Development of the Low Noise Step Generator Based on the Resonant Royer Topology

The step generator is widely used in high voltage measurement techniques, i.e., step response measurement and PD calibrator. Step response measurement is a traditional method to characterize an impulse voltage divider, an impulse oscilloscope or a digital recorder, and PD calibrator has been applied for the calibration of a PD measuring system. Therefore, a low noise step generator should be designed and developed. This paper develops a low noise step generator whose voltage amplitude is 1kV, rising edge is less than 500ns, and the noise level is below 60mV. The step generator is composed of the high voltage DC power supply and the switch. The step voltage is produced by chopping the direct voltage using a solid MOSFET switch. Compared with flyback circuit, push-pull circuit, voltage doubling rectifier circuit and royer oscillation circuit, royer oscillation circuit is selected to design high voltage DC power supply by LTspice simulation. A solid MOSFET switch and its drive circuit are developed in this paper. The performance of the step generator is verified by the experiment, and the experimental results show that its voltage amplitude is 1.008kV, its rising edge is 408ns, and its the noise level is 54mV. Royer oscillation circuit and the solid MOSFET switch can be used to achieve the low noise step generator.