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Winter 2015: ECE666 Power Systems Operation Assignment-3

Submission due: Monday 6th April 2015, 4:30 PM -------------------------------------------------------------------------------------------------------------------------------- Question-1: A 4-area inter-connected power system is shown below. A transaction of 1000 MW takes place between two parties, injecting in area-1 and extracting in area-4. In each area, the flows on the limiting facilities, arising from this transaction, are shown in the parenthesis.

Area-1(5%)

Area-3(14%)

Area-2(10%)

20%

80%

15%

Area-4(11%)10%

90%

1000 MW

1000 MW

The available loading capacity (ALC) on each limiting facilities are given as under:

Facility ALC Facility ALC Area-1 70 MW Tie 1-2 400 MW Area-2 200 MW Tie 1-3 1200 MW Area-3 130 MW Tie 2-3 250 MW Area-4 175 MW Tie 2-4 200 MW Tie 3-4 900 MW

a. Determine if the above transaction is feasible. b. Otherwise determine the ATC for the interconnection, and which facility determines the

ATC value in this case. Question-2:

Area-A

Load = 3,500 MW

Generation = 3,000 MW

Area-B

Load = 6,000 MW

Generation = 6,500 MW

Consider a 2-area, 60 Hz system shown in the figure above. Area-A has a total load of 3500 MW and a generation of 3000 MW, and a total spinning reserve of 700 MW. Area-B has a total load of 6,000 MW, total generation of 6,500 MW and a total spinning reserve of 1000 MW. The following parameters are given:

D1 = 1%, D2 = 1.5%, R1 = 6%, R2 = 5%, B1 = 120 MW/0.1Hz, B2 = 200 MW/0.1Hz. Find the steady state frequency, generation and load in each area and tie-line power for the following cases: i. A sudden decrease of 100 MW load in Area-A when the system is only on primary regulation.

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ii. Loss of 100 MW load in Area-A. The units carrying spinning reserve in each area are on AGC. Question-3: Consider the 3-area, 60 Hz system, shown below. a. Find the scheduled interchange between the three areas. b. There is a sudden load interruption of 500 MW in Area-1. All the three systems are on

primary regulation only. Find the operating condition of each area (tie line flows, steady-state frequency, generation and load condition) after the disturbance.

Area-1 Load = 5,000 MW

Generation = 5,700 MW Spinning Reserve = 500 MW

R = 5%, D = 1%

Area-2 Load = 9,600 MW

Generation = 9,200 MW Spinning Reserve = 600 MW

R = 6%, D = 2%

Area-3 Load = 7,600 MW

Generation = 7,300 MW Spinning Reserve = 400 MW

R = 6%, D = 1.5%

Question-4: Utility-A has there generators Gen-1, Gen-2 and Gen-3 whose generating capacity and forced outage rates (FOR) are given as under:

Capacity,

MW FOR Innage

Gen-1 200 0.05 0.95 Gen-2 250 0.03 0.97 Gen-3 400 0.04 0.96

Determine the cumulative outage probability table and hence the LOLP using the convolution algorithm for a load of (i) 700 MW (ii) 650 MW and (iii) 750 MW. Question-5: A second utility (B) with an identical cumulative outage probability table is interconnected to A via a tie line of 100 MW capacity. The load of A is 800 MW, while that of B is 730 MW. Both utilities are required to maintain an operating reserve equivalent to 5% of their system demand at all times. Determine the LOLPs of the two utilities after the interconnection.