Solar Inverters: The Core Driver of Green Energy Conversion
In the wave of renewable energy, solar energy, with its clean, unlimited and widely distributed
characteristics, has become an important force driving the global energy transition.
Solar power systems not only reduce dependence on fossil fuels, but also promote sustainable economic
development. And in this green revolution, solar inverters play a crucial role as the key device
connecting solar panels to the grid or load.
In this paper, we will delve into the working principle, types, functions of solar inverters and their impact on the efficiency of solar energy utilisation, revealing their key role in promoting the popularity and efficient use of solar power.
What is a Solar Inverter
A solar inverter is a device that converts the direct current (DC) generated by solar panels into
alternating current (AC). AC is the type of current we use in our daily lives, so an inverter is the
bridge that converts solar energy into a form we can use to power appliances, lighting, and other
devices.
How solar inverters work
The core working principle of a solar inverter involves several key steps. Firstly, solar panels
convert sunlight into DC electricity through the photovoltaic effect. Subsequently, the inverter
receives this DC power and converts it to AC power through its internal circuitry, a process that
typically involves pulse width modulation (PWM) and inverting operations. Ultimately, the
converted electricity can be supplied directly to the home or sent back to the grid.
Types of Solar Inverters
Solar inverters can be classified into various types according to power and function.
Classified according to power supply method
Grid-connected inverter:
It is suitable for systems that feed the generated power directly into
the grid. It synchronises with the grid and ensures that excess power is fed back to the grid under
normal grid conditions.
Off-grid inverter:
Suitable for areas where there is no grid connection and is usually used in
conjunction with a battery system. Can provide power independently and supports battery
charge/discharge management.
Hybrid inverters:
Switch between grid-connected and off-grid modes, usually with an in-built battery management system, for users who are both grid-connected and wish to store energy.
Categorised by function
Pure Sine Wave Inverter:
The output voltage waveform is smooth and continuous, highly consistent with the grid current waveform, and capable of providing high-quality power. It is suitable for equipment that requires high power quality, such as precision electronic equipment, medical equipment and communication equipment, to ensure stable operation.
Modified Sine Wave Inverter:
The output waveform is close to sine wave but with some distortion, and the cost is relatively low. It is suitable for household appliances with low current requirements, such as TV sets, washing machines, etc. It can meet the basic power needs of these devices and reduce system costs.
Multi-functional smart inverter:
It not only has the function of power conversion, but also integrates intelligent functions such as load management and energy monitoring.
It can monitor the status of the power system in real time and make automatic adjustments according to the actual demand, improving the efficiency of energy utilisation.
In addition, the multifunctional smart inverter also supports remote monitoring and management, making it convenient for users to grasp the status of the power system and make adjustments at any time.
The Important Role of Solar Inverters
Solar inverters have multiple important roles in the overall solar power system:
Electrical energy conversion:
directly responsible for the conversion of DC to AC power,
making solar energy easier to use and store.
Monitoring function:
Most inverters are equipped with an intelligent monitoring system
that tracks system performance in real time to ensure efficient operation.
Grid Connection:
Inverters can regulate output and connect to the grid to ensure stable
output and prevent overloading.
Safety:
Multiple protection mechanisms such as overload, overvoltage and short circuit are
provided to ensure safe use.
Key Factors in Buying Solar Inverters
There are several key factors involved in the purchase of a solar inverter, which are analysed in
detail below:
Power Matching and Capacity Expansion
Rated output power
It indicates the inverter’s ability to supply power to the load, which should
be selected according to the total power of the power-using equipment and the demand for
system capacity expansion. Generally speaking, the rated output power of the inverter should be
selected to be 10%~15% larger than the total power of the power-using equipment, in order to
cope with the maximum load and the possible future expansion demand.
System expansion
Consider the possible increase in the number of PV modules in the future,
and select an inverter model that is easy to upgrade the power.
Adaptability to environmental conditions
Temperature and humidity
The inverter needs to adapt to different operating temperatures
and humidity to ensure stable operation under the specified conditions.
Altitude
The inverter should be able to work normally within the specified altitude to avoid
performance degradation caused by high altitude.
Grid access and communication function
Grid Access Requirements
The inverter needs to comply with the access standards of the local
power grid to ensure safe and stable connection with the grid.
Communication function
Inverters with remote communication function allow users to
remotely check the machine’s operation status and stored data, improving operation and
maintenance efficiency.
Off-grid solar system
In case of off-grid solar system, there is no need to consider grid access,
and the off-grid solar inverter can be configured with backup power supply or energy storage
equipment (e.g. battery). In case of insufficient or no solar power generation (e.g. at night or on
cloudy or rainy days), the backup power supply or energy storage device can supply power to the
load to ensure the continuous supply of electricity.
Efficiency and Reliability
Overall efficiency
It indicates the size of the inverter’s own power loss. A high-efficiency inverter
can reduce energy loss and improve the system’s power generation efficiency. When selecting,
attention should be paid to the efficiency value of the inverter under full load and low load
operation.
Reliability
The inverter should have reasonable circuit structure, strict component selection and
perfect protection functions (such as input DC polarity reversal protection, AC output short
circuit protection, overheat and overload protection, etc.) to ensure stable operation under
adverse conditions.
Waveform Quality
Output waveform
For large-scale solar projects, the output of the inverter should be sinusoidal
waveform with less distortion to reduce harmonic pollution to the power grid and improve
power quality.
Solar Inverter Brand Recommendation
In the field of solar inverters, there are several brands that have won wide recognition in the
market by virtue of their excellent product performance, wide range of application scenarios and
perfect after-sales service system. Here are some of the best solar inverter recommended
brands:
HUAWEI
Brand Background:
As a leading global information and communications technology solutions
provider, Huawei has also demonstrated strong technical strength and innovation in the field of
photovoltaics.
Product features:
Huawei’s smart PV solutions integrate digital information technology with PV
technology in depth, and have launched a variety of high-efficiency, intelligent inverter products.
Its string inverters have won the praise of a large number of users around the world thanks to
their excellent power range and stable performance.
SUNGROW
Brand Background:
Since its establishment in 1997, Sungrow has been committed to the research
and development, production and sales of new energy power supply equipment, and is a global
leader in the field of new energy.
Product features:
Sunpower’s PV inverter products are known for their wide power range (from
3KW to 3MW) and excellent performance. Whether it is a home PV system or a large ground
power station, they can provide perfect solutions. Its inverters have been certified and tested by
a number of international certification bodies, and its products are exported to many countries
and regions around the world.
Growatt
Brand Background:
Founded in 2010, Growatt is a new energy enterprise focusing on the research, development and manufacturing of solar grid-connected, off-grid and energy storage
inverters as well as user-side smart energy management solutions.
Product features:
Guruwate’s solar grid-connected inverters cover a wide range of power levels,
and we also provide off-grid and energy storage inverters. The products are widely used in
household, commercial, PV poverty alleviation, large-scale ground power stations and various
types of energy storage power station scenarios. With its excellent product performance and
perfect after-sales service system, it has established a good brand image worldwide.
GOODWE
Brand Background:
Founded in 2010, Goodway focuses on the R&D, production and sales of solar
PV inverters and their monitoring products.
Product features:
GOODWE has developed more than 20 series of grid-connected and energy
storage PV inverter products with a wide range of power coverage to fully meet the needs of
household, poverty alleviation, industrial and commercial, and large-scale power plants. Its
products are characterised by high efficiency, stability and ease of operation, and have won the
favour of many users around the world.
TOPBULL
Brand Background:
TOPBULL is a new energy high-tech enterprise specialising in the research,
development and manufacturing of solar panels, off-grid inverters, energy storage batteries and
other products.
Product features:
TOPBULL off-grid inverter products are known for their high efficiency, stable
and reliable performance, very affordable and cost-effective, and its pure sine wave inverter
series products have won the recognition of a large number of users around the world.
SINENG
Brand Background: Founded in 2012, SINENG is a high-tech enterprise focusing on the R&D,
manufacturing and sales of power electronic products.
Product features: SINENG is deeply engaged in the field of power electronics power conversion
and control, providing users with solutions and system integration for PV grid-connected
inverter, energy storage bi-directional converter, power quality management, etc.
SINENG’s inverter products have a wide range of power ranges. Its inverter products have a wide range of
power, stable and reliable performance, and are the preferred supplier for many photovoltaic
projects.
When choosing a solar inverter brand, it is recommended that comprehensive consideration be
given to factors such as specific application scenarios, load demand, budget and after-sales
service.
The above recommended brands are for reference only, and the specific choice needs to
be judged according to the actual situation.
Development Trends and Challenges of Solar Inverters
With the continuous progress of solar technology and the acceleration of global energy
transition, the solar inverter industry is ushering in unprecedented development opportunities.
In terms of technological innovation, the design of high-efficiency inverters, the application of
intelligent and IoT technologies, and modular design will become an important direction for the
development of inverters in the future.
In terms of market trends, the global solar inverter market will continue to grow, especially in China, the United States, Europe, Pakistan and other countries and regions, with strong market demand and strong policy support.
However, the solar inverter industry is also facing many challenges. Cost reduction, material
supply issues, and environmental adaptability and durability challenges are key constraints to
inverter performance improvement and widespread application.
In addition, inverter troubleshooting and after-sales service are also the focus of users’ attention. Therefore, inverter manufacturers need to continue to innovate and improve product quality and service levels to meet market demand and user expectations.
Summary
As a key component in a solar power system, the performance and quality of solar inverters
directly affect the overall efficiency and stability of the system. Through in-depth understanding
of the working principle, types, functions, and selection and maintenance points of inverters, we
can make better use of solar energy resources and promote the development of green energy. In
the future, with the continuous progress of technology and market development, solar inverters
will play an even more important role in promoting the global energy transition and achieving
sustainable development goals.