Power Transmission on the Line

The power transmission on the line can be determined by analyzing the voltage and current at the midpoint of the transmission line, where the STATCOM is installed.

Given Information:
- Midpoint voltage (Vm) = 1 pu (per unit)
- Power angle (δ) = 400
- Source voltage (Vs) = 1 pu
- Receiving voltage (Vr) = 1 pu
- Section reactor impedance (Z) = 0.5 pu

Calculating Current Drawn by STATCOM:
To determine the current drawn by the STATCOM, we can use the formula:

Istatcom = (Vs - Vr) / Z

Substituting the given values, we get:

Istatcom = (1 - 1) / 0.5 = 0 pu

This means that the STATCOM does not draw any current.

Calculating Power Transmission on the Line:
The power transmission on the line can be calculated using the formula:

Ptransmission = Vm * Vr * sin(δ) / Z

Substituting the given values, we get:

Ptransmission = 1 * 1 * sin(400) / 0.5 = -0.909 pu

The negative sign indicates that the power is flowing in the opposite direction as compared to the reference direction.

Explanation:
- The STATCOM is installed at the midpoint of the transmission line to regulate the midpoint voltage (Vm) to 1 pu.
- The power angle (δ) of 400 indicates the phase difference between the source voltage (Vs) and receiving voltage (Vr).
- The section reactor impedance (Z) of 0.5 pu represents the line impedance between the STATCOM and the receiving end of the transmission line.
- The current drawn by the STATCOM is determined by the voltage difference between the source and receiving ends divided by the impedance.
- In this case, the current drawn by the STATCOM is zero, indicating that it does not consume any current.
- The power transmission on the line is calculated using the formula, considering the midpoint voltage, receiving voltage, power angle, and line impedance.
- The calculated power transmission is -0.909 pu, indicating that power is flowing in the opposite direction as compared to the reference direction.

Overall, the STATCOM installation and regulation of midpoint voltage help in maintaining the desired power transmission on the line by compensating for reactive power and controlling voltage levels.