Research and practice of three-phase signal source design based on DDS technology

In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.

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Digital controller for active power filter based on P-Q theory under non-ideal main voltages

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v12.i3.pp1556-1565 ◽

2021 ◽

Vol 12 (3) ◽

pp. 1556

Author(s):

Moh. Jauhari ◽

Mohammad Nur ◽

Kukuh Widarsono

Keyword(s):

Control Strategy ◽

Active Power Filter ◽

Active Power ◽

Digital Controller ◽

Test Results ◽

Power Filter ◽

Q Theory ◽

Three Phase ◽

Reference Current Generation ◽

Phase Signal

<span>This paper proposes a control strategy active power filter under non-ideal main voltages. The P-Q Theory is used to generate three-phase active power filter reference currents, but the P-Q Theory has a weakness when implemented under non ideal main voltages. This paper proposes a reference current generation method using modified P-Q Theory under non-ideal main voltages conditions. Before calculating the P-Q Theory, the non-ideal voltage at the source is normalized by using PLL to determine the phase angle which is then carried out by generating an ideal three-phase signal. The proposed method is simulated and implemented in a three-phase active power filter controller. The test results show the improvement in the performance of the P-Q Theory under non ideal main voltages with THD 7.21% to THD 3.29%.</span>

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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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