Title:
DEFECT DETECTOR FOR THYRISTOR
Document Type and Number:
Japanese Patent JPS5843175
Kind Code:
A
Abstract:
PURPOSE:To detect the number and position of defects of a thyristor by connecting light emitting elements which emit lights of different wavelengths in parallel with a plurality of thyristors connected in series with each other, and individually detecting the wavelengths of the generated lights. CONSTITUTION:Dividing resistors 15-18 and diode bridges 19-22 are connected parallel to a plurality of thyristors 2-5 connected in series with a thyristor valve or the like, visible or infrared ray lights are generated at the DC sides of the bridges 19-22, and are connected with light emitting elements 23-26 having different peak emitting light wavelengths. The generated lights are fed through light guide 31 to a branching filter 32, which individually dividing the wavelengths to detect them by detectors 33-36. Since the light of the wavelength corresponding to the defective thyristor is not accordingly detected, the number and position of the defective thyristors can be effectively detected.
Inventors:
IYOTANI RIYUUJI
KONISHI HIROO
SHIRAHAMA HIDEFUMI
KONISHI HIROO
SHIRAHAMA HIDEFUMI
Application Number:
JP13845981A
Publication Date:
March 12, 1983
Filing Date:
September 04, 1981
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G05B23/02; H02M1/00; H02M1/092; H03K17/10; H03K17/73; (IPC1-7): G05B23/02; H02M1/18; H03K17/10; H03K17/72
Attorney, Agent or Firm:
Akio Takahashi