Assumption of decoupling is valid only if
Assumption of decoupling is valid in load flow study only if resistance of the line is negligible in comparison to the reactance of the line.
In a load flow solution Vi = 1.083∠150 pu and Vk = 0.986∠-20 pu. What is the direction of active power (P) and reactive power (Q) flow in the line i - k?
Since active power flows from leading bus to lagging bus therefore, P will flow from i to k.
Since, reactive power flows from high potential bus to low potential bus therefore, Q will flow from i to k.
The slack bus has to be a
Out of the 15% of Generator buses in a power system, one bus is taken as a slack bus which take care of losses occuring in the system. At a generator bus P and V are known. Hence, a slack bus can be a PV bus.
Providing synchronous condensers at a load bus will control
A synchronous condeser regulates Q and thus controls power factor of the system.
Generally in load flow solutions the load is modelled as a
At a slack bus
The complex power injections at a bus are as shown below. Two lines are connected drawing powers as shown in figure below. Sx is
When the bus voltage magnitudes at the two ends of a transmission line are equal, if the line is lossless, then Sij is related to Sji by which of the following relationships? (Sij is complex power from bus i to j)
If S = VI*, P is positive and Q is negative, the network is
Given, S = ( P - j Q )... for given network
Since P is positive, therefore the given network absorbs P.
Since Q is negative, therefore the given network absorbs -Q or delviers +Q.
In a power system with 100 buses, 1 bus is taken as slack bus, 15 buses are P\/ buses and rest are PQ buses. The number of variables to be solved by NR method in polar coordinates is
Hence, number of variables to be solved by NR method in polar coordinates = 183.