Cavo UHV
UHV; The voltage symbol is U (some places are useful for V); The unit of voltage is the volt, and the unit symbol is also V; Larger than the volt has kV (thousand volts), smaller than the volt mV (millivolts), uV (microvolts), and between them is the kilocare. In China, UHV refers to the voltage level of ±800 kV and above direct current and 1000 kV and above alternating current. Our country's voltage levels are generally divided into low voltage, medium voltage, high voltage, ultra-high voltage, UHV five categories. Uhv is the most advanced transmission technology in the world.
In China, UHV refers to ±1000Kv and above AC and ±800Kv and above DC transmission constitute UHV, UHV is generally used in the west-east power transmission and other ultra-long distance transmission voltage channels. Uhv is one of the few major independent innovation achievements in China and the world's leading. Uhv cable usually refers to the transmission of 35-1000KV power cable, it is a kind of long-distance transmission of electrical energy technical objects, it has a lot of advantages.
In the field of power transmission, UHV cable belongs to the existence of high-tech content, if it is not, then the entire infrastructure field will be affected. Uhv cables can carry out continuous transmission, for example, in some remote places, through UHV cables, it can meet the basic power supply needs, and can ensure stability. At the same time, it also has higher economic benefits because of lower cost and lower power loss.
Simply put, it is a cable capable of high-voltage power transmission. Nowadays, it may be used in infrastructure, industrial parks and other places, so its use is very wide and closely related to our lives.
Advantage
Uhv cable is an ultra-long distance transmission technology, which has many advantages such as long transmission distance, large capacity, high efficiency, low loss, low unit cost, and small footprint, and can effectively solve the ultra-long distance and ultra-large scale transmission of energy. In summary, it is very large power, ultra-long distance power supply, and the loss can be reduced to very low. It can effectively solve many problems, and the installation cost will be higher, but UHV is prominent in the seven areas of new infrastructure in the country in 2020, which shows that the construction of UHV is still imperative.
Uhv transmission modes can be divided into DC transmission and AC transmission according to different usage scenarios. Dc power transmission refers to only point-to-point transmission, the middle can not be dropped, the transmission power is large, the distance is far, suitable for long-distance transmission. Ac power transmission refers to the middle of the power grid can be formed, the transmission capacity is large, the coverage is wide, the line has a series, a network structure, can have both transmission and networking functions, suitable for short distance transmission. Because in the UHV within about 800 kilometers is more cost-effective AC, more than 800 kilometers of direct current is cheaper, so the distance is close to the AC transmission, once across the province and other ultra-long distance, DC transmission is more cost-effective and safe.
NO.1, Jiangnan Cable dispone di tecnologie e attrezzature di produzione avanzate. Dalla produzione dei conduttori alla lavorazione degli isolamenti, delle schermature e delle guaine, ogni passaggio è preciso e rigoroso per garantire l'alta qualità dei cavi di media tensione.
NO.2, il controllo di qualità è estremamente rigoroso. L'azienda ha istituito un perfetto sistema di controllo qualità, dalla selezione delle materie prime ai prodotti finiti che lasciano la fabbrica, controllando ad ogni livello. Ogni cavo di media tensione deve essere sottoposto a una serie di test rigorosi per garantire che i prodotti soddisfino o addirittura superino gli standard nazionali.
NO.3, Jiangnan Cable ha investito molto nella ricerca e nello sviluppo. In base alla domanda del mercato e alle esigenze particolari dei clienti, possiamo sviluppare cavi di media tensione con caratteristiche diverse, come una migliore resistenza ambientale e una migliore capacità di trasporto di corrente. Inoltre, la ricca linea di prodotti può soddisfare le diverse esigenze di vari progetti complessi e fornire ai clienti soluzioni di cavi complete.
I nostri casi
Quello che abbiamo finito
| Personalizzato | Specifiche del cavo | Materiale isolante | Costruzione dello scudo | Materiale della guaina | Struttura dell'armatura | Prestazione speciale | Lunghezza | ||||||||
| Sezione trasversale del conduttore | Numero di core | tipo di materiale | Spessore dell'isolamento | Tipo di schermatura | Numero di strati di schermatura | Selezione del materiale | Identificazione del colore | Tipo di armatura | Strati di armatura | Resistenza al fuoco | Prestazioni impermeabili | Prestazioni ignifughe | Resistenza al freddo | Campione di richiesta personalizzazione contatori | |
& Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | & Radico; | ||
Uhvdc transmission has the capability of point-to-point, ultra-long distance and large-capacity power transmission, which is mainly located in the ultra-long distance and ultra-large capacity of the large hydropower base in southwest China and the large coal power base in northwest China.
Uhvdc has a broad application prospect in China. The Wudongde and Baihetan hydropower stations of the second phase of the Jinsha River will also be sent out with 3 ±800 kV and 6.4 million kW DC UHV. The development of UHVDC transmission also provides an economic transmission mode for China's backup energy base of Tibet hydropower and Xinjiang coal power development, and provides technical support for strengthening electric power cooperation with Russia, Mongolia, Kazakhstan and other countries.
Uhv transmission technology has several significant advantages:
(1) High transmission capacity: UHV transmission technology can achieve higher transmission capacity at the same transmission distance, which is conducive to the scheduling and utilization of large-scale power resources.
(2) Long-distance transmission capacity: UHV transmission technology can achieve long-distance power transmission, helping to solve the problem of power transmission between resource-rich areas and areas with concentrated demand.
(3) Low line loss: By increasing the transmission voltage and using high-performance wire materials, UHV transmission technology can reduce line losses and improve power transmission efficiency.
(4) Saving investment costs: Because UHV transmission technology has a high transmission capacity and long-distance transmission capacity, the number of transmission lines can be reduced, thereby reducing investment cost.
Uhv transmission technology has several significant advantages:
(5)Reduce land resource occupation: UHV transmission technology can achieve higher transmission capacity and long-distance transmission capacity, thereby reducing the number of transmission lines and reducing land resource occupation.
Compared with ±600 kV and UHVDC below 600 kV, the main technical and economic advantages of UHVDC transmission can be summarized in the following six aspects:
1. Large conveying capacity. Using the 4000 amp thyristor valve, the ±800 kV DC UHV transmission capacity can reach 6.4 million kilowatts, which is 2.1 times of the ±500 kV and 3 million kW HVDC mode, and 1.7 times of the ±600 kV and 3.8 million kW HVDC mode, which can give full play to the advantages of large-scale transmission.
2. Long transmission distance. The adoption of ±800 kV DC transmission technology makes it possible to transmit electricity over a long distance, and the economic transmission distance can reach 2500 kilometers or even farther, providing transmission guarantee for the development of large hydropower bases in Southwest China.
3. Low line loss. In the case of the total cross section of the wire and the transmission capacity are the same, the resistance loss of the ±800 kV DC line is 39% of the ±500 kV DC line, and 60% of the ±600 kV DC line, improving transmission efficiency and saving operating costs.
4. Project investment province. According to the calculation of the relevant design department, for the ultra-long distance and ultra-large capacity transmission needs, the comprehensive cost per unit transmission capacity of the ±800 kV DC transmission scheme is about 72% of the ±500 kV DC transmission scheme, saving engineering investment benefits are significant.
5. The corridor utilization rate is high. The line corridor of ±800 kV and 6.4 million kW DC transmission scheme is 76 meters, and the transmission capacity per unit corridor width is 84,000 kW/meter, which is about 1.3 times that of ±500 kV and 3 million kW schemes and ±620 kV and 3.8 million kW schemes, improving the utilization efficiency of transmission corridors and saving precious land resources. Due to the large transmission capacity of the single circuit, the limited resources of the valley and river crossing points are significantly saved.
6.Flexible operation mode. The UHVDC transmission of State Grid Corporation intends to adopt the connection scheme of 400+400 kV double-twelve ripple converter in series, which has flexible operation mode and greatly improves system reliability. If any of the converter valve modules fails, the system can still guarantee 75% of the rated power output.
Uhv itself has the characteristics of large transmission capacity, long transmission distance, low energy consumption, small footprint, and obvious economy, especially the long transmission distance is its biggest feature. Due to the uneven distribution of power resources and load, more than 80% of energy resources in China are distributed in the west and north; More than 70% of the electricity consumption is concentrated in the east and central, the distance between supply and demand is about 800-3000km, due to the backward economy of the resource-rich area, the population is relatively sparse, the electricity generated in those areas can not be fully absorbed, and the power resources are not easy to store, if there is no way to strongly transport out, the resources will be wasted. However, in the face of such large-scale long-distance transmission, if the ultra-high voltage level transmission line loss, system stability and short circuit current problems will be very serious, so UHV transmission should be used to solve such problems.
As an efficient and economical means of power transmission, UHV transmission technology has been widely used in the world. With the advancement of science and technology and the advancement of global energy transition, UHV transmission technology will continue to play an important role in helping the world achieve sustainable development and low-carbon economy goals. However, in the face of many challenges, relevant parties need to strengthen technological innovation, optimize management measures and strengthen international cooperation and other efforts to promote the sustainable development of UHV transmission technology.
