Tagged Questions
4
votes
1answer
73 views
2 full bridge with 2 secondary winding in series… is it possible?
simulate this circuit – Schematic created using CircuitLab
Is this possible? Think of the center tap transformer as a 2 winding connected in series
5
votes
3answers
213 views
Anyone know the purpose of these two inductors around a metallic ring?
So this link on ebay shows a power board that I have taken out from my microwave.
What is the purpose of these two wrapped around a metal ring? Also in general what is the purpose of this power board ...
1
vote
1answer
70 views
transformer conservation of power
lets say we have a transformer, on the left side, it is 220 v and on the right side, it is 10 v. we know that power is conserved meaning power on left is equal to right (ignoring loss). I understand ...
4
votes
1answer
242 views
Transfer power effectively from one coil to another through air
I want to build my own wooden alarm clock.
I want the surface to be smooth without any connectors anywhere. My idea is to place one coil beneath the alarm clock, and another pickup coil inside. I ...
0
votes
1answer
208 views
Effect of decreasing input voltage of transformer on output voltage
I have designed a device which is controlled with a PIC micro controller.This micro's power is +5 volt. I have used a transformer for converting +220 volt to lower voltage +15 volt. Then a 7805 ...
4
votes
1answer
268 views
Is it possible to have a device with metal case and wireless charging?
Recently I encountered the following idea: that a mobile device manufacturer is not interested in including wireless charging in his devices because that prohibits him from using metal cases in the ...
3
votes
1answer
279 views
Dual primary / dual secondary transformer heat up
I've built this 220v DC motor controller. I use a 2x110v - 2x15v transformer to power up the stator.
The transformer is a Myrra 45064 with the primary windings connected as follows: pins 1 and 9 ...
5
votes
2answers
579 views
Why do thunderstorms knock out power?
It isn't like lightning strikes the wires. And surely the whole apparatus is designed to be water-proof. So what is it that causes power outages during thunderstorms?
3
votes
1answer
147 views
Why does a transformer for halogen bulbs blow when bulbs are too strong?
If I have a transformer for 4x20W but I use halogen bulbs let's say 4x60W, why does the transformer blow then? I always thought that the bulbs are only as strong as the transformer gives, but it's the ...
5
votes
3answers
1k views
How does a three-phase transformer work with phases sharing a common core?
Google search reveals a lot of pictures of three-phase transformers. Looks like a common setup is to have three pairs of winding and a shared core. The core typically consists of three "bars" in ...
1
vote
2answers
1k views
What causes unequal phase-to-neutral voltages in three-phase distribution systems?
A four-wires cable runs into an apartment building to supply it with three-phase 380/220V alternating current. Each apartment is connected to one phase, different apartments are connected to different ...
2
votes
2answers
727 views
Is there any difference between “induction” and “resonant” wireless energy transfer?
This article compares two systems for wireless energy transfer - one is by WiTricity and another is Bombardier PRIMOVE. I've read their descriptions thoroughly - to me they both look like resonant ...
6
votes
4answers
557 views
How is inductive wireless charging of a moving vehicle on a public road possible in efficient way?
Looks like one of the major problems of wireless energy transfer is efficiency. For example, Magne Charge high power charging system seems to have about 86% efficiency which means that quite a lot of ...
3
votes
1answer
330 views
What's the need for higher frequency in inductive charging systems?
Consider an inductive charging system like Magne Charge - it has a rather huge "coupler" coil off the vehicle and a corresponding slot on the vehicle and the coils in the "coupler" and in the slot are ...
7
votes
1answer
278 views
Why does short distance wireless energy transfer have such low efficiency?
Wikipedia and numerous other sources cite the following statement about Magne Charge high-power inductive charging system:
For example, the Magne Charge system employed high-frequency induction to ...
6
votes
4answers
670 views
How does a wireless charger work without a magnetic core passing through both “coils”?
Every time I hear the description of a wireless charging system it goes like this: "remember a transformer? It's the same here - one coil is in the base and another is in the device and when you put ...
3
votes
4answers
371 views
Why don't we have wireless charger in every portable device yet?
Today I found Texas Instruments announced a circuit for wireless charging - all the materials emphasis how tiny, lightweight, portable, efficient and otherwise cool it is.
While I of course like the ...
3
votes
1answer
770 views
Can single clamp measure total current from 3 wires?
Single AC clamp can measure current flowing through a single wire in a non-invasive way. There are AVR/Arduino projects use such a clamp to measure house power usage. However, they use 3 clamps for 3 ...
