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This post was last edited by sdscj0122 on 2020-3-17 at 16:05. A smart lightning protection system integrates cloud computing, mobile internet, and Internet of Things technologies into comprehensive lightning protection measures. Through the integration of software and hardware systems, it enables lightning warnings, intelligent lightning protection, and intelligent monitoring in specific areas, transforming passive lightning protection into active forms in order to achieve proactive prevention of lightning-related disasters and thus effectively reduce the risk of lightning strikes. Junhe Electronics shares with you the components of intelligent lightning protection systems, as follows: 1. Lightning early warning and forecasting – The most direct methods of monitoring at present are through atmospheric electric field meters and lightning location systems. Lightning phenomena result from the accumulation of large amounts of charge within thunderclouds, and changes in the intensity of the atmospheric electric field indicate the degree to which the charge in those clouds triggers lightning. Thunderstorm clouds become charged and accumulate, creating a strong electric field that causes metals to develop induced charges under the influence of this electric field force. It is highly scientific to issue early warnings and forecasts about the timing, location, intensity, and movement direction of lightning disasters by monitoring the polarity, intensity, distribution, and development of strong charges within thunderstorm clouds. II. Online Monitoring System for Lightning Protection Facilities: The online monitoring system for lightning protection facilities utilizes the combination of the Internet of Things and cloud storage technologies to enable online monitoring of lightning protection as well as other environmental factors. The online monitoring system for lightning protection facilities mainly monitors parameters such as grounding resistance, lightning current, and surge protectors (SPDs). The components of this system are as follows: 1. Online lightning current monitoring. Online lightning current monitoring makes use of Rogowski coil sensor technology to accurately determine the peak value, polarity, and energy of lightning strikes. It enables online monitoring of the peak value, polarity, and energy of one channel of lightning current, as well as data on the timing and frequency of lightning strikes, and it can issue alerts promptly after a lightning strike occurs. Lightning current monitoring involves using flexible Rogowski coils to detect lightning current data; current transformers are used for measurement, and the output signal is the derivative of the current with respect to time. This derivative signal, once passed through an integrator, allows for an accurate representation of the actual current being measured. 2. The basic principles for online monitoring of grounding resistance using an online grounding resistance monitor are the three-point method (up to 6 points can be measured) and the loop method. The principle of the loop method is as follows: The sensor consists of a voltage coil and a current coil. The voltage coil first sends an excitation pulse signal to the ground circuit under test, which induces a pulse potential E in that circuit; under the influence of this potential E, a current I is generated in the circuit under test. The sensors measure E and I respectively, and the resistance of the circuit under test can be obtained using the formula: R = E/I. It can monitor online the connection status of grounding leads, the loop grounding resistance, and the connection resistance of metal circuits, enabling functions such as online testing, contactless measurement, and real-time monitoring. Models equipped with an LCD display allow for the direct viewing of the ground resistance measurement values on-site. It is also possible to set the upper limit value for alarms related to ground resistance through the buttons; when the measurement values exceed this limit, alarms are triggered both audibly and visually. 3. Online monitoring of surge protectors (SPDs): Online monitoring of SPDs focuses primarily on the degree of degradation of the SPDs, remote status signals from the SPDs, the number of times the SPDs have been activated, the status of air switches, three-phase voltage, as well as environmental temperature and humidity. Surge protector (SPD) leakage current monitoring: μA-level leakage current sensors are used. It is a measurement module that utilizes the principle of zero-flux electromagnetic induction to convert the AC leakage current (a small current) under measurement into a voltage or current signal that is output in proportion. It features high precision, high linearity, high integration level, a small size and simple structure, stable operation over long periods, and the ability to function in various working environments ； Remote signaling monitoring of surge protectors (SPD): When the tripping mechanism of a surge protector (SPD) is activated, it causes the remote signaling alarm switch to operate. The microcontroller in the intelligent analyzer detects this change in the state of the remote signaling alarm switch and triggers an alarm to indicate that the SPD has failed ； Monitoring of the number of times the surge protector (SPD) activates: It is equipped with a lightning strike counter sensor (current transformer); when the SPD activates, the microcontroller inside the analyzer detects the current value sensed by this sensor, and after making a judgment, it determines whether to increment the count by one ； Air circuit breaker status monitoring: The output voltage value (analog signal) at the circuit breaker terminal is detected using a microcontroller to determine whether the circuit breaker has tripped ； Three-phase voltage monitoring: The implementation of this function is primarily achieved through current-type voltage transformers, dedicated three-phase power measurement chips, and microcontrollers. 4. Online Monitoring and Management Platform for Lightning Protection Facilities: This platform utilizes smart gateways to receive monitoring data on lightning current, ground resistance values, surge protectors (SPDs), etc. It analyzes this data and issues alerts immediately when values exceed normal limits, thereby improving the level of safety management. http://www.junhedianzi.cn/uploads/ueditor/image/20200313/1584069516494924.jpg The above components are the main elements of intelligent lightning protection systems, and they play a crucial role in protecting against lightning strikes; they are suitable for use in various industries such as communications, petroleum and petrochemicals, electricity, and transportation.