DC link voltage balancing control of a three-phase cascade power regulation system with star connection

Since a T-type three-level PWM converter has several intrinsic advantages, it has been researched for various applications such as grid-connected converter systems. However, it necessarily requires an additional voltage control loop for balancing the upper and the lower DC-link voltage. To satisfy this requirement, an offset voltage is widely used to provide a neutral point current without affecting other variables such as total DC-link voltage and three-phase input current. However, these methods are mostly based on the averaged value between the applied offset voltage and the neutral point voltage or current, and there is no exact analytical model. Therefore, in this paper, the exact theoretical relationship between the offset voltage and the neutral point current is analyzed. This result can be expected to be useful for an effective voltage balancing control loop design as well as the better understanding of the whole system operation. The validity of the obtained analytical model is verified by simulation and experimental results.

Download Full-text

Development of Wind IPMSG Based Bipolar DC Microgrids

Journal of Energy and Power Technology ◽

10.21926/jept.2102028 ◽

2021 ◽

Vol 03 (02) ◽

pp. 1-1

Author(s):

Xiang-Yu Sun ◽

◽

Ping-Hong Jhou ◽

Min-Ze Lu ◽

Chang-Ming Liaw ◽

...

Keyword(s):

Synchronous Generator ◽

Voltage Balancing ◽

Dc Microgrids ◽

Three Phase ◽

Switch Mode ◽

Interior Permanent Magnet ◽

Dc Bus ◽

Bus Voltage ◽

Balancing Control ◽

Power Component

This paper presents the development of a wind Interior Permanent-Magnet Synchronous Generator (IPMSG) based bipolar DC microgrids along with various switch-mode rectifiers. Firstly, the wind IPMSG is established and adequately controlled to possess satisfactory generating characteristics during different driven speeds and loads. Later, the boost switch-mode rectifier (SMR) based bipolar DC bus is established. Further, three-phase single-switch (3P1SW) boost SMR, three-phase two-switch (3P2SW) three-level boost SMR, and a three-phase three-switch (3P3SW) Vienna SMR are comparatively evaluated. Along with the proposed robust voltage and current controls, a well-regulated microgrid DC-bus voltage is established. Moreover, the voltage balancing control is proposed to minimize the imbalance in the bipolar DC-bus voltage. For the wind IPMSG having Vienna SMR, the commutation angle setting is adjusted to use the reluctance power component effectively.

Download Full-text

Three-Phase Y-Rectifier Cyclic 2 Out of 3 DC Output Voltage Balancing Control Method

IEEE Transactions on Power Electronics ◽

10.1109/tpel.2008.2009173 ◽

2009 ◽

Vol 24 (1) ◽

pp. 34-44 ◽

Cited By ~ 11

Author(s):

Juergen Biela ◽

Uwe Drofenik ◽

Franz Krenn ◽

Johann Miniboeck ◽

Johann W. Kolar

Keyword(s):

Output Voltage ◽

Control Method ◽

Voltage Balancing ◽

Three Phase ◽

Balancing Control

Download Full-text

Modulator for 4-level Flying Capacitor Converter with Balancing Control in the Closed Loop

Transactions on Electrical Engineering ◽

10.14311/tee.2016.3.066 ◽

2020 ◽

Vol 5 (3) ◽

pp. 66-69 ◽

Cited By ~ 2

Author(s):

Jiří Brychcín ◽

Dušan Janík ◽

Tomáš Košan ◽

Zdeněk Peroutka

Keyword(s):

Electric Motor ◽

Closed Loop ◽

Motor Drive ◽

Voltage Balancing ◽

Three Phase ◽

Electric Motor Drive ◽

Balancing Control

This paper presents a modulator with an active voltage balancing control for the three-phase four-level FLC converter based electric motor drive for applications supplied directly from a 6 kV ac-grid. It describes a modulation algorithm of the FLC converter by using the phase shifted PWM modulation with balancing voltage of the flying capacitor by using P controllers in the closed loop. The proposed control was verified by experiments carried out on the down-scale drive prototype of the rated power of 35 kVA.

Download Full-text