From GridLAB-D Wiki
pf_signed – Determines if a "signed" (leading/lagging) designation on the desired power-factor is accepted
Synopsis
module powerflow; class volt_var_control { bool pf_signed; } object volt_var_control { pf_signed value; }
Remarks
The value for pf_signed is used for setting whether desired_pf can have a sign associated with it. If pf_signed is enabled, desired_pf is set up as a positive value for a capacitive system (leading) and a negative value for an inductive system (lagging).
Default
The default value for pf_signed is false.