A Low-noise and Compact Very Low Frequency Sinusoidal Generator

In this letter, a novel very low frequency sinusoidal (VLF-sin) generator is proposed and established based on rectification circuit and power amplifier. A sinusoidal signal with a high frequency of 10kHz and a amplitude varying between 0 and 5V is generated by the Field Programmable Gate Array (FPGA). The voltage level and power of the signal are amplified by a power amplifier and transformer. Through the rectification circuit, a low-noise high-voltage (HV) VLF-sin waveform can be generated. The voltage can be applied to partial discharge (PD) detection because there is no noise from the switching device. Finally, a simulation verification is carried out to prove the feasibility of the generator.