The invention discloses a pulse signal generator and a control method, and belongs to the technical field of rail transit automation control. The pulse signal generator mainly comprises a control circuit, a boosting circuit, a feedback circuit and a capacitor, an input terminal of the boosting circuit is connected with an output terminal of the control circuit, an output terminal of the boosting circuit is connected with the capacitor, an input terminal of the feedback circuit is connected with the boosting circuit, and an output terminal of the feedback circuit is connected with the control circuit. According to the pulse signal generator and the control method, PWM signals for outputting a variable duty ratio are adopted to control the on-off time proportion of a transformer, uniform increase of the energy storage duty ratio of the transformer is realized, and uniform increase of the voltage of an output terminal of the transformer is realized; after completion of charging of the capacitor, the voltage is kept stable, and the fluctuation range can be controlled in the range from -1% to +1%; and the charging voltage can meet the requirements in the condition of different frequencyrequirements.