Precise Correction of Current Zero-Crossing Distortion of Totem Pole PFC Converter

Author(s):  
Jinshui Zhang ◽  
Yan Zhang ◽  
Shah Zaman ◽  
Rui Cao ◽  
Xiaoyang Gao ◽  
...  
Keyword(s):  
2012 ◽  
Vol 562-564 ◽  
pp. 1531-1536
Author(s):  
Ming Xing Zhu ◽  
Jing Bo Shi

In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control strategy can eliminate the problems of the dead time effects. But the traditional non-dead-time control strategy heavily depends on the current zero-crossing detection, which may cause the output voltage distortion or even a short circuit. Based on the analysis of the reason for the distortion, a new optimized non-dead-time control method is proposed. Two methods for the detection of the overlapping area are enumerated. The conclusions are confirmed by the simulation results with MATLAB/ SIMULINK.


2017 ◽  
Vol 45 (12) ◽  
pp. 1329-1338 ◽  
Author(s):  
Kuo-Ing Hwu ◽  
Wen-Zhuang Jiang

2014 ◽  
Vol 532 ◽  
pp. 62-69
Author(s):  
Yi Chuan Gao ◽  
Guo Chang Liu

A novel actuator controller for greenhouse control system is proposed in this paper. This controller can solve the problems existing in traditional greenhouse control system such as generating electric arc, short circuit risk, lack of communication and smart ability. We adopt five separate magnetic latching relays to control the three-phase motor. In order to prevent generating electric arc in the process of turning off relay, the alternating current zero-crossing detection circuit is designed. In software side, the relay-off task program is running in the real-time operating system, which can ensure turn-off operation at the point of alternating current zero-crossing. In addition, the controller is capable of detecting motors operation parameter and having multiple communication interfaces. Finally, we implement our controller in practice and experimental results meet the design requirements.


Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3335 ◽  
Author(s):  
Wenbin Jia ◽  
Wenxia Sima ◽  
Tao Yuan ◽  
Ming Yang ◽  
Potao Sun

The multi-chamber arc-extinguishing structure (MAS), which consists of a lot of semi-closed short-gap arc-extinguishing chambers (SSAC) in series, can be used in parallel gap lightning protection devices to improve the ability to extinguish power frequency follow current. The arc-extinguishing ability of single SSAC directly affects the arc-extinguishing performance of the whole MAS. Therefore, the arc-extinguishing performance of MAS can be improved by optimizing single SSACs. A two-dimensional model of the arc plasma in a SSAC is built based on the magneto-hydrodynamic (MHD) theory. The motion characteristics of an arc in the SSAC are simulated and analyzed. An optimization method of the SSAC structure is proposed. Finally, an impact test platform is built to verify the effectiveness of the optimized SSAC structure. Results show that the short-gap arc forms a high-speed airflow in the SSAC and the arc plasma sprays rapidly to the outlet until the arc is extinguished at its current zero-crossing point. The amplitude of airflow velocity in the optimized structure can be increased to about 8-fold the velocity in the basic structure. Experiments also show that the dissipation time of an arc in the optimized SSAC is 79.2 μs, which is much less than that in the original structure (422.4 μs).


2014 ◽  
Vol 571-572 ◽  
pp. 906-909
Author(s):  
Zhu Lei Shao

In order to reduce the power consumption of the synchronous rectification model buck converter, a current zero crossing detection circuit is designed in this paper. The detection circuit determines the freewheeling current of the synchronous rectification power switch is zero or not by detecting the drain voltage of synchronous rectification power switch. Due to use transistors instead of resistors in the voltage conversion, the accuracy of the detection circuit is less affected by temperature and process corner. From the experimental results, the detection circuit can make accurate current zero crossing detection in different temperatures and process corners, and the detection circuit has strong robustness.


2019 ◽  
Vol 6 (1) ◽  
pp. 73-77
Author(s):  
S. Jugelt ◽  
C. Leu

The increasing usage of medium-voltage direct-current in upcoming electrical energy grid topologies requests novel solutions for MVDC switching. The interruption of direct-currents is accomplished by enforcing a current zero crossing by adequate means and preventing reignition due to the recovering dc voltage. This paper evaluates the rapid separation of the contact elements in mineral oil leading to a liquid flow around the contact elements and the switching arc. The energy turnover of dielectric liquids interacting with an electric arc is considerably higher leading to heavily increased arc voltages compared to dielectric gases. This paper confirms results of earlier publications and carries them further towards a possible usage in an MVDC switching or protection device. Thus a contact arrangement surrounded by mineral oil in combination with an ultra fast electro-magnetic actuator is introduced and performed measurements are discussed.


Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6388
Author(s):  
Woo-Young Lee ◽  
Jang-Un Jun ◽  
Ho-Seok Oh ◽  
Jun-Kyu Park ◽  
Yeon-Ho Oh ◽  
...  

In the study, an interrupting performance test on the 145 kV gas circuit breaker is performed according to three different gases: SF6, g3 (5% NovecTM4710 with 95% CO2), and CO2(70%)/O2(30%) gases. Thanks to research advancements, it is confirmed that CO2 and g3 (5% NovecTM 4710) gases, respectively, have 40% and 75% dielectric strength, compared to that of SF6 gas. The filling pressure and transient recovery voltage criteria of each gas were determined differently in order to compare the maximum interrupting performance of each gas. The pressure of SF6 gas was determined to be 5.5 bar, which is typically used in circuit breakers. The pressure of the other two gases was determined to be 8.0 bar (the maximum available pressure of the test circuit breaker) to find the maximum interrupting performance. Moreover, the rate-of-rise of transient recovery voltage of SF6 was determined as 10 kV/μs, which is the value at the state of maximum interrupting performance of the test circuit breaker with SF6. On the other hand, the rate-of-rise of transient recovery voltages of g3 (5% NovecTM4710 with 95% CO2) and CO2(70%)/O2(30%) gases were, respectively, determined as 4∼5 kV/μs to find the interruption available point. The characteristics of arc conductance, arc current, and arc voltage near the current zero, and post-arc current are analyzed to compare the interrupting performance, according to different arc-quenching gases. The arc current is measured using a current transformer (Rogowski coil), and a signal processing method of the arc current and arc voltage is introduced to increase the reliability of the interrupting performance results. As a result of the test, it is confirmed that the critical arc conductance for all test conditions converged within a certain range and the value is around 0.7 mS. In addition, the critical current slope just before the current zero-crossing during the interrupting process is shown to be 1.8 A/μs between interruption success and failure. Consequently, it is verified that the CO2(70%)/O2(30%) mixture and g3 (5% NovecTM4710 with 95% CO2) have a similar arc extinguishing performance and SF6 has a relatively higher extinguishing performance than that of CO2(70%)/O2(30%) mixture and g3 (5% NovecTM4710 with 95% CO2) under the aforementioned filling pressure and TRV conditions.


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