Week 9 : Wireless mobile charger in market

Objectives:

1. To make research more on the devices that already had been on market
2. To study the construct of the wireless mobile charger 

Methods:

1. Bought (online) the wireless mobile charger that already on market 
2. Test if the wireless charger would function with mobile phone
3. Open the wireless charger to observe its parts

Results:

 

Figure 1: Wireless QI charger

 

 Figure 2: The wireless charger been plugged on to USB laptop

 

Figure 3: Phone being charged as soon as the charger being plugged

 

Figure 4: The construction of the wireless charger receiver

 

Figure 5: The construction of the wireless charger transmitter

 

Figure 6: The wireless charger transmitter circuit

Conclusion:

For this week, I have decided to bought my own wireless mobile charger online. The product is originality from China. It cost me about RM60 for this device. As we can see, the construction of the wireless mobile charger is quite simple. The circuit is quite small. It is made to fit into its body which is also quite small. It's just as big as a man's palm. As for the receiver and the transmitter, it is made of a coil. Its using a concept as a transformer which has been discussed in my previous blog. Meanwhile, the transmitter circuit is quite complicated. It is because the circuit has to be small to be fitted to its body. All its components is integrated into one small circuit. This week, my progress is on the observation of the wireless charger construction which has been on market is achieved as I already dismantle or disassemble all the wireless charger that I have bought. Only the physical construction that already been observed. The circuit is quite complicated but will be studied by me later.

Week 8 : Another comparison of wireless power transfer

Objectives:

1. To get the idea by making comparison of others project
2. To determine whether the size of the transmitter coil would affect the range of wireless power transfer

Methods:

1. By making some research on internet
2. By comparing others project on wireless power transfer
3. Attachment below shows on the project

Results: 
 

Figure 1: Wireless power transfer powered up a small bulb

Figure 2: Circuit diagram for the wireless power transfer transmitter 

Figure 3: Video showing on the commissioning of the wireless power transfer 

Conclusion:

As for conclusion, I found that with increase the size or diameter of the coil, the range of the wireless power transfer also increase. Also, with the increment of the coil loop, will make the range increase. This is because, by increasing these two factors, the resonant frequency for receiver and transmitter also will be decrease, but to achieve this, both of the circuit should resonate at the same frequency which means that the loop should on the same size. Larger loop with the same capacitance value will  lower the resonant frequency. The best way to increase the range is by lowering the resonant frequency. There are also another way to increase the range of the wireless power transfer such as by inserting ferrite core into a loop which will decrease the resonant frequency. The research on this factor to increase the range of the wireless power transfer still in progress.