What is the term for generators supplying VARs to support voltage and operating in that mode?

The term for generators supplying VARs (Volt-Ampere Reactive) to support voltage while operating in that mode is recognized as "lagging." When a generator operates in a lagging mode, it is providing reactive power to the system, which is crucial for voltage support. This occurs because the generator is effectively supplying reactive power to the grid, thereby helping to stabilize voltage levels and improve power factor, which is necessary for maintaining the reliability and efficiency of the electric power system.

In this context, a generator supplying VARs reflects a situation where current lags behind voltage, typical of inductive loads. This is why the term “lagging” is specifically associated with generators or devices that provide this kind of reactive power support.

The other terms offered, such as "leading," refers to a condition where current leads voltage—an opposite scenario usually related to capacitive loads. "Inductive" generally describes the nature of loads that consume reactive power, and "reactive" merely describes the power type itself without context to the operational mode of the generator. Therefore, the term "lagging" accurately characterizes the situation where generators are supplying VARs to support voltage.