Week -2
Objective:
Make a Simulink model of doorbell using Solenoid block.
Sense the temperature of a heater & turn on or turn off the fan using Thermistor.
Theory: #Part 1 doorbell:
The doorbell is a device having mechanical and electrical component produce sound on pressing the button.
When the switch is pressed, the circuit loop is complete which causes the current to flow through the circuit, while passing the Solenoid it generates the electromagnet at desired space, which allows the plunger to move, due to which it hots the bell and produce sound.
Explanation:
In Simulink, we use blocks to represent any system to get the desired output. In this project, we use some blocks to get our desired output.
1. pulse generator: The Pulse Generator block generates square wave pulses at regular intervals. The block waveform parameters, Amplitude, Pulse Width, Period, and Phase delay, determine the shape of the output waveform.
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Simulink-PS Converter: It Converts the Simulink input signal into a physical signal.
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Switch: Switch controlled by an external physical signal.
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Battery: It gives the power to the close loop.
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Electrical reference: It shows Connection to electrical ground.
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Solenoid: Electrical characteristics and generated force of solenoid.
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Ideal translational Motion Sensor: It is a motion sensor in mechanical translational systems.
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PS-Simulinlk Converter: It Converts physical signal into Simulink output signal.
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Mechanical Translational References: Reference connection for mechanical translational ports.
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Scope: It displays signals generated during simulation.
#Part 2:
Thermistor: A thermistor is a resistance thermometer or a resistor whose resistance is dependent on temperature. Condition:
Temperature source: 20 °C from 0 to 10 seconds, 27 °C from 10 to 30 seconds, 23 °C from 30 to 50 seconds Fan conditions: ON if the temperature above 25 °C, OFF otherwise.
Explanation:
As per the given condition for time and temperature give the values to the signal builder and configure as per our condition.
There is a Simulink-PS converter that converts Simulink signal to Physical signal.
Give this signal to The Controlled Temperature Source block which represents an ideal source of thermal energy that is powerful enough to maintain specified temperature difference across the source regardless of the heat flow consumed by the system.
This signal then passes to Thermistor which connected to the battery.
The voltage sensor is connected to a resistor which is used to measure the voltage as a threshold value for the condition of our circuit.
As per Fan condition that ON if the temperature above 25 °C, OFF otherwise. We use the switch and provide a threshold value.
If the signal value is greater than the threshold value then turn it On otherwise it will be turned Off.
The Angular Velocity graph shows that if the temperature is 20 deg. Celcius (293 K) the fan is off for the first 10 sec when the temperature reaches 25 deg. Celcius (300 K) then the fan is for the next 20 sec and when the temperature comes to 23 deg. Celcius (296 K) fan gets off.
Conclusion:
In this way, In the first part, we use Solenoid to convert electrical energy into mechanical energy and made a Simulink model into a doorbell.
In the second part, we use the thermistor to sense the temperature, and according to the given condition, we put the threshold value to the switch for turn On and turn Off the fan.