Photovoltaic cables are single-core flexible cables designed for solar power distribution systems. Photovoltaic cable can bear super mechanical load, with good wear resistance, high temperature resistance, weather resistance characteristics, with a long service life. Based on the discovery of insulating material technology, some small wire diameter cables can also have the same superior characteristics. The following Xiaobian will take you to understand the economic choice of solar cable price.
Because the photovoltaic cable is relatively long, the line loss is relatively large, then you can consider using the line through the large photovoltaic cable to reduce the loss, because the larger the photovoltaic cable, the less internal resistance. But also consider the price of photovoltaic cable, inverter AC output sealing terminal diameter. In the photovoltaic system, the temperature of the photovoltaic cable is different due to the different environment in which the line is installed. The voltage drop on the PV cable is different due to the different distance between the inverter and the connection point.
In the design and selection of photovoltaic cable, the technical parameters such as rated load flow, voltage and temperature of photovoltaic cable are mainly considered, and the outer diameter, bending radius and fire prevention of the cable are still considered when installing, and the price of photovoltaic cable is considered when calculating the cost.
For example, a 20kW power station, the total length of three cables from the inverter to the connection point is 100 meters, the average day sunshine time is 4 hours, the output current is 32A, the output cable can be selected 4mm, 6mm and 10mm, 16mm.
4 square cable total internal resistance 0.46 ohm, the market price is 3.5 yuan/meter; 6 square cable total internal resistance 0.31 ohms, the market price is 4.8 yuan/meter; the total internal resistance of 10 square cables is 0.18 ohms, the market price is 9.5 yuan/meter; 16 square cable total internal resistance 0.115 ohm, the market price is 13.5 yuan/meter.
1. Choose 4 square cables, the loss of one day is I²Rt= (302*0.46*4) /1000=1.656 degrees, about 600 degrees of electricity a year, according to the cost of 0.75 yuan per hour, a year loss of 450 yuan;
2. Choose 6 square cables, the loss of one day is I²Rt= (302*0.31*4) /1000=1.116 degrees, about 400 KWH of electricity a year, according to the cost of 0.75 yuan per KWH, a loss of 300 yuan;
3. Choose 10 square cables, the loss of a day is I²Rt= (302*0.18*4) /1000=0.65 degrees, about 240 degrees of electricity a year, according to the cost of 0.75 yuan per hour, a year loss of 180 yuan;
4. Choose 16 square cables, the loss of one day is I²Rt= (302*0.115*4) /1000=0.414 degrees, about 150 degrees of electricity a year, according to the cost of 0.75 yuan per hour, a year loss of 110 yuan.