Reduction of high‐frequency injection losses, acoustic noise and total harmonic distortion in IPMSM sensorless drives

Abstract

In saliency-based sensorless methods, the amplitude of the injected voltage cannot be reduced to levels below its specified value because of the reasonable signal required for the noise ratio. Increasing the injection signal amplitude increases not only the acoustic noise and high-frequency (HF) losses, but also the total harmonic distortion (THD) of the output voltage and current ripples. A new pulsating semi-impulse signal injection method based on the current sensing technique is proposed for the sensorless control of interior permanent magnet synchronous motors (IPMSMs). The proposed method aims to control the motor speed and reduce some problems due to the HF signal injection involving acoustic noise, HF losses and THD of the output voltage. Taking into account the premium injection angle, these problems are reduced significantly as compared to those in conventional square-wave methods. Hence, the proposed method increases the sensorless driver efficiency and its application scope. The effectiveness of the proposed method is then confirmed with computer simulation and experimental tests. Experimental comparisons at the same injection frequency and injection effective voltage show that the performance of the proposed method is beneficial. All experiments were performed on a IPMSM with V-shaped PMs which is used in a refrigerator compressor.

Active noise control by means of high frequency injection in electric motors

“…An additional limitation of HFI methods is HF losses that in turn result in an increase of the motor's temperature [45,46]. To understand the thermal effects of HFI, it is necessary to first identify the different types of HF losses.…”

An enhanced feedforward flux weakening control for high‐speed permanent magnet machine drive applications

“…[26][27][28][29] have proposed different methods for L q identification using recursive least squares algorithm, model reference adaptive method and extended Kalman filter. These methods depend on the d-axis steady state voltage equation to extract the apparent FIGURE 4 Diagram of proposed L q identification method, where the low-frequency components i df and i qf are used for current control; high-frequency component I qHF is used for L q identification. V q_dis and V d_dis are from Figure 8 and 9 inductance in q-axis.…”

“…In recent years, the interior permanent-magnet synchronous machines (IPMSMs) are widely used in the high-speed drive applications such as electric vehicles [1,2] due to promising features, including high torque-to-ampere ratio, small volume, fast dynamic response, and most importantly, the geometrically buried magnets of IPMSM's rotor which makes it mechanically robust to operate at a high speed [3,4]. IPMSMs with a wide constant power to speed ratio are also considered as a potential candidate for the other high-speed applications such as aircraft starter/generator (SG) [5].…”

Modelling of Earphone Design Using Principal Component Analysis

“…Firstly, it is without any question that the expression of the original sound is one of the critical criteria for a sound system. Therefore, THD is found to be an important metric for evaluating the sound quality of designed earphones [14]. In essence, this factor quantifies the amount of distortion introduced by the earphone to the original signal, highlighting the contrast between the two.…”