Network node (bus)
[Transmission flow solver (network)]


Detailed Description

The node object implements the general node solution elements of the Gauss-Seidel solver.

The types of nodes are supported

Three bus types are supported, PQ, PV, and SWING:

PQ bus

The PQ bus is the most commonly found bus type in electric network models. PQ buses are nodes where both the real power (P) and reactive power (Q) are given. In these cases, the updated voltage at for a node is found from an existing (non-zero) voltage using

\[ \widetilde V \leftarrow \frac{P - \jmath Q}{\widetilde{YY} \left( \widetilde V^* - \Sigma \widetilde{YV} \right)} \]

where

\[ \widetilde{YY} \leftarrow \Sigma \widetilde Y + G + \jmath B \]

PV bus

The PV bus is the next most common bus type in electric network models. PV buses are nodes where the real power (P) is given, but the reactive power (Q) must be determined at each iteration. In these cases, the updated voltage for a node is found by calculating

\[ Q \leftarrow - \Im \left[ \widetilde V^* \left( \widetilde{YY} \widetilde V + \Sigma \widetilde{YV} \right) \right] \]

If Q exceeds the Q limits [Qmin, Qmax] then the angle is fixed to the correspond limit and the bus is solved as a PQ bus.

SWING bus

The SWING bus occurs at least one in any given island of a network models. Large models may have more the one SWING bus, particularly if areas of the network are only lightly coupled by relatively high impedance links. SWING bus nodes are nodes where both the real power (P) and reactive power (Q) must be determined at each iteration. In these cases, the updated voltage for a node is found by

\[ \widetilde S \leftarrow \left[ \widetilde V^* \left( \widetilde{YY} \widetilde V + \Sigma \widetilde{YV} \right) \right] \]

where

\[ P + \jmath Q \leftarrow \widetilde S \]


Modules

 Load
 Load objects represent static loads and export both voltages and current.
 Pqload
 Load objects represent static loads and export both voltages and current.


GridLAB-DTM Version 2.0
An open-source project initiated by the US Department of Energy