Passive filtering compensation device

Abstract

The utility model discloses a passive filtering compensation device. Comprising a circuit breaker, an isolating switch, an adjustable reactor, a change-over switch device, a lightning arrester, a capacitor bank, a discharge coil and a controller, wherein the adjustable reactor is provided with a plurality of inductance taps; the change-over switch device is provided with a multi-path on-off switch which is correspondingly connected with a plurality of inductance taps; the adjustable reactor is connected with one end of the capacitor bank through the inductance tap and the change-over switch device; the other end of the capacitor bank is connected with a load; the discharge coil is connected in parallel with the capacitor bank; a trigger plate is arranged in the change-over switch device, and the controller is in control connection with an on-off switch in the change-over switch device through the trigger plate. The device is simple and reasonable in structure, the inductance value of the reactor can be conveniently adjusted on line, adjustment can be carried out without power failure, the working efficiency can be improved, and the cost and time are saved.

Description

Technical Field

[0001] The utility model belongs to the technical field of passive filtering, in particular to a passive filtering compensation device. Background Art

[0002] The nonlinear loads in the steel, petroleum, chemical, coal, printing and dyeing industries generate a large amount of harmonics during operation, and the power factor is low, which will pollute the power supply system and affect the power supply quality. The passive filter compensation device is used to form a single tuned or high-pass filter channel, which has a good filtering effect on harmonics, and at the same time, it performs reactive power compensation on the system, improves the power factor of the system, improves the stability of the system voltage, and ensures the safety and reliability of the power supply system.

[0003] The inductance of the reactor of the traditional passive filter compensation device cannot be adjusted or the inductance value of the reactor cannot be adjusted by manually connecting different inductance taps; usually, the inductance taps of the reactor are adjusted manually after the equipment is powered off to achieve better harmonic filtering; however, the grid load is generally operated uninterruptedly, and the passive filter compensation device currently using manual adjustment has the following disadvantages: power outage is required for adjustment, serious time waste, low manual adjustment efficiency and high cost, etc. Utility Model Content

[0004] In order to solve the deficiencies in the prior art, the utility model provides a passive filtering compensation device that solves at least some of the above-mentioned technical problems. The device has a simple and reliable structure, is easy to adjust the inductance value of the reactor online, and does not require power outage for manual adjustment, which helps to improve work efficiency and save costs and time.

[0005] To achieve the above object, the utility model provides a passive filtering compensation device, which includes: a circuit breaker, an adjustable reactor, a switching device, a capacitor bank, a discharge coil and a controller, wherein:

[0006] One end of the circuit breaker is connected to the high-voltage bus, and the other end is connected to the adjustable reactor; the adjustable reactor is provided with a plurality of inductance taps; the switching switch device has a multi-way splitter connected to the plurality of inductance taps; the adjustable reactor is connected to one end of the capacitor bank through the switching switch device; the other end of the capacitor bank is connected to the load; the discharge coil is connected in parallel with the capacitor bank; a trigger board is provided in the switching switch device, and the controller is controlled to be connected to the splitter and splitter in the switching switch device through the trigger board.

[0007] In an optional embodiment, the circuit breaker is a sulfur hexafluoride circuit breaker.

[0008] In an optional implementation, the adjustable reactor is provided with 5 inductance taps.

[0009] In an optional embodiment, the on-off switch in the switching switch device adopts an on-off switch with a voltage level of 1.5KV.

[0010] In an optional embodiment, the device further comprises: an isolating switch, wherein the isolating switch is arranged to be connected between the circuit breaker and the adjustable reactor.

[0011] In an optional embodiment, the device further comprises: a lightning arrester, wherein the lightning arrester is arranged and connected between the switching device and the capacitor bank.

[0012] Compared with the prior art, the beneficial effects of the present invention include at least:

[0013] 1. The utility model provides a passive filtering compensation device with a simple and reasonable structure and high reliability. By adding a connection switching switch device to the inductance tap of the adjustable reactor, it is convenient to adjust the inductance value of the reactor online without power outage, thereby improving work efficiency and saving cost and time.

[0014] 2. The passive filtering compensation device provided by the utility model helps to improve the filtering effect and grid stability and increase the service life of the equipment.

[0015] Other features and advantages of the utility model will be described in the following description, and partly become apparent from the description, or understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures particularly pointed out in the written description and the drawings.

[0016] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention.

[0019] Figure 1 A schematic structural diagram of a passive filtering compensation device provided in an embodiment of the utility model.

[0020] Figure 2A schematic diagram of the functional structure of a controller provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0021] In order to make the technical means, creative features, objectives and effects of the utility model easy to understand, the utility model is further described below in conjunction with specific implementation methods. The embodiments described in this application are only part of the embodiments of the utility model, not all of them. Based on the spirit of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] At present, the inductance adjustment of the reactor of a general passive filter compensation device is usually manually selected by the staff to connect the appropriate inductance tap. This process requires detection and application for equipment power outage based on the detection results. Since the equipment has a capacitor energy storage element, the equipment needs to have sufficient discharge time after the power outage. However, whether the requirements are met after adjustment needs to be detected again. This process needs to be repeated many times. At this time, the load has been in operation, which will cause harmonics to escape to the power grid and cause serious harm to the power grid. At the same time, the above operation process will bring a lot of manpower waste and increase the detection cost. In addition, the inductance tap of the reactor of the general passive filter compensation device is adjusted once every few weeks or months. At this time, the grid impedance and system load may have changed. Moreover, most of the loads are nonlinear and change every minute. The equipment impedance resonance point cannot be dynamically adjusted according to these changes, which will lead to poor filtering effect of the passive filter compensation device and affect the quality of the power grid.

[0024] To solve the above problems, see Figure 1 and Figure 2 As shown, the embodiment of the utility model provides a passive filtering compensation device, which mainly includes: a circuit breaker, an adjustable reactor, a switching device, a capacitor bank, a discharge coil and a controller, wherein:

[0025] One end of the circuit breaker is connected to the high-voltage busbar, and the other end is connected to the adjustable reactor; the adjustable reactor is provided with a plurality of inductance taps; the switching device has a multi-way splitter and closeer connected to the plurality of inductance taps; the adjustable reactor is connected to one end of the capacitor bank through the inductance tap and the switching device; the other end of the capacitor bank is connected to the load; the discharge coil is connected in parallel with the capacitor bank; a trigger board is provided in the switching device, and the controller is connected to the splitter and closeer control in the switching device through the trigger board.

[0026] The specific implementation mode and working principle of the utility model device are described in detail below:

[0027] In a specific embodiment, the circuit breaker plays the role of switching on and off the passive filtering compensation device. Since the passive filtering compensation device needs to cut off the capacitive current, the breaking process will produce voltage and current transient phenomena, which may cause serious problems after heavy breakdown. Therefore, in this embodiment, a sulfur hexafluoride circuit breaker with strong breaking and arc extinguishing capabilities is used to cut off the capacitive current of the passive filtering compensation device, greatly reducing the voltage and current transient phenomena generated during the breaking process, and avoiding serious problems that may occur after heavy breakdown. In this example, the LW8-40.5 (T) type sulfur hexafluoride circuit breaker is preferably selected. This type of sulfur hexafluoride circuit breaker has a rated voltage of 40.5kV and a current carrying capacity of 630A; it has a built-in current transformer, which can detect the current of the device. The current transformer outputs two current signals, which are sent to the controller or the background for current detection and protection. In this embodiment, the current transformer range is 125A / 5A.

[0028] In this embodiment, a plurality of inductance taps may be provided on the adjustable reactor for correspondingly adjusting different inductance values ​​of the adjustable reactor; specifically, 5 inductance taps may be provided, corresponding to inductance value adjustments of +5%, +2.5%, 0%, -2.5% and -5%, respectively; the non-blocking adjustment facilitates the passive filtering compensation device to be adjusted according to its own resonance point and grid changes, thereby improving the harmonic filtering effect.

[0029] Furthermore, the switching switch device has 5-way on-off switches corresponding to the 5 inductance taps. The switch model selected in this embodiment is: CKJP-200 / 1.5-D type electric on-off vacuum bypass switch, rated on-off current 200A, voltage 1.5kV; the switching can be completed within 10ms to complete the inductance adjustment of the reactor, so as to achieve real-time adjustment of the impedance of the passive filtering compensation device, improve the filtering effect of the device, reduce the harmonics flowing into the device when the equipment is overloaded, and increase the service life of the product. In this embodiment, a trigger board is provided in the switching switch device, and the trigger board is powered by a 220V isolation transformer; the controller is connected to the on-off switch control in the switching switch device through the trigger board, and the trigger board receives the on-off command of the controller to issue the on-off command to the corresponding switch, and sends the status of the switch after switching; the controller can be set on-site, and can also be preferably set in a monitoring center or control center, so it is not in the Figure 1 As shown in the figure, the controller preferably communicates with the trigger board through optical fiber. The controller adopts 24V DC power supply and has a 485 communication interface with high reliability. In specific operation, the controller collects the current flowing into the device, compares it with the set value to obtain the inductance tap that needs to be switched, and transmits instructions through the trigger board to control and adjust the opening and closing state of the corresponding opening and closing switch in the switching device, so as to realize automatic switching of different inductance taps.

[0030] In a specific embodiment, see Figure 1 As shown, the device preferably also includes: an isolating switch, which is set and connected between the circuit breaker and the adjustable reactor. The isolating switch is mainly used to ensure that the equipment maintenance process and the power grid have an observable physical breakpoint to ensure safety when operating the equipment. The isolating switch model in this embodiment is GW4-40.5DW / 630A.

[0031] In a specific embodiment, see Figure 1 As shown, the device preferably also includes: a lightning arrester, one end of which is connected to the output end of the switching device and the capacitor bank respectively, and the other end of the lightning arrester is grounded. The model of the lightning arrester selected in this embodiment is: YH5WR-51 / 134-500. The main function of the lightning arrester is to quickly discharge the voltage when there is an operating overvoltage or a lightning overvoltage, clamp the device to a safe voltage range, and protect the device.

[0032] In a specific embodiment, see Figure 1As shown, the capacitor bank of the device preferably includes: multiple groups of capacitor banks (two groups are set considering the cost), the capacitor model in this embodiment is: AAM / 79-13-400-1W, the rated voltage of a single capacitor is 13kV and the capacity is 400kvar, two series and two parallel, the purpose of increasing the voltage of the capacitor bank is achieved by connecting a single capacitor in series, and the ability of the equipment to output reactive power and filter harmonics is improved by connecting a single capacitor in parallel. The corresponding discharge coil includes two groups of discharge coils; the electric coil is connected in parallel with the capacitor bank; the function of the discharge coil is to discharge the residual voltage of the capacitor bank through the discharge coil after the equipment is exited, so that the residual energy of the capacitor bank can be quickly discharged to a safe range; the discharge coil model selected in this embodiment is: FDEC-13+13-10.0-1W.

[0033] In a specific embodiment, the passive filtering compensation device can be a branch or a combination of multiple branches according to the load harmonic characteristics. Figure 2 Taking a three-phase branch ABC as an example (each phase has five inductance taps, and one inductance tap is connected to a corresponding opening and closing switch), the working principle of the device is explained:

[0034] When the passive filter compensation device is working, the controller obtains the current flowing into the device and compares it with the fixed value set by the controller: when the corresponding whole frequency current and high-order harmonics flowing into the device are lower than the installed capacity range of the device, the controller calculates the appropriate resonance point of the device through the input capacitor group parameters and the corresponding inductance values ​​of different taps of the reactor. The controller transmits the closing and opening instructions to the trigger board through the TX optical fiber to trigger a certain opening and closing switch in the switching switch device, and cuts the corresponding inductance tap; through the above operation, the impedance of the adjustable reactor of the device is reduced, the inflow harmonic current increases, and the filtering effect is improved. In specific implementation, in order to prevent the switching switch from arcing when disconnecting, the controller will first close a certain tap opening and closing switch, the trigger board detects the closing position and transmits it to the controller through the RX optical fiber, and the controller then issues a gate opening instruction to the previously running opening and closing switch, the trigger board detects that the closing position of the opening and closing switch disappears and transmits it to the controller through the RX optical fiber, and completes the adjustment of the reactor inductance tap, which minimizes the arcing caused by the switching switch breaking the current, and the three phases A, B, and C operate simultaneously. For 3-35kV high-voltage systems, the points on the entire reactor are lower than 4kV, and the main voltage is carried on the capacitor bank. At the same time, the tap of the reactor is adjusted according to 10% of the reactor (±5%), so the voltage difference between the taps of the reactor inductance is about 4kV*10%≈400V. In order to ensure the reliability of the switching switch, a 1.5KV fast switching switch is preferably selected in this embodiment, and the closing and opening time is within 10mS, so the entire control + closing and opening process can be completed within 30mS.

[0035] When the corresponding whole frequency current and high-order harmonics flowing into the device are larger than the installed capacity range of the device, and it is in overload or close to protection tripping, the controller calculates the appropriate resonance point of the device through the input capacitor bank parameters and the corresponding inductance values ​​of different taps of the reactor, and the controller transmits the closing and opening instructions to the trigger board through the TX optical fiber to trigger a certain opening and closing switch in the switching device, and cuts the corresponding inductance tap; through the above operation, the impedance of the adjustable reactor of the device is increased, the current flowing into the device is reduced, and the harmonic current flowing into the device is reduced, thereby solving the problems of equipment overload and tripping, heating, and insulation reduction caused by overload. In specific implementation, in order to prevent the switching switch from arcing when disconnecting, the controller will first close a certain tap opening and closing switch, the trigger board detects the closing position and transmits it to the controller through the RX optical fiber, and the controller then issues a disconnection instruction to the previously running opening and closing switch, the trigger board detects that the closing position of the opening and closing switch disappears and transmits it to the controller through the RX optical fiber, and completes the adjustment of the reactor inductance tap, which minimizes the arcing caused by the switching switch disconnecting current.

[0036] It should be noted that the purpose of the present invention is to protect the structure of the passive filtering compensation device. The working principle of the controller and the realization of the control function are prior arts known to those skilled in the art, and are not within the scope of protection of the present invention. Those skilled in the art can obtain them from the circuit diagrams and structure diagrams of the corresponding existing products, and can make adaptive connections based on the instructions of each specific model device. At the same time, the models of each component in the passive filtering compensation device are selected according to the actual application scenario. This embodiment records only the preferred settings, not specific limitations, and will not be elaborated on here.

[0037] Through the description of the above embodiments, those skilled in the art can know that the passive filtering compensation device provided by the utility model has a simple and reliable structure, and a connecting switching switch device is added to the inductance tap of the reactor to facilitate online adjustment of the inductance value of the reactor, without the need for power outage for manual adjustment, which is beneficial to improving work efficiency, saving costs and time, and improving grid stability. At the same time, it is convenient to make timely adjustments according to load conditions, reduce the frequency of equipment tripping, help improve equipment reliability, and increase equipment service life.

[0038] This specification adopts a progressive description, and the same and similar parts between various implementations can be referred to each other. The unexplained parts of the implementation methods of the utility model can be obtained from the corresponding product manual or the prior art in the field, which are well-known contents in the field and will not be repeated.

[0039] The above embodiments of the present invention are described in detail, and the principles and implementation methods of the present invention are described. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. The above description of the disclosed embodiments enables professionals and technicians in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in this field, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A passive filtering compensation device, characterized in that: The device includes: a circuit breaker, an adjustable reactor, a switching device, a capacitor bank, a discharge coil and a controller, wherein: One end of the circuit breaker is connected to the high-voltage bus, and the other end is connected to the adjustable reactor; the adjustable reactor is provided with a plurality of inductance taps; the switching switch device has a multi-way splitter connected to the plurality of inductance taps; the adjustable reactor is connected to one end of the capacitor bank through the switching switch device; the other end of the capacitor bank is connected to the load; the discharge coil is connected in parallel with the capacitor bank; a trigger board is provided in the switching switch device, and the controller is controlled to be connected to the splitter and splitter in the switching switch device through the trigger board.

2. A passive filtering compensation device according to claim 1, characterized in that: The circuit breaker is a sulfur hexafluoride circuit breaker.

3. A passive filtering compensation device according to claim 1, characterized in that: The adjustable reactor is provided with 5 inductance taps.

4. A passive filtering compensation device according to claim 1, characterized in that: The on-off switch in the switching switch device adopts an on-off switch with a voltage level of 1.5KV.

5. A passive filtering compensation device according to claim 1, characterized in that: The device also includes: an isolating switch, which is arranged and connected between the circuit breaker and the adjustable reactor.

6. A passive filtering compensation device according to claim 1, characterized in that: The device also includes: a lightning arrester, which is arranged and connected between the switching device and the capacitor group.

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