Home / Design / Smooth and reliable speed control for DC motors

Smooth and reliable speed control for DC motors

UK supplier of FAULHABER motors, Electro Mechanical Systems (EMS), will be supplying the new FAULHABER magnetic AEMT-12/16 L absolute encoder. The product is the first multiturn absolute encoder released by FAULHABER, complementing the existing portfolio of single turn units.

As opposed to single turn absolute encoders, which can only measure the position of the motor shaft, multi turn encoders can also count the number of revolutions. This makes them ideal for applications measuring both the degree of rotation and the total number of rotations, as well as for measuring longer lengths of linear motion where using a linear encoder is not possible. 

The new AEMT encoder has a high single turn resolution of twelve bits (4096 steps) and a pre-set multi turn resolution of 16 bits (65536 revolutions), delivering effective commutation and motion control with smooth speed control.

The encoder can be combined with the B, BX4 and BP4 series of FAULHABER brushless DC motors, also distributed by EMS, to deliver absolute angle information.

A synchronous serial interface (SSI) with bidirectional serial synchronous continuous (BiSS-C) protocol transmits the position data from the encoder in real time.

With the included amplifying line driver, the controller interface can conveniently be positioned up to five metres away from the motor and encoder. 

The BiSS-C protocol is ideal for applications where high transmission speed, flexibility and minimal implementation effort are required. The design of the system means digital Hall sensors for commutation of the motors are often no longer needed.

The encoder can be powered by the main power supply, alternative energy storage or its backup battery. This is beneficial as, if the main power supply is switched off, the backup battery can provide enough energy to detect motor revolutions and alter the multiturn count accordingly.

Therefore, when the main power supply is switched back on, the count is still valid and a new reference run isn’t necessary.

“The new AEMT encoder system has a sophisticated design that makes implementation and running straightforward, even in a complex mechanical system,” said Stewart Goulding, managing director of EMS. “For example, unlike incremental encoders, absolute encoders determine absolute rather than relative positions, which means the absolute angle information is available immediately after switching on.

“The encoder ensures efficient operation of the motor and enables the use of sinusoidal commutation, which minimises torque ripple and provides smooth motion with precise motor control,” Goulding added.

“EMS supplies a range of small and medium DC motors, including the FAULHABER ranges compatible with the new AEMT encoder. As the sole UK FAULHABER distributor, our skilled engineers have extensive knowledge of their systems, and can work with customers to provide motor technologies at the forefront of industry that are an ideal fit for the intended application. 

“The addition of the new FAULHABER encoder builds on our already large range of leading motor technologies, providing a variety of cutting-edge options to our customers.”

Check Also

Inner or outer? Rotor position specification for miniature DC motors

To get the most from miniature motion technology, a key design specification is whether to …

Polycarbonate enclosures protect crane control architecture in corrosive atmospheres

Galvanising plants need heavy lifting capabilities, but these systems must be able to endure an …

Firmware enables faster drive-to-drive communication and more flexible exchange of CANopen process data

The COMBIVERT F6 and S6 drive controllers from KEB Automation are now available with new …