Speed Control Of DC motor using half controlled bridge converter

A very basic model to understand the concept.

Bridge Type Single Phase Half Controlled Converter is used to contol the speed
of the DC motor.
Forward Voltage of T1,T2 is taken 0.
Pulse generator used is programmable type.
As the firing Angle is increased , output voltage of converter is decreased.
Output voltage of the converter = input voltage to the DC motor.
Increase in the firing angle will ultimately decrease the speed of the DC motor.
In Scope 1, speed is measured with respect to time.
In Scope 2, input waveform of AC voltage and and output of the half
controllred converter is shown.
DC motor :1.) Field winding is excited by DC voltage.
2.) Armature winding is excited by output voltage of converter.