Contactor supply bus

Abstract

A vehicle includes an inverter. The vehicle includes a contactor power bus configured to supply power to latch mechanisms of main contactors and pre-charge contactors associated with the inverter. The vehicle includes a controller configured to maintain operation of the inverter and generate a sensor fault. The operation of the inverter can be maintained in response to sensor outputs indicating that different portions of the contactor power bus are energized and de-energized.

Description

Technical Field

[0001] The present disclosure relates to a contactor supply bus. Background Art

[0002] The vehicle may include a contactor or switch for connecting and disconnecting the energy source from the inverter. The contactor may be driven by a contactor supply bus. The controller may be configured to monitor the bus for de-energization. False alarms associated with de-energization may be generated by a single point indication. Summary of the invention

[0003] A vehicle includes an inverter. The vehicle includes a contactor power bus configured to supply power to a latch mechanism of a main contactor and a pre-charge contactor associated with the inverter. The vehicle includes a controller configured to maintain operation of the inverter and generate a sensor fault. The operation of the inverter can be maintained in response to a sensor output indicating that different parts of the contactor power bus are energized and de-energized. One of the parts can include a contact between the contactor power bus and the latch mechanism of the pre-charge contactor. Another of the parts can include a contact between the contactor power bus and the controller. Maintaining the operation of the inverter includes operating a driver to supply the latch mechanism of the main contactor with a duty cycle greater than half. The duty cycle can be 100%. A Zener diode can be arranged with the driver to prevent overvoltage of a transistor of the driver in response to the sensor output indicating that different parts of the contactor power bus are energized and de-energized.

[0004] A method includes maintaining operation of an inverter by a controller in response to sensor outputs indicating different portions of a contactor power bus being energized and deenergized, the contactor power bus being configured to supply power to latch mechanisms of main contactors and pre-charge contactors associated with an inverter of a vehicle. The method includes generating a sensor fault in response to the sensor outputs indicating different portions of the contactor power bus being energized and deenergized.

[0005] A vehicle includes a load. The vehicle includes a contactor power bus configured to supply power to a latch mechanism of a main contactor and a pre-charge contactor associated with the load. The vehicle includes a controller configured to maintain operation of the load and generate a sensor fault. The operation of the load is maintained in response to a sensor output indicating that a pre-charge latch mechanism portion of the contactor power bus and a contactor power bus contact are energized and de-energized, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1is a schematic diagram of a vehicle including a load;

[0007] Figure 2 is a schematic diagram of a controller configured to energize a contactor; and

[0008] Figure 3 is an algorithm for detecting power loss on the bus. DETAILED DESCRIPTION

[0009] Embodiments of the present disclosure are described herein. However, it will be understood that the disclosed embodiments are merely examples, and other embodiments may take various and alternative forms. The drawings are not necessarily drawn to scale; some features may be exaggerated or minimized to show the details of a particular component. Therefore, the specific structural and functional details disclosed herein should not be interpreted as restrictive, but only as a representative basis for teaching those skilled in the art to adopt the present invention in various ways. As will be understood by those of ordinary skill in the art, the various features shown and described with reference to any one of the accompanying drawings may be combined with the features shown in one or more other drawings to produce embodiments that are not explicitly shown or described. The combination of features shown provides representative embodiments for typical applications. However, various combinations and modifications of features consistent with the teachings of the present disclosure may be required for specific applications or implementations.

[0010] Modern electric and hybrid vehicles include contactors to selectively energize vehicle loads. For example, a battery system can be configured to selectively energize an inverter or other load that operates an electric motor or traction motor. The inverter can be connected in parallel with a DC link capacitor. A pre-charge contactor circuit can be used to charge the DC link capacitor before the main contactor circuit is engaged to reduce system shock.

[0011] The pre-charge contactor and the main contactor can be operated by a latching mechanism or other means of controlling the contactor power bus to be excited. The input of the sensor or controller can be used to determine the contactor power bus excitation. The sensor or input can be an analog or digital input of the controller. Due to different power and usage requirements, the pre-charge contactor driver can have a different operation from the main contactor driver. The unique operation of the pre-charge contactor driver can allow detection of contactor power bus excitation when contactor power bus excitation is not used, which improves the robustness of the monitoring system by adding additional and previously unused contactor power bus sensor positions.

[0012] refer to Figure 1, a vehicle 100 is shown. The vehicle 100 includes a power supply system including a high voltage battery 104 and a high voltage vehicle load 106, which may include an inverter. As shown, the system includes two main contactors 110, 120 to selectively connect and disconnect the high voltage vehicle load 106 to a power source and ground. The pre-charge contactor 130 is configured to charge the DC link capacitor while limiting the current flowing from the battery 104 to the load 106 until the DC link capacitor voltage is sufficiently similar to the battery 104 voltage.

[0013] Each of the contactors 110, 120, 130 includes a corresponding latching mechanism 112, 122, 132 for operating a switch. Any type of latching mechanism 112, 122, 132 may be used. For example, a solenoid latching mechanism or other relay latching mechanism may be used. In other embodiments, a steady-state switch may be used. Any type of contactor, switch, or connection mechanism may be used to complete a circuit having a pre-charge loop and a main loop.

[0014] The latch mechanisms 112, 122, 132 are each independently driven by the controller 170 from the drivers 172, 174, 176, respectively. Additional controllers or combinations of controllers may be used. The main contactor drivers 172, 174 may be configured differently than the pre-charge contactor driver 176. For example, the main contactor drivers 172, 174 may drive the respective latch mechanisms 112, 122 using pulse width modulation (PWM) signals or other methods, such as Figure 2 The pre-charge contactor driver 176 can operate the latch mechanism using direct current or other methods. Each of the contactors can form an independent circuit using the contactor power bus 150.

[0015] The contactor power bus 150 may have contacts 152, 154, 156, 158 associated with each of the contactor drivers 172, 174, 176, each of which corresponds to a respective portion of the contactor power bus 150. The controller 170 may have contactor power bus contacts 158 connected directly or indirectly to an input of the controller 170. The controller 170 may determine the power availability of the contactor power bus 150 via the controller contacts 158. The pre-charge contactor driver 176 may have a voltage detection circuit detection inherent to the direct actuation of the latch mechanism 132 to determine whether the pre-charge contactor power bus contacts are energized.

[0016] refer to Figure 2, the main contactor 110 is driven by a PWM circuit of a controller 170. The controller may include a control unit 178. The main control unit 178, which is part of the controller 170, includes a contactor power bus measurement circuit 180 to measure the voltage of the contactor power bus junction 158. A recirculation diode 182 may be used with an open circuit detection circuit 184 to detect an open circuit.

[0017] The control unit 178 also provides PWM signals to the MOSFET driver 186 and the low-side driver 192 to operate the contactor 110. The protection circuit includes a latch trigger 188, a comparator 190 for overcurrent protection, and a feedback monitoring circuit that may include an operational amplifier 194 for current feedback. The protection circuit can disable the low-side driver MOSFET 192. The battery Vbat 152 is used to power the contactor power circuit 150. A relay can be used to connect Vbat 152 to the contactor power bus 150 and disconnect Vbat 152 from the contactor power bus 150.

[0018] refer to Figure 3 , an algorithm 200 is shown. The algorithm starts at step 202. In step 204, input information is collected. The collected information can be a contactor power bus contact voltage level or other information used to determine whether a specific portion of the contactor power bus 150 is energized.

[0019] In step 206, the controller 170 may determine whether there is voltage or power at the contactor power bus contact 158. The controller 170 may wait for an indication that the power bus contact 158 ​​is de-energized. If the contactor power bus contact 158 ​​is de-energized, the controller 170 may determine whether the pre-charge contactor power bus contact 156 has power. The pre-charge contactor power bus contact 156 may be fed to the pre-charge contactor driver 176. The pre-charge contactor driver may include an inherent circuit that senses the presence of voltages on the contactor power bus 150 and the pre-charge contactor power bus contact 156. For example, a pre-existing input may be necessary for the pre-charge contactor driver 176. The pre-existing pre-charge contactor driver circuit 176 may be used instead to detect whether power is available at the pre-charge contactor contact 156. If both the indication and the portion (the contactor power bus contact 158 ​​and the pre-charge contactor power bus contact 156) are de-energized, the controller 170 may shut down the inverter. The controller 170 may shut down the inverter by opening the main contactors 110 , 120 or de-energizing the corresponding latching mechanisms 112 , 122 .

[0020] If the pre-charge contactor power bus contact 156 is still energized, the controller 170 will maintain inverter operation by increasing control of the main contactor latching mechanisms 112, 122. The latching mechanisms 112, 122 may be energized at a duty cycle greater than 50%. The latching mechanisms 112, 122 may be energized at a 100% duty cycle. Duty cycle changes may be Figure 2 1, 122 voltages. However, when the recirculating diode 182 is not conducting, it cannot clamp the voltage. In this case, the Zener protection circuit within the MOSFET driver 186 will begin to clamp the driver voltage. The controller 170 can also generate a fault indication to the on-board diagnostic system. The on-board diagnostic system can display the fault to the operator of the vehicle 100. For example, if the contactor power bus 150 is disconnected, then the Zener diode will clamp the voltage. In addition, at the moment this connection is disconnected, the contactor is latched by the controller 170 to protect the system from any possible reconnection made by the controller 170. This means that the reuse of the pre-charged contactor driver 176 helps to maintain system and vehicle operation by identifying that only the contactor bus contact 158 ​​is de-energized, which increases the sensing redundancy of the system without the need for additional chips or parts.

[0021] The words used in this specification are descriptive words rather than restrictive words, and it will be understood that various changes can be made without departing from the spirit and scope of the present disclosure. As previously mentioned, the features of various embodiments can be combined to form other embodiments of the present invention that may not be explicitly described or shown. Although various embodiments may have been described as providing advantages or being preferred in terms of one or more required characteristics compared to other embodiments or prior art implementations, it will be appreciated by those of ordinary skill in the art that one or more features or characteristics can be compromised to achieve the required overall system attributes, depending on the specific application and implementation. These attributes may include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, maintainability, weight, manufacturability, ease of assembly, etc. Therefore, embodiments described as being less than desired in terms of one or more characteristics compared to other embodiments or prior art implementations are not outside the scope of the present disclosure and may be desired for a specific application.

[0022] According to the present invention, a vehicle is provided, the vehicle having: an inverter; a contactor power bus, the contactor power bus being configured to supply power to latching mechanisms of a main contactor and a pre-charge contactor associated with the inverter; and a controller, the controller being configured to maintain operation of the inverter and generate a sensor fault in response to sensor outputs indicating that different portions of the contactor power bus are energized and de-energized.

[0023] According to an embodiment, the above invention is further characterized in that one of the parts comprises a contact between the contactor power bus and the latch mechanism of the pre-charging contactor.

[0024] According to an embodiment, the above invention is further characterized in that another one of the parts comprises a connection point between the contactor power bus and the controller.

[0025] According to an embodiment, the above invention is further characterized in that the maintaining operation includes operating a driver to supply the latch mechanism of the main contactor with a duty cycle greater than half.

[0026] According to an embodiment, the above invention is further characterized in that the duty cycle greater than half is 100%.

[0027] According to an embodiment, the above invention is further characterized by a Zener diode arranged with the driver to prevent overvoltage of transistors of the driver in response to the sensor output indicating that different parts of the contactor power bus are energized and deenergized.

[0028] According to the present invention, a method is provided, the method comprising: maintaining the operation of an inverter by a controller in response to a sensor output indicating that different parts of a contactor power bus are energized and de-energized, the contactor power bus being configured to supply power to a latching mechanism of a main contactor and a pre-charge contactor associated with an inverter of a vehicle; and generating a sensor fault in response to the sensor output indicating that different parts of the contactor power bus are energized and de-energized.

[0029] According to an embodiment, the above invention is further characterized in that one of the parts comprises a contact between the contactor power bus and the latch mechanism of the pre-charging contactor.

[0030] According to an embodiment, the above invention is further characterized in that another one of the parts comprises a connection point between the contactor power bus and the controller.

[0031] According to an embodiment, the above invention is further characterized in that the maintaining operation includes operating a driver to supply the latch mechanism of the main contactor with a duty cycle greater than half.

[0032] According to an embodiment, the above invention is further characterized in that the duty cycle greater than half is 100%.

[0033] According to an embodiment, the above invention is further characterized by a Zener diode arranged with the driver to prevent overvoltage of transistors of the driver in response to the sensor output indicating that different parts of the contactor power bus are energized and deenergized.

[0034] According to the present invention, a vehicle is provided, the vehicle having: a contactor power bus, the contactor power bus being configured to supply power to a latch mechanism of a main contactor and a pre-charge contactor associated with a load; and a controller, the controller being configured to maintain operation of the load and generate a sensor fault in response to a sensor output indicating that a pre-charge latch mechanism portion of the contactor power bus and a contactor power bus contact are energized and de-energized, respectively.

[0035] According to an embodiment, the above invention is further characterized in that one of the parts comprises a contact between the contactor power bus and the latch mechanism of the pre-charging contactor.

[0036] According to an embodiment, the above invention is further characterized in that another one of the parts comprises a connection point between the contactor power bus and the controller.

[0037] According to an embodiment, the above invention is further characterized in that the maintaining operation includes operating a driver to supply the latch mechanism of the main contactor with a duty cycle greater than half.

[0038] According to an embodiment, the above invention is further characterized in that the duty cycle greater than half is 100%.

[0039] According to an embodiment, the above invention is further characterized by a Zener diode arranged with the driver to prevent overvoltage of transistors of the driver in response to the sensor output indicating that different parts of the contactor power bus are energized and deenergized.

Claims

1. A vehicle comprising: a battery, selectively coupled to a vehicle high voltage bus; Inverter; a pre-charge contactor having an associated pre-charge latch mechanism supplied with power by a first portion of the contactor power bus, the pre-charge contactor being configured to selectively couple the DC link capacitor to the vehicle high voltage bus; a main contactor configured to selectively couple the battery to the inverter and having an associated main latching mechanism powered by a second portion of the contactor power bus; as well as A controller is configured to supply power to the primary latch mechanism to maintain operation of the inverter in response to a sensor output indicating that one of the first and second portions of the contactor power bus is energized and the other of the first and second portions is de-energized.

2. The vehicle of claim 1, wherein one of the first portion and the second portion includes a junction between the contactor power bus and the pre-charge latch mechanism of the pre-charge contactor.

3. The vehicle of claim 2, wherein the other of the first portion and the second portion includes a junction between the contactor power bus and the controller. 4 . The vehicle of claim 1 , wherein supplying power to the master latching mechanism comprises operating a driver to supply power to the master latching mechanism at a duty cycle greater than half.

5. The vehicle of claim 4, wherein the greater than half duty cycle is 100%.

6. The vehicle of claim 4 further comprising a Zener diode arranged with the driver to prevent overvoltage of a transistor of the driver in response to the sensor output.

7. A method comprising: Through the controller, maintaining operation of the inverter in response to sensor outputs indicating that different portions of a contactor power bus are respectively energized and de-energized, wherein the contactor power bus is configured to supply power to latch mechanisms of main contactors and pre-charge contactors associated with an inverter of the vehicle; and A sensor fault is generated in response to the sensor output indicating that different portions of the contactor power bus are respectively energized and de-energized.

8. The method of claim 7, wherein one of the portions comprises a junction between the contactor power bus and the latch mechanism of the pre-charge contactor.

9. The method of claim 7, wherein another of the portions comprises a junction between the contactor power bus and the controller.

10. The method of claim 7, wherein maintaining operation includes operating a driver to supply the latch mechanism of the main contactor with a duty cycle greater than half. The method of claim 10 , wherein the duty cycle greater than half is 100%.

12. The method of claim 10, further comprising a Zener diode arranged with the driver to prevent overvoltage of a transistor of the driver in response to the sensor output indicating that different portions of the contactor power bus are respectively energized and de-energized.

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