CIM Issues #5099
Since variable shunt compensator cannot be linear because g=Re(1/(r+jx)) it is enough to specialize the NonlinearShuntCompensator class. Proposed note for the specialized class VariableShuntCompensator: A variable shunt compensator is a oil-filled reactor with discrete on-line regulation of reactive power. The regulation range typically varies between 30% and 100% of rated reactive power. When energized VSR cannot have a reactive output of 0 Mvar, so minimal valid section number is 1 with reactive power output at either 100% or minimal reactive power output (reactive power can raise or fall with increasing section number).