are physically placed 120o apart around the stator. Since the three-phase voltages are 120o out of phase with each other, there are two possible combination. One is known as positive sequence. This sequence is produced when the rotor rotates counter clockwise. The other is known as negative sequence and is produced when the rotor rotates in