Modified amplitude-phase adaptive control in the pantograph-catenary vibration test system

This paper proposes a modified amplitude-phase adaptive control (MAPAC) for increasing the sinusoidal motion precision of the pantograph-catenary test system. Amplitude error, phase error and center position error of the sinusoidal signal are identified in the time domain. Through linear interpolation approach, phase lag time can be reduced to a smaller value than the system control period. Iterative sequences of the three parameters are established with error identification and an iteration rate for subsections is built with both the rapidity in low frequency and the stability in high frequency taken into account. The stateflow programs are divided into the identification and iteration sections. The experimental result for tracing errors using the pantograph-catenary vibration test system shows that the novel control strategy significantly improves the tracking accuracy of the sinusoidal test signal. It can be widely used in other engineering systems that require precision for tracing sinusoidal motions.