How to choose the pv power generation system of cable?

In the entire solar system, although cable cost ratio is not high, but, as a 'blood vessels' photovoltaic system, the connection components, inverter, power distribution box and the important role of the grid, to the operation safety of the whole system, is stable and efficient, even electric

in the entire solar system, while the cost of the cable ratio is not high, but the cable as the 'blood' of photovoltaic system, the connection components, inverter, distribution box and the power grid plays an important role, for the running of the whole system security, stability and efficiency, and even had important effect on the overall profitability of power station. As a result, photovoltaic cable selection are the key in the process of system design. To pv cable type: according to different functions, photovoltaic (pv) system in the cable can be divided into two types: DC cable and communication cable. Dc cable ( 1) The serial cable between components. ( 2) Between different groups and group and DC power distribution box ( Mother's head) The parallel between the cable. ( 3) DC power distribution box and cable between the inverter. Above cable for DC cable, outdoor installation frequency is higher, in some special circumstances need to moisture, sun protection, cold resistant, heat resistant, uv protection, resistance to acid and alkali chemicals. Communication cable ( 1) From the inverter to the step-up transformer connection cable. ( 2) From the step-up transformer to the connecting cable of power supply system. ( 3) Cable connected to the power distribution equipment and power grid or users. This part of the cable, cable for ac load more equipped in the indoor environment, can undertake choosing according to the requirement of the general power cable selection. Pv cable photovoltaic power station in a large number of DC cable need to be laid in outdoor, poor environmental conditions. Cable material should be based on uv resistant, resistant to ozone, rapid changes in temperature and chemical corrosion conditions. In this environment, use for a long time made of ordinary materials of cable will cause cable sheath is fragile, and even will break down the cable insulation. These conditions will directly damage the cable system, and increase the risk of cable short circuit. Longer term, the possibility of a fire or personal injury is higher also, greatly influences the service life of the system. Therefore, in the photovoltaic power station using special photovoltaic cable and components is very necessary. Photovoltaic cable and special components not only has the best weather resistance, resistance to ultraviolet ray and ozone erosion resistance, can also withstand a wider range of temperature change. Cable design and selection principles of ( 1) The withstand voltage of the cable should be greater than the system of high voltage. For example, for 380 FuShu communication cable, should choose 450/750 v cables. ( 2) For arrays of photovoltaic array and the connection between the, selected the rated current of the cable is a cable in the calculation of maximum continuous current of 1. 56 times. ( 3) For ac load connection, selected the rated current of the cable is a cable in calculating the maximum continuous current of 1. 25 times. ( 4) For inverter connection, selected the rated current of the cable is a cable in the calculation of maximum continuous current of 1. 25 times. ( 5) Considering the influence of temperature on the cable performance. The higher the temperature, the smaller the carrying capacity of the cable. Cable should be installed in the ventilation and heat dissipation place as soon as possible. ( 6) , considering the voltage drop should not exceed 2%. Because of various unfavorable factors in the operation of the DC circuit in ground, often make the normal operation of the system. Extrusion, cable manufacturing, insulation materials, for example, is unqualified, insulation performance is low, the DC system insulation aging or some damage defects may result in grounding or become a hidden danger. In addition, the invasion of outside environment of small and medium-sized animals or tear can also cause DC ground fault. Therefore, in this case, usually with function of rat armoured cable sheath.