Magnetic levitation devices are mainly divided into two kinds: Power drive, Powerless drive
Power drive is divided into up-suction magnetic levitation and down-push magnetic levitation
This article mainly introduces the up-suction magnetic levitation
- Up-suction type magnetic levitation
This magnetic levitation has several advantages:
1. the levitation is more stable, you can hardly see any jitter in the levitation, thanks to the more sophisticated control algorithm.
2. Almost zero noise, because the Arduino’s PWM frequency is 490Hz, which is within the hearing range of the human ear, so you can hear the ear-piercing sound when the previous device works, and this time the PWM frequency is increased to 20kHz, and the control algorithm is interpolated and filtered, so the noise is almost eliminated.
3 . Power consumption has been greatly controlled, and the whole device is exceptionally power-saving, yes you heard right, magnetic levitation is very power-saving, or because of the improved control algorithm, using a number of closed-loop control, including a current loop, which means that the algorithm will adjust the levitation to a suitable position, and this position of the magnetic force (excluding the force of the coil) is perfectly balanced with gravity so that the magnetic force offset almost The coil only needs to be near this balance point, the extremely slight adjustment, so the current is very small, the actual measurement of standby current 30mA, plus the float work current 50mA, that is, the coil consumption of current only about 20mA, even with the power consumption of a microcontroller.
4. the weight of suspended objects greatly increased, this device can be suspended a maximum of how many suspended objects? Large to exaggerate, about 2kg is no problem, this is due to the above point, the current ring support, no matter how heavy the suspension, its gravity will be balanced with the magnetic force, only the heavier the floating suspension, the final balance of the location is closer to the core of the coil. More interestingly, regardless of the weight of the suspended object, the final power consumption is not changed, which is about 50mA. Because the magnetic force required near the balance point of the coil is very small.
5. This is also a very interesting point. The device can realize the power failure suspension automatically on the suction. In practice, when the power is off, the levitation may damage the items on the base if they fall, so it is necessary to achieve automatic suction of the power failure. But, as a matter of fact, when the power is off, the microcontroller is not working. So how can it still control the suspension? If not, as the levitation is stable near the equilibrium point, then the power failure on the suction or fall is completely random. How to ensure that 100% is on the suction? The answer is, do not let it work near the balance point. Let it work a little above the balance point, so that, in fact, the coil is not provided by the suction force, but repulsion to make the suspension balance, so once the power fails, the repulsion disappeared, and the suspension on its own suction it. This is why the standby current is 30ma, while the working current is 50ma, of which 20ma is used to provide repulsive force to the coil. In fact, if this function is not required, the power consumption of the coil can be reduced to almost 0!
6. And the core point is that all parameters are self-tuning, so they can adapt to the weight of the suspended object.
