Duty

Introduction

The Duty – Settings are un unlocked when the thermal solving is selected in the Thermal – Settings.

Standard duty types are available and the corresponding thermal limit analysis can be computed.

This brings together electromagnetic and thermal simulation by enabling users to visualize temperature maps over the entire operating range of a motor under standardized duty cycles (S1, S2, S3). The feature provides deep insight into the thermal limits of the machine that are critical for optimizing reliability, cooling strategies, and motor performance in real-world industrial applications.

Users will find the following key functionalities:

Standard Duty Cycle Integration: users can select from three commonly used IEC-standard duty types

S1 (Continuous)

With the S1 mode, a single point must be defined. The targeted working point must be defined with:
The mechanical torque
The Speed
Operation time:
- Auto mode: The calculation duration is determined automatically to allow the temperature to reach its steady state.
- User mode: The user can set the operation time value.

S2 (Short-Time)

With the S2 mode, a single point must be defined. The targeted working point must be defined with:
The mechanical torque
The Speed
Operation time: The user can set the operation time value.

S3 (Intermittent Periodic)

With the S3 mode, a single point must be defined. The targeted working point must be defined with:
The mechanical torque
The Speed
Cycle duration T
Cycle duration factor = ratio between T1 and T.
Number of cycles:
- Auto mode: The number of cycles is determined automatically to allow the temperature to reach its steady state.
- User mode: The user can set the number of cycles.
Temperature maps: two choices are possible:
- "On load"
- "Rest"

Note: Temperature Map Generation:

For each torque-speed operating point, the motor is simulated under the chosen duty.
At the end of the duty pattern, the steady-state or cycle-end temperature is recorded.
A complete thermal map is produced, visualizing hot zones and thermal risks.

Note: Auto Mode Support:

For S1 and S3, automatic cycle duration estimation is available based on the thermal time constant of the machine (typically 5× time constant), ensuring sufficient time to reach steady-state or periodic stability.

Note: Temperature Evolution Curves:

Users can select any working point to plot temperature vs. time, enabling assessment of heating and cooling dynamics across different duty profiles.

S9 (user-defined mode)

In addition to the previous IEC-standard duty types a user-defined one (S9 mode) can be defined.

Figure 4. New Duty settings with the four choices S9, S1, S2, and S3

User working point(s) analysis = Duty cycle

This allows computing the machine performance all over a customized duty cycle.

This duty cycle must be defined by using the field: "Duty cycle description" and by clicking on the button "Set values" (index 1 in the image above)

Two ways are possible to fill in the table: either filling in the table line by line or by importing an excel file which all the working points of the duty cycle are defined.

Note: A working point is defined by a time, a speed, and a mechanical torque.

Note: Once the test results have been computed, new user working point and duty cycle values can be set, and results will appear instantaneously when relaunching the test.

Table 1. User working point analysis = Duty cycle – Dialog box to define the duty cycle

1	Dialog box opened after having clicked on the button “Set values” in the field “Cycle description”
2	Browse the folder to select an Excel file which describes the duty cycle
2.1	Excel file template to define the duty cycle
3	Button to refresh the table data when the considered Excel file has been modified
4	Fields to be filled with data to describe the duty cycle to be considered.
5	Validate the data inputs
6	Erase the data table

Note: The Excel template used to import a duty cycle is stored in the folder Resource/Template in the installation folder of FluxMotor.