Systems and methods for dynamic wireless power transfer
View Patent ↗Systems and methods for dynamic wireless power transfer (DWPT) are provided (e.g., DWPT of electric vehicles (EVs)). The inductor of the secondary compensation network can be integrated with the main inductive coil, which can introduce mutual couplings (e.g., three mutual couplings) in the system. The additional mutual coupling leads to a smooth power profile and an increase in power (e.g., power transferred during dynamic charging). The secondary compensation network inductor coil and the secondary main coil can be designed, configured, and/or arranged in a way that mutual coupling between them and the transmitter coils produces a uniform power profile.
1. A system for dynamic wireless power transfer (DWPT), the system comprising:
a transmitter side configured to wirelessly transmit power to a receiver coil during DWPT, the transmitter side comprising a plurality of transmitter coils; and
a receiver side configured to wirelessly receive power from the transmitter side during DWPT, the receiver side comprising the receiver coil,
the receiver side further comprising a secondary compensation network comprising a compensation inductor integrated with the receiver coil and disposed in parallel with the receiver coil,
the compensation inductor having a same outer length as the receiver coil and a same inner length as the receiver coil,
the system being configured to produce an output voltage, on the receiver side during DWPT, with a fluctuation rate of +/−4% or less, while the receiver side is moved over the transmitter side such that the receiver side receives power from the transmitter side as it moves over the transmitter side,
the compensation inductor being identical to the receiver coil, and
each transmitter coil of the plurality of transmitter coils being identical to the receiver coil.
2. The system according to claim 1 , the secondary compensation network further comprising: a first series resonant capacitor disposed in series with the receiver coil; and a second series resonant capacitor disposed in series with the first series resonant capacitor.
3. The system according to claim 1 , the transmitter side further comprising: a plurality of parallel resonant capacitors disposed in parallel with the plurality of transmitter coils, respectively; and a plurality of resonant inductors disposed in series with the plurality of transmitter coils, respectively.
4. The system according to claim 1 , the transmitter coils and the receiver coil having a first mutual inductance during DWPT, and
the transmitter coils and the compensation inductor having a second mutual inductance during DWPT, and
the system being configured such that a sum of the first mutual inductance and the second mutual inductance is stable within a predetermined stability limit during DWPT.
5. The system according to claim 1 , the receiver side being disposed on an electric vehicle (EV).
6. A method for DWPT, the method comprising:
providing the system according to claim 1 ; and
moving the receiver side over the transmitter side such that the receiver side receives power from the transmitter side as it moves over the transmitter side,
the transmitter coils and the receiver coil having a first mutual inductance during the DWPT, and
the transmitter coils and the compensation inductor having a second mutual inductance during the DWPT.
7. The method according to claim 6 , a sum of the first mutual inductance and the second mutual inductance being stable within a predetermined stability limit during the DWPT.
8. The method according to claim 6 , the receiver side being disposed on an electric vehicle (EV), and
the moving of the receiver side over the transmitter side comprising driving the EV over the transmitter side.
9. A method for designing a system for dynamic wireless power transfer (DWPT) that comprises:
a transmitter side configured to wirelessly transmit power to a receiver coil during DWPT, the transmitter side comprising a plurality of transmitter coils; and
a receiver side configured to wirelessly receive power from the transmitter side during DWPT, the receiver side comprising the receiver coil and a secondary compensation network that comprises a compensation inductor integrated with the receiver coil and disposed in parallel with the receiver coil,
the compensation inductor, the receiver coil, and each transmitter coil of the plurality of transmitter coils all having a same outer length as each other and a same inner length as each other,
the method comprising the following steps, in order:
i) setting the outer length and the inner length for the compensation inductor, the receiver coil, and each transmitter coil of the plurality of transmitter coils;
ii) setting a first distance between adjacent transmitter coils of the plurality of transmitter coils;
iii) setting a second distance between the receiver coil and the compensation inductor;
iv) adding a first mutual inductance between the transmitter coils and the receiver coil to a second mutual inductance between the transmitter coils and the compensation inductor, to obtain a summed mutual inductance;
v) determining whether the summed mutual inductance is stable within a predetermined stability limit;
vi) upon determining that the summed mutual inductance is not stable within the predetermined stability limit, returning to step ii);
vii) upon determining that the summed mutual inductance is stable within the predetermined stability limit, determining whether a fluctuation rate of an output voltage of the system, on the receiver side during the DWPT, is within a predetermined fluctuation limit;
viii) upon determining that the fluctuation rate of the output voltage is not within the predetermined fluctuation limit, returning to step ii);
ix) upon determining that the fluctuation rate of the output voltage is within the predetermined fluctuation limit, determining that the first distance and the second distance are final values for the system with the set outer length and the set inner length for the compensation inductor, the receiver coil, and each transmitter coil of the plurality of transmitter coils.
10. The method according to claim 9 , the predetermined fluctuation limit being +/−4%.
11. The method according to claim 9 , the receiver side being disposed on an electric vehicle (EV).
12. A system for dynamic wireless power transfer (DWPT), the system comprising:
a transmitter side configured to wirelessly transmit power to a receiver coil during DWPT, the transmitter side comprising a plurality of transmitter coils; and
a receiver side configured to wirelessly receive power from the transmitter side during DWPT, the receiver side comprising the receiver coil,
the receiver side further comprising a secondary compensation network comprising a compensation inductor integrated with the receiver coil and disposed in parallel with the receiver coil,
the compensation inductor being identical to the receiver coil,
each transmitter coil of the plurality of transmitter coils being identical to the receiver coil,
the secondary compensation network further comprising: a first series resonant capacitor disposed in series with the receiver coil; and a second series resonant capacitor disposed in series with the first series resonant capacitor,
the transmitter side further comprising: a plurality of parallel resonant capacitors disposed in parallel with the plurality of transmitter coils, respectively; and a plurality of resonant inductors disposed in series with the plurality of transmitter coils, respectively,
the transmitter coils and the receiver coil having a first mutual inductance during DWPT,
the transmitter coils and the compensation inductor having a second mutual inductance during DWPT,
the system being configured such that a sum of the first mutual inductance and the second mutual inductance is stable within a predetermined stability limit during DWPT,
the receiver side being disposed on an electric vehicle (EV), and
the system being configured to produce an output voltage, on the receiver side during DWPT, with a fluctuation rate of +/−4% or less.
13. A method for DWPT, the method comprising:
providing the system according to claim 12 ; and
moving the receiver side over the transmitter side such that the receiver side receives power from the transmitter side as it moves over the transmitter side,
the fluctuation rate of the output voltage, on the receiver side during the DWPT, being +/−4% or less.