Definition of 3 Phase Solar Inverter

June 6, 2024

Definition of 3 Phase Solar Inverter

3 Phase Solar Inverter is a device that converts direct current (DC) generated by a solar photovoltaic system into alternating current (AC) and is suitable for three-phase power systems. Unlike single-phase inverters, three-phase inverters can output three-phase AC power, which is suitable for supplying power to industrial and commercial equipment that requires three-phase power. It is one of the core components of a solar power generation system, which can effectively convert solar energy into electricity and power various loads by connecting to the grid or operating independently. Three-phase inverters not only improve the stability and efficiency of power output, but also better balance the grid load and reduce the impact of single-phase voltage fluctuations.

Features and working principle

Features

High-efficiency conversion: Three-phase solar inverters have efficient energy conversion capabilities, can effectively convert DC to AC, and maximize the use of solar resources.
Three-phase balanced output: Output stable three-phase AC, suitable for equipment that requires three-phase power, reducing losses and voltage fluctuations in power transmission.
Intelligent control system: Equipped with advanced MPPT (maximum power point tracking) technology, it can optimize the output of solar panels in real time and improve the overall efficiency of the system.
High reliability: The design is sturdy, with characteristics such as waterproof, dustproof, and high temperature resistance, and can operate stably in various harsh environments.
Grid-connected and off-grid functions: Support grid-connected operation, transmit excess power back to the grid, and can also supply power independently in off-grid mode to ensure the continuity of power consumption.
Remote monitoring and management: Most three-phase inverters support remote monitoring, and can view the system operation status in real time through smartphones or computers, and perform fault diagnosis and maintenance.

Working principle

The working principle of the three-phase solar inverter mainly includes the following steps:

DC input: The solar panel converts light energy into DC power and inputs it into the inverter through the connecting line.
Maximum Power Point Tracking (MPPT): The MPPT controller inside the inverter monitors the output voltage and current of the solar panel in real time and adjusts the operating point to ensure maximum power output.
DC to AC conversion: The MPPT-optimized DC power is converted into AC power through the power conversion unit inside the inverter. This process involves high-frequency switches and filtering circuits to ensure that the output AC power has a stable frequency and voltage.
Three-phase output: The converted AC power is distributed to the three-phase output terminals to form a three-phase balanced AC output to supply loads that require three-phase power.
Grid-connected or off-grid mode: In grid-connected mode, the inverter transmits the generated AC power to the grid, and the excess power can be sold to the power company. In off-grid mode, the inverter ensures the continuity of power consumption through a battery energy storage system.

Types of 3 Phase Solar Inverter

1. Grid-connected three-phase solar inverter

Features:

Directly connected to the grid: This type of inverter directly connects the electricity converted from solar energy to the grid, suitable for large-scale commercial and industrial applications.
Efficient MPPT technology: Equipped with multi-channel MPPT tracking technology to improve the utilization efficiency of solar panels.
No battery storage: No battery is required, the system cost is low, but it cannot provide electricity when there is no sunlight.

Application scenarios: large factories, commercial buildings, photovoltaic power stations.

2. Off-grid three-phase solar inverter

Features:

Independent operation: does not rely on the grid, suitable for areas where the grid cannot cover.
Battery energy storage: equipped with a battery energy storage system, it can also provide electricity at night or on cloudy days.
High stability: can work stably in harsh environments to ensure the continuity of power supply.

Application scenarios: remote areas, rural electrification, emergency backup power supply.

3. Hybrid three-phase solar inverter

Features:

Combination of grid-connected and off-grid: It can be connected to the grid and automatically switch to off-grid mode when the grid fails.
Smart management: Intelligent scheduling of battery energy storage and solar power generation to maximize energy efficiency.
High flexibility: Adapt to a variety of application needs and provide stable and reliable power supply.

Application scenarios: smart microgrids, commercial complexes, residential and office complexes.

4. Micro inverter

Features:

Modular design: Each solar panel is equipped with a small inverter, and the system is highly scalable.
Independent MPPT: Each panel has independent maximum power point tracking to improve overall system efficiency.
Easy maintenance: Easy troubleshooting and low maintenance costs.

Application scenarios: Home photovoltaic systems, small commercial projects, distributed photovoltaic power generation systems.

Different types of three-phase solar inverters are suitable for different application scenarios. Choosing the right type according to the needs can maximize the advantages of the solar system.

Application scenarios

1. Industrial Applications

In the industrial field, three-phase power is the mainstream demand. Three-phase solar inverters can provide stable three-phase power to factories, manufacturing workshops and other industrial facilities to ensure efficient operation of production equipment. By using solar power generation, industrial users can significantly reduce electricity costs, reduce dependence on traditional fossil fuels, and promote green production.
Typical applications: large manufacturing plants, mechanical processing workshops, food processing plants.

2. Commercial buildings

Commercial buildings such as shopping malls, office buildings, hotels, etc. usually have large power demands and are mostly three-phase power systems. Installing three-phase solar inverters can provide part or all of the power needs of these buildings and reduce operating costs. In addition, the installation of solar energy systems can also improve the green certification of buildings and enhance their market competitiveness.
Typical applications: office buildings, shopping malls, hotels.

3. Agriculture and rural areas

In agriculture and rural areas, power supply may be unstable or insufficiently covered. Three-phase solar inverters provide a reliable source of power for farmland irrigation, agricultural product processing equipment, and rural residents, improving living and production conditions. Using solar power generation can also reduce dependence on diesel generators and reduce environmental pollution.
Typical applications: farm irrigation systems, agricultural product processing equipment, rural residences.

4. Public infrastructure

Public infrastructure such as schools, hospitals, government office buildings, etc. usually have peak electricity demand. Three-phase solar inverters can provide stable power supply for these facilities to ensure their normal operation, especially in remote areas or areas with unstable power grids, and can play an important role.
Typical applications: schools, hospitals, government office buildings.

5. Transportation and communications

Traffic signal systems, communication base stations, etc. also require stable and reliable three-phase power supply. Three-phase solar inverters can provide continuous power support in these areas to ensure the normal operation of transportation and communication systems, especially in remote areas or when disasters occur, the independent power supply capacity of solar systems is particularly important.
Typical applications: traffic signal systems, communication base stations, transportation hubs.

How to choose a suitable 3 Phase Solar Inverter

1. Determine power requirements
When choosing a three-phase solar inverter, you first need to determine the actual power requirements. This includes the total power of the load, daily power consumption, and peak load conditions. Based on this data, select an inverter with the right power range to ensure that it can meet the power demand without overloading.

2. Consider the efficiency of the inverter
The efficiency of the inverter directly affects the performance of the entire solar system. Choosing an inverter with higher efficiency can maximize the use of solar resources and reduce power conversion losses. Generally, the efficiency of high-efficiency inverters is above 95%, and it is recommended to choose products that meet or exceed this efficiency standard.

3. Evaluate the MPPT function of the inverter
Maximum power point tracking (MPPT) is one of the important functions of the inverter. A high-quality MPPT controller can optimize the output of the solar panel in real time and improve the overall efficiency of the system. Checking whether the inverter is equipped with advanced MPPT technology and the input voltage range it supports is an important step in choosing the right inverter.

4. Durability and reliability of the inverter
Inverters usually need to operate for a long time under various environmental conditions, so their durability and reliability are very important. Choosing an inverter with waterproof, dustproof, and high temperature resistance can ensure stable operation in harsh environments. In addition, understanding the warranty period and after-sales service of the inverter can also provide guarantees for subsequent maintenance.

5. Investigate the grid-connected and off-grid functions
Choose the appropriate inverter type according to the specific application requirements. If the power needs to be connected to the grid, choose a grid-connected inverter; if it is used in an area without grid coverage, choose an off-grid inverter. For application scenarios with both grid-connected and off-grid requirements, hybrid inverters are a more ideal choice.

6. Understand remote monitoring and management functions
Modern inverters are usually equipped with remote monitoring and management functions, which allows users to view the system operation status in real time through smartphones or computers, perform fault diagnosis and maintenance. Choosing an inverter that supports remote monitoring can greatly improve management efficiency and promptly discover and solve potential problems.

7. Refer to user reviews and brand reputation
Finally, referring to other users’ reviews and feedback will help you understand the actual use effect and reliability of the inverter. Choosing well-known brands and reputable products usually provides higher quality assurance and perfect after-sales service.

How to install and maintain

1. Installation preparation

Site selection: Choose an installation location that is well ventilated, dry and not exposed to direct sunlight to ensure that the inverter can dissipate heat normally and avoid overheating.
Tool preparation: Prepare the tools and equipment required for installation, including screwdrivers, electric drills, wires, sockets, fuses, etc.
Inspect equipment: Before installation, carefully check the integrity of the inverter and other related equipment to ensure that there is no damage or defects.

2. Installation steps

Install the bracket: First, according to the installation manual of the inverter, install the fixing bracket of the inverter on the wall or bracket to ensure that it is stable and secure.
Fix the inverter: Install the inverter firmly on the bracket and fix it with screws to ensure that it does not loosen.
Connect cables: According to the electrical wiring diagram, correctly connect the cables of the solar panel, inverter and grid. Make sure all connections are firm and meet safety regulations.
Ground wire connection: In order to prevent electric shock and equipment damage, the ground wire must be properly connected to ensure the safe operation of the inverter.
Debugging and testing: After the installation is completed, perform preliminary debugging and testing to ensure that the inverter and the entire system can operate normally. Check whether the parameters are set correctly and make sure there is no poor cable contact or short circuit.

3. Daily maintenance

Regular inspection: Regularly check the appearance and wiring of the inverter to ensure that there are no loose or damaged parts. In particular, check the firmness of the grounding wire and cable connection points.
Cleaning and maintenance: Keep the environment around the inverter clean to avoid dust and debris accumulation that affects heat dissipation. If necessary, clean the surface of the inverter with a dry cloth or professional tools, but avoid water and liquid from entering the inside of the device.
Monitoring system operation: Through the remote monitoring system, the operating status and performance parameters of the inverter are monitored in real time. Discover and handle abnormal situations in a timely manner to ensure efficient operation of the system.
Software update: Pay attention to the firmware update information of the inverter manufacturer, upgrade the software in a timely manner, and optimize system performance and safety.
Professional maintenance: Regularly ask professional technicians to perform comprehensive system inspections and maintenance to ensure the long-term and stable operation of the inverter and the entire solar system.

4. Common fault handling

Overheat protection: If the inverter has overheat protection, check whether the cooling fan is working properly and ensure that the installation location is well ventilated and avoid direct sunlight.
Abnormal output: If the inverter output is abnormal, check whether the cable connection is firm and ensure that the input and output voltages of the solar panel and inverter are normal.
Alarm prompt: If the inverter issues an alarm prompt, refer to the equipment manual to find the cause of the fault and take corresponding measures. If it cannot be solved, contact professional technicians in time.
Through correct installation and regular maintenance, the efficient and safe operation of the three-phase solar inverter can be ensured, providing reliable power support for the system.

Definition of 3 Phase Solar Inverter