What is the difference between a photovoltaic inverter and an energy storage inverter?

In the field of new energy, photovoltaic inverters and energy storage inverters are both important devices, and they play an indispensable role in our lives. But what is the difference between the two? We will conduct an in-depth analysis of the two inverters from the aspects of structure, function, application scenarios, etc.

01

Structural differences

First of all, in principle, an inverter is mainly a device that converts DC power into AC power. It uses the switching characteristics of semiconductor devices (such as field effect transistors or thyristors, etc.) to control the power supply voltage and current through rapid switching, thereby achieving the conversion of DC to AC.

Photovoltaic inverter topology diagram

The PCS is a broader concept, which involves the conversion and regulation of electric energy through power electronic devices to achieve power transmission, conversion and control. PCS mainly includes modules such as rectification, inversion, and DC/DC conversion, among which the inverter module is only one of its components.

Energy storage inverter topology diagram

02

Features

From a functional point of view, the photovoltaic inverter mainly focuses on converting the direct current generated by the solar photovoltaic panel into alternating current for use in the power grid or electrical appliances. It optimizes the output power of the solar photovoltaic array through the internal circuit and control module, performs a series of processing on the direct current generated by the photovoltaic panel, and finally outputs alternating current that meets the requirements of the power grid.

The energy storage inverter focuses more on the bidirectional conversion and intelligent management of electric energy. It can not only convert DC to AC, but also convert AC to DC for storage. In addition to realizing the conversion from DC to AC, it also supports BMS/EMS linkage, cluster-level management, and improves the charging and discharging capacity. It can independently manage peak shaving and valley filling locally, and can intelligently dispatch the charging and discharging operations of the energy storage system.

Energy storage inverter

03

Application Scenario

In terms of application scenarios, photovoltaic inverters are mainly used in solar power generation systems, such as household photovoltaic systems, industrial and commercial photovoltaic projects, and large ground power stations. Its main function is to convert the DC power of the solar power generation system into AC power and integrate it into the power grid.

Photovoltaic inverter system diagram

Energy storage inverters, on the other hand, focus more on applications in electrochemical energy storage systems, such as energy storage power stations, centralized or string-type, industrial and commercial, and household applications. In these scenarios, energy storage inverters achieve efficient utilization and storage of renewable energy by intelligently managing the charging and discharging process, providing stable and reliable power support for various application scenarios.

Energy storage inverter system diagram

04

Similarities and differences

In terms of commonalities, both are power electronic devices used for the conversion and regulation of electrical energy to achieve stable operation of the power system. They both need to meet certain electrical safety standards to ensure the safe operation of the equipment.

In addition, since energy storage inverters need to integrate battery management systems, their costs are relatively high. Photovoltaic inverters have relatively simple functions, so their costs are usually lower. At the same time, energy storage inverters also have higher requirements in terms of safety. In addition to meeting basic electrical safety standards, they also need to consider the safety of the battery management system and protection measures in the event of battery failure.

05

Summarize

In summary, there are obvious differences between photovoltaic inverters and energy storage inverters in terms of principles, application scenarios, power output, cost and safety. In practical applications, appropriate equipment should be selected according to specific needs and scenarios.