Controlling batteries for electric bus
An onboard charging system for an electric vehicle is configured to communicate with a power supply through exchange of control signals on a power supply line by modulating a charging current being supplied to the charging system. The charging system is capable of communicating fault and battery parameter data to the power supply, as well as a requested charging current used to regulate the power supply output. The power supply may convert high voltage AC power into a controllable DC output supplied directly to the electric vehicle, thereby providing a convenient means for the vehicle to initiate charging during operations. Connection between the electric vehicle and the power supply may be effected using an extendible and retractable electrical connection, such as a mechanical pantograph.
1. A charge control system for one or more energy storage devices, comprising:
a power supply line connectable to a power supply to transmit a charge current for the one or more energy storage devices;
a charge controller configured to monitor one or more parameters indicative of respective states of charge in the one or more energy storage devices and to control the charge current for the one or more energy storage devices based on the one or more monitored parameters; and
a communication subsystem coupled to the power supply line and the charge controller, the communication subsystem configured to receive control signals generated by the charge controller and to modulate the received control signals into the charge current on the power supply line for transmission to the power supply.
2. The system of claim 1 , wherein the communication subsystem is further configured to detect charge current modulations in the charge current on the power supply line, the charge current modulations representing control signals generated by the power supply, and to generate control signals for execution by the charge controller based on the detected charge current modulations.
3. The system of claim 1 , wherein the charge current comprises:
a direct current (DC) component corresponding to a requested charging current for the one or more energy storage devices, the DC component supplied by the power supply in response to the control signals generated by the charge controller; and
an alternating current (AC) component corresponding to modulations of the control signals superimposed onto the DC component by the communication subsystem.
4. The system of claim 1 , wherein the charge control system is installed on a mobile transport vehicle, and the power supply comprises a high voltage source situated externally to the mobile transport.