Advancements In Eco-Design Strategies For Enhanced Motion Control Systems In Manufacturing

Nicola Sgambelluri, Engineering Manager, Pentair

Motion Control Systems (MCSs) play a crucial role across various sectors including industrial, automotive, aerospace, residential, and consumer applications. They facilitate complex movements, enhancing accuracy, reliability, and productivity in Manufacturing processes.

Recent European ecodesign legislation, transitioning from the Ecodesign Directive 2009/125/EC to the Ecodesign for Sustainable Products Regulation (ESPR), alongside corresponding standards set by the US Department of Energy (DOE), has clearly stated the importance of energy efficiency and environmental sustainability in MCSs. It’s widely acknowledged that electric motors and their applications account for approximately 60% of global electricity consumption. This underscores the need for strategies to align MCSs with the latest ecodesign requirements and regulations.

To optimize the MCSs, it’s essential to consider the following key points:

Efficient Motor Selection: One criterion involves selecting high-efficiency motors that meet international standards such as those defined by the International Electrotechnical Commission (IEC) or the National Electrical Manufacturers Association (NEMA). Motors with premium efficiency ratings can significantly reduce energy consumption. The adoption of Variable Frequency Drives (VFDs) enables optimal energy usage by adjusting motor speed according to load requirements, thus minimizing energy waste compared to constant-speed operation.

Regenerative Braking And Energy Recovery: Incorporating regenerative braking systems, where applicable, allows for the capture and conversion of kinetic energy from deceleration or braking into electrical energy. This energy can be fed back into the system, thereby reducing overall energy consumption. Energy recovery systems utilizing technologies such as flywheel energy storage or hydraulic accumulators enable the capture and reuse of energy that would otherwise be wasted during operation.

Intelligent Control Algorithms And Efficient Transmission Systems: Advanced control algorithms optimize system performance while minimizing energy usage. These algorithms, incorporating predictive maintenance techniques and real-time optimization, contribute to maximum efficiency. Optimization of transmission systems, such as gears, belts, and pulleys, minimizes energy losses due to friction and mechanical inefficiencies.

Integration With Energy Management Systems And Lifecycle Assessment: Integration of MCS with broader energy management systems allows for monitoring, analyzing, and optimizing energy usage across multiple processes or systems within an industrial facility. Conducting lifecycle assessments evaluates the environmental impact of MCS, enabling the design of products with disassembly and recycling in mind to minimize waste and maximize resource efficiency throughout their lifecycle.

"The evolution of MCSs towards enhanced energy efficiency and environmental sustainability requires a multifaceted approach encompassing efficient motor design and selection, enhancing VFDs through smart power modules and WBG semiconductor materials and integrating intelligent control algorithms"

From an engineering perspective, the process of designing or selecting the right motor hinges on the application, taking into account numerous factors such as size constraints, frame compatibility, control types and precision, as well as considerations regarding cost and energy efficiency. The most common types of electric motors used in manufacturing processes, AC Induction Motors (IMs) can be improved for energy efficiency through the utilization of VFDs. Permanent Magnet Synchronous Motors (PMSMs) and Switched Reluctance Motors (SRMs) offer higher efficiency alternatives, particularly in applications requiring very high efficiency or variable loads.

Considering the VFDs selection and their design, one of the recent trends is the integration of wide-bandgap (WBG) semiconductor materials such as silicon carbide (SiC) and gallium nitride (GaN) as power modules. These materials offer superior performance compared to traditional silicon-based devices in terms of efficiency, power density and switching speed. By leveraging WBG materials, power electronics designers can obtain more efficient and compact drives. Furthermore, integrated smart power modules simplify the VFD design and include additional functionalities such as temperature sensing, overcurrent protection and fault diagnostics, improving the reliability of the VFD.

Advancements in digital control techniques (DCT), e.g. Field Oriented, Direct Torque and Model Predictive Control algorithms allow high performance of electrical drives with smooth operations and better responsiveness. Pulse-width (PWM) modulation remains the dominant approach, offering precise control over the output voltage/current by varying the duty cycle of the switching signal, and controlling speed, torque, and/or motor position. Recent improvements focus on enhancing the performance of PWM techniques through strategies such as space vector modulation, predictive control, and hybrid modulation schemes. These techniques aim to minimize harmonic distortion, improve dynamic response and reduce electromagnetic interference in an MCS.

These sophisticated control techniques have become achievable due to the technological advancements in Systems on Chip (SoC) and Microcontrollers (MCUs). Complete motion control ecosystems designed for “real-time” control, capable of driving multiple motors are largely available in the market. These systems incorporate power management, industrial communication interfaces, HMI interface management, and security features.

Understanding these developments is essential for engineers and researchers to harness the full potential of power electronics in improving MCSs.

In conclusion, the evolution of MCSs towards enhanced energy efficiency and environmental sustainability requires a multifaceted approach encompassing efficient motor design and selection, enhancing VFDs through smart power modules and WBG semiconductor materials and integrating intelligent control algorithms. By implementing these strategies, MCS can meet the latest ecodesign requirements and regulations reducing simultaneously energy consumption, lowering operating costs, and minimizing environmental impact. Collaboration across industry stakeholders and regulatory bodies is essential to drive innovation and ensure continuous improvement in sustainable motion control technology.