Apparatus and system for balancing energy in battery pack
An apparatus and a system for balancing energy in a battery pack are provided, to implement balanced energy distribution among individual batteries in a battery pack. The apparatus includes: a transmitting coil, configured to transmit an electromagnetic wave generated by an input first alternating current to multiple receiving coils; the multiple receiving coils, where parameter values of all receiving coils of the multiple receiving coils are the same, all the receiving coils are coupled to the transmitting coil at a same coupling strength, and each receiving coil is configured to receive the electromagnetic wave transmitted by the transmitting coil, and generate and output a second alternating current according to the electromagnetic wave.
1. An apparatus for balancing energy in a battery pack, comprising:
a transmitting coil configured to:
input a first alternating current; and
transmit an electromagnetic wave generated by the first alternating current to multiple receiving coils;
the multiple receiving coils, wherein parameter values of all receiving coils of the multiple receiving coils are the same, all the receiving coils are coupled to the transmitting coil in an electromagnetic induction manner at a same coupling strength, and each receiving coil is configured to:
receive the electromagnetic wave transmitted by the transmitting coil; and
generate and output a second alternating current according to the electromagnetic wave, wherein:
coil types of all the receiving coils are the same;
vertical distances from the receiving coils to the transmitting coil are the same; and
among the receiving coils, distances between every two adjacent receiving coils are the same; and
multiple rectifiers, wherein the multiple rectifiers are connected to the multiple receiving coils in a one-to-one correspondence, and each of the multiple rectifiers is configured to:
convert the second alternating current into a direct current; and
output the direct current to one individual battery in a battery pack, wherein the multiple rectifiers and multiple individual batteries in the battery pack are in a one-to-one correspondence.
2. The apparatus according to claim 1 , further comprising:
a first coupling capacitor, connected to the transmitting coil, and configured to:
remove a direct current component from the input first alternating current; and
output, to the transmitting coil, the first alternating current from which the direct current component is removed; and
multiple second coupling capacitors, connected to the multiple rectifiers in a one-to-one correspondence and connected to the multiple receiving coils in a one-to-one correspondence, wherein each of the multiple second coupling capacitors is configured to:
remove a direct current component from the second alternating current; and
output, to one of the multiple rectifiers, the second alternating current from which the direct current component is removed.
3. The apparatus according to claim 1 , wherein that parameter values of all receiving coils of the multiple receiving coils are the same comprises:
numeric values of inductance values of the receiving coils are the same, and
resistance values of parasitic resistors of the receiving coils are the same.
4. The apparatus according to claim 1 , wherein a waveform of the first alternating current is a rectangular wave or a sine wave.
5. A system for balancing energy in a battery pack, comprising:
a controlled alternating current source configured to generate and output a first alternating current;
an apparatus for balancing energy in the battery pack, separately connected to the controlled alternating current source and the battery pack, and configured to:
input the first alternating current that is output by the controlled alternating current source;
generate multiple direct currents after processing the first alternating current; and
respectively output the multiple direct currents to multiple individual batteries in the battery pack, wherein the multiple direct currents are in a one-to-one correspondence with the multiple individual batteries; and
the battery pack, connected to the apparatus, and configured to input the multiple direct currents that are output by the apparatus for balancing energy in the battery pack;
wherein the apparatus comprises:
a transmitting coil, configured to:
input a first alternating current; and
transmit an electromagnetic wave generated by the first alternating current to multiple receiving coils;
the multiple receiving coils, wherein parameter values of all receiving coils of the multiple receiving coils are the same, all the receiving coils are coupled to the transmitting coil in an electromagnetic induction manner at a same coupling strength, and each receiving coil is configured to:
receive the electromagnetic wave transmitted by the transmitting coil; and
generate and output a second alternating current according to the electromagnetic wave, wherein:
coil types of all the receiving coils are the same;
vertical distances from the receiving coils to the transmitting coil are the same; and
among the receiving coils, distances between every two adjacent receiving coils are the same; and
multiple rectifiers, wherein the multiple rectifiers are connected to the multiple receiving coils in a one-to-one correspondence, and each of the multiple rectifiers is configured to:
convert the second alternating current into a direct current; and
output the direct current to one individual battery in a battery pack, wherein the multiple rectifiers and multiple individual batteries in the battery pack are in a one-to-one correspondence.
6. The system according to claim 5 , wherein:
at least one individual battery in the battery pack is connected to the controlled alternating current source;
the at least one individual battery provides a power source to the controlled alternating current source; and
the power source is used by the controlled alternating current source to generate the first alternating current.
7. The system according to claim 5 , further comprising:
another battery pack other than the battery pack, the another battery pack connected to the controlled alternating current source and configured to provide a power source to the controlled alternating current source, wherein the power source is used by the controlled alternating current source to generate the first alternating current.
8. The system according to claim 5 , the apparatus further comprises:
a first coupling capacitor connected to the transmitting coil, the first coupling capacitor configured to:
remove a direct current component from the input first alternating current; and
output, to the transmitting coil, the first alternating current from which the direct current component is removed; and
multiple second coupling capacitors connected to the multiple rectifiers in a one-to-one correspondence and connected to the multiple receiving coils in a one-to-one correspondence, wherein each of the multiple second coupling capacitors is configured to:
remove a direct current component from the second alternating current; and
output, to one of the multiple rectifiers, the second alternating current from which the direct current component is removed.
9. The system according to claim 5 , wherein that parameter values of all receiving coils of the multiple receiving coils are the same comprises:
numeric values of inductance values of the receiving coils are the same, and
resistance values of parasitic resistors of the receiving coils are the same.
10. The system according to claim 5 , wherein a waveform of the first alternating current is a rectangular wave or a sine wave.