EveryCircuit
Powering up...
Circuit
Public
Private
Unlisted
Save

catch diodes H Bridge Actuator with Back EMF

@clementereyes
9 years ago
https://everycircuit.com/circuit/4576146245287936
V¬=L(di/dt) V¬ is back EMF. delta Current is inversley proportonal to delta time, times Inductance. This circuit is set driven for analog sine wave at 1Hz. This will give a smooth transition for the actuator. Motor serves as gears. the lesser resistance (load %) the higher BEMF. Also, the faster the time (EM time constant), the less BEMF. Inductive coils serve as motor coils for brushless platform. A H-Bridge for use as a motor driver switches direction by comparing an input voltage on a signal line to a reference voltage generated by a voltage divider. Importantly, there is neglible current draw from the signal line. The voltage divider resistors can be varied to match the input signal line voltage thresholds. This modern variant uses mosfets in the h-bridge but older variants use transistors that have an undesirable characteristic of generating alot of heat for comparatively little current transfer. Using transistors instead of mosfets would also require the introduction of diodes to clamp the back EMF and protect the transistors (mosfets usually have clamping diodes built in). In practice an enable signal can be provided by controlling the supply voltage (typically the ground) to a dual comparator chip that would house the pair of comparitors.
Comments
Post