Economic load dispatch and unit commitment (cost control)

In a two plant system the load is connected to plant number two the loss coefficient.

• B11,B12,B22 are nonzero

• B11 is nonzero but B12 and B22 are zero

• B11 and B12 nonzero but B22 is zero

• B11 and B22 nonzero but B12 is zero

If the penalty factor of a plant is unity, its incremental transmission loss is

• 1.0

• -1.0

• Zero

• None any of these

economic operation of power system is carried out on the basis of

• Equal incremental fuel cost

• Equal area criterion

• Equal fuel cost criterion

• All units sharing equal power

Unit commitment is

• A must before we solve economic operation problem

• A short term problem of maintenance scheduling

• More meaningful for thermal units

• All option correct

For short term planning problems losses can be found out.

• By using approximate loss formula

• By load flow studies

• By carrying out stability studies

• Can be ignored

For long term hydrothermal problem

• Head variation can be ignored

• Transmission loss cannot be ignored

• Unit commitment should be taken into account

• All the answers

for economic operation The generator with highest positive incremental transmission loss will operate at

• the highest positive incremental cost of production

• the highest negative incremental cost of production

• the lowest positive incremental cost of production

• the lowest negative incremental cost of production

A two bus system has loss co-efficient as

• B11=0.03 B22=0.05 B12=0.001 B21=-0.001

• B11=0.03 B22=0.005 B12=-0.001 B21=-0.001

• B11=0.02 B22=0.04 B12=-0.01 B21=0.001

• B11=0.02 B22=0.05 B12=0.01 B21=0.015

Solve this

• Pg1=350/3 MW and Pg2=400/3 MW

• Pg1=100 MW and Pg2=250 MW

• Pg1=125 MW and Pg2=125 MW

• Pg1=150 MW and Pg2=100 MW

Two plants generates power as given below. Pg1=50 MW and Pg2=100 MW,respectively.if the loss coefficient of the two plants are given as B11 = 0.002, B22 = 0.0015, B12 =-0.0011.the power lost will be

• 20 MW

• 15 MW

• 18 MW

• 22 MW