Alternating current and direct current voltage detection method and device for inhibiting optical voltage transducer nonlinear characteristic

Abstract

The invention discloses an alternating current and direct current voltage detection method and device for inhibiting an optical voltage transducer nonlinear characteristic. Considering that a closed loop error signal has a nonlinear characteristic and is easily influenced by disturbance of an external environment, an output of a photoelectric detector is pre-processed, square waves of the nonlinear closed loop error signal are modulated, and the frequency of the error signal is migrated to a high frequency region. The error signal is extracted through a band-pass filter in an undistorted mode, and white noise of the output of the photoelectric detector is filtered. An output signal of the band-pass filter is converted into a digital signal and is demodulated into low-pass filter. A system state equation is established, and the stability of the system state equation is controlled, so that the indicial response decay speed of the error signal is recovered to be a zero balance point, specified noise suppression level is met, the influence of the nonlinear characteristic to the closed loop performance of an optical voltage transducer system is inhibited, a dynamic measurement range of direct current voltage and the bandwidth width are widened, and a dynamic response characteristic of the system is improved.

Description

technical field [0001] The invention belongs to the technical field of optical voltage transformers, in particular to an AC / DC voltage detection method and a detection device for suppressing the nonlinear characteristics of optical voltage transformers. Background technique [0002] The optical voltage transformer uses the closed-loop detection method and the square wave modulation technology to make the system work at the zero phase point. Its advantages are high sensitivity, good linearity and wide dynamic range. [0003] The closed-loop optical voltage transformer adopts square wave modulation and ladder wave feedback technology, which suppresses the influence of optical power fluctuations to a large extent and expands the dynamic range of the system. However, the system is still a nonlinear system, and its nonlinearity affects the performance of the optical voltage transformer, and the optical voltage transformer is easily affected by the disturbance of the external envi...

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