Load-flow-analysis

Solving the load flow problem using Guass-Seidel iterative method. Written in C++.

3 Types of Buses

1. Slack bus or also known as swing bus.
2. PV bus or Gen bus.
3. PQ bus or Load bus.

Bus Input Data

Format for bus input data. Same is followed in the busInputData.csv file.

• All the data is in pu (per unit).
• '-' specifies that the data is unknown.

Type of Bus	V	δ degrees	Gen MW	Gen Mvar	Load MW	Load Mvar	Gen Mvar Max	Gen Mvar Min
1	1	0	-	-	0	0	-	-
3	-	-	0	0	8	2.8	-	-
2	1.05	-	5.2	-	0.8	0.4	4.0	-2.8
3	-	-	0	0	0	0	-	-
3	-	-	0	0	0	0	-	-

Line Input Data

• All the data is in pu (per unit).

From bus	To bus	R	X	G	B	Max MVA
2	4	0.0090	0.100	0	1.72	12
2	5	0.0045	0.050	0	0.88	12
4	5	0.00225	0.025	0	0.44	12
1	5	0.00150	0.02	0	0	6
3	4	0.00075	0.01	0	0	10

Steps used to solve the load flow problem

• Both the csv files are read and Y Bus matrix is constructed.
• Using the Y Bus matrix, iterative Guass-Seidel method is used to solve for voltages and δ.
• For PV bus, reactive power is calculated and if it exceeds its limits then the bus type is changed to PQ bus and new value of V is calculated for that bus.
• If the calculated value does not exceed its limits then only δ is computed for that bus.
• Finally P and Q are calculated for slack bus.
• Bus Data is updated and stored in output.csv.