Peak detection in physiological signals is fundamental to biomedical signal processing, yet existing methods exhibit systematic performance degradation under non-stationary conditions: fixed-threshold methods suffer precision-recall drops exceeding 30
This article proposes a discrete-time state-space voltage control strategy employing dual complex-variable resonant controllers (CVRCs) for voltage source inverters (VSIs) equipped with output LC filters. Designed directly in the discrete-time domain, the proposed controller simultaneously regulates positive- and negative- sequence components in the stationary reference frame to enhance system stability and control precision under unbalanced conditions. The control law integrates both state feedback and feedforward terms while explicitly accounting for the LC filter resonance and the intrinsic digital delay in PWM inverters. By applying the dominant pole elimination (DPE) method, the proposed control structure effectively eliminates dominant dynamic components, thereby improving both reference voltage tracking performance and load current disturbance rejection capability. Furthermore, the direct discrete-time domain design ensures robust operation even in systems with a low sampling frequency. Frequency-domain analysis confirms that the proposed voltage controller not only achieves a wide control bandwidth but also provides superior stability margins compared to conventional continuous-time controllers. Finally, the effectiveness of the proposed control strategy is validated through experimental results, demonstrating its superior performance for high-performance AC voltage-controlled applications.
This paper proposes an improved equivalent circuit analysis (ECA) method for interior permanent magnet synchronous motors (IPMSMs) under maximum torque per ampere (MTPA) control. Precise estimation of inductance and no-load flux linkage is essential for accurate ECA. However, the conventional vector control method (VCM) exhibits two major limitations. First, the d-axis current in the denominator approaches zero near a current phase angle of 90°, leading to a mathematical discontinuity in the d-axis inductance calculation. This discontinuity reduces interpolation reliability and performance analysis accuracy. Second, using a fixed no-load flux linkage obtained from finite element analysis (FEA) fails to reflect the magnetic saturation caused by load variations. To overcome these limitations, this study proposes an incremental method (IM) that derives a continuous d-axis inductance utilizing FEA results from adjacent load conditions. Furthermore, based on the derived inductance, a load-dependent no-load flux linkage is calculated to reflect the nonlinearity of the magnetic circuit. By applying the proposed parameters to the MTPA-based ECA, the prediction error was reduced to within 0.3
This paper presents a comparative assessment of Grid-Following (GFL) and Grid-Forming (GFM) control strategies for STATCOM applications in weak grids. The analysis demonstrates that conventional GFL devices are fundamentally limited by their Phase-Locked Loop (PLL) synchronization mechanisms. To overcome these synchronization limitations, this study evaluates GFM STATCOMs that maintain an internal voltage reference and exhibit voltage-source-behind-impedance behavior, thereby contributing to local voltage stiffness and system strength. By adopting a quantification framework aligned with the National Renewable Energy Laboratory (NREL) GFM performance testing methodology, the proposed approach benchmarks a GFM STATCOM as an ideal voltage source behind an impedance. The dB-referenced admittance obtained from the scan is converted into a linear admittance and then into an SI-unit ohmic equivalent impedance, from which the before-and-after system strength improvement is computed to quantify the system strength reinforcement provided by the GFM STATCOM. The effectiveness of this reinforcement is validated through electromagnetic transient (EMT) simulations on both a 3-bus equivalent system and a benchmark model of the Honam regional grid.
This paper presents an extended Power over Data Lines (PoDL) system for automotive Single-Pair Ethernet (SPE) applications. As autonomous vehicles require an increasing number of sensors and electronic modules, reducing cable weight and wiring complexity while ensuring reliable power and data transmission has become essential. Although IEEE 802.3bu defines PoDL for SPE systems, its conventional power range is limited for high-power automotive devices. The proposed system delivers up to 35 W through an SPE cable and is experimentally evaluated under various cable lengths, power sourcing equipment (PSE) supply voltages, and powered device (PD) load conditions. Voltage drop, power loss, power efficiency, packet loss, and communication latency are measured to assess system performance. Experimental results show that the proposed system achieves power efficiencies from 87.42
