Abstract
Online detection and classification of changing harmonic signal content are common issues in vehicle control, both regarding mechanical and electrical oscillations. This paper presents an overview of the most recent patents. In particular it shows an invention in which a fast and numerically efficient method is used. The well known signal correlation principle is applied to detect, in real time operation, instantaneous dominant oscillations in a time-varying (temporally-variant) harmonic signal.
Keywords: Oscillations detection, pantograph control, Oscillations, harmonic signal, electrical oscillations, velocity controller, electropneumatic system, electric-powered vehicles, rail vehicles, tramway vehicles, trolley vehicles, piezoelectric mounting leaf spring, servo motor control apparatus, pneumatic control, pantograph device, Contact stripes, particular transient, connection point, Vertical low-frequency vibrations (LF-V), Horizontal high-frequency movements (HF-H), quasiharmonic signal, funnel filters, Heisenberg indetermination principle, long time window, drop-off effect, black region, PID regulator, pantograph pressure, denoising algorithm, actuator-pantograph, trigonometric functions, quadratic sum, dominant frequency, threshold level, Matlab platform, Digital Signal Processor (DSP), trigonometric wavelets, VALIDATION AND SIMULATIONS, sub-harmonics, very large black regions, drop off, simulated signal, wavelet packets