The present invention relates to a system and method for preventing overvoltage of a battery using a cell balancing circuit.

An electric vehicle fast charger and methods thereof are described, adapted for re-use of magnetic components of an electric vehicle having traction converters when the electric vehicle is stationary and connected to a power grid. A switching stage provided by one or more sets of switches is controlled complementarily with the switches of the traction converters to (i) provide inversion of a grid voltage and (ii) shape current of the grid current between the electric vehicle and the power grid to track a waveshape of the grid voltage. A single switching stage and a dual switching stage circuit are contemplated, along with switch controller circuits, and instruction sets for switch control. Variants provide for energy transfer to accommodate for energy imbalances between storage devices.

A method includes interpreting a contactor open event and a contactor load value for a contactor positioned on a motive power circuit for a mobile application, determining that a contactor opening event under load has occurred in response to the contactor open event and the contactor load value, and updating a contactor wear condition in response to the contactor opening event under load, wherein updating the contactor wear condition comprises accumulating a number of the contactor opening events under load.

The present disclosure includes an automotive battery system that uses switching devices to increase operational performance and reliability. The battery system includes a battery cell, a primary switching device electrically coupled to a terminal of the battery cell, and a secondary switching device electrically coupled to the terminal of the battery cell and in parallel with the primary switching device. The primary switching device includes an electromechanical switching device that enables charging or discharging of the battery and generates a boosted voltage. A secondary switching device includes a solid-state switching device and a diode, electrically coupled in series, which detect short circuit conditions in a power-efficient manner and remove the short circuit condition by using the boosted voltage to actuate the armature. Furthermore, parallel switching devices work together to deliver appropriate amounts of power as required by an electrical device, increasing the performance, reliability, and life-span of a battery system.

A method includes interpreting a contactor open event and a contactor load value for a contactor positioned on a motive power circuit for a mobile application, determining that a contactor opening event under load has occurred in response to the contactor open event and the contactor load value, and updating a contactor wear condition in response to the contactor opening event under load, wherein updating the contactor wear condition comprises accumulating a number of the contactor opening events under load.

A method of managing power and a power management circuit operable in a plurality of modes are presented. The power management circuit includes a three terminals switching converter coupled to a controller. The switching converter has a single inductor, two sets of switches, a bypass switch and a transition switch. The first set of switches is coupled to an input terminal. The second set of switches is coupled to a battery terminal. The bypass switch is coupled between the battery terminal and a load terminal. The single inductor is provided between a first switching node and a second switching node. The transition switch is provided between the first switching node and the battery or the load terminal. A controller is configured to select a mode of operation by changing a state of at least one of the bypass switch and the transition switch.

A brushless DC motor system control method provided is based on a hybrid energy storage unit. The HESU topology is designed, and the output of the designed HESU is connected to the input of three-phase inverter, and the output of three-phase inverter is connected with the three-phase windings of the BLDCM. In braking operation, two kinds of braking vectors are constructed according to the HESU and three-phase inverter. Moreover, through the combined action of the two vectors, the braking torque control is achieved and meanwhile the braking energy is fed back to the supercapacitor. In electric operation, four kinds of electric vectors are constructed according to the HESU and three-phase inverter. Moreover, the power sharing control between battery and supercapacitor is realized by different vectors action during motor acceleration mode, and the torque ripple in commutation period is suppressed by different vectors action during motor constant speed mode.

A brushless DC motor system control method provided is based on a hybrid energy storage unit. The HESU topology is designed, and the output of the designed HESU is connected to the input of three-phase inverter, and the output of three-phase inverter is connected with the three-phase windings of the BLDCM. In braking operation, two kinds of braking vectors are constructed according to the HESU and three-phase inverter. Moreover, through the combined action of the two vectors, the braking torque control is achieved and meanwhile the braking energy is fed back to the supercapacitor. In electric operation, four kinds of electric vectors are constructed according to the HESU and three-phase inverter. Moreover, the power sharing control between battery and supercapacitor is realized by different vectors action during motor acceleration mode, and the torque ripple in commutation period is suppressed by different vectors action during motor constant speed mode.

A voltage generator circuit can be structured to provide an output voltage having a substantially flat temperature coefficient by use of a circuit loop having transistors and a resistor arranged such that, in operation, current through the resistor has a signed temperature coefficient. The current behavior can be controlled by an output transistor coupled to another transistor, which is coupled to the circuit loop, with this other transistor sized such that, in operation, a voltage of this other transistor has a signed temperature coefficient that is opposite in sign to the signed temperature coefficient of the current through the resistor. Embodiments of voltage generator circuits can also include additional components to trim output voltage, to provide unconditional stability, or other features for the respective voltage generator circuit. In various embodiments, a voltage generator circuit can be implemented as a low drop-out (LDO) voltage regulator.

A voltage generator circuit can be structured to provide an output voltage having a substantially flat temperature coefficient by use of a circuit loop having transistors and a resistor arranged such that, in operation, current through the resistor has a signed temperature coefficient. The current behavior can be controlled by an output transistor coupled to another transistor, which is coupled to the circuit loop, with this other transistor sized such that, in operation, a voltage of this other transistor has a signed temperature coefficient that is opposite in sign to the signed temperature coefficient of the current through the resistor. Embodiments of voltage generator circuits can also include additional components to trim output voltage, to provide unconditional stability, or other features for the respective voltage generator circuit. In various embodiments, a voltage generator circuit can be implemented as a low drop-out (LDO) voltage regulator.