Aluminum-core wire and cable, with aluminum as the core conductor, are widely used in power transmission and distribution systems.
Their key features include:
1. Lightweight and Economical: Aluminum's density is only approximately 30% of copper's, significantly reducing cable weight and lowering transportation and installation costs.
Aluminum's price is significantly lower than copper, offering significant material cost advantages and making it particularly suitable for large-section, long-distance lines.
2. Conductivity: Aluminum's conductivity is approximately 61% of copper's. To achieve a similar current-carrying capacity,
the cross-sectional area of an aluminum conductor must be approximately 1.6 times larger than that of copper.
3. Applications: Primarily used in fixed installations such as high-voltage/ultra-high-voltage overhead transmission lines (a core advantage),
medium- and low-voltage distribution networks, and main power supply systems for large buildings and factories.
4. Key Considerations
*High Connection Requirements: Aluminum is susceptible to oxidation, resulting in high contact resistance and heat generation at the connection.
Specialized copper-aluminum transition terminals, anti-oxidation compound grease, and rigorous processing techniques are essential to prevent loosening and failure.
*Mechanical Strength: Pure aluminum has lower tensile strength and creep resistance than copper, requiring greater care during connection and bending.
Specially treated aluminum alloys can improve this property.
1. Power Transmission System
Overhead Transmission Lines (Core Scenario):
High-voltage/Ultra-high-voltage Transmission (110kV-1000kV): Pure aluminum stranded wire (such as JL/G1A) accounts for over 90% of overhead lines due to its lightweight (reducing tower load) and low cost.
Medium- and Low-voltage Distribution (1kV-35kV): Insulated aluminum cables (such as JKLYJ) are used in urban and rural power grids. They are UV-resistant and suitable for outdoor installation.
2. Industrial and Building Power Supply
-Large Facility Trunk Lines:
Factories, shopping malls, and data centers: Armored aluminum alloy cables (such as YJHLV22) are installed directly in burial or in conduit. They carry high currents (e.g., 240mm² carrying 425A) and are 40% less expensive than copper cables.
-Outdoor Fixed Wiring:
Streetlights and temporary construction sites: BLVV aluminum cables (double-layer PVC sheath) are weather-resistant, economical, and durable.