Accuracy Improvement in Resolver Offset Detection Based on Angle Tracking Observer with Coordinate Transformation

It is necessary to obtain the rotor position of the Interior Permanent Magnet Synchronous Motor (IPMSM) for instantaneous torque control in an electric vehicle system. A resolver is mostly used as a rotor position sensor, each motor has a resolver offset according to the fit tolerance of the resolver pressed into the rotor shaft when the motor is manufactured. This resolver offset is having a huge effect on IPMSM output characteristics. Therefore, resolver offset detection equipment with a method for high precision of detection is required in production lines in order to make uniform characteristics of IPMSM. It is also necessary to have robust performance in many different kinds of the noise of equipment in the production line. This paper presents a highly precise Resolver to Digital Converter (RDC) that is implemented with LabVIEW of National Instruments and a resolver offset detecting method that has the robust performance to noise based on coordinate transformation algorithm. Experiments with and without the proposed method were performed and a comparative analysis is conducted to test the validity.

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Improved ANFIS based MRAC observer for sensorless control of PMSM

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189772 ◽

2021 ◽

pp. 1-13

Author(s):

Suryakant ◽

Mini Sreejeth ◽

Madhusudan Singh

Keyword(s):

Fuzzy Inference ◽

Permanent Magnet Synchronous Motor ◽

Torque Control ◽

Control Algorithms ◽

Motor Speed ◽

Inference System ◽

Rotor Position ◽

Improved Performance ◽

Incremental Encoder ◽

Model Reference Adaptive

Detection of the rotor position is an important prerequisite for controlling the speed and developed torque in permanent magnet synchronous motor (PMSM). Even though use of incremental encoder and resolver is one of the popular schemes for sensing the rotor position in a PMSM drive, it increases the size and weight of the drive and reduces its reliability. Dynamic modeling of the motor and control algorithms are often used in sensor-less control of PMSM to estimate rotor position and motor speed. Most sensor-less control algorithms use machine parameters like torque constant, stator inductances and stator resistance for estimating the rotor position and speed. However, with accuracy of such estimation and the performance of the motor degrades with variation in motor parameters. Model reference adaptive control (MRAC) provides a simple solution to this issue. An improved Adaptive neuro-fuzzy inference system (ANFIS) based MRAC observer for speed control of PMSM drive is presented in this paper. In the proposed method adaptive model and adaptive mechanism are replaced by an improved ANFIS controller, which neutralize the effect of parametric variation and results in improved performance of the drive. The modeling equations of PMSM are used to estimate the rotor position for speed and torque control of the drive. Simulation studies have been carried out under various operating condition using MATLAB/Simulink. In addition, a comparative analysis of the conventional MRAC based observer and improved ANFIS based MRAC observer is carried out. It is observed that the proposed method results in better performance of the PMSM drive.

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Sensorless Control of IPMSM Using Modified Current Slope Estimation Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.150.100 ◽

2012 ◽

Vol 150 ◽

pp. 100-104

Author(s):

Tao Zhang ◽

Wei Ni ◽

Hui Ping Zhang ◽

Sha Sha Wu

Keyword(s):

Permanent Magnet ◽

Digital Signal Processor ◽

Permanent Magnet Synchronous Motor ◽

Estimation Method ◽

Digital Signal ◽

Synchronous Motor ◽

Low Speed ◽

Rotor Position ◽

Operating Region ◽

Interior Permanent Magnet

When the permanent magnet synchronous motor is operated at a low speed. The rotor position and speed are very difficult to estimate using the extended flux or back EMF method. A novel modified current slope estimating method is used to estimate the rotor position and speed in low speed in this paper. The mathematical models of an interior permanent magnet synchronous motor (IPMSM) are deduced. The basic principle of modified current slope method is introduced. The simulation control system is built based on Matlab and a TMS320LF2407 digital signal processor is used to execute the rotor position and speed estimation. The experimental and simulation results have shown that the rotor position and speed can be accurately estimated in a low-speed operating region.

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