Chips and Modules
Today’s factories rely on robotics and automated systems more than ever. These industrial systems require sophisticated and reliable motion control electronics to work properly. A variety of chip- and module-based solutions are smoothing the way.
Technology for providing industrial motion control continues to advance, as chip- and board-level solutions evolve to meet new requirements. An important piece of today’s connected industrial IoT systems, motion control involves mixing signal processing to enable accurate, real-time motor control, with precise analog technologies to control position, torque and speed.
To address all those demands, makers of chip- and module-based motion control products have rolled out new solutions over the past 12 months. These range from rugged, highly integrated servo control modules and motion control boards, to enhanced microcontroller (MCU)-based solutions with hardware and software aimed at solving motion control challenges.
MOTOR CONTROL ECOSYSTEM
Electric motors are proliferating across a growing range of system applications, including industrial systems. Targeting such needs, in October, Microchip Technology rolled out an expanded its motor control offering with digital signal controllers (DSCs) and MCUs that are supported by design tools, development hardware, a torque-maximizing algorithm and a refrigerator compressor reference design (Figure 1).
Several products make up Microchip’s expanded motor control family. First, are the dsPIC DSCs. These are cost-optimized, functional safety-ready dsPIC33CK64MC10x DSCs for field oriented control (FOC) are supported by motor control Plug-in Modules (PIMs) for existing motor control development boards and also with a new cost-effective low-voltage motor control development board.
Second is the PIC32MK MCJ and MCM MCUs for FOC. These second-generation 32-bit MCU devices offer 32-bit floating point and DSP performance with flexible communications options. By sharing analog features with the dsPIC33CK, they support seamless migration across device classes. These devices also feature multiple CAN-FD and USB ports.
The third offering is the motorBench development suite, version 2.35 of Microchip’s GUI-based software development tool. The software shortens the time required to spin a motor using FOC and generates optimized source code customized for a given motor. This release expands dsPIC33CK family support, adds a new Angle Track-Phase Locked Loop (AT-PLL) estimator, Field Weakening (FW), Maximum Torque Per Amp (MTPA), Dead-Time Compensation (DTC) and many other new features.
Also part of the new motor control ecosystem is the Zero Speed/Maximum Torque (ZS/MT) algorithm. This eliminates hall sensors in applications demanding high torque at standstill or low speeds for low-inductance motors. Support is provided for the dsPIC33 DSCs, SAM and PIC32MK motor control MCUs.
Rounding out the set of products is the dsPIC33CK Low-voltage motor control development board. It provides a platform for application development and a reference for customer board design for the dsPIC33CK family. And finally, Microchip offers a low-cost, high-efficiency refrigerator compressor reference design, showcasing practices for an application-specific motor control design.
MOTION CONTROL MCU
MCUs are also a key part of today’s industrial motion control story. Along those lines, earlier this year, Infineon Technologies released its IMC300 motor controller series. It combines the iMOTION Motion Control Engine (MCE) with an additional MCU based on the Arm Cortex-M0 core (Figure 2). IMC300 complements the IMC100 series and aims at variable speed drives that require very high application flexibility. Both families, IMC100 and IMC300, share the same implementation of the MCE 2.0 providing ready-to-use motor and, optional PFC control. Applying the MCE for controlling the motor, customers can focus on their system application that runs fully independently on the embedded Arm MCU.
Infineon’s field-proven MCE 2.0 implements highly efficient FOC of permanent magnet synchronous motors (PMSM). The MCE integrates all required hardware and software building blocks as well as all necessary protection features resulting in a reduced bill of material (BOM). It undergoes continuous improvements with typically two releases per year. The autonomous MCU offers a flexible peripheral set and can serve a multitude of purposes like system functions, specific communication or drive monitoring. IMC300 devices are pre-certified for applications requiring functional safety according to UL/ IEC 60730 (Class B).
IMC300 derivatives are offered for motor drives with and without PFC control. Devices in LQFP-64 packages (shown) are in mass production, and LQFP-48 types will be released in the second quarter 2020. Rapid prototyping of a drive inverter is enabled via two new control boards for the iMOTION Modular Application Design Kit (MADK). MADK is a modular and flexible development platform providing a range of control and power board options for motor drive applications up to 1kW.
Yet another MCU vendor providing new solutions for motion control is Renesas Electronics. In April, Renesas announced its RX72N Group and RX66N Group of 32-bit MCUs, new additions to the RX Family that combine equipment control and networking function on a single chip (Figure 3). Built around the Renesas proprietary RXv3 CPU core, the RX72N features a maximum operating frequency of 240MHz and two Ethernet channels, and the RX66N features a maximum operating frequency of 120MHz and one Ethernet channel.
Among the key features in the MCUs is a hardware accelerator for faster motor control. The RX72N Group and RX66N Group incorporate an arithmetic unit for trigonometric functions (sin, cos, arctan, hypot; RX72N only) that accelerates motor vector control and a register bank save function that decreases the interrupt response time. This reduces the CPU load required for closed-loop control and simplifies the implementation of additional functions such as networking capabilities.
According to Renesas, in the industrial equipment market, performance and functionality improvements lead to larger program code sizes. As a result, storage capacity and read speed play key roles in determining real-time performance. The new RX72N and RX66N devices offer up to 4MB of on-chip flash memory that perform read operations at a frequency of 120MHz, among the fastest in the industry, as well as 1MB of on-chip SRAM. This ample on-chip memory eliminates the need for external memory, which has slower read speeds, and makes it possible to extract the full performance capacity of the CPU.
In addition, larger memory capacity enables high-resolution graphics support, such as WVGA, on a single chip, which was not possible on earlier general-purpose MCUs. With this combination, the MCUs can implement single-chip equipment control and networking function, enhancing the real-time performance of applications such as industrial robots, general-purpose inverters, programmable logic controllers (PLCs), and remote I/O devices. They also make it possible to improve the exterior design and operability of a wide range of industrial automation equipment.
FIELD ORIENTED CONTROL
According to In July, Trinamic Motion Control, FOC (or vector control), has proven itself as the efficient way for driving motors at optimal torque and velocity. At one time, it used to be a demanding task to implement FOC, but now more and more engineers use dedicated servo controller ICs like the Trinamic’s TMC4671.
With all that in mind, in July, Trinamic Motion Control, now part of Maxim Integrated, announced the TMCM-1636 module (Figure 4). Developed for bigger drives up to 1000W and 60A RMS, the board is well suited for robotics, factory automation, manufacturing, industrial drives, medical equipment and more. The board embeds Trinamic’s TMC4671 and TMC6100 ICs. The new module achieves high-current loop frequencies to minimize current ripple, enabling powerful drives with extremely high dynamics. The TMCM-1636 cuts down development time and cost even further by offering a highly dynamic solution for powerful servo drives with integrated FOC.
Communication takes place via the CAN interface with either TMCL or CANopen protocol, with the TMCL version offering memory for up to 1024 commands for standalone operation. This can all be programmed using the easy and intuitive TMCL-IDE, Trinamic’s free programming environment for quick setup and tuning of designs to reduce development time.
Thanks to the dedicated FOC servo controller IC TMC4671 featured on the board, the TMCM-1636 allows for a wide range of feedback systems including two times ABN incremental encoder, analog encoder, digital Hall sensors, and SPI-based or RS422-based absolute encoders depending on the firmware option. The module also supports +5V DC supply for external sensors. Further custom firmware options enable specific absolute encoder types interfacing via SPI or RS422.
The stacked board features an aluminum bottom plate with a total of seven M4 screw terminals for effective cooling. On top, it features one IO and interface connector and one brake control output connector, allowing for compact designs with clean wiring. An integrated overvoltage protection output is added for additional safety to your device.
FUNCTIONAL SAFETY FEATURES
Ensuring safety is a critical requirement in any factory floor setting. Serving those needs, in September, Elmo Motion Control, announced the commercial launch of its Platinum series servo drives, featuring advanced servo functionality and functional safety capabilities.
According to Elmo, the new line is designed to meet OEMs’ growing needs for safer, smarter, smaller and faster servo drives with higher functionality. It is targeting applications requiring the highest-quality motion, in medical, robotics, material handling, semiconductor, laser processing, printing, and inspection, and for other applications in various industries.
The Platinum line features EtherCAT networking and processing, providing faster cycling and higher synchronization, with negligible jitters and near-zero latency (Figure 5). The higher processing power enables faster data handling, a larger memory and an endless real-time recorder, supporting high performance applications.
The Platinum servo drives hold the highest-level functional safety certifications (IEC 61800-5-2 SIL-3, Cat4 PL-e), and have a comprehensive set of smart functional safety features, including over-the-network safety and optional rich safety I/Os, supported by Elmo’s advanced safety software. The Platinum line includes one of the world’s smallest Functional Safety and Functional Safety over EtherCAT (FSoE)-certified servo drives.
The drives are fully synchronized to the servo loops and feature-rich feedback support, up to three feedbacks simultaneously (with two absolute encoders working simultaneously). The Platinum lines include one of the world’s smallest Functional Safety and FSoE-certified servo drives with unique SIL capabilities All servo drives of the Platinum series can easily be configured with the new EASII 2.7 software. The software enables EtherCAT configuration, motion configuration, drive tuning, parameter recording and much.
EXTENDED TEMPERATURE SUPPORT
The most recent offering from Advanced Motion Controls are its Extended Environment versions of its line of FlexPro servo motor drives. Extended Environment versions of both the PCB mount and machine embedded FlexPro drives are also available. According to the company, they offer all the convenience and power of the standard FlexPro drives, but they’re built to handle more extreme environmental conditions.
The Extended Environment FlexPro drives can operate in temperatures as low as -40°C to as high as +95°C (-40°F to +203°F), and their thermal shock resistance allows them to go from one end of that range to the other in just three minutes without any damage. They can also withstand 95% non-condensing humidity, pollution degree 2, and up to five minutes of 25 G (RMS) for in 3 axes. The devices are able to function at altitudes as high as 25,000 meters above sea level.
An example product in the FlexPro line is the micro-sized FM060-5-EM FlexPro drive with IMPACT architecture (Figure 6). The unit is an all-purpose digital servo drive for centralized or distributed control systems with EtherCAT communication. Its compact size makes it perfect for any application where space is a limiting factor. This drive is an alternate version of the FE060-5-EM, featuring convenient connectors instead of direct plug-in, so you can easily integrate it into any system.
Advanced Motion Controls | www.a-m-c.com
Elmo Motion Control | www.elmomc.com
Infineon Technologies | www.infineon.com
Microchip Technology | www.microchip.com
Renesas Electronics | www.renesas.com
Trinamic Motion Control | www.trinamic.com
PUBLISHED IN CIRCUIT CELLAR MAGAZINE • NOVEMBER 2020 #364 – Get a PDF of the issueSponsor this Article
Jeff served as Editor-in-Chief for both LinuxGizmos.com and its sister publication, Circuit Cellar magazine 6/2017—3/2022. In nearly three decades of covering the embedded electronics and computing industry, Jeff has also held senior editorial positions at EE Times, Computer Design, Electronic Design, Embedded Systems Development, and COTS Journal. His knowledge spans a broad range of electronics and computing topics, including CPUs, MCUs, memory, storage, graphics, power supplies, software development, and real-time OSes.