Inverter Drives

Inverter drives, also known as adjustable speed drives, variable frequency drives (VFD), or AC drives, are devices that convert AC power to DC power, allowing precise control of motor speed and output. These versatile devices enable users to adjust motor operations to match specific needs, significantly enhancing efficiency and reducing electrical energy waste across various applications. Inverter drives are critical in applications ranging from small electronics to large industrial machinery, facilitating optimal performance with reduced energy consumption.

Inverter drives are available in single-phase or three-phase models, catering to different power requirements. They also come with different IP ratings, which indicate their degree of protection against environmental factors (see our guide for more details on IP ratings).

How Do Inverter Drives Work?

Inverter drives are controlled by inputting specific frequencies or parameters into the device. This allows for greater control over your machinery and operations with more precision. Inverter drives are situated between an electrical supply and a motor, with the inverter allowing the power to be regulated to suit the application.

The working principle of an inverter drive involves several key components: a rectifier unit, a DC intermediate circuit, and an inverse conversion circuit. Initially, power enters the AC drive and reaches the rectifier unit where AC voltage is converted to DC voltage. This can be a unidirectional rectifier, which only draws energy from the electrical network to run the motor, or a bidirectional rectifier, capable of also converting mechanical energy from the motor back into the electrical system.

After conversion to DC, the voltage passes through the DC intermediate circuit, which stabilises and smoothens it before it reaches the inverse conversion circuit. Here, the DC voltage is converted back to AC, but with the ability to adjust the frequency and voltage according to the operational demands. By controlling the output voltage frequency, the speed of the motor can be precisely managed, allowing for variable speed control based on the requirements of the task at hand. This adjustment process is typically managed via an operator interface, providing seamless control over motor speed and enhancing the efficiency and effectiveness of motor-driven applications.

Benefits of Inverter Drives

• Control small appliances such as desk portable fans or pump loads
• Larger appliances such as high torque machine control
• Digital operation LED input screens (for easy parameter setting, input and monitoring)
• Compact and sleek design
• Easy installation
• Emergency stops
• Energy-saving

Applications of Inverter Drives

Inverter drives are integral in a multitude of industrial applications, particularly where precise control of motor speed and torque is crucial. Their versatility allows them to be employed effectively in both simple and complex machinery:

• Small Appliances: In settings like home and office environments, inverter drives manage the operational speeds of devices such as fans, ensuring optimal airflow with efficient energy use.
• Pump Systems: They adjust the flow and pressure in pumps, commonly used in sectors such as water management, HVAC systems, and chemical processing, enhancing system responsiveness and energy efficiency.
• High Torque Applications: Inverter drives are crucial in heavy industrial environments where they control high torque machines, such as mixers and extruders in manufacturing plants, allowing for precise performance adjustments based on real-time production requirements.

How to Order Inverter Drives From RS

RS is a renowned supplier and distributor of inverter drives, tailored to meet the needs of any industrial, commercial, or project-specific application. We offer a wide selection of inverter drives from top brands including RS PRO, Danfoss, Eaton, Omron, Schneider Electric, and Siemens. This diverse range ensures that you can find the ideal solution for precise control of motor speed and torque across various applications.

Delivery Information for Australia

To ensure timely delivery of your inverter drives, please place your orders by 5 pm AEST from Monday to Friday. We offer next working day delivery for items that are stocked locally, although delivery times may be extended in some regional areas. For a comprehensive overview of all our delivery services, including special options like same-day delivery and consolidated shipments, please visit our delivery information page.