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The Functionality of an Inverter

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Inverter refrigerators and air conditioners are commonplace in offices and homes. Inverter appliances can be found in many shops and online. They are energy efficient and customers buy them. However, sales reps and commercials don’t explain how inverters work.
What does an inverter do?

Also known as AC Drives or VFDs (variable frequency drives), inverters can also be called AC Drives. These electronic devices can convert DC (Direct Current), to AC (Alternating current). It also controls the speed and torque of electric motors.

Most devices that we use for work, such as small electronics, transportation and office appliances, have electric motors. These motors require electricity to operate. To avoid energy waste, it is important to match the motor’s speed with the process. A 24v 5000w inverter can be used to control electric motors in factories to increase productivity and save energy.
Technology behind Motor Control and Power Conversion

An AC drive is a combination of an electric motor and a power supply. The AC drive regulates the power and draws it in. The motor then receives the regulated power.

An AC drive is composed of a rectifier unit and a DC intermediatecircuit. The inverse conversion circuit is also included. An AC drive’s rectifier unit can be either unidirectional or bidirectional. The first can run and accelerate the motor using energy from the electric network. Bidirectional rectifiers can be used to take the mechanical rotation energy of the motor and return it to the electrical network. The electrical power will be stored in a DC circuit for the inverse converter unit’s use.
The AC drive undergoes an internal process before the motor receives the regulated power. The AC voltage is converted from AC voltage to the input power by a rectifier unit. The DC intermediate circuit smoothens out the DC voltage. The DC intermediate circuit then converts the DC voltage into AC voltage.
This allows the AC drive’s to adjust the voltage and frequency supplied to the motor according to the process. When the output voltage is higher, the motor’s speed increases. The operator interface allows you to control the speed of your motor.
1. Energy-saving

AC drives are a great option for pump and fan applications. AC drives are superior to on/off controls and dampers. They can control motor rotation, which can lower energy consumption by up to 20 to 50%. This is similar to decreasing the car’s speed. You don’t need to use breaks; you can reduce the speed by pressing lightly on the accelerator.
2. Soft Starters

AC Drives start the motor by providing power at a low frequency. The frequency and speed of the motor are gradually increased until they reach the desired speed. Operators can adjust the acceleration and deceleration at will. This is ideal for conveyor belts and escalators to prevent load dropouts.
3. Controlled Start Current

To start an AC motor, it takes 7 to 8 times the full-load current. AC drives reduce the starting current which results in less motor rewinds and extends motor life.
4. Reduction in power line disturbances

An AC motor running across the line can cause a huge voltage drop and drain the power distribution system. When a large motor starts, sensitive equipment like computers and sensors can trip. AC drives eliminate this voltage sag because they remove the motor’s power and not trip it.
5. You can easily change the direction of rotation

AC drives are capable of handling frequent start-stop operations. After changing the rotation command, it only requires a small amount of current to alter the direction of rotation. An inverter drive can control the number of revolutions and can adjust the output of stand mixers to produce the correct direction of rotation.
6. Simple Installation

AC drives come pre-programmed. The factory has already wired the auxiliaries, communication lines and motor leads to control power. Only the contractor will need to connect the line to power source to supply AC drive.
7. Adjustable Torque Limit

AC Drives can prevent motor damage by controlling torque accurately. In case of a jammed motor, it will continue rotating until the overload device is opened. To limit torque, an AC drive can be used to limit torque to the motor.
8. Elimination of mechanical drive components

AC drives can provide the required load speed without any gearboxes or speed-increasing devices. This reduces maintenance costs and increases floor space.

Low and medium voltages

AC drives can be classified as either Low Voltage (LV), or Medium Voltage(MV). There are many factors that you should consider when purchasing AC drives.

An LV drive can produce alternating current of between 240 and 600 volts (VAC). These drives are used in compressors, pumps, conveyor belts, and compressors. Because LV drives are less stressful on the motors, they require minimal maintenance. It also uses less energy. An LV drive is capable of producing high frequency and superior motor performance at low voltages, which reduces production costs.

Low voltage can create more current. When LV drives are connected to high-powered (HP) machines, they generate more heat and increase the room temperature. Higher current equals more heat generated. Additional air-conditioning and venting are required.

MV drives are used in large, multi-megawatt electric motors that power metal processing plants and power stations. They can produce up to 4160 VAC, but they can also reach as high as 69,000 VAC. To achieve high output voltages, they require high input voltage. MV drives are more expensive than LV drives in terms of cost. They require higher-quality transformers and breakers. They are more physically large than LV drives. Unlike LV drives, which can be maintained in-house by an electrical maintenance team, MV Drives require regular maintenance.

Both companies and consumers want to save energy. Inverters have been developed for machineries and other regular appliances. Inverters can be hidden in places with sufficient ventilation. They play an important role in energy savings. It is possible to control office devices according to demand and reduce energy consumption.