Efficient operation of LCL-filtered grid-connected photovoltaic inverters under uncertain grid conditions requires coordinated treatment of passive-filter and current-controller interactions. This study addresses the interaction mechanism between passive LCL network parameters and active controller parameters through a systematic simultaneous passive–active co-design framework for a 10 kW inverter. A controlled five-strategy M1–M5 comparison separates conventional, control-only, passive-network-only, sequential, and simultaneous designs under a common plant, delay, modulation, switching, FFT, and uncertainty-validation protocol. Multi-objective search is supported by fast physical indicators, while leakage-free Gaussian process regression is used only as a candidate-screening accelerator before direct switching verification. The selected M5 design achieves a switching-model current total harmonic distortion of 0.8004%, passive damping loss of 8.236 W, and nominal phase and gain margins of 59.13° and 8.13 dB, respectively. Across 1000 shared Monte Carlo samples, its strict acceptance ratio is 98.3%, with zero true discrete-pole instability; rejected samples are conservative all-crossover margin anomalies. These simulation-based results indicate that M5 provides a balanced engineering compromise among harmonic performance, damping loss, dynamic response, and robustness rather than a design that dominates every individual metric. Gaussian process regression reduces screening cost but neither defines the objective nor replaces high-fidelity validation. Hardware-in-the-loop and experimental validation remain future work.

Renewable energy and energy storage stations require frequent updates of monitoring and control logic across heterogeneous devices and changing operating strategies. This paper proposes a rule graph-based reference architecture that combines low-code logic configuration, graph–model semantic binding, and microservice-oriented functional decomposition. A component status matrix separates the target architecture from the implemented subset. The runnable subset comprises a minimal FastAPI backend, REST/WebSocket telemetry interfaces, an in-process queue, and stateful rule evaluators; gateway, authentication, external message bus, time-series database, visual editor, and industrial protocol services remain design-level elements. Beyond the original single-rule example, a priority-ordered multi-device rule is implemented for cooperative BESS dispatch, communication/topology blocking, low-SOC protection, frequency-based load shedding, backup request, and five-sample recovery release. Existing local network benchmarks are complemented by a 600-step software-in-the-loop trace with scripted telemetry fluctuations and communication quality faults and by 500 in-process ASGI timing samples at each of the four point levels. The trace produced no safety dispatch or protected device violations. P99 application path latency ranged from 1.1962 to 5.5287 ms, but one 75.3065 ms outlier exceeded a 50 ms reference deadline, demonstrating that the Windows/FastAPI path is not deterministic. No industrial controller, hardware-in-the-loop facility, field data, or engineer usability study was used. Accordingly, the paper makes no claim of industrial real-time readiness or measured development effort reduction.

Renewable power plants connected to low-system-strength grids are increasingly dominated by inverter-based resources (IBRs). Their point of common coupling (PCC) voltage is therefore shaped not only by reactive-power support but also by active-power ramps, network impedance, short-circuit capacity, and converter limits. Conventional Q-V droop control, fixed power-factor control, Volt/VAR control, and fixed active-power/reactive-power (P/Q) decoupling schemes often absorb active-power excursions into the voltage error, which can drive excessive reactive-power injection during fault clearing, post-fault power recovery, and phase-angle disturbances. Here, an active-power–voltage-coupling-aware reactive-power compensation (APVQ-RC) method is proposed for plant-level voltage control. The method estimates local P-V and Q-V voltage sensitivities online, reconstructs an effective voltage error, and produces a capacity-constrained reactive-power reference through smooth coupling activation. The reduced-order evaluation includes estimator conditioning, excitation screening, sensitivity-estimation error and empirical 95% estimator-error intervals, sensitivity to the smoothing factor and window length, measurement noise, converter capability saturation, and computational timing. Under P-V-coupled transients, APVQ-RC reduces voltage overshoot and reactive-power compensation energy while retaining Q-V-like support during voltage-sag-dominated events. Compared with the best scanned fixed P/Q baseline, it reduces overshoot, reactive-power compensation energy, and reactive-power peak by 42.03%, 60.35%, and 8.90%, respectively; the representative single-step calculation time is 0.0188 ms within a 1 ms control cycle. These results indicate millisecond-scale plant-level feasibility within the reduced model, while electromagnetic-transient, hardware-in-the-loop, and field validation remain necessary before deployment.

High penetrations of converter-interfaced wind and photovoltaic (PV) generation erode synchronous inertia and make plant-level frequency support increasingly dependent on time-varying active-power headroom. Here we propose a risk-credibility-recovery primary frequency regulation (RCR-PFR) strategy for wind–PV renewable energy stations. The controller maps frequency excursion and negative rate of change of frequency (RoCoF) to a bounded frequency-drop risk index, converts reserve margin, resource volatility, downward trend, ramp-rate feasibility, and saturation margin into an executable-reserve credibility index, and dispatches wind and PV support under capacity and ramp-rate constraints. A recovery-debt term retards premature support withdrawal, while a battery energy storage system (BESS) compensates only the residual demand that remains infeasible after wind–PV projection. In the standard load-step case, RCR-PFR raises the frequency nadir to 49.788 Hz, 0.132 Hz higher than the no-renewable-PFR case, and reduces the secondary frequency dip by 73.4% relative to fixed-ratio allocation. In a constrained-reserve stress case, H = 3.0 s denotes a low-equivalent-inertia condition and the 0.105 p.u. disturbance corresponds to a 105 MW load increase on a 1000 MVA base. Under this condition, residual BESS compensation raises the nadir from 49.595 Hz to 49.813 Hz, limits the maximum frequency excursion to 0.187 Hz, eliminates the 4.24 s low-frequency interval below 49.8 Hz, and reduces unmet support energy from 1.2324 MWh to 0.0114 MWh. These single-area simulations indicate that RCR-PFR can improve frequency-security margins, executable-reserve utilization, and withdrawal-stage stability, although multi-machine, electromagnetic-transient, hardware-in-the-loop, and field validation remain necessary before plant-level deployment.

Forecast-driven dispatch studies for renewable-storage microgrids can be weakened by feature leakage, non-receding dispatch windows, and inconsistent planned/realized evaluation scopes. This article presents a reproducible workflow-oriented low-code audit for an islanded photovoltaic (PV)-battery benchmark with secondary wind generation using public NASA Prediction Of Worldwide Energy Resources (POWER) weather and New York Independent System Operator (NYISO) load proxy data. The main direct multi-horizon forecast uses only calendar, lag, and rolling features; contemporaneous meteorological variables are reserved for a weather-informed diagnostic case. A mixed-integer linear programming (MILP) dispatch implemented with PuLP and COIN-OR Branch-and-Cut (CBC) enforces binary charge/discharge exclusivity, terminal battery state-of-charge (SOC) control, and true rolling-horizon execution in which each 24 h solve implements only the first action. All dispatch comparisons are filtered to the same 1694 complete forecast origins. On this common horizon, actual load totals 817.204 MWh and renewable availability totals 730.291 MWh. Relative to a rule-based baseline, the MILP reduces realized load shedding from 9.201 to 6.474 MWh and the normalized weighted objective from 10.769 to 8.203 million scenario-cost units. Weight, battery-capacity, renewable-penetration, and throughput-penalty analyses, together with bootstrap uncertainty intervals, show where this conclusion is robust and where it is benchmark-dependent. The contribution is an auditable evidence chain connecting public data, leakage-controlled forecasts, rolling-horizon dispatch, realized recourse accounting, generated figures/tables, and supplementary quality records; it is not a field validation or proprietary microgrid deployment study.

High penetration of converter-interfaced photovoltaic and wind generation reduces the effective inertia of islanded renewable energy systems and makes frequency stability more sensitive to load and renewable-power disturbances. This paper proposes a bounded adaptive droop framework for battery energy storage system (BESS) fast frequency response under low-inertia conditions, built around a bounded coordination mechanism. The framework coordinates frequency deviation, filtered rate of change of frequency (RoCoF), renewable-power fluctuation, and state of charge (SOC) to unify frequency-support capability with SOC availability and converter operating constraints. SOC-dependent available power limits, rated converter saturation, a ramp-rate limiter, RoCoF filtering, and measurement delay translate support demand into feasible power commands. A unit-consistent per-unit frequency-response model is combined with kW-level BESS power commands in MATLAB simulations. Compared with Fixed Droop, the proposed method reduces Max |Δf| and RMS Δf by 31.61% and 31.06%, respectively, on average across five deterministic cases, including four main disturbance cases and one charging case. In 30 Monte Carlo validation trials, the mean Max |Δf| decreases from 0.586 Hz to 0.330 Hz (43.66%), and the mean RMS Δf decreases from 0.416 Hz to 0.234 Hz (43.71%), with no SOC violation. Charging-protection tests further show that a fully charged BESS cannot absorb surplus renewable power, indicating the need for coordination with renewable curtailment, dump loads, secondary control, or reserve-SOC management.