초록 ▼

A system and method of controlling a multi-phase DC-DC converter having a first phase-leg and a second phase-leg using a single current sensor and a controller is provided. The single current sensor senses an amount of current flowing through the direct current link. Based on the amount of current s

A system and method of controlling a multi-phase DC-DC converter having a first phase-leg and a second phase-leg using a single current sensor and a controller is provided. The single current sensor senses an amount of current flowing through the direct current link. Based on the amount of current sensed, the controller controls current flowing through the first phase-leg as well as current flowing through the second phase-leg.

대표청구항 ▼

1. A control system for controlling a first phase-leg and a second phase-leg connected in parallel in a DC-DC converter between a battery and a direct current (DC) link, the control system comprising: single current sensor generating a sensor signal indicating an amount of current flowing through th

1. A control system for controlling a first phase-leg and a second phase-leg connected in parallel in a DC-DC converter between a battery and a direct current (DC) link, the control system comprising: single current sensor generating a sensor signal indicating an amount of current flowing through the direct current link, including an amount of current flowing through the first phase-leg during a first time interval and an amount of current flowing through the second phase-leg during a second time interval; andcontroller configured to receive the sensor signal from the single current sensor and generate and transmit a first command signal to the first phase-leg and a second command signal to the second phase-leg;whereby the first command signal controls current flowing through the first phase-leg, and the second command signal controls current flowing through the second phase-leg;wherein the controller redistributes the current between the first phase-leg and the second phase-leg to dissipate unequal amounts of heat in the first phase-leg and the second phase-leg. 2. The control system of claim 1 wherein the controller transmits the first command signal and the second command signal to change the amount current flowing through the first phase-leg to be different from the amount of current flowing through the second phase-leg. 3. The control system of claim 1 wherein the first command signal includes a first switching signal and a second switching signal, and the second command signal includes a third switching signal and a fourth switching signal, the first switching signal controlling a first switch in the first phase-leg, the second switching signal controlling a second switch in the first phase-leg, the third switching signal controlling a third switch in the second phase-leg, and the fourth switching signal controlling a fourth switch in the second phase-leg. 4. The control system of claim 3 wherein the first switching signal complements the second switching signal and the third switching signal complements the fourth switching signal. 5. The control system of claim 3 wherein the first switching signal switches the first switch to an off-state, the second switching signal switches the second switch to an on-state, the third switching signal switches the third switch to the on-state, and the fourth switching signal switches the fourth switch to the off-state to allow the single current sensor to sense the amount of current flowing through the direct current link and generate the sensor signal indicating the amount of current flowing through the first phase-leg during the first time interval. 6. The control system of claim 5 wherein the amount of current flowing through the first phase-leg indicates an amount of current flowing through an inductor in the first phase-leg. 7. The control system of claim 3 wherein the first switching signal switches the first switch to an on-state, the second switching signal switches the second switch to an off-state, the third switching signal switches the third switch to the off-state, and the fourth switching signal switches the fourth switch to the on-state to allow the single current sensor to sense the amount of current flowing through the direct current link and generate the sensor signal indicating the amount of current flowing through the second phase-leg during the second time interval. 8. The control system of claim 7 wherein the amount of current flowing through the second phase-leg indicates an amount of current flowing through an inductor in the second phase-leg. 9. The control system of claim 1 wherein the controller generates the first command signal and the second command signal to redistribute the current between the first phase-leg and the second phase-leg in response to the target amount of current for the first phase-leg and the target amount of current for the second phase-leg. 10. The control system of claim 1 wherein the single current sensor senses the amount of current flowing through the direct current link using a center-aligned pulse-width modulation (PWM) scheme. 11. The control system of claim 10 wherein the single current sensor senses the amount of current flowing through the direct current link at a switching frequency between 5 and 20 kHz. 12. The control system of claim 11 wherein the switching frequency is 10 kHz. 13. The control system of claim 1 wherein the controller is configured to generate and transmit the first and second command signals in an effort to prevent ripple current flow from reversing direction in at least one of the phase legs. 14. The control system of claim 1 wherein the controller compares the amount of current flowing through the first phase-leg to a target amount of current for the first phase-leg to generate the first command signal and the amount of current flowing through the second phase-leg to a target amount of current for the second phase-leg to generate the second command signal. 15. The control system of claim 1 wherein the target amounts of current for the first and second phase-legs are different from each other. 16. A control system for controlling a first phase-leg and a second phase-leg, the first and second phase-legs being connected in parallel between a battery and a direct current (DC) link, the control system comprising: a single current sensor configured to sense an amount of current flowing through the direct current link using a center-aligned pulse-width modulation (PWM) scheme and generate a sensor signal indicating the amount of current flowing through the direct current direct current link, the sensor signal indicating an amount of current flowing through the first phase-leg during a first time interval and an amount of current flowing through the second phase-leg during a second time interval; anda controller configured to receive the sensor signal from the single current sensor, compare the amount of current flowing through the first phase-leg to a target amount of current for the first phase-leg to generate and transmit a first command signal to the first phase-leg, and compare the amount of current flowing through the second phase-leg to a target amount of current for the second phase-leg to generate and transmit a second command signal to the second phase-leg;whereby the first command signal includes a first switching signal and a second switching signal, and the second command signal includes a third switching signal and a fourth switching signal, the first switching signal controlling a first switch in the first phase-leg, the second switching signal controlling a second switch in the first phase-leg, the third switching signal controlling a third switch in the second phase-leg, and the fourth switching signal controlling a fourth switch in the second phase-leg to control the amount of current flowing through the first phase-leg and the amount of current flowing through the second phase-leg;wherein the controller redistributes the current between the first phase-leg and the second phase-leg to dissipate unequal amounts of heat in the first phase-leg and the second phase-leg. 17. The control system of claim 16 wherein during the first time interval the first switching signal switches the first switch to an off-state, the second switching signal switches the second switch to an on-state, the third switching signal switches the third switch to the on-state, and the fourth switching signal switches the fourth switch to the off-state, and during the second time interval the first switching signal switches the first switch to the on -state, the second switching signal switches the second switch to the off-state, the third switching signal switches the third switch to the off-state, and the fourth switching signal switches the fourth switch to the on-state to allow the single current sensor to sense the amount of current flowing through the direct current link during the time intervals and generate the sensor signal indicating the amount of current flowing through the first phase-leg during the first time interval and the amount of current flowing through the second phase-leg during the second time interval. 18. The control system of claim 17 wherein the controller generates the first switching signal, the second switching signal, the third switching signal, and the fourth switching signal to change the amount of current flowing through the first phase-leg to be different from the amount of current flowing through the second phase-leg in response to the target amount of current for the first phase-leg and the target amount of current for the second phase-leg being different from each other. 19. A method of controlling a first phase-leg and a second phase-leg connected in parallel in a DC-DC converter between a battery and a direct current (DC) link, the method comprising: detecting respective currents flowing through the first and second phase-legs during respective first and second time intervals using a single current sensor in the direct current link;comparing the respective currents to respective target amounts of current for the first and second phase-legs, the target amounts of current for the first and second phase-legs being different from each other; andcontrolling the first and second phase-legs in response to comparing the respective currents to the respective target amounts;whereby the controlling the first and second phase-legs controls the respective currents flowing through the first and second phase-legs to be different from each other to dissipate unequal amounts of heat in the first and second phase-legs. 20. The method of claim 19 wherein the controlling the first and second phase-legs changes the respective currents flowing through the first and second phase-legs in an effort to prevent ripple current flow from reversing direction in at least one of the phase legs.