In photovoltaic grid-tied inverters, there is a strange parameter, that is, the input starting voltage of the inverters, which is about 30V higher than the minimum operating voltage. For example, single-phase inverters, MPPT operating voltage is 70V to 550V, starting voltage is 100V. Many people wonder whether the inverters work or not from 70V to 100V. If it is working, but the inverters need 100V to start. How does the inverters work without starting?

In fact, the starting voltage is higher than the minimum operating voltage, which is designed according to the characteristics of photovoltaic modules. Before the start of the inverters, the components are not working, open circuit, and the voltage will be relatively high. When the inverters are started, the components will be working and the voltage will be reduced. In order to prevent the inverters from starting again and again, the starting voltage of the inverters is higher than the minimum operating voltage.

If three components are connected in series, when the sun shines in the morning, the open-circuit voltage may be 90V. If it starts at this time, it may only be 60V. If it does not reach the working voltage, the inverters will stop. Only when the open-circuit voltage exceeds 100V, if it starts at this time, the working voltage will exceed 70V, the inverters will work all the time.

After the inverters start, it does not mean that the inverters will have power output immediately. The control part, CPU and screen of the inverter work first. First of all, the inverters are self-checked, then the components and the power grid are detected. After no problem, the output of the inverters will only be achieved when the photovoltaic power exceeds the standby power of the inverters.