Capacitors Voltage Switching Ripple in Three-Phase ...
Neutral-point-clamped multilevel converters are currently a suitable solution for a wide range of applications. It is well known that the capacitor voltage balance is a major issue for this topology. In this paper, a brief summary of the basic topologies, modulations, and features of neutral-point-clamped multilevel converters is presented, …
semiconductor switches, controlling voltage balancing across capacitors with proper selection of switching stat es and the classical DC offset injection for controlling neutral point voltage. Architecture of 3-level ANPC MIL inverter is as shown in Figure-I ...
Under complete modulation conditions, this method can control the balance of the neutral-point voltage of DC-link capacitors by adjusting the duty cycle of small …
20b is the capacitors voltage deviation (U C 1 −U C 2) with the proposed simplified algorithm of neutral-point method, and it can be seen that the voltage deviation of three-time fundamental frequency …
In this paper, a simplified control technique is proposed to control capacitor voltages of three-phase Neutral-Point Clamped bi-directional rectifier based on the modified modulation index technique. The modified modulation index technique generates new position of the reference vector in the space vector hexagon keeping both capacitor …
Taking the neutral point N on the DC side as the voltage reference point, the current flowing into the point N is defined as i N; the currents flowing through C 1 and …
This paper addresses the problems associated with the dc-link capacitor voltages of the three-level neutral-point-clamped power converter: the imbalance of the capacitor voltages as well as the presence of an ac-voltage low-frequency oscillation in the dc link of the converter. ...
of capacitor neutral-point voltage are dif ferent between single-phase three-level inverters and TPTL TIs. Henc e, the analysis and control strategy for single-phase three ...
A virtual space vector PWM with active neutral point voltage control and common mode voltage suppression for three-level NPC converters. IEEE Trans. Ind. Electron. 68 (12), 11761–11771 (2021).
Analysis of the Neutral-Point Voltage Self-Balance Mechanism in the Three-Level Full-Bridge DC−DC Converter by Introduction of Flying Capacitors. Abstract: The three-level …
A New Neutral-point Voltage Balance Control Based on ...
This paper proposes the lifetime extension of DC-link capacitors in three-level inverters based on the neutral-point (NP) current. High-capacity inverters require large-size capacitors to maintain robust DC-link voltage. The proposed method suppresses the ripple current of the DC-link capacitors by replacing the switching states, which are …
DC-link capacitor loss with fault-tolerance control in three-level hybrid active neutral point clamped (ANPC) inverters was analyzed in this paper. The three-level hybrid ANPC inverter consisted of 18 switch devices such as silicon insulated-gate bipolar transistors and silicon carbide metal-oxide-semiconductor field effect transistors. The …
According to the above analysis, when k M1 = 1/3, the virtual medium vector has no effect on the dc-link capacitor voltage.When k M1 = 1/6 and k M1 = 1/2, the influence of the virtual medium vector on the dc-link capacitor voltage are opposite.Therefore, the value of k M1 can be dynamically adjusted according to the …
The modulation strategy LMZVM (large, middle, and zero vector modulation) can be widely adopted in the three-level 7 photovoltaic (PV) inverter, because it reduces the ground current and produces little neutral-point (NP) voltage in normal operation. However, in low-voltage ride-through (LVRT) operation, the NP voltage …
Neutral-point voltage unbalancing is a common problem in three-level inverters. The original neutral-point voltage balancing circuit is the buck–boost converter. Since the inductor carries low frequency components, the power density is limited. At the same time, the efficiency is low because the soft switching cannot be realized. In this …
This paper provides a comprehensive analysis of the capacitors voltage switching ripple for three-phase three-level neutral point clamped (NPC) inverter topologies. The voltage ripple amplitudes of the two dc-link capacitors are theoretically estimated as a function of both amplitude and phase angle of output current and the inverter modulation index. In …
In the research field of multilevel converters, three-level NPC (neutral-point-clamped) converters, which unfortunately may cause the deviation of the neutral-point voltage of DC-link capacitors, are widely discussed. Theoretically, virtual space vector modulation (VSVM) could guarantee the balance control of the neutral-point voltage. …
The sizing of the DC-link capacitor in a three-level inverter is based on the RMS current flowing through it. This paper analyses the DC-link capacitor RMS current in a neutral-point clamped (NPC) inverter and expresses the same as a function of modulation index, line-side current amplitude and power factor. Analytical closed-form expressions …
This paper analyses the DC-link capacitor RMS current in a neutral-point clamped (NPC) inverter and expresses the same as a function of modulation index, line …
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