Switch

Switch objects are used to change topology and add or remove elements from a powerflow system. When a switch is opened, no current flow is permitted and the downstream objects will be effectively removed from the system. Further details on switch behavior can be found in the switch section of the theory page. A typical switch implementation is

object switch {
    name switch1;
    phases ABCN;
    from node_250;
    to node_243;
    status CLOSED;
    }

Switch Parameters

Properties

The switch objects are derived from link objects, so any parameters of the link object are available as well. Notably the status property is inherited from the link class and can be used to open or close all phases of the switch. The switch class also adds additional properties to control the state of each phase individually, as well as the impedance of the switch when closed.

The I/O column indicates whether a property is user-settable input (I), simulation-computed output (O), or both (IO).

Table 1: switch table 1

Property Name	Type	Unit	I/O	Description
phase_A_state	enumeration	N/A	IO	Status of the phase A portion of the switch. Valid states are: - OPEN - switch is open and no current can flow - CLOSED - switch is closed and conducting
phase_B_state	enumeration	N/A	IO	Status of the phase B portion of the switch. Valid states are: - OPEN - switch is open and no current can flow - CLOSED - switch is closed and conducting
phase_C_state	enumeration	N/A	IO	Status of the phase C portion of the switch. Valid states are: - OPEN - switch is open and no current can flow - CLOSED - switch is closed and conducting
operating_mode	enumeration	N/A	IO	Switching operations governing criterion. Two settings are available: - INDIVIDUAL - each phase of the switch object is controlled individually. - BANKED - all valid phases of the switch object are controlled together. A voting scheme of valid phases is used to determine this. For example, if a switch has phases A, B, and C with only phase C closed, phase A and B will override it and open phase A.
switch_impedance	complex	Ohm	I	Impedance value of the switch when closed
switch_resistance	double	Ohm	I	Resistance portion of impedance value of the switch when it is closed.
switch_reactance	double	Ohm	I	Reactance portion of impedance value of the switch when it is closed.

Switch State of Development

Switch is considered a well developed and validated model in terms of powerflow solutions, however, models incorporating fault analysis, reliability, and other advanced features have not been validated.