Instantaneous harmonic decomposition technique for three‐phase current based on multiple reference coordinates

Abstract

Current harmonic decomposition is important to power systems. Current signal is classified into stationary and nonstationary signal according to whether the parameters change with time. This study focuses on the instantaneous harmonic decomposition of three-phase permanent magnet synchronous motor currents in non-stationary process. First, based on the definition of the instantaneous frequency in non-stationary process, the concept of the spatial frequency based on the electrical angle is proposed. Under this definition, the spatial frequency no longer varies with the rotational speed. A new instantaneous harmonic decomposition method based on multiple reference coordinates is then proposed. To verify the effectiveness of the new method, it is used to analyse constructed currents and experimental currents. Finally, the new method is compared with other analysis methods and proved to be the most accurate and effective.

Interior permanent magnet synchronous motor minimum current harmonics torque ripple suppression strategy based on magnetic co‐energy model

“…7 a . The harmonics decomposition method adopts the algorithm proposed in reference [28, 29] and the harmonics controller in reference [19]. The harmonic controller is shown in Fig.…”

Improved Deadbeat Predictive Control Based Current Harmonic Suppression Strategy for IPMSM

“…In terms of current harmonic extraction, the multiple synchronous rotating frame transformation (MSRFT) method has received extensive attention in recent years [3][4][5][6][7]. This method transforms the stator current into a combination of DC quantities (current harmonics of specified frequency) and several AC quantities, and the first-order low-pass filter (FLPF) is used to extract the current harmonics.…”

Multiple Synchronous Rotating Frame Transformation-Based 12th Current Harmonic Suppression Method for an IPMSM

“…In recent years, some scholars have proposed a current harmonic suppression strategy based on multiple synchronous rotating frame transformations (MSRFTs), which consists of two parts: the current harmonic extraction and voltage harmonic generation. For the current harmonic extraction part, some scholars convert the three-phase current from an AC component to a DC component through the same coordinate transformation process as the current harmonic frequency, and combine the low-pass filter (LPF) to extract the current harmonic component [11,12]. However, for the high-current motors used in electric vehicles, the amplitude of the fundamental current is much larger than the harmonic content.…”