Patent · US Expired

Control system for a linear synchronous motor

US4381478A · kind A · utility

52Cited by
4References
21Claims
0Family size

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Key dates

Filing dateMar 6, 1981
Grant dateApr 26, 1983
Priority date
Expiry dateMar 6, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/64
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

In a magnetic floating type of super high speed transportation system using a linear synchronous motor system as its drive system in which a field magnet is carried on a train and a series of armature coils are provided along a track, a speed of a train is regulated under control of a frequency converter of the variable frequency and voltage type for supplying power to the armature coils. For the speed regulation, a relative position of the field magnet to the armature coils is detected to form a train of position detecting pulses. A reference frequency pattern with a frequency corresponding to a speed command is formed. A phase difference between the reference frequency pattern and the position detecting pulse train is detected. A propulsion force command of a linear motor is obtained by setting different limit values in the positive and negative parts of the phase difference signal. A sinusoidal current waveform pattern is formed in synchronism with the position detecting pulse train. By multiplying the current waveform pattern by the propulsion force command, a sinusoidal armature current pattern is obtained of which the frequency and the crest value are fixed. The cycloconverte…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.