Modeling (Motor & Fan) in Spice?

[Dale Chisholm]

Has anybody come across Spice models for a motor-driven blower or fan?
I have models for small motors, wher (to a first approximation) motor
speed is proportional to terminal voltage and shaft torque is
proportional to armature current. But I have a data sheet for a
blower, with a performance curve relating air flow rate (cu ft/min) to
back pressure (inches of H2O). I can easily measure terminal
charcteristics (voltage and current) with the air path either
completely open or fully blocked. Now - how do I couple this
information together to relate the electrical characteristics to a
given flow/pressure situation?

Thanks -
Dale

 

[qrk]

On 3 Dec 2003 10:05:51 -0800, dtchisholm@yahoo.com (Dale Chisholm)
wrote:

Has anybody come across Spice models for a motor-driven blower or fan?
I have models for small motors, wher (to a first approximation) motor
speed is proportional to terminal voltage and shaft torque is
proportional to armature current. But I have a data sheet for a
blower, with a performance curve relating air flow rate (cu ft/min) to
back pressure (inches of H2O). I can easily measure terminal
charcteristics (voltage and current) with the air path either
completely open or fully blocked. Now - how do I couple this
information together to relate the electrical characteristics to a
given flow/pressure situation?

Thanks -
Dale

Perhaps you can enter data into a table. PSpice and LTspice have such
support for voltage-controlled voltage source (E) and
voltage-controlled current source (G). The table data is interpolated
during the sim. Only good for AC analysis.

Mark

 

[Jim Thompson]

On Wed, 03 Dec 2003 17:25:32 -0800, qrk <mark@reson.DELETE.ME.com>
wrote:

On 3 Dec 2003 10:05:51 -0800, dtchisholm@yahoo.com (Dale Chisholm)
wrote:

Has anybody come across Spice models for a motor-driven blower or fan?
I have models for small motors, wher (to a first approximation) motor
speed is proportional to terminal voltage and shaft torque is
proportional to armature current. But I have a data sheet for a
blower, with a performance curve relating air flow rate (cu ft/min) to
back pressure (inches of H2O). I can easily measure terminal
charcteristics (voltage and current) with the air path either
completely open or fully blocked. Now - how do I couple this
information together to relate the electrical characteristics to a
given flow/pressure situation?

Thanks -
Dale

Perhaps you can enter data into a table. PSpice and LTspice have such
support for voltage-controlled voltage source (E) and
voltage-controlled current source (G). The table data is interpolated
during the sim. Only good for AC analysis.

Mark

A motor is a VCO (Kv/s).

Add some elements in parallel with the "control voltage" to model
loading.

(Mark: "Table" can be used in *any* type of simulation.)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

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