For the convenience of energy harvesting of on- line monitorign signal of capacitor and overcoming such shortcomings as high power consumption

serious heating and complex structure of existing energy harvesting coil

in this paper the DC-side magnetic flux compensation technology is used to develop a small and low-power energy harvesting coil for capacitor monitoring. Firstly

the relationship among the maximum power and power consumption of the energy harvesting coil

and its size s well as load is analyzed. The magnetic flux compensation scheme on the DC side is proposed

which forms a magnetic flux compensation circuit through voltage limiting capacitor

anti-reverse diode

hysteresis comparator and a full-bridge rectifier to dynamically achieve compensation of the main magnetic flux of the coil. Thus

the energy harvesting can be made in a large primary current range with a small area of the magnetic core without special heat dissipation design. Then

the effect of the scheme is verified by PSPice simulation

the circuit design and testing are performed further and the test result and simulation result are in agreement. The designed scheme has a wide application prospect.