Power systems
Mahdi HassanniaKheibari; Zivar Rigi
Abstract
As power systems rapidly expand and the demand for uninterrupted power supply to network loads increases, ensuring the safe and stable operation of these systems has become crucially important. However, conducting dynamic stability assessments with detailed dynamic models is nearly impossible in today’s ...
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As power systems rapidly expand and the demand for uninterrupted power supply to network loads increases, ensuring the safe and stable operation of these systems has become crucially important. However, conducting dynamic stability assessments with detailed dynamic models is nearly impossible in today’s complex power networks. The introduction of Phasor Measurement Units (PMUs) has paved the way for new stability evaluation techniques that rely on real-time measurement data. A common limitation of most measurement-based techniques is their vulnerability to noise in the data. While some newer methods offer improved noise resistance, they are often hindered by high computational demands and slow processing times, limiting their practical use. This paper developed a measurement-based method that uses power spectral density (PSD) and cross-spectral density (CSD) to achieve a more precise estimation of low-frequency oscillations in power systems. Simulation results on the IEEE 14-bus and 39-bus test systems, tested under both noisy and noise-free conditions, show that the proposed method yields more accurate frequency and oscillation shape estimates, even when measurement noise is present. Additionally, the Prony algorithm, a well-known measurement-based method, is also implemented, and its high sensitivity to noisy data is demonstrated.
Industrial Electronics
Mohammad Ali Heydari; Mahdi HassanniaKheibari; Gholamreza Sadeghi
Abstract
Active power filters (APFs) play a vital role in reducing the current harmonics and improving power quality. This work studies a shunt APF (SAPF) based on the three-phase voltage source converter (VSC). This paper investigates the new robust control approach using error dynamics. Stable first-order error ...
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Active power filters (APFs) play a vital role in reducing the current harmonics and improving power quality. This work studies a shunt APF (SAPF) based on the three-phase voltage source converter (VSC). This paper investigates the new robust control approach using error dynamics. Stable first-order error dynamics are considered when designing the control inputs. Three control inputs are obtained to control the currents at any phase by choosing and optimizing the appropriate parameters. This strategy is also simple to implement in practical applications because it is the same as the proportional-derivative controller design. In addition, the new control method can be utilized for any system with low dynamic information so that the destructive effects of lumped uncertainties in the output channels of the SAPF can be alleviated. The minimum voltage and current measurements are used to control the SAPF, and the grid current harmonics will be reduced by achieving the stabilization of tracking error dynamics. Some numerical simulations are performed by MATLAB software to confirm the proposed method.
