Comparative study of low-pass filter and phase-locked loop type speed filters for sensorless control of AC drives

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

High quality speed information is one of the key issues in machine sensorless drives, which often requires proper filtering of the estimated speed. This paper comparatively studies typical low-pass filters (LPF) and phase-locked loop (PLL) type filters with respect to ramp speed reference tracking and steady-state performances, as well as the achievement of adaptive cutoff frequency control. An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed, which is suitable for applying LPF for sensorless drives of AC machines, especially when fixed-point digital signal processor is selected e.g. in mass production. Furthermore, the potential of adopting PLL for speed filtering is explored. It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF. Moreover, it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral (PI) gains, which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance. The proposed filters are verified experimentally. The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended.
Original languageEnglish
JournalCES Transactions on Electrical Machines and Systems
Volume1
Issue number2
Pages (from-to)207-215
Number of pages9
ISSN2096-3564
DOIs
Publication statusPublished - Jul 2017

Fingerprint

Low pass filters
Phase locked loops
Cutoff frequency
Digital signal processors
Sensorless control

Keywords

  • Adaptive cutoff frequency
  • Low-pass filter
  • Machine sensorless drive,
  • Phase-locked loop
  • Speed filter
  • Static error

Cite this

@article{98335d687df6462eabdaf4ad4a3adc17,
title = "Comparative study of low-pass filter and phase-locked loop type speed filters for sensorless control of AC drives",
abstract = "High quality speed information is one of the key issues in machine sensorless drives, which often requires proper filtering of the estimated speed. This paper comparatively studies typical low-pass filters (LPF) and phase-locked loop (PLL) type filters with respect to ramp speed reference tracking and steady-state performances, as well as the achievement of adaptive cutoff frequency control. An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed, which is suitable for applying LPF for sensorless drives of AC machines, especially when fixed-point digital signal processor is selected e.g. in mass production. Furthermore, the potential of adopting PLL for speed filtering is explored. It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF. Moreover, it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral (PI) gains, which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance. The proposed filters are verified experimentally. The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended.",
keywords = "Adaptive cutoff frequency, Low-pass filter, Machine sensorless drive,, Phase-locked loop, Speed filter, Static error",
author = "Dong Wang and Kaiyuan Lu and Rasmussen, {Peter Omand} and Zhenyu Yang",
year = "2017",
month = "7",
doi = "10.23919/TEMS.2017.7961343",
language = "English",
volume = "1",
pages = "207--215",
journal = "CES Transactions on Electrical Machines and Systems",
issn = "2096-3564",
number = "2",

}

TY - JOUR

T1 - Comparative study of low-pass filter and phase-locked loop type speed filters for sensorless control of AC drives

AU - Wang, Dong

AU - Lu, Kaiyuan

AU - Rasmussen, Peter Omand

AU - Yang, Zhenyu

PY - 2017/7

Y1 - 2017/7

N2 - High quality speed information is one of the key issues in machine sensorless drives, which often requires proper filtering of the estimated speed. This paper comparatively studies typical low-pass filters (LPF) and phase-locked loop (PLL) type filters with respect to ramp speed reference tracking and steady-state performances, as well as the achievement of adaptive cutoff frequency control. An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed, which is suitable for applying LPF for sensorless drives of AC machines, especially when fixed-point digital signal processor is selected e.g. in mass production. Furthermore, the potential of adopting PLL for speed filtering is explored. It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF. Moreover, it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral (PI) gains, which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance. The proposed filters are verified experimentally. The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended.

AB - High quality speed information is one of the key issues in machine sensorless drives, which often requires proper filtering of the estimated speed. This paper comparatively studies typical low-pass filters (LPF) and phase-locked loop (PLL) type filters with respect to ramp speed reference tracking and steady-state performances, as well as the achievement of adaptive cutoff frequency control. An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed, which is suitable for applying LPF for sensorless drives of AC machines, especially when fixed-point digital signal processor is selected e.g. in mass production. Furthermore, the potential of adopting PLL for speed filtering is explored. It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF. Moreover, it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral (PI) gains, which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance. The proposed filters are verified experimentally. The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended.

KW - Adaptive cutoff frequency

KW - Low-pass filter

KW - Machine sensorless drive,

KW - Phase-locked loop

KW - Speed filter

KW - Static error

U2 - 10.23919/TEMS.2017.7961343

DO - 10.23919/TEMS.2017.7961343

M3 - Journal article

VL - 1

SP - 207

EP - 215

JO - CES Transactions on Electrical Machines and Systems

JF - CES Transactions on Electrical Machines and Systems

SN - 2096-3564

IS - 2

ER -