What is back EMF and its significance in DC machines?
5.7. A DC machine has a back-emf constant of 0.24 V/(rad/s) and a resistance of 0.5 ohms. It is operating from a 12V DC power supply. At its rated speed of 400 rpm, calculate its (a) rated back-emf voltage (that is, the back-emf at rated speed) (b)rated current (that is, the current at rated speed) (c) rated torque (d) rated output power POUT= To (e) rated output power POUT = EI (f) rated input power (g) rated efficiency-PouTlPi (h) rated...
Q1b) DC Machines [ 6 marks ] You are given a 24 V DC motor. When you connect it to a 24 V supply, under no-load conditions it spins at 2,000 rpm. With the same 24 V supply, when the motor is stalled, the input current is 50 A. i) Calculate the back-emf constant and hence the stall torque of the motor. Find also the armature resistance. [3 marks ] ii) The DC motor has a rated input current of...
A certain dc motor has R,-1.5Ω, 1,-10A, and produces a back emf EA-300V. while operating at a speed of 1500rpm. Determine the voltage applied to the armature, the developed torque, and the developed power 104 e ge applied to the an
Question 3: DC motors can be simplistically modeled as shown in Figure 5 MoTor back emf Vi: +1 Resistor Ra Ia Figure 5: Simplified model of DC Motor (a) Write the three characteristic equations that determine the behavior of the DC motor. Denote torque constant and speed constant as Ka, K, respectively. (b) Motor parameters are the quantities that define the behavior of the motor. List the motor parameters from the described model. What are their units? (c) For given...
3. The figure shows a DC servomotor system. Assume that the armature inductance of the DC motor is negligible (it is not shown in the figure.) Obtain the transfer function between the output 02 and the input ea. (Hint: the motor torque T-Kia, and its back emf, es kvm) Gear 1 y constant Gear 2
How does self-inductance create back emf?
A motor operating on 230 V electricity has a 188 V back emf at operating speed and draws a 12.8 A current. (a) What is its resistance (in ?)? 4 (b) What current (in A) does it draw when it is first started?
The armature windings of a dc motor have a resistance of 8.0 Ω . The motor is connected to a 120-V line, and when the motor reaches full speed against its normal load, the back emf is 108 V. The load is increased so it causes the motor to run at half speed. What will be the current in the motor in this case? (Express your answer to two significant figures and include the appropriate units.)
Problem 29.41 Constants I Periodic Table Part A The back emf in a motor is 64 V when operating at 1300 rpm What would be the back emf at 2600 rpm if the magnetic field is unchanged? Express your answer using two significant fgiures. VAD ? V Submit Request Answer Provide Feedback
1. For example, the generator can produces a DC EMF (constant sign voltage). Explain how this differs from the generator in the simulation. 2. What changes can you make in the simulation to maximize the voltage produced? 3. Describe the similarities and differences between a generator and a motor