I. Introduction
One type of electrical equipment that converts direct current to alternating current is an in-line interactive converter. Alternating current that is equal to the output current from the mains must be produced by these appliances. In addition to monitoring voltage and frequency [1]–[4], interactive grid converters also need to monitor the phase, amplitude, and frequency of power lines. It is possible to install grid interactive inverters in residences with solar panels on the roof. The device converts the solar panels direct current energy into alternating current, which is the same current that the grid provides. If the power source is turned off, the voltage on the line can become zero [5]–[8].