Low-voltage line emergency power supply non-inductive access system

Abstract

The invention relates to a low-voltage line emergency power supply non-inductive access system, which comprises a Rogowski coil sensor I, a Rogowski coil sensor II, an emergency power supply switching switch QF2, an emergency power supply non-inductive access auxiliary device, a puncture type wire clamp with an insulating handle and an overhead conductor, on the load side of a low-voltage line, a puncturing type wire clamp with an insulating handle directly penetrates through a wire insulating layer, and an overhead wire, an emergency power supply switching switch QF2 and an emergency power supply are electrically connected to establish a temporary conductive channel; the central processing unit compares whether the phase sequence, phase, voltage and frequency of the power grid main line are matched with those of the emergency power supply, if yes, the central processing unit outputs a signal to control an emergency power supply on / off switch QF2 to be switched on through a remote control output module, so that the emergency power supply supplies power to the load side of the low-voltage line; an emergency power supply grid-connected loop is formed on the premise of not interrupting power supply of a main line of a power grid, zero-power-failure access of the emergency power supply is achieved, access is rapid and convenient, and reliability is high.

Description

Technical Field

[0001] The present invention relates to a low-voltage line emergency power supply non-sensing access system. Background Art

[0002] As people yearn for a better life, the demand for distribution network power supply reliability is increasing. When the distribution equipment at the distribution transformer station requires routine maintenance and overhaul, the entire system, from the load side of the transformer's high-voltage switch to the load side of the low-voltage branch switch, must be switched to maintenance mode. Conventional busbar extension quick-connects within the distribution box, which allow emergency power to connect to the low-voltage line to maintain power, cannot meet these maintenance requirements. To maintain power supply to the line below the low-voltage branch switch, the current method is to first disconnect the low-voltage main switch and branch switch at the distribution transformer station. While the low-voltage line is in maintenance mode, the insulation of the low-voltage line is stripped, and the cable is connected to the emergency power supply using wire clamps. The system then switches from maintenance to operation. This results in two power outages for customers (disassembly and installation), each lasting an average of approximately 45 minutes. If the wires exiting the distribution box conduit are not color-coded to indicate phase sequence, further time is required to verify the phase sequence before successfully connecting to the backup power supply. In this case, there is an urgent need for a simple auxiliary operation and non-sensing access device that complies with operating specifications to ensure power supply to the branch lines of the distribution transformer station, thereby improving the reliability of power supply and meeting people's demand for high-quality power supply. Summary of the Invention

[0003] The purpose of the present invention is to provide a low-voltage line emergency power supply non-sensing access system to solve the technical problems in the prior art that when the distribution equipment part of the distribution transformer area needs normal maintenance and overhaul, the emergency power supply is connected to the low-voltage line to ensure power supply, and the electricity users will experience two power outages (disassembly and installation), with an average power outage time of about 45 minutes each time, and the phase sequence needs to be checked before the backup power supply can be successfully connected, which is cumbersome to operate, takes a long time to operate, and has low reliability.

[0004] The present invention is achieved through the following technical solutions:

[0005] A low-voltage line emergency power supply non-inductive access system, characterized by comprising: a Rogowski coil sensor 1, a Rogowski coil sensor 2, an emergency power supply on / off switch QF2, an emergency power supply non-inductive access auxiliary device, a piercing type wire clamp with an insulated handle, and an overhead conductor, wherein:

[0006] On the load side of the low-voltage line, a piercing wire clamp with an insulating handle is used to directly penetrate the insulation layer of the conductor, and a temporary conductive path is established by connecting the overhead conductor and the emergency power supply on / off switch QF2 to the emergency power supply.

[0007] The emergency power supply sensorless access auxiliary device includes an AC sampling module, a central processing unit, a voltage and frequency sampling module, and a remote control output module. Rogowski coil sensor 1 is installed on the load side of the low-voltage line to detect the phase sequence and phase signal of the main power supply of the power grid, and transmits it to the central processing unit through the AC sampling module. Rogowski coil sensor 2 is installed on the side of the emergency power supply to detect the phase sequence and phase signal of the emergency power supply, and transmits it to the central processing unit through the AC sampling module. The voltage and frequency signals of the main power supply line and the voltage and frequency signals of the emergency power supply are respectively extracted at points A and B on both sides of the emergency power supply on / off switch QF2, and are transmitted to the central processing unit through the voltage and frequency sampling module. The central processing unit compares the phase sequence, phase, voltage, and frequency of the main power supply line and the emergency power supply to see if they match. If they match, the central processing unit outputs a signal to control the emergency power supply on / off switch QF2 to close, so that the emergency power supply supplies power to the load side of the low-voltage line, forming an emergency power supply grid-connected loop without interrupting the power supply of the main power grid.

[0008] Preferably, the central processing unit adopts a single-chip microcomputer MCU, the emergency power on / off switch QF2 is a relay switch with a wireless receiving module, and the remote control output module is a wireless transmitting module. The signal sent by the remote control output module is received by the wireless receiving module to control the emergency power on / off switch QF2.

[0009] Preferably, a switch QF1 is further provided at the output end of the emergency power supply.

[0010] Preferably, the emergency power supply non-sensing access auxiliary device further includes a display and alarm module, and the central processing unit outputs signals to the display and alarm module.

[0011] Preferably, the emergency power supply non-sensing access auxiliary device further includes a power module, which provides low-voltage direct current.

[0012] Preferably, the display and alarm module includes an indicator light circuit, a screen display circuit and a voice alarm circuit.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] Effect 1: Senseless switching, using live puncture access technology, achieves "zero power outage" access to emergency power supply, eliminating the two short power outages in traditional operations;

[0015] Effect 2: Safe and reliable, the main channel circuit breaker switch has an arc extinguishing chamber function;

[0016] Effect 3: Rapid deployment, puncture clamp operation time is less than 3 minutes, and the entire process can be completed within 10 minutes (traditional method takes 45 minutes);

[0017] Effect 4: The emergency power supply non-sensing access auxiliary device is an intelligent monitoring and control system that integrates all-round detection of the phase sequence, voltage, frequency, and phase of the generator and the power grid, providing an effective and reliable basis for the adjustment of generator parameters and simplifying the emergency power supply access process.

[0018] Effect 5: Modular design, adopts quick-plug interface (IP67 protection level), supports 400A continuous current carrying capacity, and is compatible with mainstream power generation vehicle interfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other purposes, features and advantages of the present invention will become more apparent by describing in more detail the preferred embodiments of the present invention shown in the accompanying drawings. The same reference numerals indicate the same parts throughout the accompanying drawings, and the drawings are not intentionally scaled to actual size, but rather are intended to illustrate the subject matter of the present invention.

[0020] Figure 1 An electrical schematic diagram of the wiring of the present invention;

[0021] Figure 2 A circuit block diagram of the present invention;

[0022] Figure 3 This is a control principle diagram of the emergency power on / off switch of the present invention. DETAILED DESCRIPTION

[0023] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings.

[0024] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element and integrated therewith, or there may be an intermediate element. The terms "mounted", "one end", "the other end" and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] refer to Figure 1 、 Figure 2 and Figure 3 As shown, an embodiment of the present invention provides a low-voltage line emergency power supply non-inductive access system, including a Rogowski coil sensor 1, a Rogowski coil sensor 2, an emergency power supply on / off switch QF2, an emergency power supply non-inductive access auxiliary device, a piercing type wire clamp with an insulated handle, and an overhead conductor, wherein:

[0027] On the load side of the low-voltage line, a piercing wire clamp with an insulating handle is used to directly penetrate the insulation layer of the conductor, and a temporary conductive path is established by connecting the overhead conductor and the emergency power supply on / off switch QF2 to the emergency power supply.

[0028] The emergency power supply sensorless access auxiliary device includes an AC sampling module, a central processing unit, a voltage and frequency sampling module, and a remote control output module. Rogowski coil sensor 1 is installed on the load side of the low-voltage line to detect the phase sequence and phase signal of the main power supply of the power grid, and transmits it to the central processing unit through the AC sampling module. Rogowski coil sensor 2 is installed on the side of the emergency power supply to detect the phase sequence and phase signal of the emergency power supply, and transmits it to the central processing unit through the AC sampling module. The voltage and frequency signals of the main power supply line and the voltage and frequency signals of the emergency power supply are respectively extracted at points A and B on both sides of the emergency power supply on / off switch QF2, and are transmitted to the central processing unit through the voltage and frequency sampling module. The central processing unit compares the phase sequence, phase, voltage, and frequency of the main power supply line and the emergency power supply to see if they match. If they match, the central processing unit outputs a signal to control the emergency power supply on / off switch QF2 to close, so that the emergency power supply supplies power to the load side of the low-voltage line, forming an emergency power supply grid-connected loop without interrupting the power supply of the main power grid.

[0029] Preferably, the central processing unit adopts a single-chip microcomputer MCU, and the emergency power supply on / off switch QF2 is a relay switch with a wireless receiving module. The relay switch control is introduced in textbooks or related patents through wireless control. It is a common technology and will not be described here. The remote control output module is a wireless transmitting module. The signal emitted by the remote control output module is received by the wireless receiving module to control the emergency power supply on / off switch QF2.

[0030] Preferably, a switch QF1 is further provided at the output end of the emergency power supply.

[0031] Preferably, the emergency power supply non-sensing access auxiliary device further includes a display and alarm module, and the central processing unit outputs signals to the display and alarm module.

[0032] Preferably, the emergency power supply non-sensing access auxiliary device further includes a power module, which provides low-voltage direct current.

[0033] Preferably, the display and alarm module includes an indicator light circuit, a screen display circuit and a voice alarm circuit.

[0034] Preferably, the emergency power supply adopts an emergency power supply vehicle with frequency modulation function

[0035] Notice: Figure 1On the load side of medium and low voltage lines, piercing wire clamps with insulated handles are used to directly penetrate the insulation layer of the conductor. The figure only shows a single line, but it is actually a 3-phase 4-wire system (that is, it has 4 wires, including the ground wire). In order to simplify the drawing, only one wire is drawn.

[0036] Figure 1 In the example, the electricity user of the 4011 switch on the load side of the low-voltage line is used as an example to quickly access the low-voltage line emergency power supply senseless access system of the present invention. The specific operations are as follows:

[0037] 1. Access system:

[0038] (1) Press Figure 1 The diagram shows the connections for an emergency power supply with automatic adaptation function, an emergency power supply non-inductive access auxiliary device, a piercing wire clamp with an insulated handle, and an overhead conductor.

[0039] (2) Start the generator car and manually close the emergency power supply switch QF1. The emergency power supply is connected to the auxiliary device self-test module without induction to perform a matching test on the main power supply (i.e., the main line power supply of the power grid) and the emergency power supply.

[0040] (3) If the match is successful, the emergency power supply on / off switch QF2 will automatically close and the system will be connected to the grid once.

[0041] (4) If the circuit breaker cannot be closed, use a piercing type wire clamp with an insulated handle to adjust the phase sequence of the grid-connected emergency power supply;

[0042] (5) Disconnect the branch 4011 switch of the main power supply and remove the jumper wire on the #1 utility pole;

[0043] (6) The line equipment on the main power supply side of the #1 utility pole can be transferred to maintenance status.

[0044] 2. Exit the system:

[0045] (1) Switch the main power supply branch 4011 to hot standby mode and connect the jumper wire of pole #1;

[0046] (2) Manually close the branch switch 4011 of the main power supply, and the emergency power supply is connected to the auxiliary device self-test module to perform matching detection on the main and backup power supplies.

[0047] (3) The matching is successful, the emergency power supply on / off switch QF2 continues to be in the closed state, and the secondary power supply is connected to the grid;

[0048] (4) If the matching fails, the emergency power supply on / off switch QF2 will automatically trip the emergency power supply;

[0049] (5) Manually disconnect the emergency power switch QF1 and remove all emergency power cables and equipment.

[0050] The present invention has the following advantages: Effect 1: Non-sensing switching, using live puncture access technology to achieve "zero power outage" access to the emergency power supply, eliminating the two short power outages of traditional operations; Effect 2: Safe and reliable, the main channel circuit breaker switch has an arc extinguishing chamber function; Effect 3: Rapid deployment, the puncture clamp operation time is less than 3 minutes, and the entire process operation can be completed within 10 minutes (the traditional method takes 45 minutes); Effect 4: The emergency power supply non-sensing access auxiliary device is an intelligent monitoring and control system that integrates all-round detection of the phase sequence, voltage, frequency, and phase of the generator and the power grid, providing an effective and reliable basis for generator parameter adjustment and simplifying the emergency power supply access process. Effect 5: Modular design, using a quick-plug interface (IP67 protection level), supports 400A continuous current carrying capacity, and is compatible with mainstream power generation vehicle interfaces.

[0051] Working Principle of the Invention: This device is based on the principle of "intelligent bypass and non-sensing switching" technology, and uses a combination of live working and intelligent detection and control to achieve seamless access to emergency power. On the load side of the low-voltage line #1 pole (jumper port), a piercing wire clamp with an insulated handle directly penetrates the conductor insulation to establish a temporary conductive path, forming an emergency power grid-connected circuit without interrupting the main power supply line. 1. Before grid connection, the following synchronization conditions must be met:

[0052] (1) Phase sequence consistency: The phase sequence of the generator (i.e. emergency power supply) and the power grid must be exactly the same.

[0053] (2) Voltage matching: The difference between the generator output voltage and the grid voltage amplitude must be within ±5%.

[0054] (3) Frequency synchronization: The difference between the generator frequency and the grid frequency must be within ±0.1Hz.

[0055] (4) Phase angle consistency: The phase angles of the generator voltage waveform and the grid voltage waveform must be aligned.

[0056] 2. Centrally use Rogowski coil to automatically check phase sequence and phase

[0057] Two independent Rogowski coils are used, namely Rogowski coil sensor 1 and Rogowski coil sensor 2, respectively, which are positioned at the two points where phase verification is required. Each Rogowski coil sensor inputs the processed current signal (containing amplitude and phase information) into the "central processing unit" or directly transmits the data to a handheld display terminal via wireless or wired means. The central processing unit performs phase difference calculations internally: it calculates the phase angle difference "ΔΦ" between the corresponding phases of points A and B (usually AA, BB, CC). Automatic judgment: Based on a preset threshold (usually close to 0°, such as ±10° or less), the device automatically determines whether the phases are consistent (in phase) or there is a phase difference, and provides the result through indicator lights (red / green), screen displays (angle value, in-phase / out-of-phase prompts), and audible alarms.

[0058] 3. Use incandescent lamps (commonly known as light bulbs) to determine whether the generator frequency is synchronized with the grid frequency

[0059] (1) Voltage difference and phase difference: When the frequencies (fg and fn) of the generator voltage (Ug) and the grid voltage (Un) are not exactly the same, the phase difference (δ) between them will continue to change (dδ / dt = 2π(fg-fn)).

[0060] (2) Across-voltage: Connect an incandescent lamp between the generator output and the corresponding phase terminal of the grid (i.e., across the switch to be connected). In this way, the voltage across the lamp is the difference between the instantaneous values ​​of the generator voltage and the grid voltage (`ΔU = Ug - Un`).

[0061] (3) Brightness variation: The magnitude and direction of ΔU changes periodically with the phase difference δ. When δ = 0° (in phase), ΔU ≈ 0 (ideal, ignoring voltage amplitude differences), and the bulb is dimmest or off. When δ = 180° (out of phase), ΔU is maximum (approximately 2Ug or 2Un), and the bulb is brightest.

[0062] (4) Frequency difference and flicker frequency: The frequency at which the bulb changes brightness (f_flash) is equal to the absolute value of the difference between the generator frequency and the grid frequency: f_flash = |fg-fn|. If fg = fn, the phase difference δ is constant (assuming the voltage amplitude is also equal), then ΔU is a constant value, and the bulb maintains "constant brightness" (usually not completely off, unless Ug is strictly equal to Un and the phase is exactly the same). If fg ≠ fn, the brightness of the bulb will flicker periodically. The speed of the flicker directly reflects the magnitude of the frequency difference. The faster the flicker, the greater the frequency difference; the slower the flicker, the smaller the frequency difference.

[0063] After the central processing unit receives and processes this data and determines that the main and emergency power supply parameters match and meet grid-connected operation conditions, the system's emergency power on / off switch QF2, under the control of the intelligent control system, automatically connects the emergency power supply to the grid for parallel operation. The distribution transformer and related equipment can then be shut down for maintenance, ensuring uninterrupted load current transfer and thus providing uninterrupted power to users.

[0064] The above embodiments merely represent specific implementation methods of the invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be based on the appended claims.

Claims

1. A low-voltage line emergency power supply non-sensing access system, characterized by: It includes Rogowski coil sensor 1, Rogowski coil sensor 2, emergency power on / off switch QF2, emergency power non-inductive access auxiliary device, piercing type wire clamp with insulated handle and overhead wire, among which: On the load side of the low-voltage line, a piercing wire clamp with an insulating handle is used to directly penetrate the insulation layer of the conductor, and a temporary conductive path is established by connecting the overhead conductor and the emergency power supply on / off switch QF2 to the emergency power supply. The emergency power supply sensorless access auxiliary device includes an AC sampling module, a central processing unit, a voltage and frequency sampling module, and a remote control output module. Rogowski coil sensor 1 is installed on the load side of the low-voltage line to detect the phase sequence and phase signal of the main power supply of the power grid, and transmits it to the central processing unit through the AC sampling module. Rogowski coil sensor 2 is installed on the side of the emergency power supply to detect the phase sequence and phase signal of the emergency power supply, and transmits it to the central processing unit through the AC sampling module. The voltage and frequency signals of the main power supply line and the voltage and frequency signals of the emergency power supply are respectively extracted at points A and B on both sides of the emergency power supply on / off switch QF2, and are transmitted to the central processing unit through the voltage and frequency sampling module. The central processing unit compares the phase sequence, phase, voltage, and frequency of the main power supply line and the emergency power supply to see if they match. If they match, the central processing unit outputs a signal to control the emergency power supply on / off switch QF2 to close, so that the emergency power supply supplies power to the load side of the low-voltage line, forming an emergency power supply grid-connected loop without interrupting the power supply of the main power grid.

2. A low-voltage line emergency power supply non-sensing access system as claimed in claim 1, characterized in that: The central processing unit adopts a single-chip microcomputer MCU, the emergency power on / off switch QF2 is a relay switch with a wireless receiving module, and the remote control output module is a wireless transmitting module. The signal sent by the remote control output module is received by the wireless receiving module to control the emergency power on / off switch QF2.

3. A low-voltage line emergency power supply non-sensing access system as claimed in claim 2, characterized in that: The output end of the emergency power supply is also provided with a switch QF1.

4. A low-voltage line emergency power supply non-sensing access system according to any one of claims 1 to 3, characterized in that: The emergency power supply non-sensing access auxiliary device also includes a display and alarm module, and the central processing unit outputs signals to the display and alarm module.

5. A low-voltage line emergency power supply non-sensing access system as claimed in claim 4, characterized in that: The emergency power supply non-sensing access auxiliary device also includes a power module, which provides low-voltage direct current.

6. A low-voltage line emergency power supply non-sensing access system according to any one of claim 4, characterized in that: The display and alarm module includes an indicator light circuit, a screen display circuit and a voice alarm circuit.

7. A low-voltage line emergency power supply non-sensing access system according to any one of claim 4, characterized in that: The emergency power supply uses an emergency power supply vehicle with frequency modulation function.

Images