High-speed Frequency Converter for Low-voltage Manufacturing Spindles in Machine Tools

A compact frequency converter for low-voltage manufacturing spindles in machine tools
A compact frequency converter for low-voltage manufacturing spindles in machine tools

 

On behalf of a premium manufacturer of motor spindles SIEB & MEYER has developed a compact frequency converter for the sensorless operation of manufacturing spindles with asynchronous and synchronous motors in the low-voltage range.

Client requirements:

The client is a globally acting premium manufacturer of motor spindles. For the purpose of expanding his spindle series the client required a new, customized frequency converter that, compared to the existing solution, made higher output frequencies and easier handling possible. The construction volume of the new, high-power frequency converter should remain the same, though.

Since the client distributes only one product worldwide, the frequency converter must be able to cope with different mains voltages and frequencies as well as many different operational environments, for example, the household mains.

The frequency converter should flexibly operate manufacturing spindles with asynchronous and synchronous motors in the low-voltage range with a maximum operating voltage of 3 x 80 VAC. Due to the size of the spindles, there was not enough space to integrate an additional speed sensor. Therefore, the spindles must be operated without sensor.

The customized solution by SIEB & MEYER:

In order to enable worldwide use SIEB & MEYER has implemented a wide range voltage input with active power factor correction (PFC). A DC/DC converter limits the maximum output voltage.

Compared with the previously used drive solution SIEB & MEYER has managed to increase the output power from about 160 VA to 420 VA – with unchanged construction volume.

The control technology (hardware and software) of the new, customized frequency converter is based on the well-proven series SD2S. An existing plug-in operating terminal was integrated in the device and expanded with the client's additional requirements.

The most important details in short:

  • wide-range power input with PFC, 90..230 VAC, 50/60 Hz
  • integrated EMC filter for category C1
  • output: 3 x 0..80 VAC, 0..2,000 Hz, S1: 420 VA
  • integrated operating unit
  • sensorless operation of synchronous and asynchronous motors
  • automatic winding detection