Growatt On Grid Inverter

Growatt solar inverters only generate active power under normal power generation conditions. However, in actual application scenarios, especially in industrial and commercial solar self-use scenarios, the power consumed by the load includes not only active power, but also reactive power. The power grid company accounts for this in the electricity bill. Only active electricity fees will be charged during settlement, but the power factor will be assessed at the same time. If the power factor is lower than the requirements of the power grid company, the power grid company will charge a punitive power adjustment fee. In order to avoid the cost of power regulation, industrial and commercial owners usually install reactive power compensation devices at the load end to ensure that the power factor reaches the standard.

The PID (Potential Induced Degradation) effect of solar panels refers to a situation where the performance of the module will gradually decay after working for a long time. The direct harm of the PID effect is that a large amount of charge accumulates on the surface of the battery, causing passivation on the surface of the battery, which reduces the fill factor (FF), open circuit voltage, and short circuit current of the battery component. Reduce the output power of the solar power station, reduce the power generation, and reduce the income of the solar power station.
The PID effect easily occurs in humid environments, and the activity level is positively related to the degree of humidity. At the same time, the degree of contamination of the component surface by conductive, acidic, alkaline, and ion-containing objects is also related to the occurrence of attenuation phenomena.
At present, the mainstream components themselves have the function of preventing PID effect. In addition, the inverter can also add this function. By raising the N line voltage on the AC output side, the PV negative electrode voltage is indirectly raised, so that the PV negative electrode of each inverter to the ground voltage is close to 0 or slightly higher than 0 potential to achieve the purpose of suppressing the PID effect. The data collector in the system connects and communicates with the inverter and the external anti-PID module, automatically collects the negative pole status information of the inverter, and automatically performs lifting adjustment, thereby realizing the intelligent anti-PID function.

Heat dissipation is an important issue for inverters. Thousands of power electronic components are integrated into an inverter. If heat dissipation is poor, the output capability and service life of the inverter will be seriously affected. The 10-degree rule for electronic devices means that for every 10°C increase in temperature, the life of the device will be reduced by half. At present, inverters generally use intelligent air cooling. The inverter has an external high-performance fan and a protection level of up to IP67. The built-in temperature sensor and drive circuit monitor the device temperature in real time and set appropriate thresholds. When it is detected that the temperature exceeds the threshold, the circuit automatically drives the fan to run. After the temperature returns to normal, the drive circuit is turned off and the fan gradually stops running.

The reason why the Growatt inverter can realize automatic operation is because it has the function of intelligent restoration and grid connection. The normal operation of a power station depends on many factors, such as string voltage, grid voltage, frequency, etc. The inverter may appear in standby, fault shutdown, etc. states due to insufficient grid-connected output conditions. Once it detects that all operating conditions are normal, it will automatically resume grid-connected output after a self-check (generally 20s~5min), eliminating the need for re-debugging, restarting and other human operations.