This information is part of the Modelica Standard Library maintained by the Modelica Association.

Test example: Series excited DC machine at single-phase AC voltage started with a series resistor
At sinusoidal source voltage, a series resistor limiting the armature current, is reduced according to a ramp, causing the DC machine to start, and accelerating inertias against load torque quadratic dependent on speed, finally reaching nominal speed.
Simulate for 2 seconds and plot (versus time):

• dcse.ia: armature current
• dcse.wMechanical: motor's speed
• dcse.tauElectrical: motor's torque

Default machine parameters of model DC_SeriesExcited are used.
Note:
Since both the field and the armature current are sinusoidal, the waveform of the torque is the square of sine. Due to the additional inductive voltage drops, output of the motor is lower, compared to the same motor (DCSE_Start) at DC voltage.

Va	Value: 100 Type: Voltage (V) Description: Actual armature voltage RMS
tStart	Value: 0.1 Type: Time (s) Description: Start of resistance ramp
tRamp	Value: 0.9 Type: Time (s) Description: Resistance ramp
TLoad	Value: 63.66 Type: Torque (N⋅m) Description: Nominal load torque
wLoad	Value: 1410 * 2 * Modelica.Constants.pi / 60 Type: AngularVelocity (rad/s) Description: Nominal load speed
JLoad	Value: 0.15 Type: Inertia (kg⋅m²) Description: Load's moment of inertia
dcseData	Value: Type: DcSeriesExcitedData Description: DC machine data