How does the CJ19 Series AC Capacitor for Switching Power Capacitors Effectively Suppress the Inrush Current during Closing？

In low-voltage reactive power compensation systems, the inrush current problem that may occur when power capacitors are switched has always been a terrorist affecting the service life of equipment and the stability of the power grid. There are countless traditional inrush flow suppression schemes. Although they can all alleviate inrush flow, they generally have disadvantages such as large volume, high cost, complex maintenance and etc. Therefore, the CJ19 series AC capacitors for switching power capacitors of Geyue Electric stand out with their unique design and advanced inrush current suppression technology, becoming the preferred solution in the industry. Please follow the insight of the Chief Electrical Engineer of Geyue Electric to learn how the CJ19 series AC contactors of Geyue Electric effectively suppress the inrush current during closing.

The hazards of inrush flow during closing and the limitations of traditional suppression methods

When power capacitors are put into operation in the power grid, due to the possible phase difference between the initial voltage and the grid voltage, an inrush current (i.e., closing inrush current) as high as 20 to 50 times the rated current is generated instantaneously. This inrush current is highly likely to cause very serious harm to the low-voltage reactive power compensation system. This inrush current may damage the capacitor replacement, causing the internal insulation of the capacitor to age and shortening its service life. This inrush current may affect the contacts of the contactor, corroding the contacts and reducing the reliability of the contactor. This inrush current may also cause a sudden drop in grid voltage, affecting the operation of other sensitive equipment in the circuit. To eliminate the above-mentioned hazards, we must intervene by means of suppressing harmonics. There are many traditional methods for suppressing inrush flow during closing, but each of them has its own drawbacks: For instance, suppressing inrush current by series current-limiting reactors will increase costs and volume, and may cause harmonic amplification problems. Suppressing inrush current by switching thyristors (thyristors) will lead to severe heating of capacitors. The method of suppressing harmonics by adopting a delayed switching strategy can only alleviate part of the inrush current generation but cannot completely eliminate it. Compared with the traditional methods for suppressing inrush current during closing mentioned above, the CJ19 series AC contactors developed by Geyue Electric provide a more efficient solution for suppressing inrush current during closing in low-voltage reactive power compensation systems by optimizing mechanical structure and electrical design.

The core technologies and working principles of the CJ19 series AC contactors

The core technologies of the CJ19 series AC contactors of Geyue Electric mainly focus on three aspects: dual-stage switching design, magnetic blowout arc extinguishing technology and intelligent control compatibility. The CJ19 series AC contactors are the products of Geyue Electric that have been structurally optimized based on the ordinary AC contactors. The CJ19 series AC contactors adopt a dual-stage design of "pre-charging resistor + main contact" in their structure: During the pre-charging stage, the CJ19 series AC contactors pre-charge the capacitor through a current-limiting resistor (usually a low-resistance alloy resistor) to limit the initial current peak. When the voltage of the capacitor approaches the grid voltage, the main contacts of the CJ19 series AC contactor close to achieve smooth switching and avoid large current impact. Due to the high arc energy when power capacitors are switching, the magnetic blowout arc extinguishing technology endowed to the CJ19 series AC contactors of Geyue Electric takes advantage of the superior property of electromagnetic force to rapidly elongate and cool the arc, minimizing the erosion of the contactor's contacts and further extending the service life of the contactor and other equipment in the circuit. In addition, the CJ19 series AC contact's super intelligent compatibility enables it to be used in conjunction with Geyue Electric's intelligent power compensation controllers (such as the JKW series power factor correction controllers) to achieve zero-voltage switching without insurge current and a group switching strategy that optimizes compensation accuracy.

Practical application cases and performance comparison

Geyue Electric is committed to providing professional low-voltage reactive power compensation solutions for clients in all industries and solving various problems in the field of low-voltage reactive power compensation. A certain automobile manufacturing plant originally used a scheme of ordinary contactor + reactor, but the problem of contact burnout occurred frequently. After the automobile factory cooperated with our company, our company proposed to replace the ordinary contactors in the original reactive power compensation plan with Geyue Electric’s CJ19-63A contactors. After the replacement was completed, the inrush current in the low-voltage reactive power system of the automobile manufacturing plant was reduced by 80%, the lifespan of the contactor was increased by three times, and the annual maintenance cost dropped by 60%. Besides, in the reactive power compensation cabinet of a certain photovoltaic power station, CJ19-95A AC contactors of Geyue Electric successfully dealt with frequent switching and high harmonic environments, operated stably, and no abnormal heating or contact adhesion problems occurred. Compared with the traditional switching scheme that combines traditional contactors and reactors, Geyue Electric’s CJ19 series AC contactors have a stronger inrush current suppression capability, a more compact size, lower cost, lower maintenance frequency and longer service life.

Future development trends and industry application prospects

With the popularization of smart grids and new energy power generation, the reliability requirements for reactive power compensation equipment are getting higher and higher. The technical advantages of Geyue Electric’s CJ19 series AC contactors make them have broad prospects in emerging fields such as industrial automation, data core, medical care, and electric vehicles. In the future, Geyue Electric will also launch an intelligent CJ19+IoT monitoring version to achieve remote status monitoring and predictive maintenance, further enhancing the user experience.

Geyue Electric’s CJ19 series AC contactors for switching power capacitors effectively solve the inrush current problem during closing through dual-stage switching, magnetic blowing arc extinguishing and intelligent compatibility design, enhancing system reliability while reducing costs. Whether in the fields of industrial power distribution, new energy or emerging power electronics, Geyue Electric’s CJ19 series AC contactors for switching power capacitors have demonstrated outstanding applicability. If you are looking for an efficient and stable reactive power compensation solution, Geyue Electric’s CJ19 series AC contactors are undoubtedly the ideal choice! If you are interested in purchasing AC contactors for switching power capacitors, please see the product details on www.geyuecapacitor.com, please contact Geyue Electric via info@gyele.com.cn.