Tools, application notes support motor control applications

Microchip Technology offers tools for dsPIC Digital Signal Controller (DSC).
By Control Engineering Staff February 12, 2009

Chandler, AZ– Microchip Technology has announced expanded support for motor control applications based on the dsPIC Digital Signal Controller (DSC). The company also announced two new motor-control software application notes available free for download: One shows how power factor correction (PFC) algorithms can be combined with sensorless motor-control algorithms on a single chip. The second demonstrates how to run an ac induction motor (ACIM) faster than its rated speed for a class of applications, to lower cost, save space, or reduce weight.
The dsPICDEM MCLV Development Board

(part # DM330021) is a new low-voltage brushless dc (BLDC) motor-control development platform supporting the dsPIC33F family of motor control DSCs. It evaluates and develops sensored or sensorless BLDC and Permanent Magnet Synchronous Motor (PMSM) control applications, and contains a three-phase inverter bridge circuit that drives a BLDC or PMSM motor using different control techniques, without additional hardware.
The board, capable of controlling motors rated up to 48 V and 15 A, supports multiple communication channels, such as USB, CAN, LIN and RS-232. It employs a processor-differentiated Plug-In Module (PIM) strategy to support dsPIC33F motor-control DSCs with different memory and pin configurations.
Microchip wants to provide the industry’s most robust product offering and associated infrastructure for motor control, said Rich Hoefle, marketing manager for Microchip’s Digital Signal Controller Division. The worldwide demand for improved power quality standards is driving the trend to add PFC to line-powered motor control applications, he added. Power quality can be enhanced by implementing PFC, and efficient control of a motor can be realized using sensorless Field Oriented Control (FOC) techniques. Both can be achieved by integrating PFC and sensorless FOC algorithms on a single dsPIC DSC.
Microchip’s Application Note 1208 describes the process of integrating these two complex functions in a PMSM application.
For sensorless field-oriented control of an ac induction motor using field weakening, the algorithm provides high torque at low speed and high performance, with lower torque at extended speed. It is suitable for any ACIM application to optimize torque per amp above the rated speed or the constant torque region of an ACIM. The strategy is described in Microchip’s Application Note 1206 , which provides source code for the dsPIC30F and dsPIC33F DSCs.
To reduce motor-control development time, users can now tune motor parameters in real time, eliminating the “stop motor/build/reprogram/run motor” development cycle, says Hoefle. The graphical Data Monitor and Control Interface (DMCI) in MPLAB IDE Version 8.15 has been enhanced to include a Real-Time Data Monitor (RTDM) function. Version 8.15 can be downloaded free online.
Microchip Technology

– Edited by Renee Robbins , senior editor
Control Engineering News Desk
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