Continuous Output Research Articles

Characteristics of Combustion and NOx Emission in a 600 MWe Wall-Fired Boiler Under Varying Coal Mill and Burner Damper Configurations

ABSTRACT To accelerate China’s transition toward providing capacity support and prioritizing electricity generation, detailed research is necessary regarding the continuous peak output of coal-fired boilers during peak periods. However, high-load operation of coal-fired boilers may lead to issues such as NOx emission and increased flue gas temperature. This study conducted industrial experiments on a 600 MWe wall-fired boiler operating under peak conditions (500 MWe), using different pulverized coal mill operating modes. The boiler was optimized by adjusting the damper openings of the burners. Experimental results showed coal powder ignited within 0.2 m of burner outlets, indicating good performance. With the reduction in the damper openings of the burners, the concentration of NOx decreased, and the flue gas temperature gradually dropped, with the maximum temperature differential being 179°C. The ABCEF pulverized coal mill case had high water consumption and flue gas loss, unfavorably affecting economic operation. The ABDEF case delayed temperatures by 100°C, with the lowest NOx concentration at 277 ppm, enhancing environmental friendliness. In addition, the ABCDE case exhibited optimal coal burnout, with 0.838% fly ash carbon content, and the lowest flue gas temperature at 111.49°C, reducing flue gas loss by 5.9% compared to the ABDEF case, showing good economic performance.

Self-frequency-doubling Yb:GdCOB laser intracavity-pumped Pr:YAP laser

Abstract We present for the first time a Pr:YAlO3 (Pr:YAP) laser emitting at 547 nm intracavity-pumped by a self-frequency-doubling Yb3+:Ca4GdO (BO3)3 (Yb:GdCOB) blue laser at 488 nm. We carried out a model to design the system properly, and the laser performance was experimentally investigated. Intracavity sum-frequency mixing at 547 and 488 nm was then realized in a CsLiB6O10 (CLBO) nonlinear crystal to reach the ultraviolet laser at 258 nm. We obtained a continuous wave output power of 575 mW at 258 nm with a pump source, which is a diode-pumped quasi-three-level Sr1-x La x -y Nd y Mg x Al12-x O19 (Nd:ASL) laser emitting 11.2 W at 902 nm.

Fixed-time second-order sliding mode output feedback trajectory tracking control for an autonomous surface vehicle with model uncertainties and prescribed performance

This paper investigates the fixed-time trajectory tracking control problem of autonomous surface vehicle system with asymmetric performance constraints. The external disturbances, model uncertainties and the difficulty of velocity measurement are all taken into account in the controller design. Asymmetric performance constraints are firstly studied to improve the transient and steady-state performance of the tracking error system. Next, a fixed-time extended state observer is developed to estimate the unknown velocity and external disturbances. Both the fixed-time first-order and the second-order PID-type sliding surfaces are designed. Further, two continuous output feedback controllers are built to achieve high control accuracy and low energy consumption and to achieve fixed-time stability of the closed-loop system. Finally, abundant simulations for CyberShip II demonstrate the effectiveness of the proposed algorithms.

Design and implementation of a solar power optimizer for module level power electronics application

AbstractPartial shading on series‐connected photovoltaic (PV) panels in conventional PV systems results in lower harvested power. To resolve this, it is vital to utilize module level power electronics (MLPE) such as Solar Power Optimizers (SPOs). This paper introduced a non‐isolated common ground non‐inverting output voltage buck‐boost converter as an SPO. Proposed converter benefits from continuous input and output currents which has a significant role in designing SPOs. Having a quadratic gain, beside acceptable step‐down range are other features of the converter. Operating principle, design, steady‐state, small‐signal analysis, and dynamic performance of proposed converter are included. Proposed converter is compared with other buck‐boost converters in terms of voltage gain, voltage stresses, continuous input and output current, and output polarity. To validate the performance of introduced converter, experimental results for a prototype with input voltage 24 V, output voltage 72 V for step‐up and 15 V for step‐down modes are given and results are examined. The maximum efficiency of the prototype is 93% and 89% for step‐up and step‐down modes, respectively. To evaluate the effect of proposed SPO for extracting maximum available power from PVs, simulation results of a grid connected PV system with two series connected SPOs is discussed.

Analysis and Design of a Battery and Supercapacitor‐Based Propulsion System for Electric Vehicles

ABSTRACTThis work deals with the design and development of a dual source based propulsion architecture for electric vehicles. The converter utilized for the propulsion system is derived from a conventional CuK converter, which operates in a bidirectional power flow mode. The proposed propulsion system has two energy sources: a battery and a supercapacitor (SC). The proposed system has continuous input and output currents at low and high voltage sides, which improves the cycle life of hybrid energy storage (SC and battery) and the DC‐link capacitor. Further, the proposed converter has magnetic reduction compared to a conventional two‐input bidirectional CuK converter. Moreover, an effective and simpler control strategy (only one switch is pulse width modulated (PWM) operated at a time) has been developed for energy management between sources during charging (regenerative braking) and discharging (propulsion), which is effectively verified by simulation and experimental results. Further, a frequency domain (bode plot)‐based technique is used for controller design and stability analysis of the proposed system.

Pulse index contour continuous cardiac output (PICCO) monitoring in critically ill patients.

Objective: To evaluate the utility of Pulse index Contour Continuous Cardiac Output (PiCCO) monitoring in critically ill patients. Study Design: Cross-sectional study. Setting: Intensive Care Unti of Sindh Institute of Urology and Transplant, Karachi, Pakistan. Period: October 2022 to March 2023. Methods: Patients presenting with various types of shock, requiring high-dose vasopressors or inotropes, and not responding to initial fluid therapy were analyzed. Demographic details, SOFA score, APACHE score, and invasive hemodynamic parameters using the PiCCO system were documented. Results: Out of 142 ICU admissions, 38 patients were included in the study. Most patients were males (73%) with a median age of 39 years. Significant changes were observed in the cardiac index, cardiac performance index, global ejection fraction, and systemic vascular resistance index (SVRI), all with p-values less than 0.05. The interventions included the initiation of inotropes in 22 patients (57.8%), diuretics in 4 patients (10.5%), and intravenous fluids in 19 patients (50%). Additionally, vasopressor doses were adjusted in 18 patients (47.3%). Initially, patients were presumed to have pure septic shock based on CO2 gap, mixed venous saturation, and echocardiographic assessment. However, after applying PiCCO monitoring, the diagnosis was revised to mixed shock in 21 patients (55.2%). Conclusion: PiCCO monitoring appears to be a valuable tool in the ICU for managing patients with complex hemodynamic profiles, facilitating targeted interventions that lead to significant improvements in hemodynamic stability.

Infrared non-uniformity correction method based on binocular detection system without blindsight

The output image of an infrared detector often suffers from non-uniformity due to the inhomogeneity of the device material and limitations in the manufacturing process, which can reduce the detector's capability to detect and identify targets. It is therefore necessary to adequately correct the non-uniformity to fully utilize the high temperature sensitivity of the detector. Calibration-based non-uniformity correction technology is one of the earliest and most effective methods of correcting non-uniformity. Typically, a relatively uniform shutter is used to mask the field of view for calibration correction. However, this process interrupts the observation due to the need for masking, severely limiting its use in real-world projects. In order to maintain the performance superiority of the calibration-based method and eliminate the defect of target loss caused by masking, this paper takes the occlusion calibration as the theoretical basis, which consists of dual detectors to form a binocular detection system, and uses one of the occluded calibration auxiliary detector to assist the other occlusion-free primary detector, and takes advantage of the fact that the radiation is the same when observing the same target at the same time to make the correct response based on the steepest gradient descent learning algorithm, which removes the non-uniformity while achieving detail fidelity, no ghosting and continuous output.

A new aerosol delivery approach for enhanced long-term respiratory care in resource-poor settings

Continuous aerosol therapy is safe, superior, and the mainstay in the therapy of patients with severe asthma, cystic fibrosis, chronic obstructive pulmonary disease (COPD), and coronavirus disease (COVID-19). However, continuous nebulization has been perceived as highly expensive and labor-intensive, which often requires specialized medical equipment. Moreover, it is difficult to maintain consistent aerosol output and particle size delivery over an extended period without operator intervention. This work proposes a simple and reliable continuous nebulization method using a conventional gas jet nebulizer and intravenous (IV) bottle/bag. The present work reports detailed experimental studies on a gas jet nebulizer with Particle image velocimetry (PIV), Particle/droplet Imaging Analysis (PDIA), and Mie scattering techniques to demonstrate the feasibility of the proposed technique. The preliminary investigation shows that the proposed method provides continuous liquid output delivery without external supervision. The liquid delivery rate and mass median diameter (MMD) of the nebulizer mainly depend on the gas flow rate and suction height. The MMD of the primary generated droplets is reported to vary between 100 and 230 μm for a ± 10 cm suction height and 500–1000 mlph nebulization gas flow rate. Most importantly, the nebulizer spray angle, stability, droplet size distribution, and the axial and radial velocities of the droplets are marginally affected by the suction height. Therefore, the proposed system is a versatile, safe, and cost-effective method of continuous nebulization therapy, especially in resource-poor countries or contagious disease outbreak situations.

Beneficial effects of extravascular lung water index-guided volum management in patients with cardiogenic shock

Objective: To evaluate the role of volume management guided by extravascular lung water index(EVLWI) in improving the clinical outcomes and cardiac function for patients with cardiogenic shock. Methods: This study was a single-center, prospective cohort study. Patients with cardiogenic shock admitted to the Department of Cardiovascular Medicine, Shanghai East Hospital from July 2022 to December 2023 were enrolled. Patients were matched 1∶1 by propensity score and divided into EVLWI group and control group. In the control group, the volume management strategy was determined by the attending physician based mainly on conventional factors, including clinical features, biochemical assessments, and certain blood pressure measurements. In EVLWI group, the volume management plan was formulated by integrating conventional factors with EVLWI derived from pulse index continuous cardiac output (PiCCO) monitoring. Baseline clinical data, in-hospital treatment, and hemodynamic data were collected. Major adverse cardiovascular events and cardiac function related parameters were compared at 30 d after treatment between the two groups. Baseline EVLWI levels were compared between the non-survivors and the survivors in the EVLWI group. The receiver operating characteristic curve was plotted to assess the accuracy of baseline EVLWI and central venous pressure in predicting all-cause mortality at 30 d after treatment in patients with cardiogenic shock, and subgroup analysis was performed according to ischemic/non-ischemic etiology and with/without use of inotropic drugs. Kaplan-Meier curve was used for survival analysis, with log-rank tests comparing all-cause mortality, cardiac death, and readmission rate for heart failure at 30 d after treatment. Results: A total of 200 patients with cardiogenic shock were enrolled, aged (71.35±12.82) years, 144(72%) males, EVLWI group and control group 100 patients each. Compared with the control group, EVLWI group had lower all-cause mortality (16%(16/100) vs. 42%(42/100), log-rank P<0.01), cardiac death (14%(14/100) vs. 34%(34/100), log-rank P<0.01), and readmission rate for heart failure (4%(4/100) vs. 12%(12/100), log-rank P=0.03) at 30 d after treatment. Subgroup analysis showed that EVLWI-guided volume management was associated with lower all-cause mortality at 30 d after treatment in patients with cardiogenic shock of ischemic or non-ischemic etiology and with or without inotropic drugs (all P<0.05). In EVLWI group, baseline EVLWI levels were higher in non-survivors than those in survivors [(15.99±6.47) ml/kg vs.(9.75±2.55) ml/kg, P<0.01]. The baseline EVLWI could predicting all-cause mortality at 30 d after treatment in patients with cardiogenic shock, with an area under the receiver operating characteristic curve of 0.84 (95%CI: 0.75-0.94, P<0.01), while the baseline central venous pressure had no predicting value (AUC=0.54, 95%CI: 0.40-0.69, P=0.60). The optimal cutoff value of EVLWI in pridicting all-cause mortality at 30 d after treatment in patients with cardiogenic shock was >10.3 ml/kg. With the optimization of hemodynamic parameters, left ventricular ejection fraction was improved in EVLWI group, and serum levels of N-terminal pro-brain natriuretic peptide, creatinine, alanine aminotransferase and lactic acid were decreased (all P<0.05). Conclusion: EVLWI-guided volume management exerts a beneficial effect on therapeutic decision-making and improves clinical outcomes and cardiac function in patients with cardiogenic shock.

A new positive output DC–DC buck–boost converter based on modified boost and ZETA converters

A new DC–DC buck–boost converter with a wide conversion ratio is presented in this paper. The proposed buck–boost converter consists of a combination of modified boost converter and ZETA converter, which has the advantages of both converters such as continuous input/output current and positive polarity of the output voltage. The combination of these two converters achieves semi-quadratic voltage gain and makes the proposed converter suitable for industrial and renewable energy applications. With a voltage gain higher than that of the ZETA converter and modified boost converter, the proposed converter also reduces input current stress due to its continuity. Two operating states are available for this converter in continuous conduction mode. This converter has two switches that operate simultaneously and can be easily controlled. The converter's output voltage ripple and output capacitor current stress are reduced as a result of continuous output current. Computational analysis and the introduced structure efficiency considering the influence of parasitic elements are presented in this paper. The small signal modelling and closed-loop control, as well as simulation and experimental results are also presented. This converter has also been compared with other similar and recently presented topologies. Finally, a 40–60 W, 20–76 V for boost mode and 10 V for buck mode prototype was implemented to verify the accuracy of the computational analysis.

Evaluation of the Noninvasive Estimated Continuous Cardiac Output System for Pediatric Patients: A Prospective Observational Study.

The estimated continuous cardiac output (esCCO) system is a hemodynamic monitor that uses electrocardiograms and pulse oximeter waves to noninvasively estimate cardiac output. The coefficients for esCCO measurement have been established for adult patients, but the appropriate coefficients for pediatric patients are unclear. Therefore, this study determined esCCO coefficients for pediatric patients and validated the accuracy and tracking ability of a modified esCCO system. An initial study compared cardiac output measurements using transthoracic echocardiography and esCCO in 60 pediatric patients aged <15 years who underwent elective noncardiac surgery. Consequently, the coefficients for the esCCO measurements were redefined for pediatric patients. The main study compared cardiac output measurements between transthoracic echocardiography and modified esCCO in 80 pediatric patients. Measurements were performed pre- and postoperatively, and the accuracy and trending ability of the cardiac output measurements were evaluated using Bland-Altman analysis and a polar plot. The correlation coefficients between the modified esCCO and transthoracic echocardiography were 0.96 and 0.98 in the pre- and postoperative measurements, respectively. In Bland-Altman analysis, the bias (standard deviation [SD]), 95% limits of agreement, and percentage error were 0.03 (0.28), -0.53 to 0.60, and 18% in the preoperative measurement, and -0.04 (0.19), -0.42 to 0.35, and 15% in the postoperative measurement, respectively. The polar plot showed that the cardiac output changes were well tracked, with an angular bias (SD) of 2.9° (6.0°) and radial 95% limits of agreement ranging from -9.2° to 14.9°. Cardiac output measurement by esCCO with modified coefficients for pediatric patients showed high accuracy and tracking ability compared with cardiac output measurement by transthoracic echocardiography. This noninvasive cardiac output measurement could benefit perioperative hemodynamic monitoring in children.

A Pilot and Feasibility Study of Continuous Cardiac Output and Blood Pressure Monitoring during Intermittent Hemodialysis

Introduction: Hypotension is common during intermittent hemodialysis (IHD) and may be due to a decreased cardiac index (CI). However, no study has simultaneously and continuously measured CI and mean arterial pressure (MAP) to understand the prevalence, severity, and duration of CI decreases or relate them to MAP, blood volume (BV), and net ultrafiltration (NUF) rate. Methods: In a prospective, pilot and feasibility investigation, we studied 10 chronic IHD patients. We used the ClearSight System™ to continuously monitor CI and MAP; the CRIT-LINE®IV monitor to detect BV changes and collected data on NUF rate. Results: Device tolerance and compliance were 100%. All patients experienced at least ≥1 episode of severe CI decrease (>25% from baseline), with a median duration of 24 min (IQR 6–87) and of 68 min [14–106] for moderate decreases (>15% but ≤25% from baseline). Eight patients experienced a low CI state (<2.2 L/min/m2). The lowest CI was 0.9 L/min/m2 with a concomitant MAP of 94 mm Hg. When the fall in CI was severe, MAP increased in 58% of cases and remained stable in 28%. Overall, CI decreased by −0.55 L/min/m2 when BV decrease was moderate versus mild (p < 0.001) and by −0.8 L/min/m2 when NUF rate was high versus low (p < 0.001). Conclusion: Continuous CI monitoring is feasible in IHD and shows frequent moderate-severe CI decreases, sometimes to low CI state levels. Such decreases are typically associated with markers of decreased intravascular volume status but not with a decrease in MAP, implying marked vasoconstriction.

Clinical Effect of Norepinephrine Combined with Esmolol Treatment in Patients with Septic Shock and Its Impact on Prognosis.

To unveil the influence of norepinephrine (NE) combined with esmolol treatment on cardiac function, hemodynamics, inflammatory factor levels, and prognosis in patients with septic shock. Ninety-six patients with septic shock admitted to our hospital from January 2021 to June 2023 were retrospectively analyzed and divided into the control and observation groups according to the different treatment methods. The control group was treated with standard anti-infection and fluid resuscitation, followed by NE administration [with an infusion rate of 0.1-0.5 μg/(kg-min)]. The observation group was treated with esmolol [starting pumping rate of 50 μg/(kg-min) and adjusting the pumping rate according to the target heart rate] in combination with the control group. Changes in hemodynamic parameters, including heart rate, mean arterial pressure, central venous pressure, cardiac index, stroke volume index, and systemic vascular resistance index, were monitored by pulse-indicating continuous cardiac output monitors before treatment (T0), 24h after treatment (T1), and 72h after treatment (T2); changes in cardiac function before and after 72h of treatment, indicators of inflammatory factors before and after treatment, and indicators of oxygenation metabolism were assessed; and adverse drug reactions during treatment were recorded in both groups. NE combined with esmolol treatment improved the efficacy of patients with septic shock; was beneficial for the enhancement of blood perfusion in patients; improved the patient's cardiac function, reduced myocardial injury, and suppressed the inflammatory response in patients; improved the oxygenation metabolism and the prognosis of patients; did not significantly increase the adverse drug reactions of patients and had a better safety profile. NE combined with esmolol treatment can improve the efficacy of patients with septic shock, improve their cardiac function and hemodynamic indices, reduce myocardial injury and inflammatory response, and have a better safety profile, which is conducive to improving patient prognosis and reducing mortality.

Occurrence of Low Cardiac Index During Normotensive Periods in Cardiac Surgery: A Prospective Cohort Study Using Continuous Noninvasive Cardiac Output Monitoring.

Continuous cardiac output monitoring is not standard practice during cardiac surgery, even though patients are at substantial risk for systemic hypoperfusion. Thus, the frequency of low cardiac output during cardiac surgery is unknown. We conducted a prospective cohort study at a tertiary medical center from July 2021 to November 2023. Eligible patients were ≥18 undergoing isolated coronary bypass (CAB) surgery with the use of cardiopulmonary bypass (CPB). Cardiac output indexed to body surface area (CI) was continuously recorded at 5-second intervals throughout surgery using a US Food and Drug Administration (FDA)-approved noninvasive monitor from the arterial blood pressure waveform. Mean arterial blood pressure (MAP) and central venous pressure (CVP) were also analyzed. Low CI was defined as <2 L/min/m2 and low MAP as <65 mm Hg. We calculated time with low CI for each patient for the entire surgery, pre-CPB and post-CPB periods, and the proportion of time with low CI and normal MAP. We used Pearson correlation to evaluate the relationship between CI and MAP and paired Wilcoxon rank sum tests to assess the difference in correlations of CI with MAP before and after CPB. In total, 101 patients were analyzed (age [standard deviation, SD] 64.8 [9.8] years, 25% female). Total intraoperative time (mean [SD]) with low CI was 86.4 (62) minutes, with 61.2 (42) minutes of low CI pre-CPB and 25.2 (31) minutes post-CPB. Total intraoperative time with low CI and normal MAP was 66.5 (56) minutes, representing mean (SD) 69% (23%) of the total time with low CI; 45.8 (38) minutes occurred pre-CPB and 20.6 (27) minutes occurred post-CPB. Overall, the correlation (mean [SD]) between CI and MAP was 0.33 (0.31), and the correlation was significantly higher pre-CPB (0.53 [0.32]) than post-CPB (0.29 [0.28], 95% confidence interval [CI] for difference [0.18-0.34], P < .001); however, there was substantial heterogeneity among participants in correlations of CI with MAP before and after CPB. Secondary analyses that accounted for CVP did not alter the correlation between CI and MAP. Exploratory analyses suggested duration of low CI (C <2 L/min/m2) was associated with increased risk of postoperative acute kidney injury (odds ratios [ORs] = 1.09; 95% CI; 1.01-1.13; P = .018). In a prospective cohort of patients undergoing CAB surgery, low CI was common even when blood pressure was normal. CI and MAP were correlated modestly. Correlation was higher before than after CPB with substantial heterogeneity among individuals. Future studies are needed to examine the independent relation of low CI to postoperative kidney injury and other adverse outcomes related to hypoperfusion.

Research on an Autonomous Localization Method for Trains Based on Pulse Observation in a Tunnel Environment.

China's rail transit system is developing rapidly, but achieving seamless high-precision localization of trains throughout the entire route in closed environments such as tunnels and culverts still faces significant challenges. Traditional localization technologies cannot meet current demands, and the present paper proposes an autonomous localization method for trains based on pulse observation in a tunnel environment. First, the Letts criterion is used to eliminate abnormal gyro data, the CEEMDAN method is employed for signal decomposition, and the decomposed signals are classified using the continuous mean square error and norm method. Noise reduction is performed using forward linear filtering and dynamic threshold filtering, respectively, maximizing the retention of its effective signal components. A SINS/OD integrated localization model is established, and an observation equation is constructed based on velocity matching, resulting in an 18-dimensional complex state space model. Finally, the EM algorithm is used to address Non-Line-Of-Sight and multipath effect errors. The optimized model is then applied in the Kalman filter to better adapt to the system's observation conditions. By dynamically adjusting the noise covariance, the localization system can continue to maintain continuous high-precision position information output in a tunnel environment.

Hybrid integrated GaSb/Si3N4 narrow linewidth (&amp;lt;50 kHz) distributed Bragg reflector laser

A narrow linewidth hybrid integrated distributed Bragg reflector (DBR) laser platform operating at 2 μm wavelength region is demonstrated. The laser architecture comprises AlGaInAsSb/GaSb type-I quantum well reflective semiconductor optical amplifiers butt-coupled to a Si3N4 photonic integrated circuit (PIC), incorporating a narrow-band DBR. The DBR is realized with a long spiral-shaped waveguide structure with periodic circular posts placed adjacent to the waveguide. At room temperature operating conditions, the laser exhibits a maximum continuous wave output power of more than 17 mW for emission near 2 μm. Linewidth properties are analyzed with a heterodyne measurement technique, involving the mixing of the laser signal with a frequency comb phase-locked to an ultra-stable laser. The hybrid laser exhibits a narrow linewidth of ∼8 kHz in 1 ms timescale and ∼50 kHz in 10 ms timescale.

Reliability and benefit of estimated continuous cardiac output measurement using shunt-side SpO2 monitor in hemodialysis.

Estimated continuous cardiac output (esCCO) is a novel technology that enables non-invasive and continuous monitoring of cardiac output. We compared the concordance in accuracies among esCCO measurements in the shunt limb and non-shunt limb. In this single-center prospective observational study, we include Japanese patients who underwent dialysis at our center between April 27, 2021, and February 28, 2023. Clinical accuracy of esCCO was evaluated in the shunted and non-shunted bilateral digits. Agreement between the measurements was analyzed using Lin's congruent correlation and Bland-Altman analysis. For 43 individuals, Lin's concordance correlation coefficient was 0.9887 (95% confidence interval of 0.9886-0.9887) indicating good agreement. The values of esCCO measured in the shunt and non-shunt limbs were compatible. The percentage errors for the 43 patients with arterio-venous fistula (AVF) or arterio-venous graft (AVG), 32 with AVF, and 11 with AVG were 9.3%, 9.3%, and 8.9%, respectively. esCCO could be used in shunt as well as non-shunt limbs during dialysis, allowing continuous and non-invasive hemodynamic monitoring.

Electrification of Agricultural Machinery: One Design Case of a 4 kW Air Compressor

In response to the global pursuit of net-zero carbon emissions, the electrification of agricultural machinery is becoming a significant research and development trend. This study introduces the overall design of a 4 kW air compressor aimed at achieving a green vision for agricultural machinery. The design focuses on providing continuous and stable power and air output using a lithium-ion battery. Durability and cost-effectiveness are prioritized, with a particular emphasis on the Arduino system for integrating battery and motor systems to withstand harsh conditions and ensure ease of maintenance. A permanent magnet brushless motor was selected as the power source, paired with an optimized pulley to supply the proper torque to the air compressor. The system employs an Arduino-based feedback control sensor for air pressure regulation, ensuring energy efficiency. The primary energy source is a 48 V lithium iron phosphate battery, known for its high energy density and safety. The battery design focuses on system integration, addressing specific environmental discharge requirements. The embedded battery management system provides thermal and lifecycle parameter estimation, guaranteeing long-duration power supply and safe operation under various conditions. Unlike traditional fuel-driven systems, lithium iron phosphate batteries do not emit harmful gases, aligning with environmental standards. System integration testing demonstrated that the air pressure feedback control effectively meets the energy-saving requirements by digitally reducing power output as air accumulates in the chamber. Bench testing confirmed that the system performs as designed, achieving the desired results and advancing the goal of sustainable agricultural machinery.

Adaptive Sliding-Mode Controller for a Zeta Converter to Provide High-Frequency Transients in Battery Applications

Hybrid energy storage systems significantly impact the renewable energy sector due to their role in enhancing grid stability and managing its variability. However, implementing these systems requires advanced control strategies to ensure correct operation. This paper presents an algorithm for designing the power and control stages of a hybrid energy storage system formed by a battery, a supercapacitor, and a bidirectional Zeta converter. The control stage involves an adaptive sliding-mode controller co-designed with the power circuit parameters. The design algorithm ensures battery protection against high-frequency transients that reduce lifespan, and provides compatibility with low-cost microcontrollers. Moreover, the continuous output current of the Zeta converter does not introduce current harmonics to the battery, the microgrid, or the load. The proposed solution is validated through an application example using PSIM electrical simulation software (version 2024.0), demonstrating superior performance in comparison with a classical cascade PI structure.

Bioinspired carbon black deposited polyimide fabric for sustainable water energy harvesting

Water is the source of life and the largest energy carrier on Earth. Various excellent hydrovoltaic technologies have been proposed, but still suffer from issues such as intermittent output, material limitations, and poor flexibility. Here, we proposed a method for fabrication of a hydrovoltaic generator using the flexible polyimide fabric. Carbon black was deposited on the polyimide fabric surface using a simple method of candle flame burning. On the basis of water transport in the fabric and charge separation induced by negatively charged carbon black channels, sustainable hydrovoltaic power generation was achieved by the generator. A single carbon deposited polyimide fabric (CBP) could generate a continuous voltage output of nearly 260 mV by dripping a water drop on one side. Multiple CBP devices were connected in series and parallel to increase output power, which could be applied for the power and energy storage of small electronic devices. This work may provide a convenient strategy for fabricating sustainable flexible hydrovoltaic generators and offer insights for the development of clean power sources.