Battery Manufacturer Case Study – Siemens S210 Servo Drive

Not all systems integrators are created equal.  Apart from raw talent within the organization, the industry concentration of the firms varies. Some are good at process control; some specialize in food and beverage and others are adept at creating customized assembly machines, like what may be employed to assemble a ballpoint pen.  While EDC has performed projects in a wide spectrum of fields, tension control is where we shine.

Recently, EDC worked with a battery manufacturer to introduce specialized automation into an extremely delicate web handling process. Finding ways to integrate intelligent control solutions on an existing prototype process platform was a key concern for this battery supplier, who was working on mass-producing a successful battery R&D project.

The Challenge

As most battery manufacturing processes go, this one involves many steps – from slurry mixing and calendaring to slitting, coating and laminating. Particularly challenging was a web handling process necessary to laminate several substrates together, some as thin as 25 microns (um) – half the thickness of a human hair! A backing needed to be stripped off the substrate, then adhesive is applied, followed by the melding of the two very thin substrates together. Obviously, complex motor/torque control was necessary for delivering four things:

  1. Superfine tension control
  2. High reliability
  3. High stability
  4. High versatility

Note that EDC’s usual web handling applications realize tensions in excess of 100 times higher.  The customer also asked EDC to size all the motors based on their existing mechanical configuration. Further escalating the challenge, two other design constraints included 208VAC single phase input and space limitations to house nine total drives, a PLC, and associated controls.

The Solution

While relatively new on the market, the Siemens S210 servo drive was an obvious choice.  Compact, (footprint just 55 mm wide by 170 mm high or 2.2” x 6.7”), safe (EN 61508 & ISO 13849-1 compliant), and available in the requisite 208VAC single phase input (see Figure 1).

Battery Substrate Laminator Controls
FIGURE 1: Battery Substrate Laminator Controls Enclosure – featuring compact electrical design

 

In addition to delicate tension control, very fine speed control was needed. To address this aspect, EDC sized 20-to-1 and 50-to-1 planetary gearboxes for the nip and rewind motor sections.  Therefore, precise tension control could be accomplished with minute speed changes of the spindle motors.

The Solution Beyond-the-Drive

While we may be best known for our incredible drive expertise, EDC understands the intricacies of inline/web processes. Like other web lines, this machine uses “dancers” – i.e., feedback devices that help determine if the web is going too fast or too slow, thus affecting tension. Generally, dancers exert a predetermined force on a web that results in a desired tension, usually with an air cylinder and a pressure regulator commanded from the PLC, an “I-to-P” current-to-pressure device.  In some instances, weights on a lever arm are utilized with a high-quality potentiometer or encoder feeding back the position of the lever arm.  In the case of the battery laminator and its unique requirements, the traditional methods were not viable.

EDC’s unique solution utilized the Siemens S-1FL6 servo motors with Siemens V90 positioning amplifiers to directly drive the dancers.  The servo motor was commanded in a position mode at a percentage of its available torque. This placed the dancer arm at a location and force that corresponded with the desired web tension.  A fluctuation in the position of the dancer arm was detected by the dancer servo motor’s encoder and fed back to the PLC.  Siemens’ ProfiNet communications protocol was utilized to command the roll motors to speed up or slow down, thus maintaining the ultra-fine tension needed to peel the backing off of the substrate without damaging the web.

The Value of EDC’s Solution and Siemens S210 Drives

Using best-in-class technology and savvy drive programming, we were able to take a completely custom mechanical configuration and adapt a control system to that configuration. The end result was control of feather-light tensions and a machine capable of continuously peeling backing and laminating substrates using a fully-automated, scalable solution.

It is also important to highlight the value of the Siemens S210 drives. The power levels were low, the motors relatively small, and control was of critical concern. The agile S210 was well-suited for this battery laminator project and can be utilized for many other applications such as pick-n-place devices, metering pumps, and dynamic positioning tasks of all types.

Are You Ready to Embrace the Future of Manufacturing?

With buzzwords like “Industry 4.0” seeping into the manufacturing ecosystem, the pressure to automate can be overwhelming, but the benefits are enormous. Reducing manual touchpoints and increasing throughput throughout your entire manufacturing process can help you remain a competitive player in the global supply chain.

Are you looking for custom control and drive solutions that can help you automate those pesky hard-to-configure manufacturing tasks?

 Do you have an existing system that is need of a new lease on life?

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EDC’s custom integrated solutions can help you realize the power of automation in every layer of your manufacturing process.