The LabVolt Motors, Generators and Controls - Lab Report Example

The LabVolt Motors, Generators and Controls” Insert Name Insert Name of University Insert Name of Course Insert Name of Professor April 10, 2014 Table of Contents DC motor speed control: 1 Unit 5 – The Stepper Motor and Controller 8 DC motor speed control: Introduction In a DC motor there is housing, bearings, a stator, shaft and rotor, rotor is Armature and rotates in inside stator while stator has field windings that carrying magnetic field. This paper intends to carry out analogue speed control of a DC motor and pulsed speed control of a DC motor. This will be done using the LabVolt software interface, along with the F.A.C.E.T. circuit board, the operation of a DC motor and its speed control are to be investigated. The relationship between armature current and torque, along with the interaction between armature voltage and RPM were to be demonstrated and observed. A comparison was then to be made between open-loop and closed-loop linear speed control circuits. To test pulsed speed control of DC motor similar equipment will be used except that a pulse mode closed-loop control circuit will be used. THEORY: The speed of DC shunt motor is calculated using involves the applied voltage, the current in armature, the armature resistance, and field flux, constant for a give motor. The following formulae is applied N= K where V= applied voltage, I = current in armature, K= constant for a motor, R= armature circuit resistance in ohm, = Flux K= where Z= number of conductors, P= number of poles of the motor and A = Number of parallel paths In our case the armature and field windings will connected parallel each other. Current in armature IS always different with the current of the field. The current in the armature depends on the loading while it is not the same with current from the field. The armature current is produced by field of the armature conductors and has the ability to influence the field strength while shunt field flux remains constant. Experimental Setup & Procedure To begin with the following equipment were assembled Equipment Specification DC Shunt motor 5-HP, 1500 rpm, 16.7 amp, 220 V Pulse amplifier Tachometer (0-10000) r. p. m. Voltmeter (0-300) volts Ammeter (0-1/2) A(0-5/10) A Rehostat 260Ω, 1.2 A Rehostat (0-2000) rpm Table 1: table of equipments Analogue speed control of a DC motor: we begin by connecting the circuit shown below; Figure 1: circuit for Analogue DC motor speed control After connecting the motor is started at a three pointer. It is run different speeds and values of resistance and their reading recorded in the table. The reading is obtained from voltmeter, tachometer and ammeter. Then calculation of power output, torque, and efficiency is made. Lastly graphs are of torque vs. efficiency and speed vs. armature voltage drawn. OBSERVATION TABLE: Sl. No Observation             Motor speed Generation output LOSS Motor output Motor input Efficiency   voltage Current speed Voltage (Vg) Current (Ig ) Vg X Ig IgR 6+7 Vm X Im Output Input   Volts Amps r.p.m Volts Amps watts watts watts watts %   1 2 3 4 5 6 7 8 9 10   2 0.5 1000 1.8 0.35 0.63 0.0875 0.7175 1 72%   4 0.7 750 3.6 0.55 1.98 0.1375 2.1175 2.8 76%   8 0.75 600 7.2 0.64 4.608 0.16 4.768 6 79%   10 0.85 550 9 0.78 7.02 0.195 7.215 8.5 85%   15 0.93 600 13.6 0.84 11.424 0.21 11.634 13.95 83%                       R= 0.25 Pulsed speed control of a DC motor In this case an amplifier was used to reduce distortion of power production and this case a Pulse amplifier is connected to circuit. The result is recorded as shown below Load % I V CF of I DF DPF Power factor RF 10 1.8 5 1.72 0.99 0.896 0.995 0.005 30 1.72 5.45 1.73 0.99 0.892 0.993 0.007 50 1.52 6.2 1.72 0.99 0.89 0.99 0.01 70 1.45 6.5 1.73 0.99 0.889 0.985 0.015 90 1.26 6.9 1.72 0.99 0.885 0.98 0.02 100 1.15 7.15 1.73 0.99 0.88 0.975 0.025 Table 2: 10-pulse results Load % I V CF of I DF DPF Power factor RF 10 1.6 6 1.72 0.99 0.896 0.99 0.01 30 1.56 6.5 1.73 0.99 0.892 0.99 0.01 50 1.52 6.9 1.72 0.99 0.89 0.99 0.01 70 1.48 7.2 1.73 0.99 0.889 0.99 0.01 90 1.27 7.5 1.72 0.99 0.885 0.99 0.01 100 1.2 7.8 1.73 0.99 0.88 0.98 0.02 Table 3: 30-pulse results Results & Discussion A graph of speed vs. Motor output has been plotted as shown below and from the graph it can be noted that loading continues speed of the reduces. This means that speed of the motor is proportional to the motor output. This also depends on the loss and output of power. From the results can also be noted that efficiency increases with increase in output. At high speed, the voltage reduces as the mass flow is reduced. Pulsed speed control of a DC motor Discussion Open-loop control uses fixed voltage to set the motor speed for specific torque load The voltage needed to turn the load is in rpm/KS TACH Discussion of Results There is power lost when using pulse amplifiers and larger large pulse losses more power from the system. However they have the ability to maintain stable drive the motor better to compensate for the lost. The power generated by the motor was determined as = VI while power lost .power lost is = V-VLost Conclusion The curves from the experiment indicate that when the motor current increases with the load and the speed decreases slightly with the load then reaches the maximum of 80% to 90% before beginning to fall. From the pulse speed control of a DC motor, a 30-pulse speed control showed the stable results in terms of power factor as loading increased. Unit 5 – The Stepper Motor and Controller Introduction The experiment was set using stepper motor, F.A.C.E.T base unit, Motors and generators on the board and Multimeter to show how it helps to drive a motor. A total of two experiments were designed from this experimental setup, each of these had a different objective under investigation from the others, and all the parameters that were investigated were compared with time interval upon which several values changed. This paper reports on the findings obtained from these setting. Before commencing data retrieval the system was connected to a preferred personal computer with ideal software that could actually retrieve the data. Power cables were connected to the main supply. As mentioned two experiments of stepper motor and the stepper motor controller were used, in experiment, a form of closed loop control where power was switched on when the power below a certain limit, and was switched off when it went above a certain level to ensure it went back to a given range. An overlap that would have alternated this power between these desired ranges was therefore worth investigating. The second setup in this experiment investigated the controller output, these involved; a reverse action involving the output decline that was looked at with an increase in voltage. Theory The stepper motor is an electromagnetic actuator which is used to drive the motor through digital pulse. However this rotates a motor a certain degrees, therefore more digital pulses will lead to a rotation. Stepper motor is computer generated and responds to commands made to make the motor rotate. The control circuit was designed as shown in figure below for the controller. when the controller is is switched on the motor rotates making cycles and results is recorded below Figure 2: the Stepper-Motor Controller. , The results obtained from the experiment were as shown below; State Q1 Q0 1A 2A 3A 4A HOME A 0 0 1 0 1 0 1 B 0 1 1 0 0 1 0 C 1 0 0 1 0 1 0 D 1 1 0 1 1 0 0 Based on table 3.1, the output equations 3.2-3.6 were created. Experimental Setup & Procedure Equipment required for the experiment were F.A.C.E.T base unit, Motors and generators on the board and Multimeter . The set up uses The Stepper Motor and Controller process controller, which uses a self contained process of simulation with an inbuilt controller function, h was connected to power source on the F.A.C.E.T base unit, while motor received a digital signal that was to convert drive the motor. A stepper additional circuit was meant to modify the received signals. . In this experimental set up, the method that was utilised involved altering parameters under investigations and measuring their corresponding effects on the temperature changes, these were then compared with the set values so at to generate a control signal that could enable regulation of the electrical power supply to motor. Results & Discussion When the circuit was made running began using all the switches that were available. The combinations of the inputs switches, when used to make it drive the motor. The motor did not turn during the first trial so the high speed logic indicator was used to troubleshoot the circuit. Conclusion The use of logic gates and circuits in designing a stepper-motor controller. A state transition diagram and truth tables were created to describe the desired operation of the circuit. Boolean equations were derived from the truth tables and a schematic diagram was created. The circuit was built based on the diagram and testing verified its proper function. References Giambattista, A. ( 2009). Student Solutions Manual to accompany Physics. New York: McGraw-Hill Giambattista, A., Richardson, B. M & Richardson, R.C. (2009). College physics. New York: McGraw-Hill. Lon Turnbull, L. & David Wagoner, D. (2004). Physics 2111 Laboratory Manual Wilson, J., (1994). Physics Laboratory Experiments. New York: Houghton Mifflin Company Serway R & Jewett, J., 2008. Physics for Scientists and Engineers /With Modern Physics. New York: Thomson Read More

Pulsed speed control of a DC motor Discussion Open-loop control uses fixed voltage to set the motor speed for specific torque load The voltage needed to turn the load is in rpm/KS TACH Discussion of Results There is power lost when using pulse amplifiers and larger large pulse losses more power from the system. However they have the ability to maintain stable drive the motor better to compensate for the lost. The power generated by the motor was determined as = VI while power lost .power lost is = V-VLost Conclusion The curves from the experiment indicate that when the motor current increases with the load and the speed decreases slightly with the load then reaches the maximum of 80% to 90% before beginning to fall.

From the pulse speed control of a DC motor, a 30-pulse speed control showed the stable results in terms of power factor as loading increased. Unit 5 – The Stepper Motor and Controller Introduction The experiment was set using stepper motor, F.A.C.E.T base unit, Motors and generators on the board and Multimeter to show how it helps to drive a motor. A total of two experiments were designed from this experimental setup, each of these had a different objective under investigation from the others, and all the parameters that were investigated were compared with time interval upon which several values changed.

This paper reports on the findings obtained from these setting. Before commencing data retrieval the system was connected to a preferred personal computer with ideal software that could actually retrieve the data. Power cables were connected to the main supply. As mentioned two experiments of stepper motor and the stepper motor controller were used, in experiment, a form of closed loop control where power was switched on when the power below a certain limit, and was switched off when it went above a certain level to ensure it went back to a given range.

An overlap that would have alternated this power between these desired ranges was therefore worth investigating. The second setup in this experiment investigated the controller output, these involved; a reverse action involving the output decline that was looked at with an increase in voltage. Theory The stepper motor is an electromagnetic actuator which is used to drive the motor through digital pulse. However this rotates a motor a certain degrees, therefore more digital pulses will lead to a rotation.

Stepper motor is computer generated and responds to commands made to make the motor rotate. The control circuit was designed as shown in figure below for the controller. when the controller is is switched on the motor rotates making cycles and results is recorded below Figure 2: the Stepper-Motor Controller. , The results obtained from the experiment were as shown below; State Q1 Q0 1A 2A 3A 4A HOME A 0 0 1 0 1 0 1 B 0 1 1 0 0 1 0 C 1 0 0 1 0 1 0 D 1 1 0 1 1 0 0 Based on table 3.

1, the output equations 3.2-3.6 were created. Experimental Setup & Procedure Equipment required for the experiment were F.A.C.E.T base unit, Motors and generators on the board and Multimeter . The set up uses The Stepper Motor and Controller process controller, which uses a self contained process of simulation with an inbuilt controller function, h was connected to power source on the F.A.C.E.T base unit, while motor received a digital signal that was to convert drive the motor.

A stepper additional circuit was meant to modify the received signals. . In this experimental set up, the method that was utilised involved altering parameters under investigations and measuring their corresponding effects on the temperature changes, these were then compared with the set values so at to generate a control signal that could enable regulation of the electrical power supply to motor. Results & Discussion When the circuit was made running began using all the switches that were available.

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