A new removable 5th harmonic voltage transformer using a bridge-connected three-leg magnetic circuit

Abstract Aiming at the harmonic resonance problem of photovoltaic inverter cluster system when it is incorporated into weak power grid, an active damper frequency division control method is proposed to suppress the harmonic resonance. Firstly, the voltage signal measured by the voltage transformer is separated according to the frequency, and then the harmonic conductance value of the frequency band is controlled respectively according to the harmonic voltage. Finally, the output current is feedback controlled by the generalized integral PI controller, so as to realize the impedance remolding of the photovoltaic inverter cluster system. This method can adjust the value of virtual conductance in different frequency band adaptively according to the harmonic voltage, so as to suppress the harmonic resonance problem of photovoltaic inverter cluster more effectively. The simulation results of Matlab/Simulink demonstrate the correctness and effectiveness of the proposed frequency division control method.

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Magnetic Circuit of a High-Voltage Transformer up to 10 kHz

IEEE Transactions on Magnetics ◽

10.1109/tmag.2014.2357784 ◽

2015 ◽

Vol 51 (1) ◽

pp. 1-4 ◽

Cited By ~ 14

Author(s):

Radek Prochazka ◽

Jan Hlavacek ◽

Karel Draxler

Keyword(s):

High Voltage ◽

Magnetic Circuit ◽

Voltage Transformer ◽

High Voltage Transformer

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Harmonic voltage measurement error of the capacitor voltage transformer

PLoS ONE ◽

10.1371/journal.pone.0205231 ◽

2018 ◽

Vol 13 (11) ◽

pp. e0205231 ◽

Cited By ~ 1

Author(s):

Jian Le ◽

Hao Zhang ◽

Chao Gao ◽

Qian Zhou

Keyword(s):

Measurement Error ◽

Voltage Measurement ◽

Voltage Transformer ◽

Capacitor Voltage ◽

Harmonic Voltage

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A New Bridge-Type Transformer Using a Three-Leg Core and Its Application to a Removable 5th-Harmonic Voltage Transformer.

Journal of the Magnetics Society of Japan ◽

10.3379/jmsjmag.23.1493 ◽

1999 ◽

Vol 23 (4−2) ◽

pp. 1493-1496

Author(s):

S. Okanuma ◽

K. Terauchi ◽

A. Hayasaka ◽

O. Ichinokura

Keyword(s):

Voltage Transformer ◽

Bridge Type ◽

Harmonic Voltage

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ON APPLICATION OF AMORPHOUS STEELS IN THE MAGNETIC CIRCUITS OF VOLTAGE TRANSFORMERS

Vestnik Chuvashskogo universiteta ◽

10.47026/1810-1909-2020-3-58-66 ◽

2020 ◽

pp. 58-66

Author(s):

Lyudmila V. Bykovskaya ◽

Viktor V. Bykovskiyi

Keyword(s):

Mathematical Model ◽

Finite Element Method ◽

Amorphous Alloys ◽

Magnetic Circuit ◽

Graphical Representation ◽

Nonlinear Differential Equations ◽

The Finite Element Method ◽

Voltage Transformer ◽

Magnetic Circuits ◽

Magnetic Induction Distribution

The article presents the results of studying the influence of amorphous steels on the antiresonance properties of voltage transformers. The authors developed a mathematical model of a voltage transformer with a magnetic circuit using amorphous steels based on the system of nonlinear differential equations with approximation of the magnetization curve of steel by a hyperbolic expression. The model was applied to the calculation of a voltage transformer with different brands of amorphous alloys. The model of the anti-resonance voltage transformer based on the finite element method and created with the help of the FEMM PC was used to verify the obtained results which made it possible to obtain a graphical representation of magnetic induction distribution in the voltage transformer magnetic circuit.

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Effects of contact gap on nondestructive evaluation using magnetic measurement for ferromagnetic steel

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209411 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 969-975

Author(s):

Hiroaki Kikuchi ◽

Yuki Sato

Keyword(s):

Magnetic Flux ◽

Nondestructive Evaluation ◽

Effective Permeability ◽

Magnetic Circuit ◽

Magnetic Measurement ◽

Air Gap ◽

Motive Force ◽

Hysteresis Curve ◽

Evaluation Technique ◽

Ferromagnetic Steel

We investigated effects of contact gap on magnetic nondestructive evaluation technique using a magnetic single-yoke probe. Firstly, we evaluated hysteresis curves and impedance related to permeability of the material measured by a single-yoke probe, when an air gap length between the probe and specimens changes. The hysteresis curve gradually inclines to the axis of the magneto-motive force and magneto-motive force at which the magnetic flux is 0 decreases with increasing the gap length. The effective permeability also decreases with increasing the gap thickness. The incremental of gap thickness increases the reluctance inside the magnetic circuit composed of the yoke, specimen and gap, which results in the reduction of flux applying to specimen.

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Analysis of magnetic force and dynamic characteristic for non-contact permanent magnet linear drive device

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209452 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 1337-1345

Author(s):

Chuan Zhao ◽

Feng Sun ◽

Junjie Jin ◽

Mingwei Bo ◽

Fangchao Xu ◽

...

Keyword(s):

Finite Element ◽

Permanent Magnet ◽

Dynamic Characteristic ◽

Driving Force ◽

Magnetic Circuit ◽

Response Speed ◽

Computation Method ◽

Element Analysis ◽

Element Simulation ◽

The Relationship

This paper proposes a computation method using the equivalent magnetic circuit to analyze the driving force for the non-contact permanent magnet linear drive system. In this device, the magnetic driving force is related to the rotation angle of driving wheels. The relationship is verified by finite element analysis and measuring experiments. The result of finite element simulation is in good agreement with the model established by the equivalent magnetic circuit. Then experiments of displacement control are carried out to test the dynamic characteristic of this system. The controller of the system adopts the combination control of displacement and angle. The results indicate that the system has good performance in steady-state error and response speed, while the maximum overshoot needs to be reduced.

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