Page 411 - Decision Making Applications in Modern Power Systems

372 Decision Making Applications in Modern Power Systems

FIGURE 14.3 PPL determination algorithm. PPL, Permissible penetration level.

2. Measuring the loss under the existed unbalanced and distorted supply volt-
age, hence equalizing the measured one to the rated loss by reduction of
the loading ratio.
3. Measuring the highest rms stator phase current under the existed unbal-
anced and distorted supply voltage, hence equalizing the measured one to
the rated current by reduction of the loading ratio.

In this work, to find the highest permissible active power (P Gmax ) of the
IGs under voltage unbalance and harmonic distortion conditions, whose
mechanical input power is adjusted by pitch control, the highest stator phase
current (I Gmax ) is intentionally reduced to the rated current (I GR ). Hence,
PPL is found as follows:

P Gmax
PPL %ðÞ 5 3 100 ð14:21Þ
P GR
where P GR is the rated active power of the IGs. The flowchart of the PPL
determination algorithm is shown in Fig. 14.3.

14.2.3 Modeling of the Steinmetz compensator

The three-phase equivalent circuit of the SC is shown in Fig. 14.4. In this
figure the SC’s admittances are denoted as