Steady State Power Flow Calculations

1. Steady State Power Flow Calculations Kevin Schneider, Chen-Ching Liu University of Washington Department of Electrical Engineering

2. Power Flow Information • Method used: Newton-Raphson Assumptions: 1) Constant voltage at the shore stations 2) Constant direct current power loads 3) Constant system topology

3. Convergence Criteria • Sum of the differences of all node voltages between two iterations Example: Total Difference= .2+.3+.2+.1+.4= 1.2V

4. Voltage Collapse • If PL exceeds the point of maximum power transfer the powerflow solution will not converge. • Operation beyond the Maximum Power Transfer Region must be avoided

5. Sample Power Flow Calculations • Using the shown network topology 1) All nodes at 2.65 kW 2) All nodes at 4.3 kW 3) All nodes at 4.8 kW

6. Results 1: 2650Watts per Node

7. Results 2: 4300 Watts per Node

8. Results 3: 4800 Watts per Node Voltage collapse occurs; the powerflow solution does not converge

9. Questions?