Electric Plants Research Articles

A remote sensing approach for exploring the dynamics of jellyfish, relative to the water current

Drifting in large numbers, jellyfish often interfere in the operation of nearshore electrical plants, cause disturbances to marine recreational activity, encroach upon local fish populations, and impact food webs. Understanding the dynamic mechanisms behind jellyfish behavior is of importance in order to create migration models. In this work, we focus on the small-scale dynamics of jellyfish and offer a novel method to accurately track the trajectory of individual jellyfish with respect to the water current. The existing approaches for similar tasks usually involve a surface float tied to the jellyfish for location reference. This operation may induce drag on the jellyfish, thereby affecting its motion. Instead, we propose to attach an acoustic tag to the jellyfish’s bell and then track its geographical location using acoustic beacons, which detect the tag’s emissions, decode its ID and depth, and calculate the tag’s position via time-difference-of-arrival acoustic localization. To observe the jellyfish’s motion relative to the water current, we use a submerged floater that is deployed together with the released tagged jellyfish. Being Lagrangian on the horizontal plane while maintaining an on-demand depth, the floater drifts with the water current; thus, its trajectory serves as a reference for the current’s velocity field. Using an acoustic modem and a hydrophone mounted to the floater, the operator from the deploying boat remotely changes the depth of the floater on-the-fly, to align it with that of the tagged jellyfish (as reported by the jellyfish’s acoustic tag), thereby serving as a reference for the jellyfish’s 3D motion with respect to the water current. We performed a proof-of-concept to demonstrate our approach over three jellyfish caught and tagged in Haifa Bay, and three corresponding floaters. The results present different dynamics for the three jellyfish, and show how they can move with, and even against, the water current.

STUDY OF THE PERFORMANCE OF THE DYNAMIC LEVEL STABILIZATION SYSTEM OPERATION IN THE WELLBORE EQUIPPED WITH AN ELECTRICAL SUBMERSIBLE PUMP UNIT

Link for citation: Totanov A.S., Molchanova V.A., Urazakov K.R. Study of the performance of the dynamic level stabilization system operation in the wellbore equipped with an electrical submersible pump unit. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 8, рр. 210-219. In Rus. The relevance of the study is related to the widespread use of electrical submersible pump units in the production of low-viscosity oils and water-gas-oil emulsions at this stage of development of mechanized production. However, the current production conditions associated with changing reservoir parameters bring to the fore a number of technical problems that need to be solved. One of these challenges is the phenomenon in which the dynamic level of the well decreases due to changes in reservoir parameters (reservoir pressure, productivity factor, etc.). Decrease of dynamic liquid level in the well leads to complications during operation of electrical submersible pump units. As a consequence, the increased cavitation in impellers is possible due to pressure reduction on the pump intake, and also full pump supply failure is not excluded at significant reduction of the dynamic level of the borehole fluid. In this relation, a technical solution, consisting in installation of bypass device (electrical valve) above the place of suspension of electrical submersible pump plant to maintain stable dynamic liquid level in the well and avoid complications during pump operation, was suggested. To confirm the feasibility of the dynamic level stabilization system, a mathematical model was developed to evaluate the effectiveness of complication prevention with the help of the proposed technical solution during the operation of the electric centrifugal pump unit. The main aim of the research is to develop a calculation method for studying the dynamics of the dynamic level stabilization system. Objects: an electrical submersible pump unit in conjunction with a system for stabilizing the dynamic level of the well. The influence of the diameter and length of the electrical valve on the efficiency of the dynamic level recovery was studied, taking into account hydraulic losses during the system operation. Methods. The research method is reduced to numerical solution of differential, linear and non-linear equations describing flow and pressure at electrical submersible pump unit outlet in steady-state mode, fluid flow through the electrical valve taking into account hydraulic resistances, flow of hydrodynamic processes in annular space during stabilization system operation, that is change of fluid level above the pump depending on borehole conditions and design parameters of electric valve. Results. Effect of parameters of the bypass valve – the diameter of flow section and length on dynamics of change of a liquid level above the pump, as well as the impact of liquid properties, namely its viscosity on intensity of restoration of a liquid level above the pump was studied. It was found that when the diameter of the electrical valve is increased, more intensive restoration of the liquid level above the pump is observed due to the reduction of hydraulic resistance in the valve cavity. Similarly, it was found that with increase of electrical valve length, as well as with increase of viscosity of liquid, coefficient of flow and intensity of liquid level recovery above the pump decreases respectively.

A Turkish Mayor Goes to Moscow: Vedat Dalokay and Development Politics in the 1970s

In 1975, the mayor of Ankara requested Soviet assistance to build a public transportation system and affordable housing in the Turkish capital. This article uses Vedat Dalokay's appeal as a window into international development politics during a transformative decade. The 1970s saw growing leftism in Turkey, and Dalokay hoped that progressive urban planning would solidify voting trends among rural-to-urban migrants. He sought to introduce a new ideological element into Soviet–Turkish exchange, but politicians and academics in Moscow dismissed Dalokay's class-oriented projects. Instead, they increased their investments in the steel mills and electricity plants that were hallmarks of Soviet economic exchanges with the Third World. Whereas Dalokay's aspirations emerged from a Turkish intellectual climate that was being reshaped by dependency theory and by disillusionment in the possibilities for growth within boundaries defined by the political borders of nation-states, Soviet economists and bureaucrats remained wedded to the idea of development defined in terms of the territorial economy. The Ankara municipality eventually turned to Western Europe, but the Turkish government continued to negotiate gas pipelines and nuclear power plants with the Soviet and post-Soviet Russian governments. This article explores the ideological assumptions that have shaped economic exchange across the Black Sea.

Relationships among apparent electrical conductivity and plant and terrain data in an agroforestry system in the Ozark Highlands

AbstractMinimal research has been conducted relating apparent electrical conductivity (ECa) surveys to plant and terrain properties in agroforestry systems. Objectives were to identify: (i) ECa–forage yield, –tree growth, and –terrain attribute relationships within ECa‐derived soil management zones (SMZs) and (ii) terrain attributes that drive ECa variability within a 20‐year‐old, 4.25‐ha, agroforestry system in the Ozark Highlands of northwest Arkansas. The average of 12 monthly perpendicular (PRP) and horizontal coplanar (HCP) ECa surveys (August 2020 to July 2021) and 14 terrain attributes were obtained. Tree diameter at breast height (DBH) and height (TH) measurements were made in December 2020 and March 2021, respectively, and forage yield samples were collected during Summer 2018 and 2019. Apparent EC‐tree property relationships were generally stronger within the whole site (averaged across tree property and ECa configuration, |r| = 0.38) than within the SMZs (averaged across tree property, ECa configuration, and SMZ, |r| = 0.27). The strength of the SMZs’ terrain‐attribute‐PRP‐ECa relationships were 9% to 205% greater than that for the whole site. In whole‐site, multi‐linear regressions, slope length and steepness factor (10.5%), mid‐slope (9.4%), and valley depth (7.2%) had the greatest influence (i.e., percent of total sum of squares) on PRP ECa variability, whereas valley depth (15.3%), wetness index (11.9%), and mid‐slope (11.2%) had the greatest influence on HCP ECa variability. Results show how ECa relates to plant (i.e., DBH, TH, and forage yield) and terrain data within SMZs in agroforestry systems with varying topography and could be used to precisely manage agroforestry systems.

Techno-economic optimization of hybrid-electric power plants onboard cruise ships

This work aims at assessing energy, environmental and economic performances of hybrid-electric plants installed onboard large-size cruise vessels fuelled by Liquefied Natural Gas. Specifically, hybrid-electric power plants coupling combined gas electric and steam plants, reciprocating engines and lithium-ion battery pack are considered. By adopting cogeneration efficiency, carbon dioxide emissions, nitrogen oxide emissions and costs as objective functions, optimal performances were assessed by a Mixed Integer Linear Programming code, following a two-step procedure. First, the MILP code has been applied considering 8-days long, phase-mean operating profiles to identify an optimal design of the engine room. Second, power plant performances have been investigated by applying MILP code to hourly demand profiles, in order to provide more detailed insight on working schedule. Overall, as main outcome of the phase-mean analysis, the potential of combined gas electric and steam plants and lithium-ion batteries in promoting a more efficient energy utilization, reduced environmental impact and enhanced cost savings is proved. Specifically, combined gas electric and steam plant was shown to optimize objective functions during navigation and maneuvering, whereas batteries improved energy and environmental performances in the most demanding ship operating conditions. Furthermore, optimal sizing of lithium-ion battery pack was determined at 40 MWh, despite its economic competitiveness resulted to deeply rely on carbon tax. On the other hand, the hourly analysis showed that controlling the combined gas electric and steam plant and batteries according to a mixed spinning reserve-peak shaving strategy optimizes the performance of power plant even in port conditions, with almost no role played by reciprocating engines. In detail, in comparison to a reference non-hybrid electric power plant, batteries are shown to improve cogeneration efficiency and greenhouse gas emission savings by nearly 2%, whereas nitrogen oxide emissions and costs were reduced by 12% and 2%, respectively.

Integrating Cyber Resilience Strategies for OT Data Acquisition Devices

Operational Technology (OT), Industrial Control Systems (ICS), and Supervisory Control and Data Acquisition (SCADA) devices have been around in some form since the 1960s and they control specific functions in many critical industries such as electrical power generation, oil refineries, and water treatment plants. Since most are integrated with IT-based protocols (e.g., TCP/IP), there has been an explosion of OT control systems to provide meaningful information to businesses. While OT and IT speak a common language, this has exposed OT to much more Cyber Attacks that were once applied only to IT-based systems. Data Acquisition Devices (DAS), such as those manufactured by Moxa, now have ethernet ports to provide this link between both networks. The combination of new ethernet-capable OT devices, and those using upgraded converters (e.g., Moxa) for older OT devices, has primarily increased the attack surface. This study proposes a secure layered architecture that can be deployed to limit security threats for ethernet-capable (DAS) devices. The current state of many organizations is the lack of visibility of their OT assets and a knowledge gap on how to secure them. Keywords—Control systems, Cyber attacks, Cybersecurity resilience, Operational technology

Automatic Water Level and Pressure Control System Prototype Design Using Programmable Logic Controller and Human Machine Interface

Water level control and pressure control are implemented in many at several industrial processing such as water dam, petrochemical processing plant, pharmacy and food processing plant, overhead tank, waste processing plant, electricity plant, etc. This study analyses a simulation and a needed components for automatically water level control system implementation using programmable logic controller (PLC). The water level control using PLC is designed to control the water level and prevent waste the water from a water tank. PLC is one of devices of automated controller which mostly used. Use of PLCs in industries are indispensable to control parameters which required high precision. In this research studies water level control system using PLC as primary controller and human machine interface (HMI) as remote controller that could visualize state of a system work (plant) in real time on computer screen and could gather field data as well. Main device for this research is Omron PLC CP2E type and touchscreen HMI Omron. At the prototype is used a water tank and a water container (to be one with the water resource), and in the HMI is showed the pages of home, control panel, and plant. From the result of the diagram ladder and the HMI design are got the system run well. The application from this research could be learning media in the system control laboratory for the subject of industrial control system and the others, related to it.

Optimisation and techno-economic assessment of parabolic trough collector system in Malaysia, China, and the United States

We evaluated the economic feasibility of installing PTC plants in several sites in Malaysia, China, and the United States with high solar irradiation or solar power plants. The average values of LCOE, NPV and CF for PTC power plants installed in the United States under optimum conditions are 11.92 USD cents/kWh, 47.95 million USD and 75.40%. Meanwhile, Labuan and Coara in Malaysia are two sites that are ideal for the installation of PTC plants, while Datong in China is the most favourable location for the installation of PTC power plants among the locations evaluated. Therefore, an equation relating the DNI to the optimum LCOE can be established, which recommends installing the PTC power plant in locations with DNI higher than 5.98 kWh/m2/day to replace the coal-fired electricity plant. Abbreviations: Avg: Average; Ch: China; Com: Commercial; CPV: Concentrated Solar Photovoltaic; CSP: Concentrated Solar Power; EES: Engineering Equations Solver; EIA: Energy Information Administration; HTF: Heat Transfer Fluid; IEA: International Energy Agency; Ind: India; IRENA: International Renewable Energy Agency; LFR: Linear Fresnel Reflector; Lit Rev: Literature Review; M salt: A Quinary Salt mixture doped with Hybrid; Graphene/TiO2 Nanoparticles; Mal: Malaysia; PPA: Power Purchase Agreement; PTC: Parabolic Trough Collector; PV: Photovoltaic; Res: Residential; SAM: System Advisor Model; SDG: Sustainable Development Goal; SM: Solar Multiple; SPD: Solar Parabolic Dish; SPT: Solar Power Tower; STE: Solar Thermal Energy; TES: Thermal Energy Storage; UN: United Nations; US: United States

Dynamic performance simulation of combined gas electric and steam power plants for cruise-ferry ships

This work aims at investigating the feasibility of COmbined Gas Electric and Steam (COGES) plants onboard Liquefied Natural Gas (LNG) fueled ships, by means of a novel, flexible tool. Firstly, the nominal operating conditions of 6 commercially available gas turbines (GTs) as well as their dynamic performance are simulated. Secondly, 6 different integrated COGES-reciprocating engine power plants are assembled and compared in terms of cogeneration efficiency within an optimized repowering study for the cruise-ferry ship GNV La Suprema. The optimization accounts for variable ship speed, season and GT control strategy for an overall number of 264 operating conditions considered. Thirdly, the time-dependent performance of the best COGES plant is assessed under actual navigation conditions for La Suprema. Overall, the results show the great potential of combining COGES plants with reciprocating engines for the marine sector. In particular, in the ship speed range centered around the actual cruise speed for La Suprema (i.e. 22 knots), all the COGES plants are able to cover the propulsion and hotel power demands more efficiently than reciprocating engines, with a 1–5 % benefit on cogeneration efficiency. Overall, a 51 % maximum cogeneration efficiency is found to be provided by COGES plants based on LM2500 and TITAN250 gas turbines.

Spillover benefits of carbon dioxide cap and trade: Evidence from the Toxics Release Inventory

AbstractReducing greenhouse gas emissions is necessary to meet climate goals, but these emissions are not the only harmful bi‐products of fossil‐fuel combustion. This paper shows how a regional cap‐and‐trade program designed to regulate CO2 emissions affects the release of federally‐regulated toxins in the Toxics Release Inventory. We find that the program reduces toxic releases from coal‐fired electric plants by 78%, and that harmful metal releases (e.g., lead, mercury) have fallen by 54%. There is no evidence of spillovers into non‐adopting areas. This unintended beneficial effect of the carbon dioxide cap‐and‐trade policy provides compelling evidence of the co‐abatement of harmful compounds alongside greenhouse gas emissions.

A cooperation approach for nexus among biofuel, compost, and water in waste supply chain under risk aversion: A case study

Waste mismanagement has caused environmental pollution, while there is an opportunity to reduce this environmental degradation by converting waste into value-added products. These value-added products from waste have mutual effects from the perspective of water-energy-waste-carbon nexus and a cooperation approach could lead to better management. We develop a Stackelberg game model, where the municipality as a leader intervenes in the waste supply chain with penalties and subsidies to control environmental pollution, water consumption, and energy consumption. The collector collects waste from two channels municipal waste bins and waste purchasing. Buyable waste and recyclable waste from bins are sold to applicants. The collector sells the rest of the bins' waste to electricity and biofuel production (EB) plant and compost plant. A risk-aversion model has been considered for the EB due to the uncertainty of the amount of recyclable waste, and the model has been verified based on Tehran City.

Comparative analysis of recent metaheuristic algorithms for maximum power point tracking of solar photovoltaic systems under partial shading conditions

<span lang="EN-US">The photovoltaic (PV) system comprises one or more solar panels, a converter/inverter, controllers, and other mechanical and electrical elements that utilize the generated electrical energy by the PV modules. The PV systems are ranged from small roofs or transportable units to massive electric utility plants. The maximum power point tracking (MPPT) controller has been used in PV systems to get the maximum power available. In addition, the MPPT controller is much essential for PV systems to protect the battery devices or direct loads from the power fluctuations received from solar PV panels. There are several MPPT control mechanisms available right now. The most common and commonly applied approaches under constant irradiance are perturb and observe (P&O) and incremental conductance (INC). But such methods show variations in the maximum power point. In this sense, this paper analyses and utilizes two recent metaheuristic algorithms called artificial rabbit optimization (ARO) and the most valuable player (MVP) algorithm for MPPT applications. The performance comparisons are made with the most preferred traditional algorithms, such as P&O and INC. Based on the result obtained, this study recommends that ARO perform better in standard testing conditions than all the other algorithms, but in partially shaded conditions, the MVP algorithm performs better in terms of efficiency and tracking speed.</span>

Eventual Increase in Solar Electricity Production and Desalinated Water through the Formation of a Channel between the Mediterranean and the Dead Sea

Currently, the Israeli energy industry faces the challenge of a considerable increase in solar electricity production. As a relatively isolated system, the significant expansion of solar electricity may cause problems with electricity quality. Electrical storage installation can resolve this problem. In Israel’s situation, the optimal solution could be the creation of a channel between the Mediterranean and the Dead Sea. The channel can solve three closely related problems: the increased production of desalinated water for domestic, industrial, and agricultural needs; the prevention of a permanent Dead Sea level decline and its imminent disappearance; the development of hydro-pumping electrical storage stations; and the creation of numerous PV facilities in the Negev area for national electricity generation. However, detailed analysis should be conducted for the estimation of the possible increase in solar electric generation with consideration of a stochastic PV outcome and the potential ability to use the Dead Sea for the brine discharge of electrical hydro-storage plants.

Modeling and techno-economic analysis of a hybrid sugarcane plant fed by vinasse biogas and bagasse surplus for electricity generation

The growing demand for electricity from renewable energy sources has motivated sugarcane producers to improve the power generation capacity of their plants. In this regard, the present work aims to contribute to the energy recovery process from two sugarcane byproducts: bagasse and vinasse. A novel hybrid combined cycle is devised to use the bagasse surplus generated during the sugarcane season to produce high enthalpy steam for a dedicated condensing turbine. A gas turbine, fed by vinasse biogas vinasse, is used to provide thermal energy to the steam bottoming cycle. Concomitantly, steam for the sugar and ethanol is produced by the existing sugarcane cogeneration system. This approach allows to increase the plant's electricity generation. From a prescribed milling capacity, a conventional sugarcane plant is modeled and validated at steady-state regime. Then, a hybrid plant, designed to consume the bagasse surplus and the vinasse biogas, is presented, and compared to the conventional plant. During the off-season, in the absence of vinasse and biogas, an off-design option is proposed to keep the system running full-time. Results showed that the hybrid plant electricity generation (kWhel) is 7.2–41.5% higher than the conventional plant. The economic feasibility of retrofitting a typical sugarcane plant (live steam parameters at 68 bar/480 °C, for example), by means of a hybrid combined cycle, points to an internal rate of return of around 22.3% and payback period of 5 years. A parametric analysis was carried out showing that, for a process steam consumption below 540kg of steam per tons of sugarcane milled, there will always be leftover bagasse of the season, regardless of the conventional plant steam profile. The production of vinasse required for the hybrid system ranges from 310 to 375 L by tons of sugarcane milled (TC), values within the range of existing sugarcane plants (156–910 L/TC). In addition, the plant operating time can be extended in the off-season, from 200 to 330 days per year, with electrical efficiency achieving around of 27% in this period. In conclusion, the proposed system moves towards the advancement of clean and sustainable electricity generation in the sugarcane industry.

Perovskite Solar Cells: Emerging Photovoltaic Technology for Achieving Net‐Zero Emission Agrivoltaics Ecosystem

The expected population growth and resulting increase in food and energy demands have become global concerns to be addressed with urgent and targeted actions. Agrivoltaics has recently emerged as the practice of co‐locating photovoltaic (PV) infrastructure and agriculture to alleviate land‐use competition between energy and agriculture production. However, PV and agriculture are highly dependent on the utilization of sunlight. Therefore, the design of a PV system is critical for maximizing electricity generation and plant biomass production. Perovskite solar cells (PSCs), as an emerging PV technology, attract intensive attention owing to low fabrication cost, high performance, and tunable transmission. Accordingly, PSCs show promising application in a net‐zero emission agrivoltaics ecosystem. In this perspective, the advantages of PSC‐integrated agrivoltaics are discussed by comparing with traditional PV technologies. Thereafter, the promising and sustainable way is proposed to employ PSCs for electricity generation, plant growth, and aquatic animal development in an agrivoltaics ecosystem. Lastly, a design principle is provided for tailoring PSCs for a sustainable agrivoltaics ecosystem to simultaneously solve the energy and food crises.

Design of Cost-Effective Microcontroller Based Load Controller with Data Logging for Standalone Electric Plant

Maintaining the voltage and frequency fluctuation using a hydraulic governor in Standalone Micro- Hydro Projects (SMHEP) is costlier than the generator itself. So, an Electronics Load Controller (ELC) is used to regulate output power of generator used in the SMHEP. Developments in the ELCs will play an important role in increasing the efficiency and life span of the power plant thereby providing a lot of space for the further improvements. This paper analyzes the current trends and tries to identify their limitations and suggest a novel approach in designing a cost effective ELC system with the capabilities of data logging. In this study software simulation was carried out in Proteus, while the experimental model was designed using microcontroller and integrated sensor system. Both the software and hardware implementations showed positive results. The experiment was carried out under laboratory conditions in which the proposed model successfully diverted the excess power to connected dump loads and allowed the generator to generate the power at full load with efficient data logging and graphical user interface. Keyword: Data Acquisition, Electronic Ballasts, Load Management, Sensor Systems and Applications, Standalone Power Supply

Modelling of Large-Scale Photovoltaic Power Generation System Based on PSCAD and Analysis of Its Stability

In this paper, based on the study of PV power generation principles and mathematical models of PV cells, PSCAD simulation modelling is performed for a large-scale PV plant with required output over 100 MW, and its operational characteristics are analysed. An improved Newton iteration, conductance increment method and semi-aggregate equivalent control algorithm are used to achieve maximum power point tracking (MPPT) for large-sized photovoltaic electricity plant. Finally, the simulation analysis of the large-scale photovoltaic electricity generation system under normal operation and light disturbance is conducted to validate the validity and stability of the model.

Modelling of Electric Power Generation Plant Based on Gas Turbines with Agricultural Biomass Fuel

To ensure the survival of society, an enormous amount of energy is required to sustain the economic and social development of communities. In addition, there is a pressing need to achieve significant reductions in climate change and the associated costs of implementing systems based on traditional energy sources, as well as addressing the issue of providing electricity to isolated areas. In rural environments, there is an alternative energy source with enormous potential, agricultural biomass, which can produce electrical and thermal energy and can progressively help to reduce dependence on fossil fuels. The purpose of this work is to present a dynamic simulation model of a power generation plant that uses the Joule Brayton thermodynamic cycle, based on a gas turbine which is fueled by residual agricultural biomass; the cycle converts mechanical energy to electrical energy. The problem is approached through the characterization of the biomass, mathematical models of the plant components, and simulation of the system behavior in different scenarios. The simulations are processed in Matlab/Simulink, which allows the model to be verified, validating the equilibrium relationship between generation and load demand.

Determination of reliability conditions of reversible water supply systems in thermal power engineering

Today, the most important issues in the national economy of Ukraine are the issues of continuous, reliable and safe operation of reversible water supply systems, namely power units of thermal electric stations and heating plants of industrial enterprises. Trouble-free and reliable operation of water supply systems ensures the normal operation of social and household and industrial enterprises, as well as the safe operation of fire protection systems, which can be disrupted when the supply of a quality product to the consumer is stopped. For the purpose of research to determine the conditions of the reliability of reversible water supply systems in thermal power engineering, as well as the impact of risks in these systems on the reliability of reversible water supply systems, it is proposed to determine the states in which any water treatment system can be and the risks in water treatment systems that are technogenic in origin, and the consequences are ecological. The analysis of the obtained results showed that the states in which the water treatment system can be divided into three classes in accordance with the regulatory documents on the definition of technogenic risks in water treatment systems: class 1 (limit state) - the system works in normal mode, all blocks and elements work without failures and crashes; class 2 (critical state) - the system works in offline mode, some units or elements of the system work in partial failure mode; class 3 (dangerous state) - the system practically does not work and does not purify water, some blocks or elements of the system are in a state of failure. The risks that arise during the operation of water treatment systems and which can be used to assess their technogenic safety can be defined as: a) the probability of this system supplying raw water to the consumer as a result of the failure of blocks and elements of this system - state 3 - dangerous; b) the probability of this system supplying the consumer with poor-quality water as a result of partial failures and freelance work of units and elements of this system - state 2 - critical; c) the probability of this system supplying raw water to the consumer when the system is in state 1 - limiting, due to the natural inertia inherent in the specific physical and chemical processes on which the actual system operates.

Productivity model and experiment of field crop spraying by plant protection unmanned aircraft.

Traditional agricultural production requires numerous human and material resources; however, agricultural production efficiency is low. The successful development of plant protection unmanned aerial vehicles (UAVs) has changed the operation mode of traditional agricultural production, saving human, material, and financial resources and significantly improving production efficiency. To summarize the process of improving the productivity of plant protection UAVs, this study established a productivity calculation model of UAVs based on the time composition of the UAV agricultural plant protection process, including spraying, turning, replenishment, and transfer times. The time required for the unmanned aircraft application process was counted through years of tracking the application process of eight different plant protection unmanned aircraft. Plot lengths of 100, 300, 500, 700, 1,000, 1,500, 2,000, 2,500, 3,000, and 3,500 m were established to calculate the theoretical productivity. The results showed that the productivity of different types of plant protection UAVs increased with an increase in plot length in the range of 100 to 1,500 m; however, when the plot length reached a certain value, the productivity growth rate slowed down or even decreased slightly. Simultaneously, based on the working area per 10,000 mu, the recommended plot length and the number of configured models for different models were recommended. If the plant protection UAV was distinguished by electric and oil power, the time utilization rate of electric plant protection UAVs was 72.7%, and the labor productivity was 56.4 mu/person·h. In contrast, the time utilization rate of the heavy load oil-powered plant protection unmanned aircraft was 86%, and the labor productivity was 63.5 mu/person ·h. This study can support plant protection UAV enterprises to optimize equipment efficiency, provide evaluation methods for the operation efficiency assessment of plant protection UAVs, provide a reference for the selection of plant protection UAVs, and provide a basis for field planning.