A schematic arrangement for a two quadrant controller is shown on figure below. This figure show us the outer speed control loop and the inner current control loop. The tachogenerator derive the speed feedback signal, although alternatively an approximation to the motor speed can be derived by feeding back a signal proportional to the motor voltag
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e, (AVF). For servo applications, position feedback can be included by using a position encoder on the motor shaft. The tacho- output voltage is compared with a speed reference signal by the feed feedback loop. The current reference command is given by the voltage error signal. In the inner control loop, the current command signal is compared with the actual motor current. A current limit setting which protects the motor and the devices from overcurrents is included in this control loop. The current demand is maintained below the maximum level by this current limit setting if the controller demands a large speed change. Motoring or regenerating operation is detected directly from the polarity of the voltage error signal. This will be used to determine whether it is the top or bottom MOSFET which is controlling the current. To ensure that control does not oscillate between the motoring and regenerating modest low motor currents, the motoring/regenerating logic circuit includes some hysteresis. By controlling the switching sequences to the main PowerMOS devices, there are several possible ways of controlling motor current. The motor current is compared with the reference signal and allowed current ripple tolerance in tolerance band control. If the actual current is greater than the allowed maximum value of the tolerance band during motoring operation, then the output comparator turns off the gate drive to the power MOSFET...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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