International Journal of Advance Engineering and Research Development Scientific Journal of Impact Factor (SJIF): 4.72 Special Issue SIEICON-2017,April -2017 e-issn : 2348-4470 p-issn : 2348-6406 Wireless Control of Dc Motor Using RF Communication Shah Parth 1, Kamaliya Haresh 2, Sindha Yuvraj 3, Mr. Nihal Vadher 4, 1 Electrical Engineering, Sigma Institute of Engineering, Vadodara 2 Electrical Engineering, Sigma Institute of Engineering, Vadodara 3 Electrical Engineering, Sigma Institute of Engineering, Vadodara 4 Asst. Proff. Electrical Engineering, Sigma Institute of Engineering, Vadodara Abstract - DC motors are used in various applications due to its speed, cost, low maintenance etc. It will be advantageous to develop a system, which uses RF communication to control the speed of dc motor without any wire communication.which executes with respect to signal sent by the RF transmitter. There are several application with dc motors in our daily life obviously there exists many applications where there might be a need to control the speed of dc motors. There exists many ways of controlling the speed of DC motor. Of the available ones, PWM technique is the most efficient one for controlling speed as well as energy saving. Keywords- speed and direction control; H-bridge; Dc motor; RF transmitter; RF receiver. I. INTRODUCTION DC motors are used in various applications in industries. It is always advantageous to control the speed and direction of motor in simplest manner. This paper represents controlling mechanism of speed and direction of a motor by using remote. In a separate remote RF modules are used in which STT-434 MHz is Transmitter, STR- 434 MHz is Receiver, HT12E RF is Encoder and HT12D is RF Decoder. Four switches are provided at the transmitter end, to control the speed and direction of the dc motor which is also connected at the receiver side. Two push-to-on switches are provided for increasing /decreasing the speed of the motor. Another Two push-toon switches are provided to rotate the motor in Clock wise / Counter clock wise direction. 16X2 LCD is connected at the receiver end to display the speed level of the motor and the direction. LED indication is also provided for visual indication. Figure1. Block Diagram of Power supply @IJAERD-2017, All rights Reserved 1
II. BLOCK DIAGRAM (TRANSMITTER) SW1 Antenna SW2 SW3 RF Encoder HT12E RF Transmitter SW4 Figure2. Block Diagram of RF transmitter. (a) Power supply:-this project uses regulated 5V, 500 ma & 12V, 500mA power supply. 7805 and 7812 three terminal voltage regulators are used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/12V step down transformer. (b) RF Encoder:-The four switches are interfaced to the RF transmitter through RF Encoder. The encoder continuously reads the status of switches; HT12E converts the parallel inputs into serial output. It encodes the 12 bit parallel data into serial for transmission through an RF transmitter. (c) RF Transmitter:-Transmitter, receiving serial data from encoder IC (HT12E), transmits it wirelessly to the RF receiver. (d) Wireless data transmission:-electrical communication transmitter and receiver techniques strive toward obtaining reliable communication at a low cost, with maximum utilization of the channel resources. The information transmitted by the transmitter is received by the destination via a physical medium called a receiver. This physical medium, which is wireless, introduces distortion, noise and interference in the transmitted information bearing signal. To counteract these effects is one of the requirements while designing a transmitter and receiver end technique. The other requirements are power and bandwidth efficiency at a low implementation complexity. (e) Switches:-Four On/Off switches are provided for controlling speed as well as direction. @IJAERD-2017, All rights Reserved 2
III. BLOCK DIAGRAM (RECEIVER) Antenna RF RECEIVER RF DECOD ER HT12D CRYSTAL OSCILLA TOR MCU 89S52 DISPLAY 16X2 H-BRIDGE L293D When an enable input is high, the associated drivers are enabled, and their outputs are active and in phase with their inputs. When the enable input is low, those drivers are disabled, and their outputs are off and in the high- POWER- ON RESET DC MOTOR Figure3. Block Diagram of RF receiver & Power supply (a) RF receiver:-the RF receiver receives serial data, and demodulates the transmitted data signal, and gives it to RF decoder. (b) RF decoder:-rf decoder converts the serial input into parallel outputs. It decodes the serial addresses and data received by, say, an RF receiver, into parallel data and sends them to output data pins. (c) Microcontroller unit:-at89s52 is a powerful microcontroller which provides a highly-flexible and costeffective solution to many embedded control applications. The AT89S52 provides the following standard feature: 8 KB of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and clock circuitry. (e) H-bridge:-The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5V to 36V. @IJAERD-2017, All rights Reserved 3
impedance state. With the proper data inputs, each pair of drivers forms a full H-bridge reversible drive suitable for motor applications. (f) Display:-16X2 LCD is connected at the receiver end to display the speed level of the motor and the direction. LED indication is also provided for visual indication. (g) DC motor:-dc motors are always preferred because of its speed, weight, size, and cost. You can control the speed of motor, direction of rotation; also do encoding of the rotation made by DC motor interfacing to the driven IC. In the current project the motion of rover is controlled by these DC motors of 100RPM and operates for 9V of DC voltage IV. H-BRIDGE CONFIGURATION Figure4. Circuit Diagram H-bridge S1 S2 S3 S4 RESULT 1 0 0 1 Forward 0 1 1 0 Reverse 0 0 0 0 Motor Free 0 1 0 1 Motor Brake 1 0 1 0 Motor Brake Table1. H-Bridge V. WORKING H-Bridge is used for the purpose of the direction control of dc motor. It is made up from four transistor switches. The four transistors are connected in bridge type manner that s why it is called as H-Bridge.S1, S2, S3, S4 are the four switches used, Out of this four switches two of them are switched on at same time which rotate motor in clockwise direction and another two switches can also be operated at same time for rotating motor in @IJAERD-2017, All rights Reserved 4
counter clockwise direction.when switch s1 and s4 are ON the motor moves in clockwise direction, when switch s2 and s3 are ON then motor moves anticlockwise direction. VI. PULSE WIDTH MODULATION Pulse Width Modulation PWM is an effective method for adjusting the amount of power delivered to the load. The microcontroller can generated PWM signal to adjusting the duty cycle of pulse simultaneously the motor terminal voltage can vary with duty cycle and also speed will be a vary. The ratio of on time to off time is called as duty cycle. The desired speed can be obtained by changing the duty cycle. The Pulse-Width- Modulation (PWM) in microcontroller is used to control duty cycle of DC motor drive.pwm is an entirely different approach to controlling the speed of a DC motor. Power is supplied to the motor in square wave of constant voltage but varying pulse-width or duty cycle. Duty cycle refers to the percentage of one cycle during which duty cycle of a continuous train of pulses. Since the frequency is held constant while the on-off time is varied, the duty cycle of PWM is determined by the pulse width. The figure shown below the change of duty cycle of the PWM microcontroller. The microcontroller having a 25% duty cycle then it provide a ¼ of power to the motor, when microcontroller having a 50% duty cycle then microcontroller provide a ½ of power to the motor, when microcontroller having a 75% duty cycle then microcontroller provide a ¾ of power to the motor and finally the microcontroller provide a 100% duty cycle then microcontroller provide a full power to the motor. Construction: Figure5. Pulse Width Modulation VII. DC MOTOR DC motors consist of one set of coils, called armature winding, inside another set of coils or a set of permanent magnets, called the stator. Applying a voltage to the coils produces a torque in the armature, resulting in motion. SPECIFICATIONS: 12 V DC Motor 1000 RPM 6 mm shaft diameter Motor diameter 28.5mm Load current = up to 9.5A(max) No load current = 800 ma(max) Figure5. DC motor. Stator @IJAERD-2017, All rights Reserved 5
The stator is the stationary part of a motor. The stator of a permanent magnet dc motor is composed of two or more permanent magnet pole pieces. The magnetic field can alternatively be created by an electromagnet. In this case, a DC coil (field winding) is wound around a magnetic material that forms part of the stator. Rotor The rotor is the inner part which rotates. The rotor is composed of windings (called armature windings) which are connected to the external circuit through a mechanical commutator.both stator and rotor are made of ferromagnetic materials. The two are separated by air-gap. Winding A winding is made up of series or parallel connection of coils. Armature winding - The winding through which the voltage is applied or induced. Field winding - The winding through which a current is passed to produce flux (for the electromagnet) Windings are usually made of copper. VIII. CIRCUIT DIAGRAM Figure6. circuit diagram. WORKING: The RF modules used here are STT-433 MHz transmitter,str-433 MHz receiver, HT12E RF encoder and HT12D RF decoder. Four switches are provided at the transmitter end, to control the speed and direction of dc motor @IJAERD-2017, All rights Reserved 6
which is connected at the receiver side. Two push to on switches are provided for increasing/decreasing the speed of motor. Two more push to on switches are provided to rotate the motor in clock wise/anti clock wise direction. The four switches are interfaced to the RF transmitter through RF encoder. The encoder continuously reads the status of switches, passes the data to the RF transmitter and the transmitter transmits the data. At the receiving end, the RF receiver receives this data and presents it to the microcontroller. Now, it is the job of the controller to read the data and perform the corresponding action i.e., to rotate the dc motor clockwise, anticlockwise, increase or decrease the speed of the data.16x2 LCD is connected at the receiver end to display the speed level of the motor and the direction. LED indication is also provided for visual indication.this project uses regulated 5V, 500 ma & 12V, 500mA power supply. 7805 and 7812 three terminal voltage regulators are used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/ 12V step down transformer. IX. HARDWARE IMPLEMNTATION List of Components Used For This Project 1. ENCODER 2. DECODER 3. MICROCONTROLLER 4. H BRIDGE 5. RF TRANSMITTER/RECEIVER 6. PUSH BUTTON SWITCHES 7. LCD DISPLAY 8. DC MOTOR 9. BATTERY 10. RESISTORS HARD WARE MOTOR CONTROL (RECEIVER) Figure7. hardware motor control model REMOTE CONTROL(TRANSMITTER) @IJAERD-2017, All rights Reserved 7
Figure8. Remote controller circuit X. CONCLUSION The speed and direction of a motor can be control by using remote in the range of 20 to 25 m which can be advantageous in some traction and industrial applications. By using PWM technique speed of motor can also be controlled which gives energy saving opportunity. Angular direction of motor rotation can also be controlled with the help of remote. XI. REFERENCES [1].A.K.Dewangan,NChakraborty,SShukla,VYadu, PWM Based Automatic Closed loop Speed Control Of DC Motor, International Journal of Engineering Trends and Technology, vol.3,pp.110-112. [2] Muhammad H. Rashid, Power Electronics Circuits Devices and Applications, Prentice Hall, publication New Delhi 2008, 3rd edition, pp.226-294. [3] Shruti Shrivastava, Jageshwar Rawat, Amit Agrawal, Controlling DC Motor Using Microcontroller(PIC16F72) With PWM, International Journal of Engineering Research, Volume No.1,Issue No. 2,pp.45-47. [4] Sandeep Kumar Singh, Harish Kumar, Kamal Singh, Amit Patel, A Survey And Study Of Different Types Of PWM Techniques Used In Induction Motor Drive International Journal of Engineering Science & Advanced Technology, Volume-4, Issue-1, 018-122 [5] I. MOAZZEM, S. RAHMAN, M A MATIN, Microcontroller based closed-loop automatic speed control of DC motor using PWM. [6] Jeetender Singh Chauhan, Dr. Rajesh Singh, Sunil Semwal, Shashank Mishra, PWM Based Speed Control of DC Geared Motor Using 802.15.4 LAN Standard Protocal, IJECT Vol. 3, Issue 4, Oct - Dec 2012. @IJAERD-2017, All rights Reserved 8