New and existing stepper motor applications will benefit from SILENTstep, a sensorless drive and control system developed by Agile Systems and available in the UK from LG Motion. The new modular drive combines patent-pending sensorless commutation with an advanced stepper drive and motion control platform for a significant increase in motor speed and useable torque with up to 75% less audible noise.
Unlike conventional, open loop stepper systems which have a tendency to stall when over accelerated or when torque demand is irregular, SILENTstep actually offers stall prevention and detection and has the ability to accelerate and decelerate at maximum torque with no position loss. It is estimated that a minimum two-fold performance increase is possible against an open loop stepper motor and drive system.
SILENTstep essentially increases stepper motor operation into the range of servomotor performance and for existing applications could have enormous benefit across many application areas by significantly improving production throughput without the need to replace in-situ stepper motors.
The new encoderless/sensorless drive also offers much lower levels of mechanical resonance, making it suitable to replace conventional stepper drives to meet stringent noise level regulations for sensitive medical and laboratory equipment.
For new applications, SILENTstep will allow designers to build in high efficiency, closed loop positioning systems with whilst maintaining the inherent simplicity and low installation costs of a conventional stepper motor drive system. To maintain a required level of performance, motor sizes may be reduced with space saving and added efficiency advantages; and with less components to specify, design time, selection and inventory costs are further reduced.
SILENTstep is available with 15 to 75 VDC input voltage and a 7 A peak current rating. Inputs are provided for differential pulse and direction with an opto-isolated enable input and opto-isolated outputs for faults and stall. An RS 232 oport is also provided for set-up and troubleshooting. An evaluation kit version is available for customers wishing to explore the enormous potential of the product.
For motor set-up, tuning and configuration, Agile's DP·SS is a Windows based application software that is used to automatically close the motor current loop and determines the no-load servo control parameters. With I/O and fault status display, the software may be used in a virtual mode to access the integrated help system. Parameters may also be saved to a downloadable configuration file.