Analysis and implementation of passive soft switching snubber for PWM inverters

Enhui Chu,Zhiyong Wang,Yunjing Kang 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.1

To realize a three-phase soft-switching inverter with a simple structure, low cost, and easy modularization, this paper proposes a novel three-phase passive soft-switching inverter, which realizes soft-switching of the switches in the inverter through energy consumption of the auxiliary snubber circuit. When compared with the traditional passive soft-switching inverter, it avoids the use of transformers, coupled inductors, and bulk electrolyte capacitors. Thus, it has a small size, a high power density, and is suitable for integration. Its three single phases are independent of each other, which makes it easy for the inverter to apply various control strategies. This study chooses a single-phase circuit, and investigates the operating principle, soft-switching implementation characteristics, and parameter design methods of the novel passive soft-switching inverter under various operation modes. Finally, a 10 kW/16 kHz prototype is made using an IGBT as a switch, and experiments are conducted to confirm the validity of the inverter.

A Novel Single-Phase Soft-Switching Unipolar PWM Inverter

Maoh-Chin Jiang,Wei-Shiang Wang,Huang-Kai Fu,Kuei Wu-Chang 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

A novel single-phase soft-switching unipolar PWM inverter (SSUPI) using a simple auxiliary resonant unit is proposed. All main switches of high-frequency arm operate at zero-voltage-switching (ZVS) turn-on, while the auxiliary switches operate at zero-current-switching (ZCS) turn-off. All main switches of low-frequency arm operate at 60 ㎐ to greatly reduce switching losses. As a result, commutations of the main power devices occur with low losses. Consequently, higher efficiency is achieved. Moreover, a unipolar PWM scheme is used to reduce the output voltage harmonics. Some experimental results of the proposed SSUPI, rated 500 W and operated at 40 ㎑, are presented for demonstration.

A Ringing Surge Clamper Type Active Auxiliary Edge-Resonant DC Link Snubber-Assisted Three-Phase Soft-Switching Inverter using IGBT-IPM for AC Servo Driver

Yoshitsugu, Junji,Yoshida, Masanobu,Hiraki, Eiji,Inoue, Kenji,Ahmed, Tarek,Nakaoka, Mutsuo The Korean Institute of Electrical Engineers 2002 KIEE International Transactions on Electrical Mach Vol.b2 No.3

This paper presents an active auxiliary edge-resonant DC link snubber with a ringing surge damper and a three-phase voltage source type zero voltage soft-switching inverter with the resonat snubber treated here for the AC servo motor driver applications. The operation of the active auxiliary edge-resonant DC link snubber circuit with PWM voltage is described, together with the practical design method to select its circuit parameters. The three-phase voltage source type soft-switching inverter with a single edge-resonant DC link snubber treated here is evaluated and discussed for the small-scale permanent magnet (PM) type-AC servo motor driver from an experimental point of view. In addition to these, the AC motor stator current and its motor speed response for the proposed three-phase soft-switching inverter employing Intelligent Power Module(IPM) based on IGBTS are compared with those of the conventional three-phase hard-switching inverter using IPM. The practical effectiveness of the three-phase soft-switching inverter-fed permanent magnet type AC motor speed tracking servo driver is proven on the basis of the common mode current in a novel type three-phase soft-switching inverter-fed AC motor side and the conductive noise on the mains terminal interface voltage as compared with those of the conventional three-phase hard-switching inverter-fed permanent magnet type AC servo motor driver for the speed tracking applications.

Soft Switching Three Phase Inverter with Two Auxiliary Switches

Mohammad Mahdavi,Mohammad Reza Amini,Amin Emrani,Hosein Farzanehfard 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

In this paper, a new three phase soft switching inverter is presented. All of the semiconductor elements of this converter are soft switched. Employing only two auxiliary switches as DC-link switches and a simple control circuit are the advantages of the proposed inverter. The analytical equations and operating modes of the presented inverter are explained in details. The design considerations are presented and the experimental results verify the theoretical analysis.

Soft-Switching T-Type Multilevel Inverter

Tianyu Chen,Mehdi Narimani 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

In order to improve the conversion efficiency and mitigate the EMI problem of conventional hard-switching inverters, a new soft-switching DC-AC inverter with a compact structure and a low modulation complexity is proposed in this paper. In the proposed structure, resonant inductors are connected in series for the arm branches, and resonant capacitors are connected in parallel for the neutral point branches. With the help of resonant components, the proposed structure achieves zero-current switching on the arm branches and zero-voltage switching on the neutral point branches. When compared with state-of-art soft-switching topologies, the proposed topology does not need auxiliary switches. Moreover, the commutation algorithm to realize soft-switching can be easily implemented. In this paper, the principle of the resonant operation of the proposed soft-switching converter is presented and its performance is verified through simulation studies. The feasibility of the proposed inverter is evaluated experimentally with a 2.4-kW prototype.

Auxiliary resonant commutated pole soft‑switching inverter with simple topology

Enhui Chu,Tianyu Zhang,Zhiyong Wang 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.2

To address the complex topology of auxiliary resonant commutated pole inverters and the large current stress of auxiliary switches, this paper proposes an auxiliary resonant commutated pole soft-switching inverter with a simple topology. The proposed inverter not only reduces the current stress of the auxiliary switches and the loss caused by the reactive energy conversion in the circuit but also simplifies the topology of the auxiliary commutated circuit, reduces the cost of the inverter, and improves the reliability of the inverter. The inverter is suitable for small and medium power applications. Under the proposed modulation strategy, the operation principle of the inverter, the conditions of soft-switching realization, and the optimal parameter design method are analyzed in detail according to the equivalent circuit diagrams in different operating modes. Finally, a 10-kW, 16-kHz prototype is fabricated using insulated gate bipolar transistors (IGBT) as switches, and the effectiveness of this inverter is verified through experiments.

Soft-switching buck inverter

Xu, Wei,Wu, Xiaohua,Hong, Feng The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.1

The soft-switching buck inverter, which is mainly applied to solve the contradictions between the switching frequency and the shoot-through problem along with the dead-time effect, is proposed in this paper. A detailed analysis of the relationship between the range of the duty ratio to realize soft-switching as well as the additional voltage stress and the current stress is conducted. In addition, a 1 kW prototype is designed and established. Results of simulations and experiments verify the validity of the theoretical analysis. Furthermore, the proposed soft-switching buck inverter has a strong practical significance in situations where medium and high power outputs are required.

Soft Switching Three Phase Inverter with Two Auxiliary Switches

Mahdavi, Mohammad,Amini, Mohammad Reza,Emrani, Amin,Farzanehfa, Hosein The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

In this paper, a new three phase soft switching inverter is presented. All of the semiconductor elements of this converter are soft switched. Employing only two auxiliary switches as DC-link switches and a simple control circuit are the advantages of the proposed inverter. The analytical equations and operating modes of the presented inverter are explained in details. The design considerations are presented and the experimental results verify the theoretical analysis.

Efficient single-phase full-bridge soft-switching inverter

Wang, Qiang,Wang, Youzheng The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.4

A MOSFET is often applied as the switch in medium and small power single-phase full-bridge inverters. In order to achieve efficient operation at a high switching frequency, a new efficient inverter is presented in this paper. In addition, two sets of identical auxiliary units are arranged on the two bridge arms. When the main switches need to be turned on in each switching period, the voltage across the resonant capacitor can become zero. Thus, the main switching device can achieve zero-voltage turn-on, which can eliminate the capacitive turn-on loss existing in the MOSFET and help with the efficient operation of the inverter. The working process of the auxiliary unit and the design rules of the parameters are analyzed. Experimental results indicate that the main switching device can work in the state of zero-voltage soft-switching, and that the rated efficiency in the inverter is equal to 98.9%. This is more than that of similar inverters. This topology is significant for studies on efficient single-phase full-bridge inverters with medium and small power.

Soft-Switching T-Type Multilevel Inverter

Chen, Tianyu,Narimani, Mehdi The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

In order to improve the conversion efficiency and mitigate the EMI problem of conventional hard-switching inverters, a new soft-switching DC-AC inverter with a compact structure and a low modulation complexity is proposed in this paper. In the proposed structure, resonant inductors are connected in series for the arm branches, and resonant capacitors are connected in parallel for the neutral point branches. With the help of resonant components, the proposed structure achieves zero-current switching on the arm branches and zero-voltage switching on the neutral point branches. When compared with state-of-art soft-switching topologies, the proposed topology does not need auxiliary switches. Moreover, the commutation algorithm to realize soft-switching can be easily implemented. In this paper, the principle of the resonant operation of the proposed soft-switching converter is presented and its performance is verified through simulation studies. The feasibility of the proposed inverter is evaluated experimentally with a 2.4-kW prototype.