Purpose/Aim
Temperature drift, stress birefringence and low frequency vibration lead to the randomness and fluctuation of the output of optical voltage sensor. In order to solve the problem, this study adopts the phase-locking amplification modulation technology, with the aid of a high-speed rotating electrode to realize high frequency electric field modulation. The electrical filed modulation technology will shift the measured signal frequency spectrum window from ~50 Hz moved to ~ 1 KHZ, so as to make the output signal avoid the interference from the low temperature drift, stress birefringence and vibration interference, leading to higher stability and reliability.
Experimental/Modeling methods
The electro-optic coupling wave theory and static electric field finite element method are used in the simulation. The finite element method is used to analyze the crystal electric field induced by multi-quadrant heterogeneous electrode at different rotation angles. Coupling wave theory is utilized to calculate the electro-optical output signal for certain electric field distribution. The simulation results proves that if electric field modulation can be realized by multi-quadrant heterogeneous electrode, which is driven by PWM and DC motor.
Results/discussion
The simulation results show that the electric potential and electric field distribution of the optical path are regulated by the rotating isomeric electrodes, lead to a modulation of the electro-optical output signal. This is consistent with our groups’ previous results, namely, the half-wave voltage and photo signal sensitivity of crystal can be regulated by using centrosymmetric isomeric electrode.
Conclusions
In this study, an optical voltage sensor design based on rotating heterogeneous electrode is proposed. Simulation results show that multi-quadrant electrode can regulate the electric field of the optical path. This design is expected to solve the randomness and fluctuation drift of measurement results caused by temperature drift, stress birefringence and low-frequency vibration. The experiment would be conducted in the future.
 

optical voltage sensor,modulation,isomerism electrode