68 / 2022-03-09 17:10:07

A Novel CT-Based Power Tapping Design Adapting to Extreme Current Fluctuation

multi-port CT,power tapping,current transformer (CT),on-line monitoring devices

With the wide application of on-line monitoring devices for power system, the current transformer (CT) energy extraction has received extensive attention. Whether the current of the transmission line is too high or too low, it makes the CT unable to supply energy reliably. Aiming at this problem, the CT with adjustable output is designed to adapt to current fluctuation in this paper.

Experimental/Modeling methods

The design in the paper consists of three parts: the multi-port CT, energy conversion module and rechargeable battery. First, inspired by the multi-connector transformer in the power system, the CT output ports are set to three. The port position of CT and switch control strategy are carefully designed to achieve high reliability of the system. And the two terminals with the maximal output voltage are connected directly by resistor. Its resistance is set to minimize the power loss of CT. Second, the AC/DC module ensures that the AC obtained by CT is converted into stable output DC. Then the operation strategy of rechargeable battery is clarified. Finally, A simulation in Matlab is implemented to verify the feasibility of the proposed design.

Results/discussion

The introduction of multi-port CT enhances the power supply capability for monitoring devices under extreme current conditions, while the use of rechargeable battery can cope with the situation of no current in the transmission line. This design can realize the safe and reliable power supply for monitoring devices.

Conclusions

The introduction of a multi-port CT with well-designed port parameters can greatly improve the ability of power tapping of CT to cope with extreme current amplitudes.