US-20260128604-A1 - POWER SUPPLY SYSTEM

Abstract

The power supply system includes: a first inverter connected to the first battery via a first positive electrode line and a negative electrode line; a second inverter connected to the second battery via a second positive electrode line and the negative electrode line; a first capacitor connected to the first positive electrode line and the negative electrode line; a second capacitor connected to the second positive electrode line and the negative electrode line; a negative electrode connection relay capable of disconnecting and connecting the negative electrode of the second battery and the negative side power supply line of the second inverter; a charging connector; and a control device for turning on the negative electrode connection relay.

Inventors

• Satoshi ICHIDA

Assignees

• TOYOTA JIDOSHA KABUSHIKI KAISHA

Dates

Publication Date

20260507

Application Date

20251017

Priority Date

20241101

Claims (6)

1. 1 . A power supply system including a first battery and a second battery, the power supply system comprising: a motor including a three-phase coil; a first inverter connected to the first battery via a first positive electrode line and a negative electrode line and connected to one end side of the three-phase coil; a second inverter connected to the second battery via a second positive electrode line and the negative electrode line and connected to another end side of the three-phase coil; a first capacitor connected to the first positive electrode line and the negative electrode line; a second capacitor connected to the second positive electrode line and the negative electrode line; a negative electrode connection relay that is attached to the negative electrode line and that enables and disables connection between a negative electrode terminal of the second battery and a negative side power supply line of the second inverter; a charging connector connected to the first positive electrode line and the negative electrode line and electrically connectable to a charging facility; and a control device that turns on the negative electrode connection relay when discharging the first capacitor or the second capacitor.
2. 2 . The power supply system according to claim 1 , further comprising: a first positive electrode relay that is attached to the first positive electrode line and that enables and disables connection between the first battery and the first inverter and the first capacitor; and a second positive electrode relay that is attached to the second positive electrode line and that enables and disables connection between the second battery and the second inverter and the second capacitor, wherein when discharging the first capacitor, the control device turns on and fixes an upper arm of the first inverter and turns off and fixes a lower arm of the second inverter in a state in which the first and second positive electrode relays are turned off and the negative electrode connection relay is turned on, and when discharging the second capacitor, the control device turns on and fixes a lower arm of the first inverter and turns off and fixes an upper arm of the second inverter in a state in which the first and second positive electrode relays are turned off and the negative electrode connection relay is turned on.
3. 3 . A power supply system including a first battery and a second battery, the power supply system comprising: a motor including a three-phase coil; a first inverter connected to the first battery via a first positive electrode line and a negative electrode line and connected to one end side of the three-phase coil; a second inverter connected to the second battery via a second positive electrode line and the negative electrode line and connected to another end side of the three-phase coil; a first capacitor connected to the first positive electrode line and the negative electrode line; a second capacitor connected to the second positive electrode line and the negative electrode line; a positive electrode connection relay attached to a positive electrode connection line that connects the first positive electrode line and the second positive electrode line; a negative electrode connection relay that is attached to the negative electrode line and that enables and disables connection between a negative electrode terminal of the second battery and a negative side power supply line of the second inverter; a first positive electrode relay that is attached to the first positive electrode line and that enables and disables connection between the first battery and the first inverter and the first capacitor; a second positive electrode relay that is attached to the second positive electrode line and that enables and disables connection between the second battery and the second inverter and the second capacitor; a charging connector connected to the first positive electrode line and the negative electrode line and electrically connectable to a charging facility; and a control device that turns off the first and second positive electrode relays and turns on the positive electrode connection relay and the negative electrode connection relay when discharging the first capacitor and the second capacitor.
4. 4 . The power supply system according to claim 3 , wherein the control device performs pulse width modulation (PWM) control on the first and second inverters in a state in which the first and second positive electrode relays are turned off and the positive electrode connection relay and the negative electrode connection relay are turned on.
5. 5 . The power supply system according to claim 2 , wherein the control device determines whether welding has occurred in at least one of the first and second positive electrode relays based on a voltage of the first capacitor or the second capacitor when being discharged.
6. 6 . The power supply system according to claim 3 , wherein the control device determines whether welding has occurred in at least one of the first and second positive electrode relays based on a voltage of the first capacitor or the second capacitor when being discharged.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to Japanese Patent Application No. 2024-193181 filed on November 1, 2024. The disclosure of the above-identified application, including the specification, drawings, and claims, is incorporated by reference herein in its entirety. BACKGROUND 1. Technical Field The present disclosure relates to a power supply system. 2. Description of Related Art There has been proposed a drive device including first and second power storage devices, a motor including a three-phase coil, and first and second inverters (see Japanese Unexamined Patent Application Publication No. 2020-5394 (JP 2020-5394 A), for example). The first and second inverters are connected to first and second power lines to which the first and second power storage devices are connected, are connected to one end side and the other end side of the three-phase coil, and have a plurality of first and second switching elements. SUMMARY The power supply system includes a motor including a three-phase coil, a first inverter, a second inverter, a first capacitor, and a second capacitor. The first inverter is connected to a first battery via a first positive electrode line and a first negative electrode line, and is connected to one end side of the three-phase coil. The second inverter is connected to a second battery via a second positive electrode line and a second negative electrode line, and is connected to another end side of the three-phase coil. The first capacitor is connected to the first positive electrode line and the first negative electrode line. The second capacitor is connected to the second positive electrode line and the second negative electrode line. In such a power supply system, it is recognized as an important issue to execute stable discharge of the first capacitor or the second capacitor. A main object of the power supply system of the present disclosure is to execute stable discharge of the first capacitor or the second capacitor. In order to achieve the above main object, the power supply system of the present disclosure adopts the following measures. A first aspect of the present disclosure provides a power supply system including a first battery and a second battery, the power supply system including: a motor including a three-phase coil; a first inverter connected to the first battery via a first positive electrode line and a negative electrode line and connected to one end side of the three-phase coil; a second inverter connected to the second battery via a second positive electrode line and the negative electrode line and connected to another end side of the three-phase coil; a first capacitor connected to the first positive electrode line and the negative electrode line; a second capacitor connected to the second positive electrode line and the negative electrode line; a negative electrode connection relay that is attached to the negative electrode line and that enables and disables connection between a negative electrode terminal of the second battery and a negative side power supply line of the second inverter; a charging connector connected to the first positive electrode line and the negative electrode line and electrically connectable to a charging facility; and a control device that turns on the negative electrode connection relay when discharging the first capacitor or the second capacitor. In the thus configured power supply system according to the first aspect of the present disclosure, it is possible to execute stable discharge of the first capacitor or the second capacitor. A second aspect of the present disclosure provides a power supply system including a first battery and a second battery, the power supply system including: a motor including a three-phase coil; a first inverter connected to the first battery via a first positive electrode line and a negative electrode line and connected to one end side of the three-phase coil; a second inverter connected to the second battery via a second positive electrode line and the negative electrode line and connected to another end side of the three-phase coil; a first capacitor connected to the first positive electrode line and the negative electrode line; a second capacitor connected to the second positive electrode line and the negative electrode line; a positive electrode connection relay attached to a positive electrode connection line that connects the first positive electrode line and the second positive electrode line; a negative electrode connection relay that is attached to the negative electrode line and that enables and disables connection between a negative electrode terminal of the second battery and a negative side power supply line of the second inverter; a first positive electrode relay that is attached to the first positive electrode line and that enables and disables connection between the first battery and the first inverter and the first capacitor; a second positive electrode relay tha