METHOD OF SPECTRAL ANALYSIS OF PERIODIC MULTIPLE FREQUENCY SIGNALS CONTAINING INTERHARMONIC AND PRESET WITH DIGITAL READING Russian patent published in 2008 - IPC G01R23/16 

FIELD: physics.

SUBSTANCE: invention can be used to evaluate spectral composition of periodic multiple frequency signal containing interharmonics and preset with digital reading. For pickup signal a(t_i) preset by instantaneous value reading, for sequence of frequencies ω₁,ω₂,... ω_j, ...ω_n instantaneous spectral density is evaluated. Then characteristic extremes of instantaneous spectral density distribution is evaluated by condition at frequency S (ω). Frequencies ω_j of pickup signal a(t_i) are evaluated by extreme points. By computed frequencies, amplitude is evaluated; pickup signal component phase is evaluated due to series reference signal b₀ (t_j) =B_msin (ω₀t_j+ϕ₀) at frequency ω₀=ω_k. Voltage-current characteristic a(b₀) is plotted for pickup signal a(t_i), multiply dephased while evaluating voltage-current characteristic area F_BAX (ϕ₀ = -180°...+180°), phase of each signal frequency component ϕ_k is calculated by condition F_BAX≅0, further computed values Am_j, ω_j, ϕ_j indicate spectral composition of pickup signal a(t_i).

EFFECT: invention expands range of technical equipment of similar purpose.

3 dwg, 2 tbl