With the advancement of modern technology, inverters have greatly improved the convenience of our lives. In foreign countries, inverters are commonly used to power appliances and tools by connecting them to batteries, especially in cars during work or travel.

In this blog, we will explore the function, features, working principles, classification, usage considerations, installation methods, common problems, and troubleshooting techniques related to inverters.

The Functions of Inverters:

1. Inverters convert DC energy (from batteries or storage batteries) into AC power (usually 220V and 50Hz sinusoidal or square wave). In simple terms, an inverter is a device that converts DC power into AC power. It consists of an inverter bridge, control logic, and filtering circuit.

2. Inverters fulfill the need for AC power while on the move. In particular, they provide 220V AC power from batteries for various appliances and tools, which is essential in today's mobile lifestyle.

Inverters are widely used in applications such as air conditioners, home theaters, power tools, sewing machines, DVD players, computers, televisions, washing machines, range hoods, refrigerators, video recorders, massagers, fans, lighting, and more.

Features of Inverters:

1. High conversion efficiency and quick startup.

2. Good safety performance: Inverters have five types of protection functions: short circuit protection, overload protection, over/under voltage protection, and over-temperature protection.

3. Excellent physical performance: Inverters are housed in all-aluminum casings, which provide good heat dissipation and resistance to friction and external impacts.

4. Strong adaptability and stability under various loads.

Working Principle of Inverters:

1. An inverter is a DC-to-AC transformer and a voltage inversion process. The converter transforms the AC voltage from the grid into stable 12V DC output, while the inverter converts the 12V DC voltage from the adapter into high-frequency high-voltage AC power. Both components employ pulse width modulation (PWM) technology, with a PWM-integrated controller at their core.

2. Input interface: The input section consists of three signals: 12V DC input (VIN), working enable voltage (ENB), and panel current control signal (DIM).

VIN is provided by the adapter, ENB voltage is supplied by the MCU on the mainboard (either 0V or 3V, where 0V indicates the inverter is not working and 3V represents normal operation), and DIM voltage is provided by the mainboard (ranging from 0V to 5V). The DIM value feedback to the PWM controller determines the current supplied by the inverter to the load.

Classification of Inverters:

1. Based on the frequency of the AC power output, inverters can be classified as line-frequency inverters, medium-frequency inverters, and high-frequency inverters. Line frequency inverters have a frequency of 50-60Hz, while medium-frequency inverters range from several hundred Hz to a few kHz, and high-frequency inverters have frequencies ranging from several kHz to MHz.

2. Based on the number of phases of the AC power output, inverters can be single-phase, three-phase, or multi-phase inverters.

3. Based on the direction of the inverted power, inverters can be classified as active inverters (supplying power to the industrial grid) or passive inverters (supplying power to specific loads).

4. Based on the main circuit configuration, inverters can be classified as single-ended inverters, push-pull inverters, half-bridge inverters, and full-bridge inverters.

5. Based on the type of main switch devices, inverters can be categorized as thyristor inverters, transistor inverters, field-effect transistor (FET) inverters, and insulated gate bipolar transistor (IGBT) inverters.

They can also be classified as "semi-controlled" and "fully-controlled" inverters. The former lacks self-turn-off capability and relies on current interruption, while the latter has self-turn-off capability and control over both on and off states.