Typical applications for ABB’s HDP motors include plastic and rubber extrusion systems, injection molding machines, winders, cranes and lifting devices, conveyor systems and test benches. They are also found in automation and machine tools, and even in roller coasters and ski lifts.
The motors – which are always used with a variable speed drive (VSD) - are available with IP23 and IP55 protection ratings, in frame sizes 80 – 400, and for supply voltages of 400 - 690 V. HDP motors are very well suited for applications that need to be converted from DC to AC technology.
The main features of HDP motors are their rectangular housing, light and robust construction, high dynamic performance, and excellent power-to-size ratio. The motors are extremely compact in design and offer a significantly lower moment of inertia than comparable standard motors.
Upgrading the homogenizer from DC to AC
Compact size was the decisive factor behind the choice of an ABB HDP motor for a homogenizer at the Straub Beauty Group cosmetics plant in Germany. Located in Wertheim am Main, around 70 kilometers southeast of Frankfurt, Straub manufactures high quality cosmetics, including shampoos, creams and other beauty products.
The homogenizer is at the heart of the production process. It mixes various components - such as carrier substances, solids and liquids - that are often difficult to mix. The products are manufactured in batches and then filled into cans, tubes or bottles.
The HDP motor was supplied by Lamb, an ABB partner company and distributor. Lamb is based in Würzburg and provides technical advice and support in upgrading production processes. Lamb serves a wide range of industries, including the pharmaceutical, cosmetics and food sectors.
Lamb had previously supplied ABB AC drives to Straub as a preventative maintenance measure. Andreas Dürr, an electrical engineer at Lamb, was responsible for replacing the existing drives with new ABB products and overseeing their commissioning.
Replacing the wear-prone DC motor
During homogenization, the various substances are kneaded, pumped and pressed to prepare them for further processing. The homogenizer was previously driven by a DC motor with a special shaft. This delivered the high breakaway torque necessary to ensure that the agitator could start safely, regardless of the amount and consistency of the material to be mixed. The motor speed is regulated in the range 500 to 3,000 rpm.
“One disadvantage of the DC motor was that its carbon brushes were prone to wear,” Andreas Dürr says. “This became a problem when the manufacturer ceased production of the motors and announced that technical support would no longer be provided. Any failure of the key system would seriously impact production, so we were asked to prepare a plan to upgrade the system.”
Andreas Dürr set out to design a new drive system to meet the actual requirements of the process. He created an operating profile for the equipment by recording speed and torque data. A fixed speed setpoint was entered in the drive and the associated motor speed was measured with a stroboscope. A data logger was set up to record the speed setpoint, together with an energy meter to measure current and power. The right motor and drive were then selected using ABB's DriveSize software tool.
The optimal solution proved to be an HDP motor with a special shaft and an ACS880 drive. As Dürr explains: “An HDP motor provides many benefits. It dissipates heat well and is a cost-effective alternative to a DC motor. Its compact size makes it ideal for places with limited space, and it can also deliver very high maximum speeds.”
The motor’s high dynamic performance is not required for the homogenizer, but a standard motor could not be used due to the limited space available.
The existing DC drive was located in a control cabinet on an elevated walkway. In summer it was subject to high ambient temperatures, as the sun heated the plant’s metal roof. An ACS880 drive with an IP55 protection rating was selected so that it could be installed outside the control cabinet, which helps to keep the temperature in the cabinet lower. High control precision is ensured by the motor’s rotary encoder and the drive’s DTC (Direct Torque Control) feature.
Fast response following downtime
Shortly before the motor was delivered, the plant experienced an unexpected stoppage on the homogenizer. Lamb acted very quickly, contacted ABB and requested express delivery for the equipment. Items that were immediately available, like the drives and cables, were delivered in advance so that work could start early.
The new motor was installed overnight. The next morning, Andreas Dürr was on site to check that everything had been correctly installed and connected, and he input the necessary parameters and optimized the drive. To avoid the risk of another failure, Straub ordered a second, spare HDP motor. The three-phase HDP motor with drive has clear advantages over DC motors in terms of maintenance intervals and reliability. It has been running trouble-free since it was commissioned, and the end customer has been satisfied with its performance.
To learn more about ABB’s HDP motors, click here.
Frank Wesseler is Product Marketing Manager, IEC LV Motors at ABB Motion in Germany.