Dynamic Phasor Modeling of Various Multipulse Rectifiers and a VSI Fed by 18-Pulse Asymmetrical Autotransformer Rectifier Unit for Fast Transient Analysis

Abstract

To study the fast modelling of dynamic characteristics caused by power electronic switching, the dynamic phasor (DP) theory based on the time-varying Fourier decomposition and frequency shifting is firstly applied to the modelling of various multipulse rectifiers. The DP model for symmetrical 12-pulse phase-shifting reactor rectifier unit (PSR-RU) is derived with model order reduction, relations between ac and dc terminals, and Taylor series expansion. The DP model of asymmetrical 18-pulse autotransformer rectifier unit (AT-RU) is proposed based on the switching functions expressed in the DP domain. Meanwhile, the DP model of voltage source inverter (VSI) fed by asymmetrical 18-pulse AT-RU is built with the harmonic state-space (HSS) equations. Under both balanced and unbalanced conditions, the good calculation accuracy and rapid simulation speed of the developed DP models are validated by the detailed time-domain (TD) simulation.

Hybrid Dynamic Phasor Modeling Approaches for Accurate Closed-Loop Simulation of Power Converters

“…From Fig. 3, it can be inferred that the dependency of the bessel function on the switching harmonic m is significant than the grid harmonic n. In this paper, we Applying (5) with ω k = mω s +nω 0 and the corresponding time period as T mn = 2π ω k to (10) results in the DP phasor switched model of the single phase inverter given by (12). The switched voltage waveform v inv obtained by post processing the DPs corresponding to m = 6 and n = 5 is shown in Fig.…”

“…The dynamic phasor concept was initially referred to as Generalized State Space Averaging (GSSA) which was first introduced in [4] where it was applied for a variety of switched circuits. The DP modelling method applied to DC/DC converters [5]- [7] and DC/AC converters such as three phase inverters [8]- [13], MMCs [14] and other power electronics such as Auto Transformer Rectifier Unit (ATRU) [12] do not propose strategies to reduce model complexity and do not provide recommendations of a selection criteria for harmonics. Furthermore, the methods used to represent the controller and the domain used to simulate the controller is not described.…”

Project and Performance Evaluation on an Optimized 18-Pulse Rectifier With Delta-Differential Connection ATRU and Cascaded Boost Converters for More Electric Aircraft

“…Finally, from the equations of currents in the time domain given by (26), the RMS value of the currents drawn from the grid are obtained by (27).…”

Power Quality Analysis of the Output Voltage of AC Voltage and Frequency Controllers Realized with Various Voltage Control Techniques

“…The power converting topologies realized with slim type DC link capacitors have improved harmonics suppression capabilities once they are connected in parallel with other power converters. In the AC to DC conversion process, the higher pulse rectifier's topologies may also be employed but their use is restricted to some applications due to their complex circuit arrangement [13][14][15][16]. The mathematical computation of output voltage and input current harmonics of a six-pulse rectifier is reported in [17] but they are not practically validated.…”