X-Factors

1. Overview

The X-factor panel allows the user to defined calibration factors to tune the thermal modeling on specific resistances.

The adjustment factors set in this panel are considered in the results shown in “external cooling” environment, and in the test environment.

The X-factor panel also contains a set of parameters driving the external cooling (coolant temperatures and rotor speed) allowing the user to evaluate the thermal model embedded.
External cooling – X-factor area
1 Display the axial and radial view of the machine
2 Display the external cooling datasheet, showing the main thermal parameters of the frame cooling.
3 Radial view of the motor, where specific exchange areas can be highlighted depending of the selected input.
4 Axial view of the motor, where specific exchange areas can be highlighted depending of the selected input.
5 The section X-Factor is selected.
6 Table of the calibration factors allowing the user to tune the thermal modeling.
7 Input table used for evaluating the external cooling, driving the results displayed in the external cooling datasheet.
8 Button to restore default input values.
9 Button to apply inputs. Pressing the enter key twice applies inputs too.
10 Icon to export external cooling data into *.txt or *.xls files.

2. Calibration factors
External cooling – Calibration factors input table
1

Frame-cooling circuit resistance.

This calibration factor is applied on the thermal resistance linking the frame and its cooling circuit.

This X-factor exists only when a cooling circuit is defined by the user in the MACHINE subset, HOUSING panel, CIRCUIT setting.
2

Frame-external fluid resistance.

This calibration factor is applied on every resistance linking the frame and the external fluid:

· Conduction resistances through the frame and end cap thicknesses

· Natural and forced convection resistances

· Radiation resistances from the external surfaces of the frame and of the end caps, to the infinite

3. Model evaluation
External cooling – Model evaluation input table
1

Machine maximum speed.

It is the maximum rotation speed for which the forced convection is evaluated in the external cooling datasheet
2

Cooling circuit temperature.

It is the temperature used in external cooling panel to evaluate the convection occurring in the cooling circuit.

All the results shown for the cooling circuit in external cooling panel and datasheet use this temperature as the temperature of the coolant all along the circuit.

This parameter only exists when a cooling circuit has been defined by the user in the MACHINE subset, HOUSING panel, CIRCUIT setting.

Note: This temperature is only used for the model evaluation in the external cooling panel. This temperature does not affect the test computations, where the cooling circuit coolant inlet temperature is defined in the settings of the test.
3

External fluid temperature.

It is the temperature used in external cooling panel to evaluate the convection and the radiation occurring on external surfaces of the frame and of the end caps.

All the results shown for frame and end caps cooling in external cooling panel used this temperature as the temperature of the external fluid at the infinite.

The curves and maps are plotted for a temperature of the frame going from this reference temperature to 150 Kelvin above this reference temperature.

Note: This temperature is only used for the model evaluation in the external cooling panel. This temperature does not affect the test computations, where the external fluid temperature is defined in the settings of the test.