• Journal of Power Electronics
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• v.16 no.3
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• pp.1190-1199
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• 2016

This study proposes a classification and compensation algorithm of two non-ideal output signals of a resolver to reduce position errors. Practically, a resolver generates position errors because of amplitude imbalance and quadrature imperfection between the two output signals of the resolver. In this study, a digital signal processor system based on a resolver-to-digital converter is used to reconstruct the two output signals of the resolver. The two output signals, "sin" and "cos," can be represented by a unit circle on the xy-plot. The classification and compensation of the errors can be obtained by using the radius and area of the circle made by the resolver signals. The method computes the integration of the areas made by the two resolver output signals to classify and compensate the error. This system cannot be applied during transient response given that the area integration during the transient state causes an error in the proposed method. The proposed method does not need any additional hardware. The experimental results verify the effectiveness of the proposed algorithm.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.3
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• pp.252-258
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• 2010

If the speed measurement of resolver and the generation of PWM signals are implemented with single microcontroller, it is easy to reduce the system cost and to avoid the switching noise of inverters. To avoid the switching noise and to improve the accuracy of measurement, PWM switching and A/D sampling of the resolver should be synchronized. Phase angle of the resolver excitation signal is increased in stepwise manner, then, the output signal of the resolver is measured in each step. From the measured data, the optimal phase angle of resolver excitation signal is estimated using the least square approximation method.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1310-1319
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• 2013

Resolvers are transducers that are used to sense the angular position of rotational machines. The analog resolver is necessary to use resolver to digital converter. Among the RDC software method, angle tracking observer (ATO) is the most popular method. In an actual resolver-based position sensing system, amplitude imbalance dominantly distorts the estimate position information of ATO. Minority papers have reported position error compensation of resolver's output signal with amplitude imbalance. This paper proposes new ATO algorithm in order to compensate position errors caused by the amplitude imbalance. There is no need premeasured off line data. This is easy, simple, cost-effective, and able to work on line compensation. To verify feasibility of the proposed algorithm, simulation and experiments are carried out.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.756-761
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• 2013

This paper propose the new demodulation method that can detect resolver signal's peak at the time of position estimation when the position information is required during current controller period. The proposed method is performed in a synchronous demodulation way with exciting signal and also cover a capability which can compensate the lag element of exciting signal caused by the resolver's inductive component and filter circuit. This paper carried out the experiment to investigate the validity and performance of the suggested method by using the test board made up of DSP and demodulation circuit. The test results show that the proposed method is theoretically clear and work completely as expected from making sure of sampling resolver signal's peak at the time of position estimation. In addition, Software position tracking algorithm is executed with the demodulated signals generated by the suggested method and an exact position can be estimated.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.192-200
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• 2018

In this study, improvements for error correction, speed, position, and rotation calculation algorithms have been proposed to be used in resolver to digital conversion (RDC) systems. The proposed open-loop system drives the resolver and uses the output signals of the resolver signal to estimate the real time position, the instant speed, and the rotation count with high resolution and accuracy even at high speeds and noise. The proposed solution implements strong features of both closed and open loop based systems while eliminating their weak points. The improvements proposed is resistant to noise owing to digital FIR filter and data averaging techniques. The implementation used for proof of concept is implemented on a hardware using an FPGA and configurable to be used by any resolver.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.146-152
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• 2016

This paper describes a multi-physics analysis of a high resolution winding type resolver and rotary transformer using FEM (Finite Element Method). The rotary transformer boosts the input voltage to a high voltage which can be input into the rotor windings of the resolver. Through multi-physics models of the transformer and resolver, the characteristics of the output signals for the resolver system with high resolution can be derived. Moreover, the circuit model of the interface part between the transformer and resolver should be considered, because of the calculation of the input current to the resolver. The winding type resolver is composed of 32x and 1x stator windings for high resolution. Then, the output signals of the stator windings, which make sinusoidal SIN and COS waves with a $90^{\circ}$ phase difference, are verified.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.497-500
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• 1987

A new concept in resolver-to-digital conversion is described, which is based on the digital phase locked loop(DPLL). This converter receives phase modulation and converts it into digital form using time ratio techniques. In this paper, the theories on DPLL and resolver and the design of the converter are covered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4569-4573
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• 2011

Resolver doesn't have a advantage to price in comparision with encorder. However, resolver is used to the case of detecting a absoluteness position and is used to a fine control in the place of having a stability by mechanic. The position by resolver and the method by speed detecting is applied by observer and have a part of processing analog signal. In this paper, we used the method which output signal of resolver is demodulated by cos and sin waveform and the demodulated analog signal is transmitted to controller. We designed the estimated on the program of a controller and observed the movement on the low speed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4550-4560
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• 2011

Generally, a optical encoder is used to detect velocity for controling the electronic motor, the resolver is used when it is hard structurally to adjust encoder to electronic motor. so, the resolver has weakness in price in compare with encoder, but in case of controling the position of a magnetic polar, the resolver has stead detecting the absolute position of a rotator. This study is about the digital programing velocity detector which uses a minimum hardware : filter for detecting the revolve speed and rotor position of the motor by means of the resolver.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1406-1409
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• 2004

The Resolver usually used in industry is the absolute angle analog sensor that must be in order to driving BLDC (brushless DC) motor, and it needs RDC(Resolver-to-Digital converter) for changing the output signal to digital to be applied to the SVPWM(Space Vector Pulse Width Modulation) algorithm. Commonly used S/W RDC needs trigonometric function. What it takes a lot of calculation time of processor is gotten at weak point. In this paper, S/W RDC is realized except trigonometric functions as a result of feedback resolver outputs after filtering using FIR filter. thus, processing time is reduced. So, One-chip DSP Controller operating the Vector Control, RDC, and SVPWM can be designed.