1.In photovoltaic systems, the device that converts direct current to alternating current is the inverter, which works based on power electronics technology and utilizes high efficiency switching devices Frequency switching converts direct current into alternating current, while achieving maximum power point tracking to improve power generation efficiency.
Detailed explanation: Inverters are key equipment in photovoltaic systems, which convert the direct current generated by photovoltaic panels into alternating current that meets the requirements of the grid or load. The maximum power point tracking (MPPT) function can keep the photovoltaic panels working near the maximum power point, improving power generation efficiency, as the output power of photovoltaic cells varies with factors such as light and temperature
2. Series connection of photovoltaic modules will increase voltage, while parallel connection will increase current. When designing a photovoltaic array, it is necessary to combine the number and connection method of modules reasonably according to the input voltage and current range of the inverter.
Detailed explanation: When photovoltaic modules are connected in series, the voltages of each module add up while the current remains unchanged; When connected in parallel, the currents of each component add up while the voltage remains unchanged. Inverters have certain range requirements for input voltage and current, so it is necessary to arrange the series and parallel connection of components to ensure the normal operation of the inverter and improve system efficiency.
3. The grounding of photovoltaic systems includes working grounding, protective grounding, and lightning protection grounding. Good grounding can ensure the safety of personnel and equipment, and prevent fault hazards such as lightning strikes and leakage.
Detailed explanation: Working grounding is to ensure the normal operation of the system, such as the neutral point grounding of the inverter; Protective grounding is the process of connecting the metal casing of equipment to the ground to prevent electric shock to personnel in the event of electrical leakage; Lightning protection grounding is the process of introducing lightning into the ground to prevent equipment from being damaged by lightning strikes.
4. The power factor of a photovoltaic power station reflects its utilization efficiency of electrical energy. By reasonably allocating reactive power compensation devices, the power factor can be improved and reactive power losses in the power grid can be reduced.
Detailed explanation: Power factor is an indicator of the efficiency of electrical equipment in utilizing electrical energy. A low power factor means that the equipment needs to absorb more reactive power from the grid, resulting in increased reactive power losses in the grid. The reactive power compensation device can provide or absorb reactive power, making the power factor close to 1 and improving the efficiency of electrical energy utilization.
5. The open circuit voltage of a photovoltaic cell refers to the output voltage of the cell under no-load conditions, and the short-circuit current refers to the output current of the cell under short-circuit conditions. They are important parameters for measuring the performance of a photovoltaic cell.
Detailed explanation: Open circuit voltage reflects the maximum voltage that a photovoltaic cell can output under ideal conditions, while short-circuit current reflects the maximum current that the cell can generate under illumination. These two parameters are influenced by factors such as light intensity and temperature, and are key indicators for evaluating the performance and quality of photovoltaic cells.
