Power supply circuit capable of preventing low voltage ride through and wind power converter
By designing a power supply circuit that protects against low-voltage ride-through, and utilizing a combination of controllers and switching devices, the reliability of the UPS front-end contactor is improved in the event of a high-voltage drop in the wind power converter.
Patent Information
- Application Number
- CN202423233598.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2034-12-26
AI Technical Summary
When the high voltage drop on the primary side of the auxiliary power supply of the existing wind power converter is too large and lasts for too long, the UPS front-end contactor is prone to damage, which leads to the coil overheating and damage.
Design a power supply circuit that protects against low voltage ride-through, including a controller, an uninterruptible power supply (UPS), and first and second switching switches. By controlling the first switch body to be energized, the first normally open contact is closed to ensure that the UPS is energized, and the second normally open contact supplies power to the UPS, thus preventing the first switching switch from being damaged during high voltage drops.
It effectively prevents damage to the UPS front-end contactor coil and improves the reliability of the wind power converter.
Smart Images
Figure CN223942407U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wind power converter technology, and in particular to a power supply circuit and wind power converter that are protected against low voltage ride-through. Background Technology
[0002] In the current auxiliary power design of wind power converters, the front-end contactor of the UPS (Uninterruptible Power Supply) is usually powered by the mains. The wind power converter operates under normal low voltage ride-through conditions of the grid for a short period of time, which has little impact on the auxiliary power contactor above 400V. However, if the high voltage drop on the primary side of the auxiliary power is too large and lasts for too long, the UPS front-end contactor will be unable to engage for a long time, and the leakage flux will increase, causing the coil to overheat and be damaged. Utility Model Content
[0003] This application provides a power supply circuit and wind power converter that are protected against low voltage ride-through, so as to prevent damage to the UPS front-end contactor coil when the high voltage drop on the auxiliary power primary side is too large and lasts for too long.
[0004] This application provides a power supply circuit that prevents low voltage ride-through. The power supply circuit includes a controller, an uninterruptible power supply, a first switching switch, and a second switching switch. The first switching switch includes a first switch body and a first normally open contact. The second switching switch includes a second switch body, a second normally open contact, and a normally closed contact.
[0005] The first switch body is connected in series with the normally closed contact and then connected between the first control terminal and the second control terminal of the controller.
[0006] The first power input terminal of the uninterruptible power supply is connected to the first power terminal of the AC power supply, one end of the first normally open contact is connected to the second power terminal of the AC power supply, the other end of the first normally open contact is connected to the second power input terminal of the uninterruptible power supply, and the second normally open contact is connected in parallel with the first normally open contact; the second switch body is connected between the first power output terminal and the second power output terminal of the uninterruptible power supply.
[0007] In one example, the controller is used to control the first switch body to be energized.
[0008] In one example, the AC power source includes mains power.
[0009] In one example, the first power terminal of the AC power supply is the neutral wire of the mains power, and the second power terminal of the AC power supply is the live wire of the mains power.
[0010] In one example, the first or second switching switch includes a relay or a contactor.
[0011] In one example, the uninterruptible power supply includes an energy storage device.
[0012] This application also provides a wind power converter, which includes the aforementioned power supply circuit for preventing low voltage ride-through.
[0013] The power supply circuit and wind power converter provided above with low voltage ride protection can prevent damage to the front-end contactor coil when the high voltage drop on the auxiliary power primary side is too large and lasts for too long, thereby improving the reliability of the product. Attached Figure Description
[0014] Figure 1 A schematic diagram of a power supply circuit for preventing low-voltage ride-through provided in an embodiment of this application.
[0015] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0016] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer and more understandable, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit the scope of this application.
[0017] In the description of this application, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," and "right," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0018] like Figure 1 As shown, this application provides a wind power converter, including a power supply circuit for low voltage ride-through protection. The power supply circuit includes a controller, an uninterruptible power supply (UPS), a first switching switch, and a second switching switch. The first switching switch includes a first switch body K10 and a first normally open contact K11, and the second switching switch includes a second switch body K20, a second normally open contact K21, and a normally closed contact K22.
[0019] The first switch body K10 and the normally closed contact K22 are connected in series and then connected between the first control terminal (shown as 1 in the controller in the figure) and the second control terminal (shown as 2 in the controller in the figure) of the controller.
[0020] The first power input terminal N1 of the uninterruptible power supply (UPS) is connected to the first power input terminal N of the AC power supply. One end of the first normally open contact K11 (shown as 1 in the figure) is connected to the second power input terminal L of the AC power supply. The other end of the first normally open contact K11 (shown as 2 in the figure) is connected to the second power input terminal L1 of the UPS. The second normally open contact K21 is connected in parallel with the first normally open contact K11. The second switch body K20 is connected between the first power output terminal N2 and the second power output terminal L2 of the UPS.
[0021] In one example, a controller is used to energize the first switch body K10.
[0022] In one example, the AC power supply includes mains power, the first power terminal N of the AC power supply is the neutral wire of the mains power, and the second power terminal L of the AC power supply is the live wire of the mains power.
[0023] In one example, the first or second switching switch includes a relay or a contactor.
[0024] In one example, the uninterruptible power supply includes an energy storage device.
[0025] The working principle of this circuit is roughly as follows:
[0026] When the wind turbine converter is powered on, the controller in the wind turbine converter energizes the coil in the first switch body K10 of the upstream contactor, causing the first normally open contact K11 to close. At this time, the uninterruptible power supply (UPS) is powered on, which in turn energizes the coil in the second switch body K20, causing the second normally open contact K21 to close and the normally closed contact K22 to open. The power grid then supplies power to the UPS through the second normally open contact K21. This allows the first transfer switch to disconnect from the power grid after power-on, preventing damage to the first transfer switch in the event of a large and prolonged high voltage drop on the auxiliary power primary side.
[0027] The preferred embodiments of this application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and spirit of this application shall be within the scope of the claims.
Claims
1. A power supply circuit for preventing low-voltage ride-through, characterized in that, The power supply circuit includes a controller, an uninterruptible power supply, a first switching switch and a second switching switch. The first switching switch includes a first switch body and a first normally open contact. The second switching switch includes a second switch body, a second normally open contact and a normally closed contact. The first switch body is connected in series with the normally closed contact and then connected between the first control terminal and the second control terminal of the controller. The first power input terminal of the uninterruptible power supply is connected to the first power terminal of the AC power supply, one end of the first normally open contact is connected to the second power terminal of the AC power supply, the other end of the first normally open contact is connected to the second power input terminal of the uninterruptible power supply, and the second normally open contact is connected in parallel with the first normally open contact; the second switch body is connected between the first power output terminal and the second power output terminal of the uninterruptible power supply.
2. The power supply circuit for preventing low-voltage ride-through according to claim 1, characterized in that, The controller is used to control the first switch body to be energized.
3. The power supply circuit for preventing low-voltage ride-through according to claim 1, characterized in that, The AC power source includes mains power.
4. The power supply circuit for preventing low-voltage ride-through according to claim 3, characterized in that, The first power terminal of the AC power supply is the neutral wire of the mains power, and the second power terminal of the AC power supply is the live wire of the mains power.
5. The power supply circuit for preventing low-voltage ride-through according to claim 1, characterized in that, The first or second switching switch includes a relay or a contactor.
6. The power supply circuit for preventing low-voltage ride-through according to claim 1, characterized in that, The uninterruptible power supply includes an energy storage device.
7. A wind power converter, characterized in that, The wind power converter includes the power supply circuit for preventing low voltage ride-through as described in any one of claims 1-6.