Three-phase signal generation from a single-phase reference signal

This paper presents a novel frequency-locked-loop (FLL) scheme that provides estimates of the in-phase and square-phase fundamental components of a distorted single-phase reference signal and an estimate of its fundamental angular frequency. The main feature of the proposed scheme is that its design is fully based on the dynamical model of a single-phase signal generator, namely, the second-order harmonic oscillator (SOHO), which adds originality to the scheme. In fact, the proposed scheme owns a particular structure involving a set of orthogonal signals, which can be seen as the fixed-frame representation of three-phase balanced signals. Additionally, a plug-in block is included as a mechanism to mitigate the effect of the harmonic distortion. A proof of global stability for the proposed scheme based on nonlinear argumentation is also included, which contributes to the novelty of the work and ensures convergence disregarding the initial conditions of the to-be-estimated signal components. In addition, explicit conditions are presented for the tuning of control parameters. Experimental results corroborate the performance of the proposed scheme under angular frequency variations, phase jumps, voltage sags and harmonic distortion on the reference signal. For comparison purposes, also the state-of-the-art second-order-generalized-integrator-based FLL and the single-phase synchronous-reference frame phase-locked loop are tested.

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Quaternion-valued single-phase model for three-phase power system

Journal of Electrical Engineering ◽

10.2478/jee-2018-0023 ◽

2018 ◽

Vol 69 (2) ◽

pp. 183-186

Author(s):

Xiaoming Gou ◽

Zhiwen Liu ◽

Wei Liu ◽

Yougen Xu ◽

Jiabin Wang

Keyword(s):

Power Systems ◽

Single Phase ◽

Harmonic Distortion ◽

Minimum Variance ◽

Music Algorithm ◽

Three Phase ◽

Minimum Variance Distortionless Response ◽

Zero Sequence ◽

Phase Signal ◽

The Fourier Transform

Abstract In this work, a quaternion-valued model is proposed in lieu of the Clarke’s α, β transformation to convert three-phase quantities to a hypercomplex single-phase signal. The concatenated signal can be used for harmonic distortion detection in three-phase power systems. In particular, the proposed model maps all the harmonic frequencies into frequencies in the quaternion domain, while the Clarke’s transformation-based methods will fail to detect the zero sequence voltages. Based on the quaternion-valued model, the Fourier transform, the minimum variance distortionless response (MVDR) algorithm and the multiple signal classification (MUSIC) algorithm are presented as examples to detect harmonic distortion. Simulations are provided to demonstrate the potentials of this new modeling method.

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Park’s Transformation for Electric Power Quality Recognition and Classification in Distribution Networks

International Journal of System Dynamics Applications ◽

10.4018/ijsda.2012040105 ◽

2012 ◽

Vol 1 (2) ◽

pp. 60-79 ◽

Cited By ~ 4

Author(s):

Ahmad M. AL Kandari ◽

Jamal Y. Madouh ◽

Soliman A. Soliman ◽

Rashid A. Alammari

Keyword(s):

Power Quality ◽

Time Domain ◽

Single Phase ◽

Distribution Networks ◽

Voltage Sags ◽

Three Phase ◽

Electric Power Quality ◽

Voltage Swell ◽

Phase Signal ◽

Novel Algorithm

This paper presents a novel algorithm for recognizing and classifying the power quality events based on Park’s transformation, where the three rotating abc phases are transferred to three equivalent stationary dq0 phases (d-q reference frame). This transformation is implemented, either for three-phase or single phase circuits. The proposed algorithm transferred the utility signal to a complex phasor (transformation from time domain to frequency domain). The magnitude of this phasor depends on the magnitude of the signal either a three-phase or a single phase signal. The proposed technique produces the complex phasor loci that depend on the type of power quality event; voltage sags, voltage flickers, voltage swell, and harmonics. The time of starting the disturbance is chosen randomly and the length of disturbance is arbitrary. Implementation of this technique is succeeded in recognizing and classifying the power quality events. Simulated results are presented within the text, for three-phase and single phase events.

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