Distribution Transformer Industry Analysis

From the point of view of industry development, the market for distribution transformers is huge and shows a trend of rapid growth. However, the entry threshold for the industry is low. Large and medium-sized enterprises coexist with “workshop” companies, so the overall level of technology is not high. Many companies are chaotic, the market is fierce, and the quality of products is uneven.

Problems in the production area highlight From the production field perspective, there are three main problems:

First, the quality concept is not strong. Transformer production is a labor-intensive industry and about 70% of the work needs to be done manually. Because the company's quality awareness is not strong, the training and management of product quality is not enough, causing internal and external quality problems from time to time. For example, the weld seam is rough and the design of the component parts is outdated, which directly leads to the appearance of the product being rough, the damage index being poor, the paint falling off and the gloss being low.

Second, the material shoddy. Some transformer companies replace their shells with old transformers for the benefit of the eyes, and they will serve as new transformers after refurbishment. Some transformer windings will be sold on behalf of copper wire on aluminum wires, and iron cores will use scrap silicon steel sheets (commonly known as secondary sheets). These substandard falsified behaviors have seriously affected the normal business order of the entire industry. Vicious low-cost competition among enterprises has led to a vicious cycle of product quality and has caused great harm to companies that conduct business in good faith. After the transformer is put into operation due to fraud, it will bring serious quality hidden troubles and high losses, and bring environmental pollution.

Third, some manufacturers lack of R&D and design capabilities. Because many domestic companies are limited by their development capabilities and lack the original accumulated data, the design has certain blindness. Even some transformer companies often copy advanced technologies and production drawings of others due to financial and manpower limitations, but they are not completely absorbed and digested. Due to problems in the handling of certain links and the control of details, they cause product quality defects. .

Supervision or storage blind spots At present, due to the large number of transformer manufacturing companies and the existence of vicious competition in the market, there are various problems in the quality of transformer products. For product quality supervision departments, the difficulty of supervision and inspection increases.

First, the rapid development of transformers, the corresponding standard lags behind. At present, the transformer model has developed rapidly. In the short years, oil-filled transformers have appeared in S13 and S14 respectively, but the national standards have not yet clearly defined the performance parameters for S14, which obviously lags behind the development of product models.

Second, the cottage transformer factory, quality supervision department supervision is difficult. The development of high profits and technology has resulted in a large number of “shanzhai” factories, and even some “shanzhai” factories have no quality management regulations, and their life cycle is very short, ranging from 3 to 5 years, and less than 1 year. The supervision of the product quality supervision department has brought greater difficulties.

Improper use of implied hidden national standards, standards and corporate standards have very specific requirements for the technical requirements of the transformer, and "Transformer Selection Guide" on the selection of transformer technical parameters and principles also have clear steps. However, in fact, many technology agreements are not completely selected according to the steps and principles stipulated in the standards. Many non-conformist terms are blindly included in the technical agreement, which brings hidden dangers to product quality.

The technical standards of products, whether they are equivalently adopted by the IEC standard or self-developed, have their own limitations in terms of time and space. In addition, the country has a vast territory and the power system is extremely complex. Therefore, the users have to rely on their own special needs. The technical agreement required to be included in the ordering contract is undoubtedly incontrovertible, but the problem is that the reasonableness of some requirements is debatable, especially if there is some disregard for the actual situation.

First, capacity issues. Users and design institutes often determine the transformer capacity based on the development of the load, plus a certain margin, and add all the peak loads together to determine the load base value. In fact, any load is in change, and it is impossible to maintain the maximum load in 24 hours. Therefore, how to determine the capacity value when changing the load is very important, because the capacity is too large or too small may cause waste or affect the operating life.

The IEC standard and national standard have "load guidelines", and there are very detailed regulations and calculation methods for overload operation of transformers, which also means that short-time overload operation of transformers is a normal operation mode. Due to the concern that the capacity is too large due to overloading, the hot spot temperature of the winding insulation is increased and the life of the transformer is lost.

The actual situation is that most transformers are not allowed to overload, which makes the selection of product capacity tends to be too large, invisible increase in investment and loss. Of course, there are also other extreme situations. For example, for the sake of economic benefits, many small distribution transformers have a small capacity and tend to operate in an overloaded state for a long time. Both of these situations should be unscientific.

Second, the voltage problem. The poor determination of the voltage value of the transformer will cause the selected voltage rating of the transformer to be very different from the actual condition of the system. This is especially true for transformers used at the end of the line. Transformer over-excitation also occurs due to the transformer's rated voltage being lower than the actual system voltage. The most common consequence is an increase in the unit loss index of the silicon steel sheet and a rapid increase in the core temperature, which results in accelerated aging of the insulation and transformer oil immediately surrounding the core. In addition, the noise of the transformer also increases.

At the same time, due to improper voltage selection, core saturation is caused in the 6-35kV neutral point non-effectively earthed system, which generates a sustained high amplitude ferromagnetic resonant overvoltage. The ferromagnetic resonance can be fundamental, higher order and sub-harmonics, but because the overvoltage frequency is often lower than the rated frequency, the core is highly saturated, causing the relative ground voltage to rise and the excitation current to increase further, thereby causing serious damage to the equipment. .

Why "Warring States Dispute"

There are many factors that cause the quality of transformer products in China, both technical and industrial. After analysis, there are currently five major industry reasons for the poor quality of transformer products and the low pass rate:

First, the market is over-competitive.

At present, the high-speed development of China's transformer market is in the "Warring States era," and large enterprises compete in the races. Small businesses are rolling over each other and their living conditions are poor. At the same time, foreign-funded enterprises are making every effort to enter China, and many multinational company executives have come to China to inspect. Under the background of the oversupply of transformers in the world, multinational corporations have already clamored for China's huge transformer market. Therefore, in the early 1990s, various multinational corporations came to China to look for opportunities. Since then, ABB, Siemens and others have all established joint ventures in China and have gained a lot of share in the transformer market. Today, the major cost advantage of China's transformer industry is gradually eroded, which has also contributed to the vicious competition among production companies. In order to increase market share and reduce production costs, some manufacturers have adopted methods to simplify production and reduce inspection procedures. Some of the small companies that have low prices as competitive products have to sacrifice the quality of products to achieve the goal of low prices. Enterprises use cutting-edge materials and even use unfair raw materials and other unfair methods to achieve the purpose of reducing costs, leading to a decline in product quality.

Second, excess capacity in the industry has caused disorderly market competition.

Due to the low threshold of low-end transformers, excess capacity has emerged in recent years. In industries with overcapacity, there have been frequent competitions among enterprises to compete for the market, and even there have been phenomena of counterfeiting, shoddying, and recharging. This has caused disorderly market competition. It is understood that the transformer market has seen the use of scrap materials used to dismantle old transformers to produce "new" transformers. These counterfeit and inferior products have serious safety hazards. Disordered market competition not only undermines the market economic order, but also seriously affects the healthy development of the industry.

Third, raw material prices fluctuate greatly and restrict the development of the industry.

As we all know, the main raw material for transformer production is silicon steel sheet, copper, and transformer oil. As the main raw material for transformers, silicon steel sheet and copper, domestic production is very limited and has been dependent on imports for a long period of time. In recent years, the prices of these raw materials have continued to soar, leading to a surge in product costs. In the face of soaring raw material prices, transformer manufacturers are in trouble, especially since large transformers have a long production cycle. General companies are trying to reduce capital occupation and reduce inventory (even claiming "zero" inventory) based on the requirements of modern management concepts. Therefore, there is a certain hysteresis interval from the acceptance of orders to the purchase of raw materials. In addition, due to material costs in the entire transformer costs The proportion in China reached 60% or even higher, and the impact of rising prices of raw materials on cost increases became even more pronounced. Therefore, according to the product prices quoted by the transformer manufacturers at the time of signing the contract at the raw material market price, it is impossible to avoid the “products have not yet been sold and losses have been formed” due to the mad increase in raw material prices during the period from order to delivery. One lost one situation. In the event that the price of the product is regulated and the price cannot be reasonably raised, the survival of the company and the development of the industry will be seriously threatened.

Fourth, the human cost is low and the industry automation level is low.

China is a big manufacturing country and has an important advantage of low labor costs. This provides favorable conditions for China's transformer industry to achieve rapid development in international industrial transfer, and it also brings about inertia to our country's enterprises. Due to the low labor cost in China, many companies are reluctant to invest capital and energy in technological innovation, and they are even less willing to adopt automated production on a large scale, which has hindered the quality of our transformer products. In recent years, the domestic transformer industry has greatly improved the variety, level, and high voltage transformer capacity of transformers by introducing advanced foreign technologies. However, there are still certain gaps in details. At present, domestic transformer manufacturing mainly relies on manual operation, which is an important factor in low labor productivity and unstable product quality. The main elbow factor in China's distribution transformer production is the degree of automation and process assurance of key equipment.

Fifth, the low-end competition is serious, the protection of intellectual property rights is insufficient, and investment in R&D is insufficient.

In recent years, China's transformer industry has developed rapidly, and the level of technology and technical capabilities have greatly improved. Both the progress and results of research and development can keep up with the international level. However, there are still problems with relatively low technological content, relatively weak technical foundation, insufficient protection of core competitiveness and intellectual property rights. Many domestic manufacturers are reluctant to invest a lot of effort in the development of core technologies. Some companies adopt simple and easy methods of copying and copying other people's technologies. Although this can greatly save the research period and effort, it is not conducive to the long-term development of China's transformer industry.

Enterprises must be honest First, the production companies should establish a high degree of legal awareness, the person in charge of the company is the first person responsible for quality. The quality problem is not only a matter of technicians, it depends to a large extent on the attitude of the person in charge of the company. Enterprises should have a sense of integrity and self-discipline and awareness of industry responsibility, strict quality control, against the pursuit of high profits and deviate from professional ethics; operating in accordance with the law, to ensure that the transformer product quality and promotion of the same, to ensure after-sales service quality, to win the power grid users satisfaction. As a company that has a sense of responsibility to the society, it should constantly improve its own quality concept. That is, quality is the life of the company, and the future of the company should not be fortunate for the benefit of the moment. When reducing the cost of products, it is necessary to create inexpensive products through technological improvements and innovations.

Secondly, the whole process of transformer production: iron core sheet cutting (partial companies have automatic cutting lines), winding, suits, insulation parts production, assembly, and so on... are all based on artificially strictly following the technical operating procedures. . Therefore, the quality of a transformer depends to a large extent on the skill level of the workers and the quality consciousness and business philosophy of the leaders. Only the awareness that quality is the life of a company can be carried out from marketing to production to service, and it can be implemented in every aspect. Only in this way can we produce products that meet quality standards in order to achieve customer satisfaction.

We also clearly know that material price fluctuations and fierce competition from many companies have caused great difficulties for the production and operation of enterprises. However, we hope that the more such a situation, the firmer the company's belief in establishing a factory by quality and gaining trust by quality. For users, the market is dominated by quality, and after the winter it is spring.

Once again, it is recommended that all manufacturers in the transformer industry respond positively to the call of the national energy-saving emission reduction policy, follow the development model of low-carbon economy, insist on independent innovation, improve the inefficient equipment and processes, and increase the R&D, production and promotion of energy-saving transformers. Promote technological upgrading of the industry; strengthen design capabilities and investment in scientific research; increase the protection of knowledge products; and upgrade automated production processes.

Finally, it is recommended that transformer companies conduct basic research, strengthen the winding stability process and the overall assembly of the transformer, improve the reliability of the product, and provide reliable parameters for the optimization calculation program to further reduce the cost of the transformer.

Users must save energy First, the National Development and Reform Commission's Order No. 9 of the year “Guidance Catalogue for the Adjustment of Industrial Structures (2011 Edition)” has been implemented since June 1, 2011. It is recommended to use rolling core transformers in the catalogue, and to eliminate high-loss transformers such as S7. . The second list of energy-saving electromechanical equipment (products) recommended by the Ministry of Industry and Information Technology recommended the S13 type three-dimensional coil core transformer. The use of high-efficiency energy-saving transformers to replace and replace transformers with low efficiency and backward power consumption has been included in the scope of financial support for the national financial energy-saving technological transformation financial incentive projects. It is recommended that all grid users should use advanced energy-saving transformers as a priority and resolutely eliminate high-energy-consuming backward transformers in order to provide the cleanest and most effective solution to ease the shortage of electricity supply.

Second, it is recommended that power grid companies, power supply departments, and consumer users should reasonably select parameters according to their own special requirements and consider capacity, voltage, impedance, and losses in a comprehensive manner. During the bidding process, it is not possible to consider prices alone. Need to consider quality and energy consumption issues.

Government supervision needs to be strengthened. First, strengthen the day-to-day management and supervision of transformer manufacturers, standardize competition order, and create a good atmosphere for competition. Promoting producers' operators to raise their awareness of law and quality, and to ensure good quality and avoid unqualified products from entering the market. Further improve the market competition mechanism, increase the supervision and punishment of enterprises producing counterfeit and shoddy products, strive to protect the lawful rights and interests of law-abiding companies, and make the “survival of the fittest” become the competition rules of the transformer industry.

Second, speed up the formulation of transformer product standards and effectively reduce resource consumption.

Third, strengthen the guidance of enterprises, guide enterprises in the production and operation of a correct understanding and implementation of standards, so that it is conducive to the development of enterprises and product quality. Only in this way can the healthy development of the transformer industry be promoted.

4. Correctly implement the policy orientation of inhibiting production capacity and redundant construction, study and establish a scientific and qualitative evaluation system for the qualitative and quantitative analysis of overcapacity in China, conduct scientific annual statistics on the production capacity indicators of enterprises, and promptly master and guide the growth of industrial production capacity, prevent and Suppresses the emergence of excess capacity and redundant construction problems; vigorously promotes the optimization and upgrading of the transformer industry, promotes industrial restructuring and resource integration, achieves product structural adjustment through technological innovation, and realizes corporate development grouping and supply package integration.

V. It is recommended that the government actively guide and support advantageous enterprises and introduce more preferential policies to encourage enterprises with core competitiveness to increase basic research and R&D investment, so as to enhance the company’s ability to independently innovate, compete in the international market, and support its advantages. Enterprises, to strengthen the degree of industry concentration, to promote the industry to accelerate the structural adjustment and change of development mode.