Week -2
1..AIM:TO MAKE SIMULINK MODEL FOR DOORBELL USING SOLENOID.
BLOCKS USED:PULSE GENERATOR,SCOPE, SIMULINKPS CONVERTER,P-S SIMULINK CONVERTER,SPST SWITCH,BATTERY,ELECTRICAL REFERENCES, MECHANICAL REFERENCES,SOLENOID BLOCK.
FLOW PROCESS:In pulse generator signalsaree generatedfor every 2 seconds to control the switch to do the ringbell.the generated signals are plotted and then converted to real time environment.then according to the signal the switch acts to control the flow of current to solenod. when the current is passed to the solenoid it generrates magnetic field to attract the ironn armature.
From the solenoid the motion is sensed using ideal motion sensor then the signals are converted to simulink phase to record motionof hammer.
OBSERVATION OF RESULT:From time plot we observe the time pulse is generated for every 2 seconds to control the switch in aspan of 50 seconds.
From velocity and position plots we observe that bell is rung for every 2 seconds in aspan of 50 seconds
2.THERMISTOR CONTROLLEDD FAN: USE THERMISTOR TO SENSE THE TEMPERATURE OF A HEATER.
BLOCKS USED: Thermistor, signal builder,contolled temp source, resistor, voltage sensor, voltage source, electrical and thermal references, scope, display,solver conf, constants.
THERMISTOR: IT is a device which measures the temperature its working is based on relationship between resistance and temperature. in simulink thermistor block which is available is a positive temperature coefficient thermistor so here resistance of thermistor increases or decreases with respect to the temp output is in the form of voltage and curr
PROCESS: controlled temperature source represents an ideal source of thermal energy that can maintain controlled temp differences regardless of heat flow rate.the temp differences is set by physical signal port. positive temp differences causes the temp at port B greater than the temp at port A
Thermistor is a type of resistor whose reistances is based on temp. a linear resistor is used to control the amount of current from the battery.T voltage sensor is used to convert the voltage measured between two points into physical signal and voltage source represents ac and dc. solver configuration is represent by connected simscape blocks requires solver setting information for simulation IT is put in local mode put manually. in this signal block is used to get temperature signal for the controlled temp source. THe temp of the heater is supplied to thrmistor to sense it to run the fan when temp is reaches the 298k we have to trigger the circuit withe some battery and there is no device to calculate thermistor resistance so we put some resistor to it inseries . the voltge sensor is attached across the resistor to calculate the voltage drop and this is given to switch as threshold value to start thefan.
observation from results: from 0 to 10 seconds fan is off because temp is below 298 k which is 293k after the 10 second goes to 300 k fan will turn on since it exceeds the 298k. After 30 seconds the temp goes to 296k so it will turn off because it is below 298k.