This article focuses on the development of a system based on the long-range network (LoRa), which is used for monitoring the agricultural sector and is implemented in areas of the Andean region of Ecuador. The LoRa network is applied for the analysis of climatic parameters by monitoring temperature, relative humidity, soil moisture and ultraviolet radiation. It consists of two transmitter nodes and one receiver node, a LoRa Gateway with two communication channels for data reception and one for data transmission, and an IoT server. In addition, a graphical user interface has been developed in Thinger.io to monitor the crops and remotely control the actuators. The research conducted contains useful information for the deployment of a LoRa network in agricultural crops located in mountainous areas above 2910 m.a.s.l., where there are terrains with irregular orography, reaching a coverage of 50 hectares and a range distance of 875 m to the farthest point in the community of Chirinche Bajo, Ecuador. An average RSSI of the radio link of −122 dBm was obtained in areas with a 15% slope and 130 m difference in height according to the Gateway, where the presence of vegetation, eucalyptus trees and no line-of-sight generated interference to the radio signal. The success rate of PDR packet delivery with an SF of nine, had a better performance, with values of no less than 76% and 92% in uplink and downlink respectively. Finally, the technological gap is reduced, since the network reaches places where traditional technologies do not exist, allowing farmers to make timely decisions in the production process in the face of adverse weather events.

/pdf/lora-network-based-system-for-monitoring-the-agricultural-1teejfqp.pdf

LoRa Network-Based System for Monitoring the Agricultural Sector in Andean Areas: Case Study Ecuador

This work presents a topological configuration that allows the input stage of a double conversion UPS to be used as a three-phase rectifier and a DC/DC voltage boost converter in normal and backup operating mode, respectively. Thus, the use of a specific circuit for the discharge of the battery bank, which would be rated for UPS nominal power, is avoided. The operation analysis of the proposed input stage is presented, as well as the mathematical modeling and the control system that guarantee the applicability in the input power factor correction, DC bus voltage control and for the DC bus capacitors voltage balance. Hardware-in-the-loop results are acquired for a 20 kVA three-phase UPS to validate the developed analysis besides to demonstrate the good performance of the system.

Input Stage With Double Functionality Applied To A High Performance Three-phase Ups

This article focuses on the development of a system based on the long-range network (LoRa), which is used for monitoring the agricultural sector and is implemented in areas of the Andean region of Ecuador. The LoRa network is applied for the analysis of climatic parameters by monitoring temperature, relative humidity, soil moisture and ultraviolet radiation. It consists of two transmitter nodes and one receiver node, a LoRa Gateway with two communication channels for data reception and one for data transmission, and an IoT server. In addition, a graphical user interface has been developed in Thinger.io to monitor the crops and remotely control the actuators. The research conducted contains useful information for the deployment of a LoRa network in agricultural crops located in mountainous areas above 2910 m.a.s.l., where there are terrains with irregular orography, reaching a coverage of 50 hectares and a range distance of 875 m to the farthest point in the community of Chirinche Bajo, Ecuador. An average RSSI of the radio link of -122 dBm was obtained in areas with a 15% slope and 130 m difference in height according to the Gateway, where the presence of vegetation, eucalyptus trees and no line-of-sight generated interference to the radio signal. The success rate of PDR packet delivery with an SF of nine, had a better performance, with values of no less than 76% and 92% in uplink and downlink respectively. Finally, the technological gap is reduced, since the network reaches places where traditional technologies do not exist, allowing farmers to make timely decisions in the production process in the face of adverse weather events. 

/pdf/lora-network-based-system-for-monitoring-the-agricultural-3ew62f9m.pdf

— The way to increase the convenience of waste container users and monitor the level of waste container content can be by utilizing IoT technology and building an intelligent waste container system. Therefore, this study aims to conduct research and development (R&D) of an Internet of Things (IoT) control system to automatically open and close the lid of trash containers and detect the fullness of garbage in trash containers. This research method is a combination of experimental and survey methods. The research results show that the waste container control system effectively opens and closes the lid of the garbage container at a distance of about 40 cm between the distance ultrasonic sensor of garbage containers and users. In addition, the garbage janitor can monitor the level of garbage that is filled in the garbage container correctly through the website and telegram on his cell phone, and users of trash containers are more comfortable disposing of waste.

IoT-Based Garbage Container System Using NodeMCU ESP32 Microcontroller

This paper describes the process of designing, building, and evaluating an IoT (Internet of things) ecosystem for three wireless technologies LoRa, Wi-Fi, and BLE. The system has a gateway connected to the internet by LTE and interacts with three sensor nodes; each sensor node uses a different wireless technology. The hardware control device is a Raspberry Pi3, the IoT web platform is a component of Azure. The development provides a flexible, autonomous, heterogeneous, and scalable network for IoT ecosystems that can analyze the real-time of each technology in the ecosystem. For this work real-time means a latency that has a value between 101 ms (milliseconds) and 6012 ms. Performance evaluation results using latency tests and maximum data sending range for each technology shows that the maximum range is 318 meters, and the lowest average latency is 1033 ms in LoRa and LTE interoperability. 

Prototype for evaluation of wireless technologies in IoT ecosystems

In this article, the authors present an Internet of Things (IoT) solution for controlling and monitoring a low power photovoltaic system (250 W). Power conditioning is performed by a DC-DC Flyback converter with active clamping. An ESP32 microcontroller is used to implement an output voltage control loop and to communicate, online and in real time, with an internet server. The effectiveness of voltage regulation is proven with experimental results and the authors present evidence that the IoT features work properly.

Control and monitoring of a Flyback DC-DC converter for photovoltaic applications using embedded IoT system

This paper introduces a control algorithm for a multifunctional, three-phase, four-wire ac-dc converter. The converter is so-called multifunctional because it operates as a battery charger and as a load power supply. In other words, two different loads in parallel are simultaneously connected to the converter. The proposed algorithm can be applied to nonisolated three-phase UPS (uninterruptible power supply) systems, and electric vehicle (EV) battery charging systems. Relevant features of the proposed approach are power factor correction, common neutral point between the input and output facilitates the installation of the bypass circuit, balanced and symmetrical output voltages that allow the use of inverters with neutral point, and control of the battery current. The operation principle of the proposed algorithm is discussed in detail, while experimental results are also presented. 1

/pdf/proposal-of-a-control-algorithm-applied-to-a-threephase-four-13izoktiuc.pdf

Antonio Wallace Neres da Silva

Papers

Control and monitoring of a Flyback DC-DC converter for photovoltaic applications using embedded IoT system

Proposal of a Control Algorithm Applied to a Threephase, Four Wire, AC-DC Converter for EV and UPS Applications