China Zhenglan Cable Technology Co., Ltd Company News

Dear All, Here comes China's traditional Dragon Boat Festival. We will be on holiday from Friday (June 3rd) to Sunday (June 5th). Work resume from June 6th(Monday). During holiday, we may have limited access to email, so shall any delays of response. Kindly ask for your understanding. Zhenglan Cable Technology Co., Ltd June 1st, 2022

Transmission process The transmission of electric energy, together with power transformation, distribution and consumption, constitutes the overall function of the power system. Through power transmission, the power plants far away (up to thousands of meters) are connected with load centers, so that the development and utilization of electric energy go beyond the regional limits. Transmission lines can be divided into overhead transmission lines and underground transmission lines according to their structural forms. The former consists of line towers, conductors and insulators, which are erected on the ground; The latter is mainly laid underground (or underwater) with cables. Transmission can be divided into DC transmission and AC transmission according to the nature of the transmitted current. This process uses different types or overhead bare conductors such as AAC, AAAC, ACSR, etc. Transformation process In the power system, the power plant converts the natural primary energy into electric energy and sends power to the remote power users. In order to reduce the power loss on the transmission line and the line impedance voltage drop, it is necessary to increase the voltage; In order to meet the security needs of power users, the voltage should be reduced and distributed to each user, which requires a substation that can increase and decrease the voltage and distribute power. Therefore, the substation is an electrical device in the power system that converts voltage, receives and distributes electric energy through it. It is an intermediate link between the power plant and power users. At the same time, the power grid of various voltage levels is connected through the substation. The function of the substation is to transform voltage, transmit and distribute electric energy. The substation is composed of power transformer, power distribution device, secondary system and necessary auxiliary equipment. The transformer is the central equipment of the substation, which uses the principle of electromagnetic induction. This process uses different types of cables such as high voltage, medinum voltage and low voltage power cable, aerial bundled cable, electrical wires.

During the construction of a solar photovoltaic power station, in addition to the main equipment, such as photovoltaic modules, inverters, and step-up transformers, the photovoltaic cable materials connected to the photovoltaic power station have the same effect on the overall profitability, operation safety, and high efficiency of the photovoltaic power station. plays a vital role.. According to the system of solar photovoltaic power station, cables can be divided into DC cables and AC cables. According to the different uses and use environments, they are classified as follows: 1. DC cable (1) Serial cables between components. (2) Parallel cables between the strings and between the strings and the DC distribution box (combiner box). (3) The cable between the DC distribution box and the inverter. The above cables are all DC cables, and there are many outdoor layings. They need to be moisture-proof, sun-proof, cold-resistant, heat-resistant, and UV-resistant. In some special environments, they also need to be protected from chemicals such as acid and alkali. 2. AC cable (1) The connecting cable from the inverter to the step-up transformer. (2) The connecting cable from the step-up transformer to the power distribution device. (3) The connecting cable from the power distribution device to the power grid or the user. This part of the cable is an AC load cable, which is laid in the indoor environment and can be selected according to the general power cable selection requirements. 3. Photovoltaic special cable A large number of DC cables in photovoltaic power plants need to be laid outdoors, and the environmental conditions are harsh. The cable materials should be determined according to the resistance to ultraviolet rays, ozone, severe temperature changes and chemical erosion. The long-term use of ordinary material cables in this environment will cause the cable sheath to be fragile, and even decompose the cable insulation. These conditions will directly damage the cable system, but also increase the risk of short-circuiting the cable. In the medium and long term, the possibility of fire or personal injury is also higher, which greatly affects the service life of the system. 4. Cable conductor material Most of the DC cables used in photovoltaic power plants work outdoors for a long time. Due to the limitation of construction conditions, connectors are mostly used for cable connection. Cable conductor materials can be divided into copper core and aluminum core. 5. Cable insulation sheath material During the installation, operation and maintenance of photovoltaic power plants, cables may be routed in the soil below the ground, in overgrown rocks, on the sharp edges of roof structures, or exposed to the air, and the cables may be impacted by various external forces. If the cable jacket is not strong enough, the cable insulation will be damaged, affecting the service life of the entire cable, or causing problems such as short circuits, fire and personal injury hazards.

Dear All, Wish you a happy International Workers' Day. Hope all of your efforts will be rewarded and all of your hard work will have gains. China's legal holiday for this will be from April 30th(Saturday) till May 4th(Wednesday). Work resume from May 5th( Thirsday). During holiday, we may have limited access to email, so shall any delays of response. Kindly ask for your understanding. Zhenglan Cable Technology Co., Ltd April 30th, 2022  

Power cables are one of the indispensable materials for power transmission and are widely used in economic production. Once a cable fails, it will not only threaten the safe and stable operation of the power grid, but also cause significant economic losses to families and society. Now there are many unqualified cables in the market that are confusing consumers' choices with fake and shoddy cables. The following will introduce the identification method of inferior cables. 1. Unqualified wires and cables   Marking is the main way to identify the basic information of products using wires and cables. According to the standard, the main contents of the mark are: product model, specification, standard, manufacturer, origin, etc. within a certain marking distance. When the mark is unqualified, it will cause Construction personnel identify errors, and in severe cases, construction personnel identify faults that can lead to electrical accidents.  

The rapid development of electric power industry has promoted the development of the electrical industry supporting the electric power industry, especially the wire and cable industry. The variety development of wire and cable shows a diversified trend. Wires and cables have developed from simple power transmission to multi-function, that is, some new characteristics have been added according to different uses, such as the water resistance requirements of power cables. With the deepening of the research and understanding of insulation water absorption and water tree, people are more and more aware of the importance of waterproof performance for medium and high voltage power cables. In areas with high groundwater level or perennial rainfall. More and more users require waterproof performance for cables.   After water is immersed in the cable, the main influence is on the conductor and insulation of the cable. As far as the conductor is concerned, the cable is in a thermal stable state during normal operation, and the conductor temperature is generally above 60. If there is water immersion, it will lead to conductor oxidation and increase the energy loss resistance between conductor single wires, which increases the conductor resistance and the energy loss of transmission line, In terms of insulation, although polyethylene is a non-polar hydrophobic material that is very difficult to dissolve in water, polyethylene is a semi crystalline polymer composed of crystalline phase and amorphous phase. The phase structure of polyethylene is compact, but there are defects at the grain boundary; The molecular arrangement in the amorphous phase is loose. There is a large gap between molecules. Water molecules are polar. Under the combined action of diffusion force and electric field force under alternating electric field, water molecules can easily penetrate into the capacity gap of amorphous phase and grain boundary defects of crystalline phase of polyethylene. The above problems also exist in the molecular structure of cross-linked polyethylene. At the same time, there are many cross-linked by-products in cross-linked polyethylene as impurities, so cross-linked polyethylene also has large water absorption under alternating electric field. Cross linked polyethylene and polyethylene insulation will produce water tree after absorbing water, which will cause breakdown and damage to the running cable.   Zhenglan Cable Technology Co., can do radinal water prevention structure by adding water prevention tape into different layer of the MV cable. If you are looking for such performance for MV cable, please come to us.