Non-power-outage bus PT capacitance current test resonance eliminator short-circuit device

Abstract

The invention relates to an uninterruptible bus PT capacitance current test resonance eliminator short-circuit device, which comprises an embedded short-circuit module and a PT neutral point current monitoring protection module, the embedded short circuit module comprises a vacuum contactor and a control panel, the vacuum contactor is in short circuit with a resonance eliminator for PT capacitance current testing, and the control panel is used for controlling opening and closing of the vacuum contactor; opening and closing of the vacuum contactor are used for controlling switching of the resonance eliminator. And the PT neutral point current monitoring protection module is used for detecting the current of a PT neutral point, and sending a control signal to the vacuum contactor when detecting that the current is abnormal, so that the resonance eliminator is put into use.

Description

Technical Field

[0001] The invention relates to a short-circuiting device for testing a harmonic elimination device of a PT capacitor current of an uninterrupted power supply bus, belonging to the technical field of power grid bus testing. Background Art

[0002] Most 6-66kV distribution networks adopt the neutral point ungrounded operation mode. This operation mode greatly improves the power supply reliability of the system because it allows short-term operation with faults when single-phase grounding. However, with the expansion of urban and rural power grids and the increase in cable outlets, the system's ground capacitance current increases sharply. After single-phase grounding, the current flowing through the fault point is large, the arc is not easy to extinguish, and intermittent arc grounding overvoltage is easily generated. At the same time, since the electromagnetic voltage transformer core is saturated, it is easy to cause resonant overvoltage, resulting in a significant increase in the accident tripping rate. It is necessary to test the system capacitance current regularly. The traditional bus PT capacitance current test requires the simultaneous cooperation of dispatching, operation and maintenance, and repeated power outage operations of the bus PT, which is time-consuming and laborious. The development of a short-circuiting device for testing the harmonic elimination of the bus PT capacitance current without power outage can improve the efficiency of the bus PT capacitance current test, optimize the test link, and provide a non-stop operation mode for subsequent operations.

[0003] The existing traditional testing technology workflow is:

[0004] 1) PT power outage;

[0005] 2) Short-circuit the detuning device;

[0006] 3) PT power transmission;

[0007] 4) Capacitance current test;

[0008] 5) PT power outage;

[0009] 6) Cancel the short connection of the detuning device;

[0010] 7) PT power transmission;

[0011] This traditional testing technology workflow requires the simultaneous collaboration of dispatching, operation and maintenance, and repeated power outages of the bus PT, which is time-consuming and labor-intensive. Summary of the invention

[0012] In order to solve the above problems existing in the prior art, the present invention proposes a short-circuiting device for testing the harmonic elimination of the capacitor current of a busbar PT without power outage.

[0013] The technical solution of the present invention is as follows:

[0014] A non-stop bus PT capacitor current test harmonic elimination short-circuit device, comprising:

[0015] Built-in short-circuit module and PT neutral point current monitoring protection module;

[0016] The embedded short-circuit module includes a vacuum contactor and a control panel. The vacuum contactor is short-circuited with the detuning device of the PT capacitor current test. The control panel is used to control the opening and closing of the vacuum contactor. The opening and closing of the vacuum contactor is used to control the switching of the detuning device.

[0017] The PT neutral point current monitoring and protection module is used to detect the current of the PT neutral point, and when an abnormal current is detected, a control signal is sent to the vacuum contactor to put the harmonic eliminator into use.

[0018] As a preferred implementation, the control panel is arranged on a switch cabinet panel.

[0019] As a preferred embodiment, a plurality of indicator lights are provided on the control panel, including a closing indicator light, an opening indicator light and a protection action indicator light.

[0020] As a preferred embodiment, a button is provided on the control panel, and the button is connected to the vacuum contactor and is used to control the opening and closing of the vacuum contactor.

[0021] As a preferred implementation, the PT neutral point current monitoring and protection module includes a current transformer and a protection unit, the current transformer is used to detect current, and the protection unit sends a control signal to the vacuum contactor.

[0022] Additional aspects and advantages of the present invention will be set forth in the following description, and some of them will be apparent from the description, or may be understood by practicing the present invention. In addition, the various aspects and advantages of the present invention may be realized and obtained by the method steps and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a device module in an embodiment of the present invention;

[0024] Figure 2 It is a schematic diagram of wiring of some circuits in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of a control panel in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0028] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0029] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0030] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0031] See also Figure 1 This embodiment provides a non-stop bus PT capacitor current test detuning short-circuiting device, including:

[0032] Built-in short-circuit module and PT neutral point current monitoring protection module;

[0033] The embedded short-circuit module includes a vacuum contactor and a control panel. The vacuum contactor is short-circuited with the harmonic eliminator of the PT capacitor current test. The control panel is used to control the opening and closing of the vacuum contactor; the opening and closing of the vacuum contactor is used to control the switching of the harmonic eliminator; the opening time of the vacuum contactor is ≤20mS and the closing time is ≤30mS, thereby controlling the switching of the harmonic eliminator.

[0034] The PT neutral point current monitoring and protection module is used to detect the current of the PT neutral point, and when an abnormal current is detected, a control signal is sent to the vacuum contactor to put the harmonic eliminator into use.

[0035] As a preferred implementation of this embodiment, the control panel is arranged on the switch cabinet panel.

[0036] See also Figure 3 As a preferred implementation of this embodiment, the control panel is provided with a plurality of indicator lights, including a closing indicator light, an opening indicator light and a protection action indicator light. Through the indicator lights, the control panel can display the actual closing and opening status of the short-circuit module.

[0037] As a preferred implementation manner of this embodiment, a button is provided on the control panel, and the button is connected to the vacuum contactor and is used to control the opening and closing of the vacuum contactor.

[0038] As a preferred implementation of this embodiment, the PT neutral point current monitoring protection module includes a current transformer and a protection unit. The current transformer is used to detect current, and the protection unit sends a control signal to the vacuum contactor. The current transformer has a current input range of 1-100A and an output signal of 0-100mA, which can monitor the neutral point current. When it is found that the current has a tendency to increase resonance, the protection module will act for less than 20ms, and the vacuum contactor will control the restoration of the detuning device to prevent temporary resonance.

[0039] For details on the main circuit wiring, see Figure 2 , Figure 2 In the figure, PT is the bus voltage transformer, KM is the vacuum contactor, and CT is the current transformer (including protection unit).

[0040] Based on this embodiment, the resonator can be switched on and off without power outage, which can improve the efficiency of bus PT capacitance current testing, optimize the testing process, and provide a non-stop operation mode for subsequent operations.

[0041] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A non-stop bus PT capacitor current test harmonic elimination short-circuit device, characterized in that: include: Built-in short-circuit module and PT neutral point current monitoring protection module; The embedded short-circuit module includes a vacuum contactor and a control panel. The vacuum contactor is short-circuited with the detuning device of the PT capacitor current test. The control panel is used to control the opening and closing of the vacuum contactor. The opening and closing of the vacuum contactor is used to control the switching of the detuning device. The PT neutral point current monitoring and protection module is used to detect the current of the PT neutral point, and when an abnormal current is detected, a control signal is sent to the vacuum contactor to put the harmonic eliminator into use.

2. The non-stop bus PT capacitor current test harmonic elimination short-circuit device according to claim 1, characterized in that: The control panel is arranged on the switch cabinet panel.

3. The non-stop bus PT capacitor current test harmonic elimination short-circuit device according to claim 1, characterized in that: The control panel is provided with a plurality of indicator lights, including a closing indicator light, an opening indicator light and a protection action indicator light.

4. The non-stop bus PT capacitor current test harmonic elimination short-circuit device according to claim 1, characterized in that: The control panel is provided with buttons, which are connected to the vacuum contactor and are used to control the opening and closing of the vacuum contactor.

5. The non-stop bus PT capacitor current test harmonic elimination short-circuit device according to claim 1, characterized in that: The PT neutral point current monitoring and protection module comprises a current transformer and a protection unit, wherein the current transformer is used to detect current, and the protection unit sends a control signal to the vacuum contactor.

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