Views: 31 Author: Site Editor Publish Time: 2023-11-01 Origin: Site
In the world of renewable energy systems, the hybrid inverter stands as a central hub, orchestrating the intricate dance between solar power generation, battery storage, and grid connectivity. However, navigating the sea of technical parameters and data points that accompany these sophisticated devices can often seem like deciphering an enigmatic code for the uninitiated. As the demand for clean energy solutions continues to surge, the ability to grasp and interpret the essential parameters of a hybrid inverter has become an indispensable skill for both seasoned energy professionals and enthusiastic eco-conscious homeowners alike.
Unlocking the secrets held within the labyrinth of inverter parameters not only empowers users to monitor and optimize their energy systems but also serves as a gateway to maximizing energy efficiency and harnessing the full potential of renewable energy resources. In this comprehensive guide, we embark on a journey to demystify the complexities of reading the parameters of a hybrid inverter, equipping readers with the tools and knowledge needed to effortlessly navigate the intricacies of their sustainable energy infrastructure.
(I) Maximum allowable access to the PV string power
Maximum allowable access to the PV string power is the maximum DC power allowed by the inverter to connect to the PV string.
(ii) Rated DC power
The rated DC power is calculated by dividing the rated AC output power by the conversion efficiency and adding a certain margin.
(iii) Maximum DC voltage
The maximum voltage of the connected PV string is less than the maximum DC input voltage of the inverter, taking into account the temperature coefficient.
(iv) MPPT voltage range
The MPPT voltage of the PV string considering the temperature coefficient should be within the MPPT tracking range of the inverter. A wider MPPT voltage range can realize more power generation.
(v) Starting voltage
The hybrid inverter starts when the start voltage threshold is exceeded and shuts down when it falls below the start voltage threshold.
(vi) Maximum DC current
When selecting a hybrid inverter, the maximum DC current parameter should be emphasized, especially when connecting thin film PV modules, to ensure that each MPPT access to the PV string current is less than the maximum DC current of the hybrid inverter.
(VII) Number of input channels and MPPT channels
The number of input channels of the hybrid inverter refers to the number of DC input channels, while the number of MPPT channels refers to the number of maximum power point tracking, the number of input channels of the hybrid inverter is not equal to the number of MPPT channels.
If the hybrid inverter has 6 DC inputs, each of the three hybrid inverter inputs is used as a MPPT input. 1 road MPPT under the several PV group inputs need to be equal, and the PV string inputs under different road MPPT can be unequal.
(i) Maximum AC power
Maximum AC power refers to the maximum power that can be issued by the hybrid inverter. Generally speaking, the hybrid inverter is named according to the AC output power, but there are also named according to the rated power of DC input.
(ii) Maximum AC current
Maximum AC current is the maximum current that can be issued by the hybrid inverter, which directly determines the cross-sectional area of the cable and the parameter specifications of the power distribution equipment. Generally speaking, the specification of the circuit breaker should be selected to 1.25 times of the maximum AC current.
(iii) Rated output
Rated output has two kinds of frequency output and voltage output. In China, the frequency output is generally 50Hz, and the deviation should be within +1% under normal working conditions. Voltage output has 220V, 230V, 240V, split phase 120/240 and so on.
(D) power factor
In an AC circuit, the cosine of the phase difference (Φ) between the voltage and the current is called the power factor, which is expressed by the symbol cosΦ. Numerically, the power factor is the ratio of active power to apparent power, i.e., cosΦ=P/S. The power factor of resistive loads such as incandescent bulbs and resistance stoves is 1, and the power factor of circuits with inductive loads is less than 1.
There are four types of efficiency in common use: maximum efficiency, European efficiency, MPPT efficiency and whole machine efficiency.
(I) Maximum efficiency: refers to the maximum conversion efficiency of the hybrid inverter in the instantaneous.
(ii) European efficiency: It is the weights of different power points derived from different DC input power points, such as 5%, 10%, 15%, 25%, 30%, 50% and 100%, according to the light conditions in Europe, which are used to estimate the overall efficiency of the hybird inverter.
(iii) MPPT efficiency: It is the accuracy of tracking the maximum power point of the hybrid inverter.
(iv) Overall efficiency: is the product of European efficiency and MPPT efficiency at a certain DC voltage.
(I) Voltage range
Voltage range usually refers to the acceptable or recommended voltage range within which the battery system should be operated for optimum performance and service life.
(ii) Maximum charge/discharge current
Larger current input/output saves charging time and ensures that the battery is full or discharged in a short period of time.
(i) Islanding protection
When the grid is out of voltage, the PV power generation system still maintains the condition of continuing to supply power to a certain part of the line of the out-of-voltage grid. The so-called islanding protection is to prevent this unplanned islanding effect from occurring, to ensure the personal safety of the grid operator and the user, and to reduce the occurrence of faults of the distribution equipment and loads.
(ii) Input overvoltage protection
Input overvoltage protection, i.e., when the DC input side voltage is higher than the maximum DC square access voltage allowed for the hybrid inverter, the hybrid inverter shall not start or stop.
(iii) Output side overvoltage/undervoltage protection
Output side overvoltage/undervoltage protection means that the hybrid inverter shall start the protection state when the voltage on the output side of the inverter is higher than the maximum value of output voltage allowed by the inverter or lower than the minimum value of output voltage allowed by the inverter. The response time of abnormal voltage on the AC side of the inverter should be in accordance with the specific provisions of the grid-connected standard.
With the ability to understand hybrid inverter specification parameters, solar dealers and installers, as well as users, can effortlessly decipher voltage ranges, load capacities, and efficiency ratings in order to realize the full potential of hybrid inverter systems, optimize energy use, and contribute to a more sustainable and environmentally friendly future.
In the dynamic landscape of renewable energy, the ability to comprehend and leverage the parameters of a hybrid inverter serves as a cornerstone for fostering a culture of energy efficiency and environmental stewardship. By embracing the insights shared in this guide, users can confidently navigate the complexities of their energy systems, making informed decisions and embracing a more sustainable and resilient approach to energy consumption.