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Multipulse Converter
Published in Vinod Kumar, Ranjan Kumar Behera, Dheeraj Joshi, Ramesh Bansal, Power Electronics, Drives, and Advanced Applications, 2020
Vinod Kumar, Ranjan Kumar Behera, Dheeraj Joshi, Ramesh Bansal
To protect the devices from the switching stresses of high off-state voltages and high on-state current, snubber circuits are used. Snubber circuits are of two types: turn-off snubber and turn-on snubber. The turn-off snubber uses a resistor, capacitor, and diode. During turn off, capacitor C effectively comes across the device and limits the rate of rising of voltage. Thus, overvoltages during the turn-off process are snubbed. The device turn-off loss is also reduced. When properly sized, the snubber may also marginally reduce the overall losses. Figure 11.31 shows the diode-clamped inductive load with turn-off snubber. The switching trajectory with the snubber circuit is shown in Figure 11.32.
Inverters
Published in Timothy L. Skvarenina, The Power Electronics Handbook, 2018
Michael Giesselmann, Attila Karpati, István Nagy, Dariusz Czarkowski, Michael E. Ropp, Eric Walters, Oleg Wasynczuk
increase power density, and improve performance. There are two basic methods for eliminating switching loss. The first is through the use of snubbers. A snubber is a circuit designed to modify the waveform of the voltage across or the current through the switch [1]. Turn-on snubbers limit the rise of the current during switch turn-on, and turn-off snubbers reduce the voltages experienced by the switch during turn-off. Snubbers can be effective in reducing switch power dissipation and allowing higher switch frequencies, but most snubber configurations dissipate power themselves, and thus the efficiency of the inverter can still suffer as the switching frequency increases [1]. Snubbers can also be quite complex and add many additional parts to the inverter.
DC/AC Inverters
Published in Ali Emadi, Handbook of Automotive Power Electronics and Motor Drives, 2017
In hard switching, the switching locus moves through the active region of the volt-ampere area, which stresses the device. The reliability of the device may be impaired due to prolonged hard switching operation. A snubber circuit reduces power loss in the device during switching and protects the device from switching stress of high voltage and currents.
A Novel Buck Converter Based Three-Phase Inverter with Feedforward Supported Closed-Loop Control
Published in Electric Power Components and Systems, 2020
As seen from Figure 5, the designed snubber circuits are two kinds as: serial polarized RLD snubber circuit and parallel polarized RCD snubber circuit. The RLD snubber circuits that are serial connected to the IGBTs provide nearly zero current switching during turn on processes of the IGBTs. The RCD snubber circuits that are parallelly connected to the IGBTs provide nearly zero voltage switching during the turn off process of the IGBTs. So, switching losses of the IGBTs are transferred to the snubber circuits. On the other hand, overvoltage problems are prevented during turn off processes. Thus, the IGBTs are protected from abnormal conditions to obtain robust inverter operation. By the way, it must be noted that the snubber circuits just take the switching losses on them from the IGBTs, but they cannot prevent occurring of the losses in the inverter circuit. But they prevent occurring of overheating on the IGBTs caused by the mentioned switching losses.
Enhancement of self-lift SEPIC converter performance based on different inductor types
Published in Australian Journal of Electrical and Electronics Engineering, 2020
A snubber circuit is applied and tested in order to reduce ringing and voltage spikes at the switch node, which generated due to circuit parasitic inductance. A snubber circuit is an energy-absorbing circuit, consisting of a resistor (RSNUB) and a capacitor (CSNUB) from the switch node to the ground. In this concern, the following steps were carried out for determination of the R-C snubber circuit values (Falin. 2006; Gaurav and Ray, 2017): Add capacitance value (CADD) from the switch node to the ground to reduce Fr by half.Calculate Cpar which is the minimum value of CSNUB and Lpar where:
Improved quadratic boost converter using switching coupled-inductor and voltage-doubler
Published in Australian Journal of Electrical and Electronics Engineering, 2019
Yiyang Li, Swamidoss Sathiakumar, John Long Soon
In order to make this technique fully useable, a snubber circuit is required to block the high voltage overshoot across inductors and diodes. The leakage inductance of the coupled-inductor will cause a decline in the performance of the circuit. The snubber can absorb the energy of leakage inductance and eliminate the switching voltage spikes. In Figure 2, a snubber is put in the output side, across the secondary part of the coupled-inductor. This design can maintain the voltage gain with the topology in Figure 1 and reduce the switching spike during operations. While, such kind of snubber may decrease the efficiency of the circuit since during its operations, the snubber will absorb the active power (Wu et al. 2008; Wai and Duan 2005). To keep the efficiency and decrease the negative effects of the auxiliary circuit, some improvements are proposed in the circuit.