Abstract: This paper introduces the background of the research and development of intelligent integrated power capacitors, focusing on the intelligent reactive power compensation technology based on the dual-CPU technology combining digital signal processor (DSP) and microcontroller, integrating zero-crossing switching of composite switches and computer intelligent network module technology, thus realizing the requirements of modern distribution networks for reactive power compensation, energy saving, zero-crossing switching, and intelligent networking. Keywords: Intelligent integrated capacitor; zero-crossing switching. Distribution networks cover a wide area, have diverse users and complex loads, and suffer from insufficient reactive power compensation, high failure rate of reactive power compensation devices, difficulty in maintenance, large active power losses, and large inrush currents during switching. Strengthening and improving the reactive power compensation of distribution networks is of great significance for reducing losses and improving voltage quality. 1 Research and Development Concept of Intelligent Integrated Power Capacitors With the rapid development and widespread application of microelectronics technology, digital control technology, and communication and network technology, electrical appliances are developing towards compact, modular, and combined types. Intelligence, integration, networking, energy saving, and environmental protection have become the mainstream of intelligent electrical appliance development. Intelligent integrated power capacitors are a brand-new low-voltage reactive power compensation device developed within the overall development framework of intelligent electrical appliances. It consists of an intelligent measurement and control module, a thyristor composite switch module, a line protection module, and power capacitors, replacing the original automatic reactive power compensation device, which was composed of scattered components such as intelligent controllers, fuses, composite switches or mechanical contactors, thermal relays, low-voltage power capacitors, and indicator lights connected by wires inside and on the cabinet. It changes the outdated controller technology and mechanical contactors of traditional reactive power compensation devices, as well as the electromechanical integrated switch used for capacitor switching. It also changes the bulky and cumbersome structure of traditional reactive power compensation devices, resulting in a new generation of low-voltage reactive power compensation equipment with better compensation effect, lower power loss, smaller size, greater cost savings, more flexible use, easier maintenance, longer service life, and higher reliability, meeting the higher requirements of modern power grids for reactive power compensation. 2. Technological Innovation The innovation of the intelligent integrated power capacitor lies in the adoption of an imported chip digital signal processor (DSP) and the application of dual watchdog technology, which improves the reliability of intelligent control. The system employs electronic real-time detection signal feedback, contactless photoelectric triggering technology, and a composite switching technology combining thyristors and magnetic latching relays to achieve equal-voltage switching, realizing true "zero-crossing switching." Inrush current is virtually zero, eliminating harmonic injection. Computer intelligent network technology is used to decentralize control and improve reliability. 2.1 Zero-Crossing Switching Because the intelligent integrated power capacitor possesses the most advanced "zero-crossing switching" function currently available in China, it ensures no inrush current impact, no operational overvoltage, and no arc reignition during capacitor switching, improving control speed and extending capacitor lifespan. Traditional reactive power compensation devices use AC contactors for switching. When the AC contactor disconnects the capacitor, it generates a very high operational overvoltage, a significant factor leading to capacitor damage. (See Figures 1 and 2.) Figure 1: Impact of Zero-Crossing and Non-Zero-Crossing on Capacitor Failure Rate; Figure 2: Impact of Zero-Crossing and Non-Zero-Crossing on Capacitor Attenuation Rate. After adopting zero-crossing switching technology, the capacitor's lifespan is extended by more than two times, resulting in immeasurable economic and social benefits. 2.2 Intelligent Network Control Since each capacitor is equipped with an intelligent network module, it can form a master-slave automatic switching mode, meaning each capacitor can act as a controller, achieving high reliability. The central controller is eliminated, and a distributed control mode is adopted. Each group of intelligent integrated power capacitors has a control unit, freeing the automatic switching of multiple capacitor groups from reliance on a single controller and preventing system paralysis due to controller failure. Furthermore, when multiple intelligent integrated power capacitors are networked, a network is automatically generated, with the one with the smallest address code as the master and the rest as slaves, forming a low-voltage reactive power automatic control system. If an individual slave fails, it automatically disconnects without affecting the operation of the remaining slaves. If the master fails, it also disconnects, and a new master is generated from the remaining slaves, forming a new system. Capacitors of the same capacity are switched according to a cyclic switching principle, while capacitors of different capacities are switched according to an appropriate compensation principle. It also has a 485 communication interface, allowing connection to a backend computer for comprehensive power distribution management. In summary, this product, employing intelligent network technology, greatly improves operational reliability and ensures sufficient capacitor deployment, effectively extending the lifespan of the compensation device. Although the price of intelligent integrated power capacitors is higher than that of traditional capacitors of the same capacity when using reactive power compensation devices of the same capacity, the cost of intelligent integrated capacitors is cheaper compared with the overall reactive power compensation device and the entire life cycle. 2.3 Intelligent compensation: Its intelligent fully automatic combined control mode can use multiple parameters such as reactive power, power factor, and reactive voltage as control parameters to achieve the best compensation combination. Hybrid compensation is the mode of optimizing the compensation effect. Intelligent integrated power capacitors can easily and reliably achieve the compensation requirements of complex optimal effects such as phase compensation and hybrid compensation. 3 Performance 3.1 Significant energy saving effect: Intelligent integrated power capacitors use magnetic latching relays. After the circuit is turned on, the armature inside the magnetic latching relay is held by a permanent magnet. Conventional compensation devices require AC contactors to turn on the compensation circuit. The contacts of AC contactors need to be held by electromagnetic coils. Each AC contactor (calculated according to the holding capacity of CJ19 relay) has a power of 15W, and each circuit can connect a 15kvar capacitor. Using intelligent integrated power capacitors reduces power loss by 1W per kvar compared to traditional reactive power compensation devices. Furthermore, intelligent integrated power capacitors are approximately 50% smaller than other automatic compensation devices, thus significantly reducing energy losses from wires, contacts, and other components. Currently, my country has nearly 5 million distribution transformers in use (data from the State Electricity Regulatory Commission of China), with an average capacity of 200kVA and a total capacity of nearly 1000GVA. Assuming reactive power compensation is one-third of the average for distribution transformers, existing distribution transformers require a reactive power compensation capacity of 330Gvar. If existing traditional reactive power compensation devices in distribution transformers were replaced with intelligent integrated power capacitors, saving 1W of power per kvar (not even considering reduced energy losses from wires and contacts), 2891GWh of electricity could be saved annually. This would reduce coal consumption by 1.0986 million tons (coal consumption for power supply is 380g/kWh) and CO2 emissions by 2.86 × 10⁶ tons. Reduces SO2 emissions by 5.7 × 10⁴ t and NO₂ and NO₂ emissions by 3.36 × 10⁴ t. 3.2 High level of intelligence and leading switching technology, resulting in optimal compensation effect. 3.3 Extended lifespan and significantly improved reliability, with a lifespan reduction of several times. Due to the application of zero-crossing switching technology and intelligent network control technology, its reliability is greatly improved, and its lifespan is extended. In addition, we have pre-installed a thermal sensing probe inside the product, and through a temperature control module, we prevent the hottest spot from overheating, effectively extending the product's thermal aging lifespan. 3.4 Significantly reduced size. The intelligent integrated power capacitor is highly integrated, compact in structure, and lightweight. Using it in a cabinet, the maximum capacity can reach 800 kvar, and the volume of the same capacity is reduced by about 50% compared to other automatic compensation devices. Especially in urban power distribution rooms where land and housing resources are very scarce, for indoor power distribution rooms above 630 kVA, the traditional reactive power compensation device requires two cabinets; using intelligent integrated power capacitor cabinets, only one cabinet is needed to meet the compensation requirements. 3.5 Modular Structure, Simple Wiring, Convenient Expansion, and Easy Maintenance: The intelligent integrated power capacitor achieves standardization and modularity, replacing traditional controllers, air switches, AC contactors, thermal relays, and capacitors into a single unit. During panel installation, a modular stacking method is used. Multiple capacitor panels reduce production time by over 60% compared to traditional methods, while also reducing connecting wires and contact points by 80%. The cabinet is simple, allowing for rapid on-site assembly. The product is small in size and has simple wiring. As the power load increases, the number of capacitors can be added at any time, overcoming the limitations of conventional methods due to complex and unchanging wiring. The product itself is highly intelligent, very easy to install, and convenient to maintain. If a fault indicator light on the product panel illuminates, simply remove the faulty capacitor and replace it with a new one—as easy as replacing a battery. 4. Application Significance and Prospects The new Energy Conservation Law legally establishes resource conservation as a basic national policy in China, and energy conservation has become a shared responsibility of the entire society. The "zero-crossing switching" technology for capacitors has become an advanced technical requirement for next-generation reactive power compensation devices. This requirement has been specified in bidding documents in multiple regions, making widespread adoption inevitable. This product is a new generation of energy-saving products for power systems, a replacement for conventional reactive power compensation products. Intelligent integrated power capacitors offer advantages such as energy saving, miniaturization, superior performance, and low cost, making them excellent next-generation intelligent electrical products and ideal reactive power compensation equipment. Their outstanding advantages in saving energy and space resources will make a significant contribution to building a harmonious society. References [1] Lu Baosong. Reactive power compensation of urban low-voltage power grid [J]. China Electric Power, 1996, 29(3): 54-57. [2] Shi Xinchun, Peng Wei. A TSC low-voltage reactive power compensation device with zero-voltage switch [J]. Power Grid Technology. [3] Zhu Haisong. The influence of parallel reactive power compensation device on power grid harmonics [J]. Power Capacitor, 2005(2): 19-22. [4] Lu Anding. Reactive power of power system [M]. 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