Before the inverter is commissioned, the following conditions should be met: ① The inverter control power supply should meet the conditions for input. ② The DC side cables of the inverter should be connected firmly, with correct polarity and good insulation. ③ The cables on the AC side of the inverter should be wired firmly, the phase sequence should be correct, and the insulation should be good. ④The wiring of the square array is correct, and it has the conditions to provide DC power to the inverter.
Before commissioning the inverter, the following inspections should be done: ① The grounding of the inverter should meet the requirements. ②The internal components of the inverter should be in good condition, and there should be no signs of damp or discharge. ③ All cable connection bolts, plug-ins and terminals inside the inverter should be firmly connected and not loose. ④If the inverter body is equipped with a manual switching device, its operation should be flexible and reliable, with good contact, and the switch position indication is correct. ⑤ The temporary identification of the inverter should be clear and accurate. ⑥ There should be no debris inside the inverter, and it should be cleaned.
The debugging of the inverter should meet the following requirements: ① The debugging of the inverter should be carried out with the cooperation of the manufacturer. ②When the inverter control circuit is electrified, it should be checked as follows: a. The working status indicator and the display of the man-machine interface should be normal. b The parameter settings on the man-machine interface should be correct. c. The cooling device should work normally.
When the DC side of the inverter is charged and the AC side is not charged, the following work should be performed: ① The deviation between the measured DC side voltage value and the value displayed on the man-machine interface should be within the allowable range. ②Check that the impedance value of the DC side to ground displayed on the man-machine interface should meet the requirements.
When the DC side of the inverter is charged and the AC side is charged, and the grid-connected conditions are met, the following work should be performed: ①The deviation between the measured AC side voltage value and the value displayed on the man-machine interface should be within the allowable range; the AC side voltage and frequency should be within the rated range of the inverter, and the phase sequence should be correct. ② For inverters with door limit locking function, when the inverter panel door is open, the grid connection action should not be performed.
After the inverter is connected to the grid, the inverter should be tripped and de-loaded under the following test conditions: ① For inverters with door limit locking function, open the inverter panel door. ②The inverter grid side loses power. ③ The impedance to ground on the DC side of the inverter is higher than the protection setting value. ④ The DC input voltage of the inverter is higher or lower than the threshold value set by the inverter. ⑤ Inverter DC input overcurrent. ⑥ The voltage on the line side of the inverter deviates from the allowable range of the rated voltage. ⑦Inverter line frequency exceeding the rated frequency should be within the allowable range. ⑧ The current imbalance on the AC side of the inverter exceeds the setting range.
The test work such as the operation efficiency, anti-islanding protection and output power quality of the inverter should be tested by a qualified unit. When debugging the inverter, you should also pay attention to the following points: ①After the inverter is running, when the panel door needs to be opened for inspection, it must be confirmed that no voltage remains before the operation is allowed. ②When the inverter is running, it is strictly forbidden to disconnect the main switch or fuse of the combiner box without arc breaking capability. ③ If you need to touch the live parts of the inverter, you must cut off the DC side and AC side power and control power.
It is strictly forbidden for construction personnel to test the inverter alone.
The monitoring function debugging of the inverter should meet the following requirements: ① The communication address of the monitoring system should be correct, with good communication and anti-interference ability. ②The monitoring system should accurately reflect the inverter’s operating status, data and various fault information in real time. ③ The inverter with the functions of remote start, stop and adjustment of active power output should respond to remote operation in real time, and the action is accurate and reliable.