Smooth Output Research Articles

Composite power supply topology design with energy-controlled distribution switches

An electric car’s battery is equivalent to a fuel vehicle’s engine, without a battery, it is equal to an empty shell. The single energy supply of the battery is difficult to meet the long-term endurance requirements of electric vehicles. Combined with the existing traditional composite power structure, the advantages and disadvantages of the existing traditional composite power supply structure are analyzed. A composite power supply structure combining a supercapacitor and power battery is proposed. The supercapacitor is responsible for the peak high power output, and the power battery is responsible for smooth power output. Simulation results show that the new composite power supply has noticeable improvements compared to traditional structures regarding energy loss and power distribution.

Fault Diagnosis of Hydraulic System based on SOM Neural Network

The working principle of hydraulic system is to use the flow and pressure of liquid in the system for energy transfer and conversion. Hydraulic system realizes various work tasks such as pushing, grasping, lifting, rotating, etc. by controlling the action of hydraulic actuators. Its advantages are high power density, good stability, fast response time, smooth power output, etc. The disadvantage is that the hydraulic system is easy to lose control of more points. In this paper, taking the horizontal outrigger hydraulic circuit as an example, the hydraulic pump leakage, etc. is used as a fault sample, and the SOM neural network is used for fault diagnosis to make timely and accurate diagnosis of the abnormal or fault state of the hydraulic system, give guidance on the operation of the hydraulic system, improve the reliability and safety of operation, and reduce the fault loss to a minimum.

Design, development, fabrication and evaluation of the dynamics of a graphene based underwater acoustic vector sensor: A simulation and experimental study

In the last decade, the usage of underwater vector sensor has gained a lot of importance in the detection of low frequency underwater acoustic signals, as the noise level radiated by the submarine has been drastically reduced. Acoustic sensor based on Micro Electro Mechanical Systems (MEMS) technology is the recent advancement in the area of underwater acoustic vector sensors. We are reporting the design, fabrication, preliminary characterization and evaluation of the dynamics of a two-dimensional underwater acoustic vector sensor by simulation and experimental study. The vector sensor is realized using Reduced Graphene Oxide (rGO) as sensing element and Kapton as flexible substrate, to yield better sensitivity compared to the conventional acoustic vector sensor. Design of vector sensor is inspired by the biological sensing system of fish. The application of piezoresistive transduction principle and MEMS technology helps in miniaturisation and low frequency acoustic signal detection. The fabrication process is made simple, scalable and cost minimum by using the method of drop casting for the deposition of rGO on flexible substrate kapton, thereby eliminating the requirement of clean room. COMSOL Multiphysics 5.5 version is used to simulate acoustic vector sensors using polysilicon and rGO on substrates, silicon and flexible kapton respectively. The simulation results indicate that the sensitivity of rGO based acoustic vector sensor is −149.47 dB which is better in comparison with the sensitivity of −173.37 dB of conventional polysilicon vector sensor. By simulation, the natural frequency of the sensor is found to be 46.62 Hz, which closely matches with the theoretical value 41.06 Hz of the device as per the design criteria and hence, it could detect the low frequency acoustic signals. The displacement sensitivity of the fabricated sensor is found to be 0.0264 V/mm and 0.0276 V/mm for applied displacements in axial and radial directions respectively. The device is tested for its performance parameters i.e., sensitivity and directivity, by performing an acoustic test in the presence of an elastic medium, water. This test results infer that, the device is able to detect and give smooth output response for the acoustic signals in the low frequency range. The Y and X-channel receiving sensitivity exhibited by the sensor is found to be −128.04 dB to −134.93 dB and −130.61 dB to −136.78 dB respectively. Directivity pattern of the sensor is found to be in the shape of 8 with symmetry. As the device is a vector sensor, in addition to the scalar pressure measurement, it should be able to provide additional incentives such as acoustic particle displacement and acoustic particle velocity at any point in the acoustic field. In this paper, an experimental setup is made to generate deep and intermediate water waves, thereby attempting to simulate ocean conditions in the laboratory. Subsequently the numerical evaluation of the wave kinematics, i.e., fluid particle displacement and fluid particle velocity are performed by applying Airy's theory. An effort is also made to analyse the wave kinematics for various water depths, varying from Surface Water Level (SWL) till the sea bed. In this study, wave kinematics are analysed numerically by using experimental data and also by modelling Fluid-Structure Interactions in COMSOL Multiphysics environment. Our results show that the fluid flow of velocity 0.31 m/s results in fluid particle velocity of 0.125 m/s at time 0.215 s (around f = 5 Hz) by both the methods and fluid particle displacement is found to be 19.66 μm. The experimental test setup and videos are made publicly available1: 1https://sites.google.com/view/smithapaib/downloads

Spatial Azimuthal Misalignment Characteristics of High-Temperature Superconducting Wireless Power Transmission Systems

Magnetically coupled resonant wireless power transmission technology (WPT) based on high-temperature superconducting (HTS) coils has gained wide popularity due to its low impedance and high-quality factor Q value characteristics. This technology has greatly improved the energy transfer performance of wireless power transmission (WPT) systems. However, practical applications of conventional WPT, such as wireless charging of autonomous underwater vehicles at mooring points, often encounter spatial misalignment issues due to the complex ocean environment and ocean currents. Nonetheless, few studies have investigated the spatial misalignment of HTS WPT systems, particularly the angular misalignment. This paper presents a solution to address this problem by constructing magnetically coupled resonant wireless energy transmission systems based on HTS coils and copper coils. The study analyzes the relationship between the transmission efficiency of the WPT system and the received power of the load with respect to the spatial orientation of the coil. The performance of the superconducting coil and copper coil WPT systems is compared. The experimental results demonstrate that, under the same spatially misaligned conditions, the WPT system using HTS coils can significantly improve the transmission efficiency and load power compared to the conventional copper WPT system. Moreover, simultaneous adjustment of the lateral misalignment distance and different orientation deflection angles can improve the transmission efficiency and smooth load output power of the high-temperature superconducting WPT system.

Surrogate analytical models of damage localization in metal matrix composites

Several parameters entering the constitutive laws of metal matrix composites are not amenable to direct measurement. Their determination is therefore demanded to indirect identification procedures, based on the comparison between the output of some experimental works and the results of the iterative simulation of the performed tests. Largely repetitive numerical analyses can also support the optimized design of composite microstructures, the understanding of the actual stress-transfer mechanisms, and virtual testing. Surrogate analytical models can replace effectively non-linear finite element (FE) computations in parametric studies and identification procedures, reducing execution times and costs without compromising the accuracy of the results. In this context, a frequently used approach consists of the interpolation, by means of radial basis functions (RBFs), of data filtered by proper orthogonal decomposition (POD). This methodology is often used to reproduce the smooth output of different mechanical systems. This work is rather focused on the homogenized response of damaging metal matrix composites subjected to strain localization phenomena, and explores the accuracy achievable in these situations by the POD-RBF approximation of more traditional FE analyses. In all considered cases, the POD-RBF results are accurate, and able to distinguish between apparently similar situations. The approach is flexible, and the performance of the surrogate models can be tailored to the requirements of each application. In particular, various analytical approximations can be introduced to support the design of new microstructures and material couplings, and to understand the role of any material and/or geometry imperfections resulting from the production processes.

Modeling and Controller Design of a Hybrid Input-Parallel Output-Serial Modular DC-DC Converter for High Efficiency and Wide Output Range

Modular input-parallel output-serial (IPOS) DC-DC converter is becoming a crucial solution for high-voltage applications due to its flexible combination form without switching device pressure limitation. It requires high efficiency, fast response, and wide-range output for broader applications. However, the existing solutions cannot simultaneously meet all these requirements. This paper proposes a new hybrid structure with interleaved LLC converters and a DAB converter. The interleaved LLC converters provide the most output voltage with fixed switching frequency and duty cycle, while the DAB converter regulates the output voltage. The wide range output is achieved by switching the LLC converter module and continuously adjusting the output voltage of the DAB converter. Furthermore, a switching control method based on the sliding-mode variable structure is proposed to achieve a smooth and fast output voltage response during the switching process. Finally, a 0.3/0.9-1.8kV, 2kW experimental platform is established to verify the proposed converter's effectiveness and advantages.

Implementation and Applications of Grid-Forming Inverter with SiC for Power Grid Conditioning

Sustainable energy technologies have become promising solutions to global warming and climate change. Operation of the electric power grid has been dominated in the past by synchronous generation, wherein conventional sustainable energy inverters are designed simply to feed maximum real power into the grid. With the increasing penetration of renewable energy, it is undergoing a rapid shift toward the power generation of inverter-based resources (IBRs). As a result, transitioning to a power grid with more IBRs requires introducing advanced inverter technology that can respond to various disturbances in frequency and voltage occurring on the grid. The grid-forming (GFM) inverter equipped with an energy storage system featuring frequency and voltage support functionalities is vital for the stability of the micro power grid system. The GFM inverter also offers PV output smoothing, low voltage ride through, and low frequency ride through. In addition, the GFM inverter functions as a voltage source inverter to supply energy under off-grid state when the main grid is in fault conditions. A SiC-based 30 kVA GFM inverter is presented with a 3-phase 3-level neutral-point-clamped (NPC) topology for high-frequency operation to achieve high efficiency and power density. Designchallenges in gate driver design, PCB layout, and thermal consideration are addressed. The performances of the designated GFMinverter are measured and tested under on-grid and off-grid operations to verify the functionalities of the advanced inverter, as well.

Cooperative Guidance Law for the Mother-Cabin of the Anti-UAV Cluster Mother-Son Missile

This article investigates a novel operational pattern for intercepting UAV clusters over the range of middle and far distances using mother-son missiles. To address the guidance issue of the mother-cabin in the operational pattern, a special cooperative guidance law, which takes into account acceleration constraint and satisfies the constraints of impact time, speed, and zero line of sight angle (LOS), is proposed. Based on consistency theory and sliding mode control theory, the proposed cooperative guidance law is specifically designed for the mother-cabin of the mother-son missile. This approach offers several advantages, including a simple structure and smooth controller output, and smooth flight trajectory. Finally, numerical simulations are presented to demonstrate the effectiveness and applicability of the cooperative guidance law.

Iterative histogram equalization using discrete wavelet transform in low-dynamic range

A progressive histogram equalization (HE) and contrast enhancement method is proposed in the frequency domain. This method has an iterative structure based on the 6-sigma rule in the low-dynamic range using discrete wavelet transform. The proposed method determines an automatic threshold for attenuating the high-frequency amplitude of a signal in the discrete wavelet domain, based on the standard deviation of the absolute power of the high-frequency components in the signal band generated from the probability density function (PDF). Then an iterative quantization procedure is used where the PDF values in the frequency domain are randomly quantized. Besides, the maximum Bhattacharyya coefficient, which matches the original input image’s PDF, is used as a cost function to optimize the histogram smoothing output. For the random number generation, a 32-bit pseudorandom generator is employed to produce the same result for the output image at each runtime. The quantization factor parameter enables a controlled contrast enhancement rate to receive balanced equalization results in images. In the experimental studies, the proposed iterative HE method is compared with the well-known global, local, and brightness preserving algorithms. Experimental studies quantitatively and qualitatively display promising and encouraging results in terms of various state-of-the-art quality assessment metrics such as mean squared error, peak signal-to-noise ratio, structural similarity index measurement, contrast improvement index, absolute mean brightness error, and quality-aware relative contrast measure.

A WGAN-GP-Based Scenarios Generation Method for Wind and Solar Power Complementary Study

The issue of renewable energy curtailment poses a crucial challenge to its effective utilization. To address this challenge, mitigating the impact of the intermittency and volatility of wind and solar energy is essential. In this context, this paper employs scenario analysis to examine the complementary features of wind and solar hybrid systems. Firstly, the study defines two types of complementary indicators that distinguish between output smoothing and source-load matching. Secondly, a novel method for generating wind and solar output scenarios based on improved Generative Adversarial Networks is presented and compared against the conventional Monte Carlo and Copula function methods. Lastly, the generated wind and solar scenarios are employed to furnish complementary features. The testing results across eight regions indicate the proposed scenario generation method proficiently depicts the historical relevance as well as future uncertainties. This study found that compared to the Copula function method, the root mean square error of the generated data was reduced by 4% and 3.4% for independent and hybrid systems, respectively. Moreover, combining these two resources in most regions showed that the total output smoothness and source-load matching level cannot be enhanced simultaneously. This research will serve as a valuable point of reference for planning and optimizing hybrid systems in China.

Fabrication of Battery-Operated Roof Paint Sprayer with Automatic Charging Off System

The study was conducted at Barangay San Juan, Aborlan, Palawan, and was evaluated from April to December 2021. Fabrication of the device was based on the needs of roof painters to lessen their exposure to sunlight during roof painting. The roof paint sprayer was divided into three major parts. First, the container served as overall part with hand carry at the top, which weighs 6 kilograms when empty but approximately 11 kilograms when full. Second, the direct current motor is rated 60 W, 12 V nominal, maximum flow of 5 liters per minute, and a maximum pressure of 116 psi. The base of the motor was fitted at the bottom while the hole of the first container is connected to the inflow of the motor, and a hose with an adjustable nozzle is connected to the outflow. Third, the power source consisted of a connector cord, female socket, 12V transformer, circuit board, green LED, 12Vdc battery, battery indicator, and switch. The performance evaluation of the device revealed during testing showed that at the start the roof paint sprayer works smoothly and sprayed almost 1/3 area of the target area (10×3 meters) for almost 2 minutes but suddenly as it sprayed, the dc motor starts difficult to run until it stopped. The major benefit of the device, if studied further, will spray faster on roofs and smooth output.

Flywheel energy storage controlled by model predictive control to achieve smooth short-term high-frequency wind power

The use of energy storage systems to improve the fluctuation of wind power generation has garnered significant in the development of wind power. However, the fluctuation of the signals in the high-frequency part of the wind turbine output is particularly drastic and short in duration. As a kind of physical energy storage device, the flywheel energy storage device has a fast response speed but higher requirements on the control system. In order to improve the control effect of the flywheel energy storage device, the model predictive control algorithm is improved in this paper. First, the high-frequency components of the wind farm output power data are extracted by the wavelet packet decomposition algorithm, and the high-frequency components are optimized by mathematical interpolation as the data basis. Secondly, a mathematical model of the flywheel energy storage system applied in the model predictive control algorithm is proposed, and the model predictive control algorithm is used to configure the flywheel energy storage device to achieve a smooth output power of the wind farm. Finally, the simulation is performed in MATLAB and the experimental parameters are adjusted. The experimental results show that the configuration of the flywheel energy storage system based on the model predictive control algorithm can effectively smooth the fluctuation of the high-frequency component of the output power data of the wind farm. The experimental results take the wind power data of different time periods for energy storage configuration, and the comparison verifies the reliability of the system designed in this paper.

Parallel Water Column Technique for Obtaining a Smooth Output Power of the Pump as a Turbine at a Variable Water Flow Rate

Hydro generation is the simplest and oldest method of electricity generation, with a century of successful operation. Using a pump as a turbine (PAT) is an optimal solution for minimizing the cost, particularly in low-head and small-scale hydro plants. Commercially available centrifugal pumps have become a popular solution for small-scale hydro and pumped-hydro facilities owing to their simple geometry, ease of operation, maintenance, and abundant availability in local markets. Variations in the water flow in hydro facilities, such as pumped-hydro and small-scale hydro facilities, are common; however, a PAT is unable to respond to variable flows because it is a fixed-speed device. To overcome this problem, different techniques have been suggested by researchers: (a) a system of parallel PATs; (b) geometrical modifications in the impeller of the PAT; and (c) power electronics-based variable frequency drives. All the aforementioned techniques have limitations, such as low output, high cost, complexity, transportation, and operation and maintenance. In this study, a simple and economical technique is proposed to smooth the output of a PAT on variable/decreasing water flow profiles. In the proposed technique, water columns connected in parallel (PWCs) are used to produce a pressurized water flow, as they have a convergent nozzle at the outlet. The PWC creates more space for water, and this additional mass of water boosts the water flow at the outlet. In this manner, the PWC technique maintains the flow at the inlet of the turbine. A serial integration of five PWCs with the same dimensions was conducted to inject the additional flow into the existing PAT penstock, governing a 37-kW generator. The design flow was maintained at 192.1 L/s without any additional power usage at the inlet of the PAT, and the output was smoothed even at the minimum water flow/head. Pump design and computational fluid dynamics simulations were performed using ANSYS software, whereas generator simulations were performed using MATLAB/Simulink software.

Reliability Evaluation of Remote Wind-storage Plant Based on Substitutable Output Capacity

Energy storage is widely introduced and integrated into generating systems involving renewable energy usage, as it can smooth power output, alleviate system volatility, and reduce renewable power spillage. This paper studies the reliability evaluation of remote wind-storage plants. The dispatch procedure is formulated to supply smooth power output during a long-time horizon. The concept of substitutable output capacity is introduced to evaluate the capability of a wind-storage plant that provides steady power during most time segments. The proposed model can provide meaningful inference on the reliability and stationarity of a renewable plant, reflecting the advantage of storage-assisted generation.

A Water Tank Level Control System with Time Lag Using CGSA and Nonlinear Switch Decoration

Tank level control has some unavoidable factors such as disturbance, non-linearity, and time lag. This paper proposes a simple and robust control scheme with nice energy-saving effects and smooth output to improve the quality of the controller and meet real-world application requirements. A linear controller is first designed using a third-order closed-loop gain-shaping algorithm. We then use an arcsine function to modify the system with non-linear switching to reduce the effect of the non-linear modification on the dynamic performance of the control system. Furthermore, we use the Nyquist stability criterion to demonstrate the stability of the closed-loop system in the presence of time lag. The results of the final simulation experiment show that the controller not only has high control quality but also has the characteristics of energy saving and smooth output under the condition of lag and pump performance constraints. These features are necessary for extending the life of the pump and enhancing the applicability of the tank level controller.

A switching control method based on a new model considering parasitic capacitance for LLC

LLC converters are used for linking renewable energy and smart grids. However, the output is higher than the reference caused by its own characteristics, especially in the light load, and the output is limited. A new control method is proposed in this paper based on a new model considering parasitic capacitance, which plays a vital role in keeping the output constant in the light load conditions and widening the output range. In addition, the definition of the light load is given in this paper, which ensures an accurate control. In the switching process, a transition period is set to avoid the components from being damaged due to sudden switching and ensures a smooth output and the stability of the control. Finally, this control method based on the new model is proved valid on a 400 V-36 V-1 kw prototype.

A novel approach to design of a power factor correction and total harmonic distortion reduction-based BLDC motor drive

This study describes a novel approach to design of a power factor correction (PFC) and total harmonic distortion (THD) reduction-based brushless DC (BLDC) motor drive. The drive was designed to obtain a reduced THD for PFC. The basic design of the BLDC motor drive contains an AC voltage source as input for a diode bridge rectifier. The output DC voltage is filtered out to reduce ripples. The smooth DC output voltage is supplied to the modified Zeta converter. The output voltage of the modified Zeta converter is controlled by using pulse width modulation (PWM). The modified Zeta converter is utilized in discontinuous inductor current mode (DICM) for better power factor. This controlled DC voltage is supplied to the voltage source inverter (VSI) as input. The VSI is designed to convert input DC into a suitable AC voltage source. The output voltage of the VSI depends upon switching patterns applied to power transistors generated by space vector PWM. Additionally, the output of the VSI is supplied to the BLDC motor for speed control. The main purpose of this paper is to simulate and assess BLDC motor function via the MATLAB/Simulink environment, using SimPowerSystems and the Simscape toolbox, with the goals of improved power factor, lower THD, and better speed control. The PFC modified Zeta converter topology produced the best power factor, currently 0.981, which is better than other topologies, with a THD of only 9.81%, the lowest of all three topologies, which demonstrates the significance of the proposed model.

Design of high voltage gain converter for fuel cell based EV application with hybrid optimization MPPT controller

From the previously available articles, the fuel cell dependent power supply systems are increasing every year. Also, these systems are playing a major focus on the microgrid renewable energy networks. However, the fuel cell gives less output power extraction at different operating temperature values. In addition, the working point of the fuel cell vary with respect to the hydrogen supply, and water membrane content. In order to achieve the high output power of the fuel stack, a Maximum Power Point Tracking (MPPT) is used to track the peak power point of the proposed system. In this article, Artificial Neuro Fuzzy Inference System (ANFIS) controller is utilized in order to generate the smooth output voltage waveform of the fuel cell stack. The optimization of ANFIS controller have been done by using the Genetic Algorithm (GA). The advantages of ANFIS based MPPT controller are high output power extraction, and less distortions of converter voltages. Here, the Proton Exchange Membrane Fuel Cell (PEMFC) device is used as a source. The features of PEMFC are fast start-up, and high efficient. The PEMFC generates less voltage which is enhanced by using the interleaved non-isolated boost converter. The proposed fuel cell based interleaved system is analyzed by using the MATLAB/Simulink software.

Analisa Variasi Saringan Mesin Penggiling Daging Ayam Kapasitas 1 Kg Terhadap Waktu

Bakso is a type of chicken meat ball that is commonly found in Indonesian cuisine. Currently, chicken meatballs are one of the processed chicken meat products that have a particular taste. The biggest energy contribution comes from protein, which reaches 60 percent, followed by fat as much as 38% and carbohydrates as much as 2%. The high public demand for processed products such as chicken meatballs has resulted in most shops, from stalls, school canteens, grocery stores, to supermarkets selling chicken meatballs. Before the existence of modern meat grinding machines, the process of grinding chicken meat was very difficult, but now, with advances in technology, there are many grinding machines on the market that simplify the process of grinding meat. The business of making and selling chicken meatballs has attracted the interest of several community business groups with small and medium scale businesses. In order for the business of producing and selling chicken to meet public demand both in terms of quantity and in terms of quality, good planning and management is needed. The design method used includes grinding machine product design. The result of the design that has been done is the output diameter of the meat with a size of 5 mm with the appropriate results (fine on average). Where the diameter of 2 mm and 3 mm produces chicken meat that comes out very slowly and is very smooth and causes the meat to melt and the chicken meat comes out fast and smooth. Thus, it can be concluded that a chicken meat grinder machine can grind 1 kg of chicken meat in 1 minute and the appropriate output hole size is 5 mm with a smooth and fast output of chicken meat.

Analysis and Fault-Tolerant Control for Dual-Three-Phase PMSM Based on Virtual Healthy Model

Dual-three-phase permanent magnet synchronous machines (DTP-PMSMs) are famous for their fault-tolerant capability. However, the complex modeling, high copper loss, and torque ripple under postfault operation limit their further application. In this article, a fault-tolerant control (FTC) strategy is developed for DTP-PMSMs under the open-phase fault (OPF) with straightforward modeling and smooth output torque. The virtual healthy DTP-PMSM model, where the coordinate transformation, the modulation strategy, and the controller structure remain unchanged under OPF, is adopted in the proposed FTC scheme. And the current references are derived in sinusoidal waves with minimum copper loss. The inaccurate transmission of control signals under OPF is also focused on. Comprehensive theoretical analysis shows the relationship between the controller output voltage and the actual stator voltage should be considered in the proposed FTC strategy; otherwise, distortion in torque and current will be introduced. The voltage compensation is utilized to compensate for the voltage difference and ensure the smooth torque output. Besides, a quasi proportional resonance controller is designed to further suppress the residual torque ripple. The proposed strategy will not induce complex implementation and heavy computation burden. The simulation and experimental results prove the analysis and the effectiveness of the proposed strategy.