INVERTER GENERATOR VS CONVENTIONAL GENERATOR

 

 

 

Generators only need gasoline as fuel, and they can output electricity for several hours. It can be used to drive household refrigerators, TVs, telephones and mobile phone chargers, and can also illuminate home lights.

 

In addition, Generators can not only guarantee home appliances in the event of a power failure but also provide electricity when camping.

 

For ordinary household use, we recommend a portable generator. But you will find that there are two mainstream products for household generators (with output power between 800W-2500W), conventional generators and inverter generators (digital inverter generators). Under the same output power, the price of a digital inverter generator is expensive than a conventional generator. Inverter generator vs conventional generator, which one should you choose?

 

Conventional Generator

For a conventional generator, its power usually comes from gasoline. (Diesel engines are usually used in industrial production, which is more powerful but noisy). When the conventional generator starts to run, usually the engine starts to work at a speed of more than 3,000 revolutions per minute, generating a voltage of 240 volts and a frequency output of 50 Hz. Of course, the voltage and frequency can be adjusted to meet your application requirements.

 

 

But the conventional generator cannot maintain a very constant output, so the voltage and frequency are changing. This will cause the computer or LED TV to have ripples, crashes, and so on.

In addition, the portable conventional generator has a high speed, consumes more fuel, and generates a loud noise. The weight is about 10-20 kg.

 

 

Inverter Generator

 

The working principle of inverter generators is more complicated, and the original cost is much higher than that of ordinary portable generators. But the power source is still an ordinary engine, and gasoline is also used.

 

The alternating current generated by the engine will first become direct current and then converted into alternating current by the electronic inverter.

At this time, the voltage and frequency of the alternating current can be guaranteed to be stable. Whether you are using a home router, a laptop, or a mobile phone charger, you will not be troubled by the unstable engine speed.

 

In addition, due to the inverter regulation circuit, the response of the engine becomes very fast. Once the output current demand drops, the engine speed will drop immediately; on the contrary, if the demand rises, the engine speed will also rise. Therefore, the inverter generator not only has low noise but also saves about 30% to 40% of fuel. Generally, 2.5 liters of ordinary gasoline can make the inverter generator work smoothly for 3.5-4.5 hours; the same amount is only enough for ordinary generators for 2.5-3 hours.

 

 

Are variable frequency generators better than traditional generators?

 

Working principle of variable frequency generator:

 

A variable frequency generator is a generator that connects and assembles the stator and rotor of the generator through bearings, frame, and end caps to achieve the effect of operation. The variable frequency generator rotates the rotor in the stator through bearings and introduces a certain excitation current through sliding rings. The variable frequency generator turns the stator into a rotating magnetic field, and the stator coil of the variable frequency generator cuts the magnetic field lines to generate induced electromotive force, The variable frequency generator is led out through wiring terminals and then connected to the circuit to generate current.

 

The variable frequency generator generates alternating current in household circuits and other circuits because there is a circuit break at the connection between the brush and the rotor, which causes the rotor to operate in a certain direction and generate alternating current.

 

 

 

There are many differences in design and function between variable frequency generators and traditional generators, among which the design of the flywheel is a significant difference.

 

 

Traditional generator:

 

1. Usually equipped with a flywheel. The main function of the flywheel is to store energy after the generator is started and help the generator maintain a relatively stable speed. Even when the load changes, the inertia of the flywheel helps smooth power output and reduce rpm fluctuations.

2. The presence of the flywheel makes the generator structure relatively large and heavy, which may produce greater noise.

3. Traditional generators directly generate alternating current through mechanical means, and their frequency is directly related to the engine speed. Therefore, when the load changes, the output voltage and frequency may be unstable.

 

Variable frequency generator:

 

1. In some designs, such as digital inverter generators, the traditional flywheel design may be canceled and instead a small motor combined with inverter technology is used. This design makes the generator more compact and lightweight.

2. After canceling the flywheel, variable frequency generators often use advanced electronic control systems and inverters to adjust the output voltage and frequency to ensure the stability of power output and maintain constant voltage and frequency even when the load changes drastically. .

3. Inverter technology allows the generator to operate efficiently in a wider speed range, helping to save fuel, and to work at high speeds, thereby reducing the size and size of the generator while providing the same power output. weight.

4. Inverter generators generally have lower noise levels, in part because they use more efficient engine technology and built-in sound insulation measures, such as sound-deadening foam and optimized cooling systems.

 

 

Frequency converter generators usually do not require a flywheel for the following reasons:

 

1. Different power adjustment methods: Traditional generators rely on the engine speed to maintain a constant AC output frequency. The flywheel here plays the role of energy storage and smooth output, helping to overcome the impact of engine speed fluctuations. The variable frequency generator is equipped with an electronically controlled frequency converter, which can independently adjust the output voltage and frequency and is not directly affected by engine speed fluctuations.

2. Design optimization: The digital inverter generator adopts a more compact and lightweight design, such as using a small high-efficiency motor and directly converting voltage through inverter technology. It no longer relies on the traditional heavy stator and rotor structure, so the flywheel is eliminated. , reduces noise and reduces overall weight.

3. Output characteristics: The goal of the inverter generator is to provide stable and adjustable power output, with its voltage and frequency managed by a built-in electronic control system, rather than purely relying on mechanical structures (such as flywheels) to maintain stability. This allows the generator to operate effectively over a wider range of engine speeds while maintaining the quality of the output electrical energy.

4. Application scenarios: Variable frequency generators are often used in situations that require high power supply quality, such as precision electronic equipment, medical equipment power supply, etc. These applications require highly stable voltage and frequency. Electronically controlled frequency conversion technology can meet this requirement better than mechanical flywheels. One need.

To sum up, the inverter generator achieves better performance by canceling or replacing the traditional flywheel design and integrating inverter technology, including smaller size, lighter weight, lower noise, and higher efficiency. and more stable power output.

 

 

Inverter generators save more materials than traditional generators, mainly due to the following aspects:

 

1. Efficient energy conversion: Variable frequency generators use advanced electronic control technology and high-performance magnetic materials to convert energy more efficiently under different load conditions. This means they produce the same power output at lower fuel consumption, reducing the need for larger engine and generator components.

 

2. High-speed operation: The engine of the inverter generator can operate in a wide speed range and usually operates at a higher efficiency point. This allows the use of smaller, lighter engines to achieve the same power output, significantly reducing the amount of metal and other materials used compared to traditional generators that require larger, heavier engines to ensure stable output.

 

3. Reduction in volume and weight: Due to the use of high-frequency AC technology and compact design, the alternator part of the variable frequency generator can be designed smaller and lighter. This not only reduces material requirements for the generator itself, but also eases requirements for support structures and packaging materials.

4. Optimized design: The design of variable frequency generators is often more integrated. Through the inverter and intelligent control system, the output can be accurately adjusted, avoiding the redundant components and components that have to be added in traditional generators to adapt to various load conditions. Material.

5. Pure power output: The variable frequency generator can produce higher quality alternating current, that is, pure sine wave output with small harmonic content, which reduces the dependence on external filters and other power conditioning equipment, and indirectly saves materials.

 

 

There are some differences in heat dissipation design between inverter generators and traditional generators. These differences mainly stem from their working principles and application requirements.

 

Cooling system design:

 

Variable frequency generators are usually equipped with an independent cooling system, and their cooling fans may be powered by an independent power supply. The purpose of this is to ensure that even when the frequency converter adjusts the motor speed to a low speed, the cooling system can continue to work effectively and avoid damage to the motor due to overheating. Because the natural cooling capacity of the motor will decrease during variable frequency operation, especially low-frequency operation, an independent heat dissipation system is a necessary design.

 

Temperature rise and heat dissipation requirements:

 

Inverter generators are designed to withstand a wider range of frequency changes, so their insulation levels and heat dissipation designs tend to be more stringent. Frequency conversion operation may cause the internal temperature rise of the motor to increase, especially when running at high frequencies, so enhanced heat dissipation measures are crucial to maintaining long-term stable operation of the motor.

Ordinary generators operate more at a fixed frequency, and their cooling systems (such as fans) are usually directly connected to the output shaft of the generator and change as the generator speed changes. This means that under rated working conditions, ordinary generators can rely on their own operation to provide sufficient heat dissipation, but under non-rated conditions, such as overloading or low-speed operation, the heat dissipation effect may be compromised.

 

Efficiency vs. Heat Generation:

 

Inverter generators may be more efficient than traditional generators under part-load conditions because they can adjust rotational speed to optimize operation and reduce unnecessary energy consumption and heat generation. However, the efficiency of traditional generators may decrease under non-full load conditions and produce relatively large amounts of waste heat.

 

 

To sum up, the heat dissipation design of variable frequency generators is more inclined to provide stable heat dissipation performance, especially under a wide range of operating conditions of variable frequency operation, to ensure the reliability and life of the motor. The heat dissipation design of traditional generators is more based on its fixed operating conditions and may not be as flexible and adaptable as inverter generators.

 

 

 

 

 

Advantages of variable frequency generators compared to traditional generators:

 

1. The working speed of a variable frequency generator can vary over a large range, making it a good match for the generator and achieving fuel savings;

 

2. Variable frequency generators can operate in high speed areas, thus outputting the same power. Variable frequency generators have much smaller weight and volume. In terms of frequency conversion generators, it means increasing power and having a higher specific power;

 

3. The AC generator operates at a high speed, and the variable frequency generator also reduces weight and volume;

 

4. Based on the above 2 and 3 points, the editor has concluded that it has also saved a lot of metal materials;

 

5. The output power of the AC generator is of high quality – pure sine wave output with very low harmonic content.