A small electric vehicle is powered by a 96.1 V battery and uses a series wound motor. It has a step-down chopper for forward drive and a step-up chopper for regenerative braking. The total armature resistance is O.1 Q, and the armature voltage constant is 10 mV/A-rad/s. Descending a hill in regeneration mode the motor speed is 750 rev/min and the armature current is a constant average value of 80 A. Calculate the value of the duty cycle required and the .available braking power

A small electric vehicle is powered by a 96.1 V battery and uses a series wound motor. It has a step-down chopper for forward drive and a step-up chopper for regenerative braking. The total armature resistance is O.1 Q, and the armature voltage constant is 10 mV/A-rad/s. Descending a hill in regeneration mode the motor speed is 750 rev/min and the armature current is a constant average value of 80 A. Calculate the value of the duty cycle required and the .available braking power

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

See similar textbooks

Similar questions

A 400 kW, three-blade wind turbine is designed to deliver power at a wind speed of 15 m/s. The blades have a depth of 14 m, and the rated speed of the turbine is 48 rpm. The air density is 1.226 kg/m3. Calculate (a) area swept out by the turbine (b) wind power available to drive the turbine (c) capacity factor of the turbine
Q 03: Briefly discuss, how the energy consumptions for operations of a fork lifter could be justified. Suppose that a fork lifter has a total energy consumption of 150 W.Hr. The total trips of the vehicle are 375. How the battery duty cycle may be calculated in this case?
Whale and Kanmuro are two islands located at the Chimera archipelago. These two are separated by a distance of 16 miles. A power link is to be established between them. The power link delivers a maximum power of 584 megawatts at full capacity with an operating voltage of 580 kilovolts. Note that 1 mile is 1.6 kilometers. Solve for the resistivity (in ohm-micrometers) of the cable asusming a conductor diameter of 1.55 centimeters.
Your company is considering the installation of a 2 MW wind turbine with a rotor diameter of 90 m in a location with average wind v = 8.5 m/s. The turbine has a cut-in velocity of 5 m/s and a cut-out velocity of 25 m/s. The capacity factor is 0.45. The installed cost of the turbine is $3,500,000. Operating expenses are $225,000 per year. The system has a power coefficient (electric power generated divided by wind power) of 0.45. What price would you have to get for the electricity you produce to obtain a 10% return on the plant investment assuming a project lifetime of 20 years? Use the tables for the cumulative wind power distribution in the notes on wind probability to answer this question. Assume an air density of 1.225 kg/m3.
An electricity power plant delivers energy at a rate of 20 MW to a city 1 km away. The common voltage output of commercial electricity generator is 22 kV. In order to reduce the power loss during transmission, a step-up transformer is used to boost the voltage to 230 kV before transmission. If the resistance of the transmission wires is 2 Ω and the electricity cost is about HK$1 per kWh, estimate the cost of electricity loss due to “joule heating” in the wires in one day.
A 250V, 950 RPM, 175 A separately excited motor with Ra=0.06 Ohm. The motor is fed from a chopper which provides both motoring and braking operations. The source dc voltage is 280V. If maximum duty ratio of chopper is limited to 0.93 and maximum permissible motor current is twice the rated, calculate maximum permissible motor speed obtainable without field weakening and power fed to the source.
Q 1 You are hired as Maintenance Engineer for Pakistan Accumulator Ltd., the company that manufacture branded batteries such as Volta and Osaka. The battery manufacturing factory is a process industry and consists of several plants. One of these plants is Grid Casting. Grids are used in batteries for manufacturing of plates including positive & negative. Different types of grids produced for different type of batteries having different thickness & weight for different battery. For casting of these grids, 03 % Sb alloy is used. 24 grid casting machines are operational in workshop. Inside Casing Machine, alloy lead melted at 400°? in furnace and alloy is injected in molds of grids, resulting formation of grid in hard form. After set time grids are dropped in tray and extra parts are removed. To melt alloy lead to 400℃, furnace is controlled by a closed electronic system. The system consists of ignition, temperature sensor, temperature adjuster, and gas valve. The single-wire…
A 500V, single-phase SM gives a net output mechanical power of 7.46 kW and operates at 0.9 pf lag. The effective resistance is 0.8Ω If the iron loss and friction losses are 500W and excitation losses are 800W, calculate a. the armature current b. efficiency
a) If the cost of electricity consumption in Oman is OR 0.020/unit (where, 1 unit = 1 kWH), Calculate the monthly electricity bill for a load usage of 11 lamps (5 watts each), 11 fans (89 watts each) and 1 TV (341 watts) for 8hrs a day. (b) Calculate the efficiency of a solar PV module whose length is 159 cm and width is 105 cm and produces a 256 W maximum power when exposed to 920 W/m2 solar irradiance?
4) The coil of a moving-coil loudspeaker has a mean diameter of 30 mm and is wound with 800 turns. It is situated in a radial magnetic field of 0.5 T. Calculate the force on the coil, in newtons, when the current is 12 mA.
A meeting hall in an organization is to be provided with a lighting installation. The hall is 30 m × 20 m × 8 m (high). The mounting height is 5 m and the required level of illumination is 144 lm/m2. Design a lighting system for the hall with the given data. Lumens/watt for 200-W lamp = 12 and Lumens/ watt for 500-W lamp = 16. Utilization coefficient = 0.6 Maintenance factor = 0.75 space/height ratio=1 Using metal filament lamps, estimate the following: Flux Luman output per 200 W lamp Luman output per 500 W lamp Number of 500W lamps required Number of 220W lamps required Draw the spacing layout of these lamps State the reason if any of these 2 lamps cannot be arranged in the hall with the given specification. What is the significance of ‘room surface maintenance factor’ and ‘utilization factor’ in the lighting design
The equation of characteristics of the system is as follows. 1. Determine the stability of this system, and write the reason. 2. Write the number of poles this system has in the right quadrant and the reason.