To find the power of an internal combustion engine (ICE) of a car, install it on a special stand that will give its maximum power. If this is not possible, you can calculate the engine power by measuring its acceleration dynamics to 100 km / h, having previously recognized its mass in the technical passport. Determine the power of the electric motor by its dimensions or measure the voltage and current on its windings, and then make a calculation.
It is necessary
stopwatch, tester, caliper
Instructions
Step 1
Calculating the power of a car's internal combustion engine As a rule, the maximum power of a car engine is indicated in the technical documentation, but over time, when the engine's resource is depleted, its power decreases. To find it, drive the car to a special stand, where experts measure the engine power at the moment.
Step 2
If this is not possible, find out the mass of the car from the data sheet, calculate the mass of the fuel and the driver poured into it, and then accelerate the car as quickly as possible to 100 km / h, fixing the acceleration time in seconds.
Step 3
To calculate the power, the total weight of the vehicle, driver and fuel, multiply by 27.78 (this is the speed of 100 km / h converted to meters per second) squared and divide by twice the acceleration time P = 27.78² * m / (2 * t). Get the power value in watts. To convert it to kilowatts, multiply by 1000. To convert the value to horsepower, divide the power in kilowatts by 0.735.
Step 4
Calculating Motor Power Connect the motor to a known voltage source. Measure the current on each of its windings with a tester. Measure in amperes. Find the sum of the currents in all windings. Multiply the obtained value by the voltage of the current source: P = UI. This will be the power consumption of the electric motor.
Step 5
To determine the power of a motor by its dimensions, measure the diameter of the stator core and its length. Measure in centimeters - with a tape measure and a caliper. Determine the synchronous speed of the shaft and the network where the motor is connected.
Step 6
Determine the pole division constant. Multiply the diameter by the synchronous frequency and 3, 14 and divide the result by the product of the mains frequency and 120 (3, 14 * D * n / (120 * f)). From the pole division and the number of poles, determine the constant C for a given motor using the table. Calculate its power by multiplying the constant, the square of the shaft diameter, the body length, the synchronous speed and the number 10 ^ (- 6): P = C * D² * l * n * 10 ^ (- 6). The calculation will be done in kilowatts.
