The capacitor model is basically implemented as a two-terminal power delivery element. However, if you don't specify a connection for the second bus, it will default to the 0 node (ground reference) of the same bus to which the first terminal is connected. That is, it defaults to a grounded wye (star) shunt capacitor bank.


These connection rules also apply to Vsource, Reactor, and Fault elements.



Figure 1: Definition of Capacitor Object


If you specify the connection to be "delta" then the second terminal is eliminated.


If you wish a series capacitor, simply specify a second bus connection.


If you wish an ungrounded wye capacitor, set all the second terminal conductors to an empty node on the first terminal bus, e.g.:


...Bus1=B1 bus2 = B1.4.4.4 ! for a 3-phase capacitor


Of course, any other connection is possibly by explicitly specifying the nodes.


While the Capacitor object is frequently treated as if it were a single capacitor bank, it is actually implemented as a multistep tuned filter bank. Many of the properties can be specified as arrays. See Numsteps property.


If you wish to represent a filter bank, specify either the XL or Harm property. When a Capcontrol object switches a capacitor, it does so by incrementing or decrementing the active step.