CONTROL SIGNAL MODULATION CIRCUIT, INVERTER, AND CONTROL SYSTEM

A circuit for modulating a control signal, an inverter and a system for controlling a photovoltaic string. The circuit is based on a DC/DC boost circuit. The DC/DC boost circuit includes a controllable switch circuit, via which a second capacitor charges a first capacitor in the DC/DC boost circuit. A switch state of a first controllable switch in the DC/DC boost circuit is controlled when a voltage of the first capacitor is greater than or equal to a first voltage threshold, so that the first capacitor generates a control signal with a predetermined characteristic waveform.