New Wireless Quick Charge!

Wireless electricity supply is a technology expected to be rapidly growing, and convenience, safety, economic efficiency, etc. are dramatically improved by wirelessly feeding electricity, such as electric power supply to EV cars, household electric appliances or IoT devices , We believe that new markets will expand as we have the potential to induce new dimension innovation in various industrial fields.

At our company, we developed technologies derived from energy-saving lighting inverter and developed AMR (improved magnetic resonance method) of original wireless power supply. This technology enables distance feed, position flexibility, high efficiency, high power compatible wireless power feed (non-contact). It can also be applied in a wide range of fields, it is low cost, less heat generation, safer, and can be adapted as upward compatibility of existing standards.


Issues of existing technology

Types and issues of wireless power transmission
Electromagnetic induction (MI) system: transmission efficiency is bad
It is around 55%, in particular, the heat generation of the power transmission coil is large
Reason: Power factor of primary coil is poor, reactive current is large, copper loss is large
Improve efficiency up to 75% for the moment
Improve to more than 90% when using resonance (However, ZVS condition is unstable)
Since it can not send large power, about 5 W is the limit (Qi standard)
Power can not be transmitted unless the coils are brought close to each other

Magnetic field resonance (MR) method Efficiency is good but robustness is low
Two resonance frequencies must be perfectly matched
The resonance frequency varies with the distance between the coils
It is still known only to a part in the academy yet
It is trying to forcely use an anti-resonance frequency that does not change the resonance frequency
The biggest disadvantage of the WiTricity method
A bimodal characteristic appears and an impedance matching unit becomes essential
When the inter-coil distance is determined to be constant, efficiency is high (90% or more)
It is vulnerable to inter-coil distance and position change (= low robustness)
Transmission power and efficiency deteriorate significantly when the distance relationship changes
If the distance between the coils is set to 40 cm, even if it is set to 30 cm or 50 cm, it is useless
No-load resonance coil voltage becomes too high and danger
Actual load fluctuates greatly
It is obvious on the equivalent circuit
Advantage of owned technology
We solved technical problems so far.

International patent application current resonance type AMR (Advanced MR)
⇒ Added super high-speed communication function on power supply side and power receiving side
⇒ always optimum power supply ⇒ high power and flexibility (robustness)
And high efficiency (80 to 90%) at the same time.
⇒ Soft switching with zero voltage switching (ZVS) operation reduces radiated noise.


Scope of application of new technology

Application range is small from small to large

Qi, PMA system performance improvement proposal possible
Proprietary charging method (electric power guide tool, toy etc.)
Research and development cooperation (underwater robot)
Medium-sized equipment (golf carts, senior cars, etc.)
In-plant equipment (AGV, forklift)
Rotating section feeding (slip ring, motor rotor)
Feeding in liquid
Internal medical device
Various power supply for aircraft, rockets, missiles and artificial satellites
EV Vehicle
Consumer electronics
Industrial drone


About the new method AMR

New method AMR
The Advanced Magnetic Resonance is an improved version of the MR system mainly based on the resonance on the secondary side

In the wireless power transmission device, a resonance circuit of a phase-locked coupling is formed on the secondary coil side, phase information (the resonance current flowing through the resonance circuit) is detected, and based on this phase information, the current of the drive current flowing through the primary coil The drive frequency is determined so that the phase is slightly delayed from the voltage phase and the primary coil is driven. Further, the decision value Q value determined by the leakage inductance of the secondary coil, the capacitance of the resonance capacitor, and the equivalent load resistance is set to be a certain value or more.

Eliminate resonance on the primary side
Primary coil is driven with high voltage
Frequency dependency on the primary side disappears and the equivalent circuit model becomes simple
Copper loss of the primary coil decreases and heat generation decreases
Only the secondary side has frequency dependence
Advantage of the new method AMR

Resistant to change in distance and position between power transmission side and power receiving side
Low cost
It can respond widely from medium to small power to large power
Can correspond as upward compatibility of Qi (electromagnetic induction)
The circuit is simple (advanced analog technology)
High transmission efficiency and less heat generation


About us

Company name :  WQC Co., Ltd.
Location :  2-28-1,Kamishakujii,Nerima-ku, Tokyo 177-0044 Japan
Phone number : +81-3-3326-9222
Fax number : +81-20-4668-7041
President & CEO: Masakazu Ushijima
Establishment : December 17, 2015
Capital : 16.7 million yen
Development branch : 1-19-15 Ebisu, Shibuya-ku, Tokyo 150-0013 Inside GH of Unosawa Tokyu Building 5th floor
Business description : Wireless power transmission related technology consulting Contract development of wireless power transmission related technology(development / design)
Wireless power transfer technology (AMR) Patent license grant
Bank : Bank of Tokyo-Mitsubishi UFJ Takada Baba branch
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