Economical drive systems for modular machine automation
- Automation
- Drive Technology
- 17.6.2025
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Contents
Modular machine automation at a glance
The trend towards modularization has long since arrived in mechanical engineering. Modular machines enable shorter development times, greater flexibility in adapting to customer requirements and improved maintainability.
The modular design allows machine functions to be separated into logically and mechanically self-contained units. These modules can be developed, manufactured, tested and maintained independently. This shortens time-to-market times, increases flexibility and allows standardization potential to be exploited.
These modules can be easily networked with the help of modern real-time bus systems. Another important criterion for modularization is the decoupling of the energy supply from the control and drive technology. With suitable concepts, very energy-efficient and resource-saving machines can be realized.
Three basic forms have become established in practice:
- Modular machines with a central control cabinet
- Modular machines with decentralized control cabinets
- Machine modules without control cabinets
Each of these concepts places its own requirements on the drive technology – in terms of integration, cabling, energy efficiency, maintenance and scalability.
Comparison of modular machine and control cabinet concepts
Central control cabinets
This architecture is particularly common for classically designed machines or for manufacturers with homogeneous machine lines. All control components are housed centrally in a control cabinet. The electrical components in the machine modules are connected directly to the central control cabinet. The central control cabinet is usually connected to an AC supply network.
Advantages:
- A single access point for maintenance and service
- All components bundled together – simple wiring and diagnostics
- Ideal if all modules come from the same manufacturer
Disadvantages:
- Greater space requirements for the central control cabinet
- Higher energy consumption for cooling the control cabinet
Decentralized control cabinets
Decentralized automation concepts are becoming increasingly important, especially for heterogeneous machine architectures, e.g. if individual modules come from different manufacturers or are to operate independently of each other. Each module has its own control cabinet, e.g. with controller and drive.
Traditionally, all modules are connected to an AC supply network. For reasons of energy efficiency, modules and the drives installed in them are increasingly supplied via a DC network. For this purpose, a central AC/DC supply unit is installed in a small central control cabinet. A superimposed system or machine controller is then also located in this control cabinet.
Advantages:
- High flexibility in machine layout
- Independent commissioning of individual modules
- Parallel development by different partners possible
- Scalability through modular expansion
Disadvantages:
- Higher costs for multiple control cabinets
- More complex maintenance and diagnostics
- Potentially higher cabling costs
Machine modules without control cabinets
The most consistent form of modularization completely dispenses with central or decentralized control cabinets. The entire automation technology is integrated directly into the machine module – a particularly space- and energy-efficient solution.
Advantages:
- No enclosure cooling required – energy saving
- Minimal space requirement and reduced cable lengths
- Easier installation and project planning
- Quick adaptation and expansion of the machine
Disadvantages:
- Higher requirements for the protection class of the components
- More complex integration of control systems
- Potentially higher costs for decentralized drive systems
Suitable drive solutions for different degrees of modularization
The types of machine and enclosure modularization described above also require different drive solutions. In the following, we present various concepts with corresponding practical examples.
Drive solutions for central control cabinets
A multi-axis drive system is preferred for centralized control cabinets. This solution is compact and easy to install, economical for a large number of drives and energy-efficient thanks to the DC connection of the drives. KEBA offers KeDrive D3 here. KeDrive D3 is compact as it combines up to three axes in one power module.
Features of a multi-axis drive system:
- Compact solutions & easy assembly
- Economical with a large number of drives
- Energy-efficient with DC connection of the drives
- Central (intelligent) supply units
- Regenerative
- Power limitation & peak load reduction
- Integration of energy storage systems to increase grid reliability
Practical examples:
- A labelling machine with different drives for material feed, label feed and cutting uses KeDrive D3 centrally - for precise synchronization of all movements and minimal energy costs.
- In a corrugated cardboard production machine, KeDrive D3 takes over the drive control for the slitter and cross cutter, gluing station and stacking device - centrally, safely and energy-efficiently.
- A print finishing machine with a central control cabinet uses KeDrive D3 to operate several synchronized axes (e.g. feed, folding, cutting unit) in an energy-efficient and safe manner.
Drive solutions for decentralized control cabinets
When using decentralized control cabinets, the number of drive axes and also the power supply are decisive for the selection of a suitable drive solution.
A multi-axis drive system such as KeDrive D3 can also be used for decentralized control cabinets. However, it is only economical if a large number of axes per module is required. It also enables energy to be exchanged between several machine modules via the shared DC bus. However, it is also possible to use a separate AC-powered supply unit for each module.
Features of a multi-axis drive system with decentralized mounting:
- Economical with a large number (> 5) of axes per module
- Energy-efficient thanks to DC bus coupling of several control cabinets/modules
- AC or DC supply
AC-powered drive solutions in single or multi-axis design are suitable for small decentralized control cabinets or compact machines with fewer than 4-5 drives. These drives are so-called "All-in-one drive controllers". This means that in addition to the motor output stage, they also integrate an AC supply, a mains filter, brake chopper and also the brake resistor. KeDrive D3-AC and KeDrive D5 are such drive systems. KeDrive D3-AC offers up to 3 axes in one module, while KeDrive D5 offers a single-axis drive for AC low voltage and KeDrive D5 Micro one for DC safety extra-low voltage.
Features of drive controllers for small decentralized control cabinets:
- Compact "All-in-one drives" with AC supply
- Protective extra-low voltage drive controllers with a DC supply of 24 V - 48 V
Practical examples:
- In a modular assembly line with individual robot modules, each module is supplied by its own control cabinet with KeDrive D3-AC. The simple commissioning and modular expandability enable flexible production adaptations.
- Each machine in a sheet metal processing line (e.g. punching, laser cutting, bending, stacking) has its own control cabinet with a large number of drive axes. The KeDrive D3 multi-axis drive system is used here. The machines are supplied either energy-efficiently via a DC bus or separately via an AC power supply.
- In a compact modular production line, a separate module with KeDrive D5 is used for each station (e.g. screwing, gluing, testing). This allows the line to be expanded or reconfigured according to production requirements - without interfering with the overall structure.
- An automated guided vehicle system (AGV) for production logistics integrates several KeDrive D5 Micro directly in the vehicle. The drives are powered via a battery-powered DC/DC converter. The compact design enables a lean construction.
Drive solutions for machine modules without control cabinets
Drive solutions with a high degree of protection (e.g. IP65) are used for machines without control cabinets. The drive electronics are either installed directly in the motor or placed close to the motor. The drive power of these solutions is limited to the lower power range (rated currents < 20 A) due to thermal restrictions.
Various supply concepts (AC, DC) and voltage variants (e.g. 48 V DC, 400 V AC) allow adaptation to the process.
Motor-integrated drive solutions are very compact and highly integrated. However, they have the disadvantage that the space required around the motor increases due to the integration of the electronics. In addition, this solution is not as resilient as the classic servo motor, as the permissible temperature range is limited. So if you want to use a standard portfolio of servomotors or if the installation space for the motor is limited, then drive controllers that are mounted close to the motor are suitable.
Features of drive solutions for modules without control cabinets:
- Protection classes from IP54
- Energy-efficient DC supply
- Flexible daisy-chain device connection that integrates all signals in a hybrid cable (e.g. supply, fieldbus, safety)
For this type of modularization, KEBA offers open system solutions for the integration of third-party drive solutions. This is advantageous, as there is a wide variety of decentralized drives on the market that differ significantly in terms of design and connection technology. This variance is necessary as the drive solutions are installed directly in the machines, where attention must be paid to mechanical suitability.
As part of the successfully completed DC-INDUSTRIE research projects, a system concept was developed that makes it possible to connect products from different manufacturers to a common DC bus. The system concept is available from the ODCA under Updated system concept for DC-INDUSTRIE2 published. KEBA was a member of the research association and is now a member of the ODCA. Connection and protection concepts have been developed for the KeDrive D3 multi-axis drive system that make it possible to connect and operate additional products to the common DC bus in accordance with the DC-INDUSTRIE system concept.
Practical examples:
- A processing machine contains high-power drives and various additional modules for format adjustment or loading and unloading. The large drives are installed in a central control cabinet in the form of the KeDrive D3 multi-axis system. The additional modules are equipped with decentralized drives and supplied via the DC bus of the multi-axis system.
- A secondary packaging system consisting of a variable number of Delta robot cells has a very large surface area. Decentralized drives mounted close to the robots greatly reduce the amount of cabling required. The number of cells can be changed quickly by daisy-chaining the axes.
What is important now? What do I have to pay attention to?
There are many aspects that need to be considered when planning a machine. We recommend considering the following points at the start.
Think modular – implement uniformly
Despite different mechanical and electrical requirements, KEBA pursues a consistent platform approach. This means for designers and developers:
- The same interfaces for encoders, motors and I/O across all systems
- Identical safety concept (Safe Torque Off, SIL2/3, PL d/e)
- Standardized commissioning and diagnostic tools
- Compatibility between drives within a machine project
- Simple scaling from individual drives to multi-axis systems
What this means in practice:
- Reusability of engineering data
- Less training for developers and service technicians
- Minimal spare parts inventory despite a large number of variants
- Consistent system integration across all modules
Energy efficiency and sustainability
One aspect of modular machines that is often underestimated is energy distribution. KEBA focuses on centralized and decentralized concepts:
- DC link coupling with energy recovery
- Integration of regulated energy storage systems to increase grid failure safety as short-term storage for generator or motor peak loads, Peak load limitation (peak shaving) and controlled restart strategies
For decentralized or mobile applications in particular, these functions are crucial for reducing grid utilization and costs – while ensuring maximum availability.
Safety at all levels
Safety is a must in modular machines with moving axes. KEBA meets the highest requirements with:
- Safe Torque Off (STO) as standard in all devices
- SafeMotion functions (SIL2/3, PL d/e) for safe monitoring of position, speed and acceleration, among other things
- Safe fieldbus communication
- Integration in safety PLC environments via common protocols
Support in the selection of suitable drive components
The selection of a suitable drive system is often complex due to the large number of available components, technical dependencies and compatibility requirements. The KeDrive Configurator is available to structure and simplify this selection process.
It enables a systematic compilation of all required drive components – from servo controllers and motors to accessories – taking technical compatibility into account. The user-friendly interface and clear structure of the configurator help users to make a step-by-step selection, making it easier to find the right solution. Additional functions such as automatic quotation generation and 3D visualization also contribute to the clarity and reliability of the configuration.
