Harmonic emission in range of 2-50 kHz (Supra-Harmonic) is a new threat to the operation of power grids which can result in capacitors failure, interruption in telecommunication systems, network automation, wireless communications and increased error in measurement equipment. Increase in capacitive behavior and decrease in load impedance will make high frequency flow from nonlinear loads to load capacitance component of the network. In terms of harmonics production resources, the capacitance component is parallel to short-circuit impedance of the network (X/R)). Depending on short-circuit impedance of the network (X/R), the function of load capacitance component can be low-pass or intermediate filter. In this paper, it is tried to investigate the effect of increase in loads capacitance component of network on high frequency oscillation rate (2-150 kHz) due to switching of full power converter. The static converter used in this simulation is a two-level back-to-back converter (6 pulses) and a 2000-Hz full-power converter's switching frequency. The load capacitance component of network is considered at three levels of low capacitor (1kVar), medium capacitor (2.5kVar) and high capacitor (5kVar). The harmonic and spectrogram STFT analysis of network's currents, resistance- inductance capacitance component with sampling time (Sample time = 50 microseconds) has been performed in Matlab. The results indicate that in low capacitance components, the system acts as an intermediate pass filter (9-10 kHz). In medium capacitance component, the system operates in the form of high cutoff intermediate pass filter (6-7 kHz). The behavior of system in the high capacitance component is as an intermediate pass filter of cut-off frequency 4-5 kHz. The results show that by increase in the load capacitance capacity, although the number of high frequency harmonic components has decreased, the size of the high-frequency harmonics released to the network and the load resistance- inductance component have increased.