Power management in electric vehicles
Various techniques described herein relate to electric vehicle power management system for managing a plurality of battery modules in a battery pack. Such electric vehicle power management system may include a plurality of battery management systems corresponding to a plurality of battery modules, and an energy management system for managing the plurality of battery management systems. The energy management system and the plurality of battery management systems may adopt master-slave wireless communication, and may use a single wireless frequency channel or a plurality of assigned wireless frequency channels.
1. An electric vehicle power management system used for managing a plurality of battery modules, the electric vehicle power management system comprising:
a plurality of battery modules;
a plurality of battery management systems, each said battery management system comprising a battery management processor and a battery management communication module configured to communicate via a unique wireless frequency channel, wherein each of the plurality of battery management systems is connected to a corresponding battery module and is configured to manage one or more battery cells of its corresponding battery module;
an energy management system comprising an energy management processor and an energy management communication module, wherein the energy management system is configured to:
determine a first wireless frequency channel from a plurality of wireless frequency channels in a wireless data channel, the determined first wireless frequency channel corresponding to the unique wireless frequency channel of a first selected battery management system; and
transmit a first command to the first selected battery management system using the determined first wireless frequency channel;
wherein each of the plurality of battery management systems is further configured to use its respective battery management processor and battery management communication module to:
receive commands from the energy management system transmitted via its respective unique wireless frequency channel; and
upon receiving a command from the energy management system transmitted via its respective unique wireless frequency channel, process and respond to the received command.
2. The electric vehicle power management system of claim 1 , wherein the first command includes a unique address identifying the first selected battery management system.
3. The electric vehicle power management system of claim 1 , wherein the first command does not include a unique identifier associated with the first selected battery management system.
4. The electric vehicle power management system of claim 1 , wherein each of the plurality of wireless frequency channels corresponds to a unique battery management system address associated with one of the plurality of battery management systems.
5. The electric vehicle power management system of claim 1 , wherein the energy management system is further configured to:
before transmitting the first command to the first selected battery management system, transmit a verification signal;
receive a response to the verification signal from the first selected battery management system; and
determine whether there is an abnormality associated with the first selected battery management system based on the response received to the verification signal.
6. The electric vehicle power management system of claim 5 , wherein the energy management system is further configured to:
upon determining that there is an abnormality associated with the first selected battery management system, perform a fault diagnosis process.
7. The electric vehicle power management system of claim 1 , wherein the energy management system is further configured to:
receive a response to the first command from the first selected battery management system;
after receiving the response from the first selected battery management system, determine a second wireless frequency channel from the plurality of wireless frequency channels in the wireless data channel, the determined second wireless frequency channel corresponding to the unique wireless frequency channel of a second selected battery management system; and
transmit a second command to the second selected battery management system using the determined second wireless frequency channel.
8. The electric vehicle power management system of claim 7 , wherein the energy management system is further configured to:
set a communication interval time;
identify a first time corresponding to the termination of communications between the energy management system and the first selected battery management system; and
determine a time for the transmission of the second command, based on the identified first time and the communication interval time.
9. The electric vehicle power management system of claim 1 , further comprising:
an external data bus connected to the energy management system, the external data bus configured to transmit communication data from the energy management system and to receive communication data for the energy management system,
wherein the external data bus is configured for bidirectional communication with at least one of a vehicle control unit, a charging unit, or a user interface.