Results 191 to 200 of about 27,637 (228)

Nonsinusoidal power caused by measurements of grid impedances at unbalanced grid voltages

2008 International School on Nonsinusoidal Currents and Compensation, 2008
At low-voltage level there is already a commercial measurement device that is able to identify the grid impedance in dependency of time and frequency. Since at the low-voltage level a four-wire system and at the medium-and high-voltage level a three-wire system is installed, the method to identify the grid impedance has to be varied.
null Trung Do Thanh, Steffen Schostan, Klaus-Dieter Dettmann, Detlef Schulz   +3 more
openaire   +1 more source

An Improved Voltage-Type Grid-Connected Control Strategy for Compensating Unbalanced Voltage

2018 International Power Electronics Conference (IPEC-Niigata 2018 -ECCE Asia), 2018
During grid faults, the grid-connected inverter (GCI) cannot work well by only using the traditional droop control. Besides, the unbalance factor of voltage/current at Common Coupling Point (PCC) may increase significantly. Therefore, in order to ensure GCI stable operation during grid fault, the GCI should integrate the ability to compensate for the ...
Liu Hongpeng, Zhou Jiajie, Wang Wei
openaire   +1 more source

Transient operation of grid-connected voltage source converter under unbalanced voltage conditions

Conference Record of the 2001 IEEE Industry Applications Conference. 36th IAS Annual Meeting (Cat. No.01CH37248), 2002
In this paper, the operation of shunt-connected voltage source converters under unbalanced voltage conditions is investigated. The attention focuses on voltage dips, thus on transient operation. The importance of using a fast and accurate method for detection of sequence components of the grid voltage affected by a fault is emphasized.
G. Saccomando, J. Svensson
openaire   +1 more source

The Simulation Studies of PWM Voltage Source Rectifier under Unbalanced Grid Voltage

Applied Mechanics and Materials, 2014
Under the balanced or unbalanced grid voltage, the PWM voltage source rectifiers should have many advantages such as sinusoidal input current, unity power factor, four-quadrant operation, the DC voltage stability, etc., so it can be employed in very broad application field.
Jun Li Zhang, Yu Ren Li
openaire   +1 more source

Modeling and control of a grid-connected BDFM under unbalanced grid voltage conditions

2011 IEEE International Electric Machines & Drives Conference (IEMDC), 2011
info:eu-repo/semantics ...
Sotoodeh, Pedram, Seyedmahdi, Izadkhast, Khosravi, Hamed, Oraee, Hashem   +3 more
openaire   +2 more sources

An improved voltage support strategy of grid-connected inverter under unbalanced grid condition

2017 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific), 2017
In order to ensure three-phase grid-connected inverter output voltage symmetry under unbalanced grid voltage, an improved control strategy is proposed in this paper. The proposed control strategy includes power, voltage and current three loops. The complex coefficient-filter (CCF) is used to obtain the positive and negative sequence of unbalance output
Wang Wei, Li Pengfei, Li Fen, Liu Guihua
openaire   +1 more source

A control method of PV grid-connected inverter under grid voltage unbalanced drops

2018 Chinese Control And Decision Conference (CCDC), 2018
To satisfy the requirements of low voltage ride-through (LVRT) capability of PV grid-connected inverter under certain circumstances that three-phase grid voltage shows asymmetrical drops, an unbalance control strategy of the grid-connected inverter is designed in this paper.
Liqun Shang, Weiwei Zhu, Zhuojun Li
openaire   +1 more source

The control for grid connected inverter of distributed generation under unbalanced grid voltage

2009 International Conference on Sustainable Power Generation and Supply, 2009
This paper describes a new control scheme of grid connected inverter of DG (distributed generation) under unbalanced grid voltage. In this paper, the proposed scheme of synchronous reference frame (SRF) controller can reduce the influence of unbalanced grid voltage, which is mainly caused by unbalanced distribution of single-phase and non-linear loads,
null Zhang Guowei, null Wei Tongzhen, null Huang Shengli, null Kong Lingzhi   +3 more
openaire   +1 more source

Improved Grid Synchronization Control of Doubly Fed Induction Generator Under Unbalanced Grid Voltage

IEEE Transactions on Energy Conversion, 2011
An improved grid synchronization control scheme of the wind energy conversion system based on the doubly fed induction generator (DFIG) under unbalanced grid voltage is proposed in this paper. In both the positive and negative sequence models, respectively, the degrees of relevancy among rotor voltages, rotor currents, and stator voltages are ...
Si Zhe Chen, Norbert C. Cheung, Yun Zhang, Miao Zhang, Xiong Min Tang   +4 more
openaire   +1 more source

Advanced Control of Grid-Connected Current Source Converter Under Unbalanced Grid Voltage Conditions

IEEE Transactions on Industrial Electronics, 2018
There are technical challenges when the grid-connected current source converter operates under unbalanced grid voltage conditions. The negative sequence component of the unbalanced grid voltage would result in the low-frequency ripple at dc side, as well as current harmonics at ac side. It has an adverse impact on the system operation.
Xiaoqiang Guo, Yong Yang, Xue Zhang
openaire   +1 more source