Photovoltaic power matrix installation in the technical aspects need to pay attention to points (|)
Solar photovoltaic bracket ground matrix in the technical aspects need to pay attention to two points.
1. is the wind resistance to the requirements of the bracket.
2, is the distance between the bracket matrix and bracket matrix.
To ensure wind resistance, the bracket mostly uses aluminum alloy and steel structure mixed, so that the skills to ensure that the bracket wind resistance, will not cause the solar bracket is not firmly fixed hidden dangers, but also to ensure the overall appearance of the bracket.
The grid-connected inverter is an inverter power supply used in the field of solar photovoltaic power generation. The grid-connected inverter transforms the alternating current generated by the solar panel into alternating current that can be directly allocated to the grid through power electronic conversion technology. It is an essential key component in the photovoltaic power generation system. So what is the role of grid-connected PV inverter? What is the working principle?
A, the role of grid-connected photovoltaic inverter
Inverter not only has the function of straight AC conversion, but also has the function of maximizing the performance of solar cells and system fault protection function. In summary, there are automatic operation and shutdown function, high-power tracking control function, anti-unit operation function (for grid-connected system), automatic voltage adjustment function (for grid-connected system), DC detection function (for grid-connected system), DC grounding detection function (for grid-connected system).
1、Automatic operation and shutdown function
After the sun rises in the morning, the intensity of solar radiation gradually increases, and the output of solar cell also follows, and when the output power required for inverter work is reached, the inverter starts to run automatically. After entering operation, the inverter will monitor the output of the solar cell module all the time. As long as the output power of the solar cell module is greater than the output power required for the inverter to work, the inverter will continue to run; until the sunset shutdown, the inverter can run even on rainy days. When the output of the solar cell module becomes smaller and the inverter output is close to 0, the inverter will form a standby state.
2、High power tracking control function
The output of the solar cell module varies with the intensity of solar radiation and the temperature of the solar cell module itself (chip temperature). In addition, because the solar cell module has the characteristic of voltage decreasing with current, there is a good working point to obtain high power. The solar radiation intensity is changing, and obviously the good operating point is also changing. In relation to these changes, the system always obtains high power output from the solar cell module by keeping the operating point of the solar cell module at the high power point, and this control is called high power tracking control. The big feature of the inverter for solar power system is the inclusion of high-power point tracking (MPPT) this function.
3, grid detection and grid-connected functions
Before grid-connected inverters are connected to the grid to generate electricity, they need to take power from the grid, detect the voltage, frequency, phase sequence and other parameters of the grid feed, and then adjust their own parameters of power generation, synchronize with the grid electrical parameters, and only after completion will they be connected to the grid to generate electricity.
4、Zero (low) voltage ride-through function
When a power system accident or disturbance causes a voltage transient drop in the grid connection voltage of the PV power station, within a certain voltage drop range and time interval, the PV power station can ensure continuous operation without going off-grid.
5, the detection and control of islanding effect
In normal power generation, the PV grid-connected power generation system is connected to the grid and delivers active power to the grid, but when the grid loses power, the PV grid-connected power generation system may still work continuously and be in stand-alone operation with the local load, a phenomenon known as the islanding effect. This phenomenon is called islanding effect. When the islanding effect occurs in the inverter, it will cause big safety hazards to personal safety, grid operation, and the inverter itself, so the standard for grid-connected inverter stipulates that the PV grid-connected inverter must have the detection and control function of islanding effect.
