Most PV modules are installed in fixed installations. The fixed operation mode of photovoltaic array is to install photovoltaic modules on fixed structural parts. The photovoltaic array faces the equator at a certain installation angle, and converts light energy into electrical energy after receiving the radiation of the sun. Its advantages are that the civil work is small, the installation is simple, it is strong and reliable, the operation and maintenance are convenient and simple, the unit power/generating capacity occupies a small area, and the unit peak power investment is small, especially suitable for harsh climate environments such as deserts. The disadvantage of fixed photovoltaic is that the solar energy cannot be fully utilized, and the power generation per unit peak power is small.
According to the different inclination angle settings, the fixed type can be divided into the optimal inclination fixed type and the artificial inclination adjustable fixed type.
The optimal inclination fixed type takes the maximum cumulative radiation amount throughout the year as the goal, and calculates the local optimal installation inclination in advance according to the local geographical environment, climate and other conditions. All arrays use this inclination for fixed installation. Generally, it will not be adjusted again, and it is the most widely used operation mode at present.
The artificial inclination adjustable fixed type is developed on the basis of the optimal inclination fixed type. It refers to dividing the annual sunshine time into several segments according to the annual illumination conditions of the location of the photovoltaic power station, and calculating each time segment separately. The optimal inclination angle of the photovoltaic module is adjusted for a limited number of times according to the optimal inclination angle of each time period. After each angle adjustment, the bracket is fixed by its own connector, which is a variation of the optimal inclination angle fixed type. . Compared with the optimal inclination fixed type, this method can increase a certain amount of power generation. Compared with the tracking bracket, the manual inclination adjustable fixed type has lower costs and later maintenance costs. The artificial inclination adjustable fixed bracket structure is appropriately improved on the basis of the optimal inclination fixed type. The structure is relatively simple, the stability is good, and the advantages of the optimal inclination fixed type and the tracking bracket are taken into account. The adjustment range of the bracket is generally from -60° to 60°, which can be adjusted manually, and some products can also be adjusted automatically through the control device.
Fixed adjustable type is divided into jack type, hydraulic rod type, push rod type and arc type. The first two forms require the installation of jacks or hydraulic equipment, which increases equipment investment; the latter two only change the connection form of the bracket, and the cost increase is not obvious.
The jack-type fixed adjustable bracket can adjust the angle of the bracket through the jack connected between the inclined beam and the vertical rod of the bracket. After the angle is adjusted, the bracket is fixed by the self-locking of the jack. The characteristics of this type of bracket are: easy installation, the installation method is basically the same as that of the fixed bracket; low coaxiality requirements, through the design of the universal joint connecting rod, do not require multiple support points to be concentric; easy to adjust, not limited by weather conditions, only One person is required to adjust; the handle is quickly locked without tightening bolts, and the adjustment time is short; the operation and maintenance cost is low; the civil construction cost is low, and the basic requirements are not higher than the standard of the fixed bracket; the angle can be adjusted continuously;
The hydraulic rod-type fixed adjustable support adjusts the height of the hydraulic rod through hydraulic equipment, and then adjusts the angle of the support.
The push-rod-type fixed adjustable bracket utilizes the diagonal strut of the bracket to push and pull back and forth in the slot of the horizontal rod at the bottom of the foundation to realize the angle adjustment of the photovoltaic bracket. After the angle is adjusted, it is fixed with bolts.
The arc type fixed adjustable bracket uses the hinged connection between the bracket inclined beam and the vertical rod to adjust the angle of the photovoltaic bracket. After the angle is adjusted, the arc strut and the vertical rod are fixed by bolts.