Comparative analysis of inverter power supply or inverter

What is an inverter power supply? What does it do? An inverter power supply, also called an inverter, is a DC/AC converter that converts the DC power from the battery pack into AC power with stable output voltage and frequency. Generally refers to a device that converts low-voltage direct current into high-voltage (or low-voltage) alternating current. It can use a battery as a power source to output alternating current. Specifically, for example, a 12V battery cannot power ordinary lights, computers, TVs, etc., but if the battery is converted into ordinary 220V AC power through an inverter and then connected to these electrical appliances, they can work normally.

Generally, the inverter power supply comes with a built-in battery, such as the UPS power supply sold in computer stores. However, the battery itself is small and can only power the computer for a few to ten minutes. It is mainly used to recharge the battery when there is a sudden power outage. Rely on it to continue powering your computer, giving you time to save unsaved files and give you time to shut down gracefully.

use:

It is used in environments without AC power to provide power to AC equipment. Its output power ranges from tens of watts to hundreds of kilowatts; its input DC voltage ranges from a few volts to hundreds of volts.

It is mainly used in the following places:

1. In cars, ships and airplanes, together with the DC power supply on the vehicle, it provides power for AC appliances;

2. In places where there is no power supply, together with other power generation equipment (solar energy, wind energy, hydro energy and various fuel generators), provide AC power to users;

3. As an uninterrupted power supply UPS (Uninterrupted Power Supply) for communication and power systems;

4. As fire emergency power supply EPS (Emergent Power Supply);

5. Use portable power sources to provide temporary AC power, etc.

Inverter is an inverter

An inverter is a DC to AC transformer, which is actually a voltage inversion process like a converter.

principle:

The converter converts the AC voltage of the power grid into a stable 12V DC output, while the inverter converts the 12V DC voltage output by the Adapter into high-frequency, high-voltage AC power; both parts also use the commonly used pulse width. modulation (PWM) technology. Its core part is a PWM integrated controller, the Adapter uses UC3842, and the inverter uses TL5001 chip. The operating voltage range of TL5001 is 3.6~40V. It is equipped with an error amplifier, a regulator, an oscillator, a PWM generator with dead zone control, a low-voltage protection circuit and a short-circuit protection circuit.

Input interface part: The input part has 3 signals, 12V DC input VIN, working enable voltage ENB and Panel current control signal DIM. VIN is provided by the Adapter, and the ENB voltage is provided by the MCU on the motherboard. Its value is 0 or 3V. When ENB=0, the inverter does not work, and when ENB=3V, the inverter is in normal working condition; while the DIM voltage It is provided by the mainboard, and its variation range is between 0 and 5V. Different DIM values ​​are fed back to the feedback terminal of the PWM controller. The current provided by the inverter to the load will also be different. The smaller the DIM value, the current output by the inverter. The bigger.

Voltage starting circuit: When ENB is high level, high voltage is output to light up the Panel's backlight tube.

PWM controller: It has the following functional components: internal reference voltage, error amplifier, oscillator and PWM, overvoltage protection, undervoltage protection, short circuit protection, and output transistor.

DC conversion: A voltage conversion circuit is composed of a MOS switching tube and an energy storage inductor. The input pulse is amplified by a push-pull amplifier and drives the MOS tube to perform switching actions, causing the DC voltage to charge and discharge the inductor, so that the other end of the inductor can receive AC Voltage.

LC oscillation and output circuit: ensure the 1600V voltage required to start the lamp, and reduce the voltage to 800V after the lamp is started.

Output voltage feedback: When the load is working, the sampling voltage is fed back to stabilize the voltage output of the I inverter.

Application areas

1. The 220V electricity obtained by the inverter on the car is 220V 50HZ. The high-end ones are sine wave, and the cheap ones are generally square wave.

The sine wave is the same as the electricity used in the socket, and the square wave can actually be used, but if you use a fan or other equipment with a motor, there will be some noise. The reason why square wave is used is This modulation method is relatively low cost. Generally, the maximum power of the inverter in the car is only 500 watts, and the air conditioner is generally more than 700 watts. Moreover, do you really want to install a home air conditioner on the car??? The air conditioners in the car, including those in buses, are all The engine directly drives the compressor, not electricity. If there is an electrical conversion process in the middle, the loss will be even greater. And it’s not easy to install. It’s better to use a car air conditioner.

2. Connect laptops, TVs, disc players and the like. As long as it is used at its rated power, there will be no problem. However, it should be noted that it is connected to the car battery. Although it usually automatically protects and cuts off power at 11V, To prevent the car from being unable to start due to low voltage, it is still not suitable to be used when the engine is not running, so if the load is relatively large, it is recommended to start the engine. If you are charging your mobile phone, there is no problem.

3. On electric vehicles, there is a module called DC-DC, which is also called a DC converter. This module inputs 48V and outputs 12V. Then you only need to buy a 12V input car inverter to use it. Of course, it would be better if you can buy an inverter with 48V input, but it is probably difficult to buy. Moreover, this module can generally only provide 5A current, no more than 10A, and it is also used for car lights and other things, so it is easy to be overloaded. It is recommended that if you can, buy an extra DC converter. This converter specifically supplies power to your inverter. If the DC converter can only provide 5A, then the inverter input should be less than 5A, otherwise the module may be damaged. Of course, there are some DC converters with very large currents. If your car repair place doesn’t have one, you can go to some electrical stores or ask them to repair it and give you a high-current one, or you can connect multiple DC converters in parallel. In short, Just don't overload him.

4. There is a vvvf traction inverter on urban rail vehicles, which is used for frequency conversion and voltage conversion. During train traction, the high voltage (generally dc750V or DC1500V) is converted into three-phase power with adjustable frequency and voltage for use by the traction motor. During braking, the three-phase electric energy generated by the rotation of the traction motor driven by the train's inertia can be converted into direct current and fed back to the power grid or consumed through the energy consumption module.

The main applications of inverters in the communications field are:

Provides AC auxiliary power to DC power.

Some maintenance tools require AC power. DC power cannot provide AC power, which can be provided with the help of an inverter.

Provide DC-AC conversion function for photovoltaic grid-connected power supply system. Invert the DC power generated by the solar system into AC power and input it into the power grid. There is no better one. I just want to analyze it based on the specific situation in different fields. I hope it will be helpful to netizens. The above is the technical analysis related to inverter power supply, I hope it can help you.