Press Release Summary:
With configuration software, users of MicroFlex single-axis drives can set up application-specific notch or low-pass filtering, which facilitate stiffer control. Available in power ratings of 3, 6, and 9 A, with 200% peak current capability, drives offer space vector modulation, synchronous serial interface, and incremental encoder feedback interfaces. They run from single- or 3-phase supplies from 115-230 Vac, and may be configured as torque or velocity reference.
Original Press Release:
BALDOR ELECTRIC's Brushless AC Servo Drive Adds Configurable Filtering to Combat Mechanical Resonance
Notch or low-pass filtering facilitates stiffer control - for higher machine productivity
Baldor has extended the versatility of its low-cost brushless AC servo drive, MicroFlex, with the addition of configurable anti-resonance filters. The software upgrade allows machine builders to implement filters to combat mechanical problems using the drive's DSP (digital signal processor) - providing a means of optimising machine productivity without additional expense.
A new configuration tool for MicroFlex single-axis drives allows users to set up application-specific notch or low pass filtering. Without this feature, machine builders will often be forced to de-tune a system with 'soft' servo loop gains. This can result in lower dynamic performance, longer settling times, and sometimes steady-state errors. The alternatives are tolerating the resulting noise and vibration - which is often impossible as it impacts production quality and potentially reduces life of mechanical system components such as bearings - or making mechanical changes such as adding additional mechanical dampening or modifying coupling components. If such mechanical changes are made during the development cycle, then time to market and the bill of materials can increase. If the problem is encountered during machine commissioning - a common scenario - then performance-reducing electrical changes are often the only practical solution.
The new software is a major complement to Baldor's MicroFlex range, because these new drives are specifically designed to help users realise higher machine throughputs. They incorporate advanced features to help users improve motor control and smoothness of motion, including space vector modulation (SVM), and high resolution synchronous serial interface (SSI) and incremental encoder feedback interfaces.
By controlling the IGBT power devices using SVM instead of the more usual carrier based pulse width modulation (PWM), users can run servo motors at typically 15% higher speeds with reduced switching losses and harmonics - which can translate directly into greater machine throughput.
SSI feedback can provide a similar boost to performance, by providing high resolution absolute positional data on every servo loop, enabling tighter control of velocity and positioning. This allows the low cost servo drive to be used in the highest precision applications, such as precision profiling or PCB assembly for example.
The MicroFlex servo drive also supports trapezoidal commutation, in addition to the usual sinusoidal commutation, allowing users to reduce hardware costs even further by employing an encoderless motor control loop with low-cost Hall-effect sensors. Such a configuration can be useful for linear motor control, as the required feedback devices and cabling can be more expensive than for a conventional rotary motor.
Baldor MicroFlex brushless AC servo drives are available in three power ratings of 3, 6 and 9A - with 200% peak current capability. They will run from single or three phase supplies from 115 to 230VAC, making it possible to fit one standard motion control system into machinery for international markets.
MicroFlex products may be configured as either a torque or velocity reference using the standard ±10V input command signal. For closed loop feedback packages, encoder, SSI or Hall sensors are supported. A step and direction interface is also supplied, making MicroFlex an ideal upgrade or replacement for stepper-based packages.
MicroFlex is a fully protected unit, and includes encoder loss detection, overcurrent, overvoltage, and overtemperature protection. With the addition of an external dumping resistor, regenerative braking energy can be dissipated.
Drives are configured for applications using Baldor's Windows software environment, Mint WorkBench. The same tool is used across Baldor's range of servo controls, intelligent drives and motion controllers, providing users who build a range of machines with a familiar configuration environment supported by a choice of hardware with common features. Mint WorkBench includes a sophisticated autotuning tool to help users install MicroFlex rapidly and efficiently. Custom filters are created using FFT analysis tools, and a simple intuitive dialogue which includes automated frequency response tests.
Baldor offers a comprehensive range of complementary products for MicroFlex, including NextMove multi-axis motion controllers in either PCB or boxed forms, and rotary brushless servo motors and linear motors.