What is an Inverter

An inverter is one of the key indispensable components of a contemporary electrical system. Its role is to convert direct current (DC) to alternating current (AC) so that the power can be efficiently utilised by various devices and systems. To gain a deeper understanding of the role and importance of inverters, it is first necessary to understand their basic principles and how they work.

In an inverter, the core components usually include electronic components such as transistors, capacitors and inductors, which work in tandem to convert and control electrical energy. By periodically switching the state of these components, the inverter transforms the incoming DC power into AC power with the desired frequency and amplitude. This conversion process not only makes the transmission of power more efficient, but also meets the needs of different devices in terms of the waveform of the power signal and ensures their proper operation.

In addition to converting DC to AC, inverters also perform important functions such as regulating voltage and frequency, protecting electrical equipment, and providing power stability. By accurately controlling the parameters of the output power, inverters can ensure that the power system can operate reliably under a variety of operating conditions and can be adapted to different application requirements.

As a key technology in the field of power conversion and control, inverters provide important support for the stable operation and efficient use of modern electrical systems. An in-depth understanding of the principles and applications of inverters will help us better grasp the direction of the development of electric power technology and promote the process of energy transition and sustainable development.


What is an Inverter


Inverters are analysed by type

Inverters are classified in a variety of ways in different application scenarios, and each type of inverter has its unique characteristics and scope of application. An in-depth understanding of the classification of inverters helps to select the most suitable device for specific needs.

Grid-tie inverters:

Grid-tie inverters are inverters that convert DC power generated by renewable energy generators such as solar photovoltaic panels or wind turbines into AC power and connect it to the utility grid. This type of inverter enables a smooth output of power, allowing renewable energy sources to be interconnected to the utility grid and provide a stable supply of electricity to customers.

Stand-alone off-grid inverter:

Standalone off-grid inverters are typically used in scenarios where access to the utility grid is not possible, such as remote areas, islands, or mobile devices. This type of inverter is capable of converting DC power generated by solar panels or generators into AC power to provide users with an independent power supply to meet their basic power needs.

Hybrid inverters:

Hybrid inverters combine the functionality of both grid-connected and standalone off-grid systems for greater flexibility and reliability. These inverters can deliver power to the utility grid or supply it to standalone loads as needed, and can also be used with battery storage systems for energy storage and management.


Microinverters are small inverters mounted on solar PV panels, with each panel equipped with a microinverter. Compared to traditional centralised inverters, microinverters maximise the efficiency and stability of solar systems as they are able to track the optimal power point of each solar panel independently.

Understanding the features and application scenarios of different types of inverters will help users to choose the most suitable equipment according to their needs and achieve efficient use and reliable supply of electricity.


Inverters are analysed by type


Selection of Inverters

Choosing the right inverter is the key to ensuring that it can effectively drive the equipment and run stably for a long time. Different application scenarios have different requirements for inverters, so several factors need to be considered when selecting an inverter. Below are a few aspects to focus on when selecting an inverter.

Power Requirements

The first thing to consider when choosing an inverter is the power requirement. The power requirement determines how much output capacity the inverter needs to have to drive all connected devices. The steps for determining power demand are as follows:

  1. Determine the total power of the devices: Add up the power of all the devices that need to be connected to the inverter to get a total power value. The power of the equipment is usually indicated on the nameplate in watts (W).
  2. Consider start-up power: Some devices (e.g. electric motors, refrigerators, etc.) have a momentary high power demand at start-up, usually 2-3 times the rated power. Therefore, the starting power of these devices needs to be taken into account when selecting an inverter.
  3. Leaving a margin: In order to ensure that the inverter can work stably for a long time, it is recommended to choose an inverter that is slightly larger than the total power. For example, if the total power is 1000W, you can choose an inverter with 1500W or higher power.

Voltage Requirements

The input voltage of the inverter should match the voltage of the battery or DC power supply. Common input voltages include 12V, 24V and 48V. When selecting, you need to make sure that it is the same as the power supply voltage, in order to avoid that the voltage mismatch will cause the device not to work properly. The specific steps are as follows:

  1. Determine the battery voltage: Check the identification of the battery or DC power supply to determine its output voltage.
  2. Match the inverter voltage: Select an inverter with the same voltage as the battery. For example, if the battery voltage is 12V, you should select an inverter with 12V input.


Selection of Inverters


Equipment Compatibility

Ensure that the AC voltage and frequency output from the inverter matches the equipment to be driven. Generally, household appliances require 220V, 50Hz AC. Pay attention to the following points when selecting:

  1. Check the equipment requirements: check the nameplate of the equipment to be driven to understand its voltage and frequency requirements.
  2. Select an inverter with suitable output: Select an inverter whose output voltage and frequency match the equipment requirements. If driving domestic household appliances, choose an inverter with an output of 220V, 50Hz.

Efficiency of the inverter

The efficiency of the inverter directly affects the battery life and overall energy utilisation. Choosing a high-efficiency inverter will reduce energy waste and increase the range of your equipment. Here are some ways to choose a high-efficiency inverter:

  1. Check the efficiency indicator: Inverters are usually labelled with their efficiency (e.g. 85%, 90%, etc.). The higher the efficiency, the less energy is lost in the conversion process.
  2. Choose brand and model: Choose reputable brands and models, these products are usually guaranteed in terms of efficiency and quality.

Safety features.

Choosing an inverter with a variety of safety features can provide better protection against equipment damage during use. Common safety features include:

  1. Overload protection: prevents damage to the inverter if the total power of the connected devices exceeds the inverter's rated power.
  2. Short-circuit protection: In case of short-circuit at the output, the inverter will automatically cut off power to prevent damage.
  3. Overheat protection: when the inverter temperature is too high, it will automatically shut down to prevent overheating damage.
  4. LOW VOLTAGE PROTECTION: When the battery voltage is too low, the inverter will automatically switch off to prevent damage from over-discharging the battery.

By carefully considering the above aspects, you can choose the inverter that suits your needs and ensure the normal operation and long-lasting use of your equipment.


Equipment Compatibility


Inverter Installation Steps

The installation of an inverter is an important part of ensuring its proper functioning. Correct installation steps will not only ensure the efficient operation of the inverter, but also prolong its service life. Below are the detailed inverter installation steps, including preparation work, mounting the inverter, connecting batteries and equipment, and commissioning and testing.


Before installing the inverter, you first need to make preparations. Here are some key steps:

  1. Selecting an installation location: Choose a location that is well ventilated, dry and away from flammable materials. The inverter generates heat during operation, so it needs a well ventilated environment to dissipate the heat.
  2. Preparing tools and materials: Prepare the required tools, such as screwdrivers, cables, spanners, etc. Also, prepare the necessary materials, such as mounting brackets and cable wires.
  3. Check the inverter and accessories: Before installation, carefully check the inverter and all accessories to make sure there is no damage or missing.

Install the inverter.

The steps to install the inverter are as follows:

  1. Fixing the inverter: Fix the inverter in the selected position. Use screws to securely fasten it to the mounting bracket to ensure that it is stable and does not move.
  2. Connecting the cables: follow the guidelines on the inverter manual to connect the cables at the input and output. Take care to keep the cable connections tight and avoid loosening.
  3. Checking the connections: after completing the cable connections, carefully check all the connections to make sure there is no looseness or poor contact.


Inverter Installation Steps


Connecting Batteries and Equipment.

Connecting batteries and equipment is an important step in the inverter installation as follows:

  1. Connecting Batteries: Connect the input of the inverter to a battery or DC power source. Make sure the positive and negative terminals are connected correctly to avoid damage to the inverter due to wrong polarity.
  2. Connect Device: connect the device to be driven to the output of the inverter. Make sure the voltage and frequency of the device match the output parameters of the inverter.
  3. Check connections: Check all connections again to make sure there are no loose or poor contacts.

Commissioning and Testing

After the installation is completed, debugging and testing is required to ensure that the inverter works properly:

  1. Turn on the inverter: Follow the guidelines in the manual to turn on the power switch of the inverter. Observe the indicator lights and display of the inverter to confirm that it starts up properly.
  2. MEASURING OUTPUT VOLTAGE AND FREQUENCY: Measure the output voltage and frequency of the inverter using a multimeter to ensure that it meets the requirements of the device.
  3. Test equipment operation: Connect the equipment and start it up, observe the operating status of the equipment and confirm that it can work normally.
  4. Detecting abnormal conditions: During the testing process, pay attention to observe whether there are any abnormal conditions, such as noise, overheating or unstable voltage. If problems are found, make adjustments and deal with them in time.

With the above steps, you can ensure the correct installation and normal operation of the inverter. In the process of using, regular checking and maintenance of the inverter can effectively prolong its service life and ensure the safe operation of the equipment.


Commissioning and Testing



Inverters play a vital role in modern electrical systems, converting direct current to alternating current for efficient use of electricity. Understanding the basic principles and working methods of inverters, as well as their types in different scenarios are analysed to help us better select and apply inverters.

23 mayo 2024