Variable step size on-load tap changer, control method, system, equipment and medium

Abstract

The invention provides a variable-step-size on-load tap changer, a control method, a control system, equipment and a medium. The variable-step-size on-load tap changer comprises at least one static contact unit, two moving contact mechanisms and a control device, wherein the two moving contact mechanisms independently slide on the static contact unit; the control device is connected with the two moving contact mechanisms; the static contact unit comprises three static contacts, and all the static contacts are arranged in an annular array. Each moving contact mechanism realizes uninterruptible conductive connection switching with each static contact in the sliding process; by means of the characteristics that the number of the static contacts is matched with that of the moving contact mechanisms, the moving contact mechanisms move independently, and all the static contacts are arranged in an annular array, the two moving contact mechanisms can slide to the static contact of any potential in one-step action, the static contacts of multiple potentials are combined and connected pairwise, seven voltage adjusting gears are formed, and the voltage adjusting efficiency is improved. Therefore, one-step switching between variable-step voltage regulation and any voltage regulation gear is realized, and cross-gear quick regulation is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrical switches, and particularly relates to a step-variable on-load tap-changer, a control method, a system, a device, and a medium. Background Art

[0002] In recent years, a large number of new energy power generations with power randomness, intermittency, and volatility, as well as new types of loads (such as industrial loads, railway traction loads, charging loads, etc.) have been connected to the power grid, resulting in rapid voltage fluctuations in the power grid lines, affecting the stability of the power system, the reliability of power equipment, and the safety of power users. In addition, in some scenarios, flexible and rapid power supply voltage regulation is required to meet the production process requirements. The above problems and requirements pose many new challenges to the flexible and rapid regulation of the power supply voltage.

[0003] Power supply voltage regulation is usually achieved by technical means such as transformer voltage regulation and reactive power compensation. The transformer voltage regulation technology can realize voltage adjustment without power interruption through multiple taps of windings in combination with on-load tap-changers, series-parallel power electronic converters, etc. Compared with the latter, the method of combining with on-load tap-changers in the former has advantages such as simplicity, reliability, and less maintenance, and is widely used in industries such as power grids, railways, industry, and commerce. However, the existing on-load tap-changers (including mechanical types, mechanical-electronic hybrid types, etc.) have slow adjustment speeds and cannot achieve flexible and free switching between gears. For example, they cannot switch directly to any gear in one step, resulting in limitations in both the response speed and the voltage adjustment step size, and it is difficult to meet the requirements for the rapid on-load voltage regulation of transformers or the development of new types of transformers in future various power supply and consumption scenarios. Summary of the Invention

[0004] To overcome the deficiencies of the above-mentioned prior art, the present invention proposes a step-variable on-load tap-changer, comprising: at least one static contact unit, two moving contact mechanisms that independently slide on the static contact unit, and a control device connected to the two moving contact mechanisms; The static contact unit includes three static contacts, and the three static contacts are correspondingly connected to the three input ends of the on-load tap-changer. All the static contacts are arranged in a circular array, and there is a spacing between two adjacent static contacts; During the sliding process of each moving contact mechanism, a non-power-interrupting conductive connection switching is achieved between each moving contact mechanism and each static contact; the moving contact mechanism is connected to the output end of the on-load tap-changer.

[0005] Preferably, each static contact has two conductive surfaces, and the two conductive surfaces of all the static contacts respectively form two circumferential surfaces, and the two moving contact mechanisms independently slide along the two circumferential surfaces.

[0006] Preferably, each of the moving contact mechanisms includes a turntable arranged coaxially with the circumferential surface, a transition current limiter electrically connected and fixed on the turntable, an adaptive non-linear voltage limiter, and a metal pole bar; One ends of the transition current limiter, the adaptive non-linear voltage limiter, and the metal pole bar are arranged in sequence along the circumferential direction of the turntable, and the other ends of the transition current limiter, the adaptive non-linear voltage limiter, and the metal pole bar are in sliding contact with the conductive surface; the distance between the transition current limiter and the metal pole bar is less than the width of the conductive surface and greater than a set electrical insulation clearance; the turntable is connected to the output end of the on-load tap-changer.

[0007] Preferably, when the voltage between the adaptive non-linear voltage limiter and the static contact in contact therewith is greater than or equal to a set voltage protection value, the impedance of the adaptive non-linear voltage limiter is less than a set lower impedance limit value; When the voltage between the adaptive non-linear voltage limiter and the static contact in contact therewith is less than the voltage protection value, the impedance of the adaptive non-linear voltage limiter is greater than a set upper impedance limit value.

[0008] Preferably, the adaptive non-linear voltage limiter includes one of the following: Zener diode, switching thyristor, varistor.

[0009] Preferably, when the number of the static contact units is two or more, the three static contacts in each static contact unit are coded in ascending order, and the multiple static contact units are coded cyclically. The static contacts with the same code in each static contact unit are connected by an interconnection bus, and after the static contacts with the same code are connected, they are correspondingly connected to the three input ends of the on-load tap-changer, and the three input ends are connected to different taps of a power supply or a transformer winding.

[0010] Preferably, controllable switches are arranged on the transition current limiter and the metal pole bar.

[0011] Preferably, the control device includes a turntable driver connected to the turntable and a controller electrically connected to the turntable driver.

[0012] Based on the same inventive concept, the present invention also provides a control method for an on-load tap-changer with variable step sizes. Based on the on-load tap-changer as described above, the control method includes: Based on different voltage regulation targets, different voltage regulation gears corresponding to different voltage regulation targets are determined; different voltage regulation gears are formed by pairwise connection combinations among all the static contacts of the on-load tap-changer; Based on each voltage regulation step, the control device controls the two moving contact mechanisms to independently perform a power-off switching among the static contacts of the static contact unit, so that the two moving contact mechanisms are respectively electrically connected to the two static contacts corresponding to the voltage regulation step, and the voltage regulation amount of the voltage regulation step is output from the two moving contact mechanisms, thereby realizing variable-step voltage regulation.

[0013] Based on the same inventive concept, the present invention further provides a control system for a variable-step on-load tap-changer, including: A gear position determination module, configured to determine different voltage regulation steps corresponding to different voltage regulation targets based on different voltage regulation targets; different voltage regulation steps are formed by pairwise connection combinations among all the static contacts of the on-load tap-changer; A control module, configured to control the two moving contact mechanisms to independently perform a power-off switching among the static contacts of the static contact unit based on each voltage regulation step through a control device, so that the two moving contact mechanisms are respectively electrically connected to the two static contacts corresponding to the voltage regulation step, and the voltage regulation amount of the voltage regulation step is output from the two moving contact mechanisms, thereby realizing variable-step voltage regulation.

[0014] Based on the same inventive concept, the present invention further provides a computer device, including: one or more processors; A memory, configured to store one or more programs; When the one or more programs are executed by the one or more processors, the control method of a variable-step on-load tap-changer as described above is implemented.

[0015] Based on the same inventive concept, the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed, the control method of a variable-step on-load tap-changer as described above is implemented.

[0016] Compared with the closest prior art, the beneficial effects of the present invention are as follows: The present invention provides a on-load tap-changer with variable step size, which includes at least one static contact unit, two moving contact mechanisms that slide independently on the static contact unit, and a control device connected to the two moving contact mechanisms; the static contact unit includes three static contacts, and the three static contacts are correspondingly connected to the three input ends of the on-load tap-changer. All the static contacts are arranged in a circular array, and there is a spacing between two adjacent static contacts; during the sliding process of each moving contact mechanism, a non-powered conductive connection switching is achieved between each moving contact mechanism and each static contact; the moving contact mechanism is connected to the output end of the on-load tap-changer; through the quantity matching of the static contacts and the moving contact mechanisms, the independent movement characteristics of the two moving contact mechanisms, and the characteristics that all the static contacts are arranged in a circular array, the two moving contact mechanisms can each slide to the static contacts at any potential within one step of action. Through the pairwise combination connection of the static contacts at multiple potentials, the cooperation between the three input ends is realized, forming 7 voltage regulation grades, so as to realize variable step size voltage regulation and one-step switching to any voltage regulation grade, solving the disadvantages of traditional on-load tap-changers that cannot achieve stepped regulation, rapid regulation, variable step size regulation, etc.; it also solves the problems of a large number of switches, large floor area, and inability to be integrated with other primary equipment such as transformers when using multiple ordinary external switches to achieve rapid on-load regulation.

[0017] The present invention also provides a control method, system, device and medium for a on-load tap-changer with variable step size, including based on different voltage regulation targets, controlling the two moving contact mechanisms to independently switch non-powered between all the static contacts of the static contact unit through the control device, so that pairwise connection combinations of all the static contacts of the on-load tap-changer form multiple voltage regulation grades; the multiple voltage regulation grades correspond to different voltage regulation targets; the voltage regulation amounts of each voltage regulation grade are output from the two moving contact mechanisms to achieve variable step size voltage regulation; through the control method and system, the two moving contact mechanisms are each controlled to slide to the static contacts at any potential within one step of action, and through the pairwise combination connection of the static contacts at multiple potentials, the cooperation between the three input ends is realized, forming 7 voltage regulation grades, so as to realize variable step size voltage regulation and one-step switching to any voltage regulation grade, solving the disadvantages of traditional on-load tap-changers that cannot achieve stepped regulation, rapid regulation, variable step size regulation, etc., and can realize one-step switching to any grade, arbitrary variable step size, and rapid stepped regulation between any grades. Description of the Drawings

[0018] Figure 1 It is a structural schematic diagram of a on-load tap-changer with variable step size provided by the present invention; Figure 2 is Figure 1Schematic diagram of the positional relationship among the intermediate transition current limiter Z1, the intermediate transition current limiter Z2, the adaptive non-linear voltage limiter BV1, the adaptive non-linear voltage limiter BV2, the metal pole rod P1, and the metal pole rod P2; Figure 3 Schematic diagram of the structure of a variable-step on-load tap-changer combined with a controllable switch provided by the present invention; Figure 4 For Figure 3 Schematic diagram of the positional relationship among the intermediate transition current limiter Z1, the intermediate transition current limiter Z2, the adaptive non-linear voltage limiter BV1, the adaptive non-linear voltage limiter BV2, the metal pole rod P1, and the metal pole rod P2; Figure 5 Schematic diagram of the input-output state of a variable-step on-load tap-changer provided by the present invention; Figure 6 Schematic diagram of the application of a variable-step on-load tap-changer provided by the present invention Figure 1 ; Figure 7 Schematic diagram of the application of a variable-step on-load tap-changer provided by the present invention Figure 2 ; Figure 8 Schematic diagram of the control method flow of a variable-step on-load tap-changer provided by the present invention; Figure 9 For Figure 1 Partial schematic diagram at the upper right corner of the sliding switching process of the moving contact mechanism in Figure 10 For Figure 3 Partial schematic diagram at the upper right corner of the sliding switching process of the moving contact mechanism combined with a controllable switch in Figure 11 Schematic diagram of the control system structure of a variable-step on-load tap-changer provided by the present invention; Figure 12 Schematic diagram of the structure of an electronic device provided by the present invention; Wherein, 1. Moving contact mechanism; 2. Static contact; 3. Turntable; 4. Transition current limiter; 5. Adaptive non-linear voltage limiter; 6. Metal pole rod; 7. Controllable switch; 8. Turntable driver; 9. Interconnected busbar; 10. Controller. Specific embodiments

[0019] The following further elaborates on the specific embodiments of the present invention with reference to the accompanying drawings.

[0020] Embodiment 1: A variable-step on-load tap-changer provided by the present invention, as Figure 1 shown, includes: at least one static contact unit, two moving contact mechanisms 1 that independently slide on the static contact unit, and a control device connected to the two moving contact mechanisms 1; The static contact unit includes three static contacts 2, and the three static contacts 2 are correspondingly connected to three input ends of the on-load tap-changer. All the static contacts 2 are arranged in a circular array, and there is a spacing between two adjacent static contacts; During the sliding process of each moving contact mechanism 1, a non-powered-off conductive connection switching is achieved between each moving contact mechanism 1 and each static contact 2; the moving contact mechanism 1 is connected to the output end of the on-load tap-changer.

[0021] In the present invention, through the matching of the numbers of the static contacts and the moving contact mechanisms, the independent moving characteristics of the two moving contact mechanisms, and the feature that all the static contacts are arranged in a circular array, the two moving contact mechanisms can each slide to the static contacts at any potential within one step of movement. Through the pairwise combination connection of the static contacts at multiple potentials, the cooperation between the three input ends is realized, and seven voltage regulation gears are formed, so as to realize variable-step voltage regulation and one-step switching to any voltage regulation gear, solving the disadvantages that the traditional on-load tap-changer cannot achieve cross-range regulation, rapid regulation, variable-step regulation, etc.; it also solves the problems of a large number of switches, large floor area, and inability to be integrated with other primary equipment such as transformers when using multiple ordinary external switches to achieve rapid on-load regulation, and is used in application fields such as voltage / power flow / power regulation of transmission / distribution networks and railway traction, new energy power stations, industrial and commercial power supply voltage regulation, load voltage regulation, smelting process regulation, etc.

[0022] In this embodiment, each static contact 2 has two conductive surfaces, and the two conductive surfaces of all the static contacts 2 respectively form two circumferential surfaces, and the two moving contact mechanisms 1 respectively slide independently along the two circumferential surfaces.

[0023] It should be noted that all the static contact units constitute a static contact mechanism, and the two circumferential surfaces are the two circumferential surfaces of the static contact mechanism. The number of static contacts 2 in the static contact mechanism is 3*N, N≥1, and N is the number of static contact units; In this embodiment, preferably, as Figure 1 shown, the static contact 2 is a double-sided static contact. The double-sided static contact includes an inner static contact and an outer static contact. The two contacts are directly connected by a conductor and form an integral structure in an I-shaped structure with the same potential; in addition, the inner static contact, the outer static contact, and the conductor can also be the inner and outer two conductive surfaces of the same conductor; All the static contacts 2 form a ring. The outer conductive surface or the outer static contact forms the circumferential surface on the outer side of the ring, and the inner conductive surface or the inner static contact forms the circumferential surface on the inner side of the ring. The two moving contact mechanisms 1 are respectively arranged on the inner and outer sides of the ring and are arranged in a three-layer sleeve type, with a compact installation structure and a reasonable layout; In another possible implementation, both circumferential surfaces are located on the same side of the ring, i.e., the outer side or the inner side; the diameters of the two circumferential surfaces are the same and they are arranged in layers; at this time, both moving contact mechanisms 1 are located on the same side of the ring, and are arranged in a two-layer sleeve type with the static contact mechanism, and the two moving contact mechanisms 1 and the two circumferential surfaces are arranged in corresponding layers. In another possible implementation, the two circumferential surfaces are arranged on two opposite ring width surfaces of the ring; at this time, one moving contact mechanism 1, the static contact mechanism, and the other moving contact mechanism 1 are arranged in sequence along the axial direction of the static contact mechanism.

[0024] In this embodiment, each of the moving contact mechanisms 1 includes a turntable 3 coaxially arranged with the circumferential surface, a transition current limiter 4 electrically connected and fixed on the turntable 3, an adaptive non-linear voltage limiter 5, and a metal pole rod 6. One ends of the transition current limiter 4, the adaptive non-linear voltage limiter 5, and the metal pole rod 6 are arranged in sequence along the circumferential direction of the turntable 3, and the other ends of the transition current limiter 4, the adaptive non-linear voltage limiter 5, and the metal pole rod 6 are in sliding contact with the conductive surface; the distance between the transition current limiter 4 and the metal pole rod 6 is less than the width of the conductive surface and greater than the set electrical insulation clearance; the turntable 3 is connected to the output end of the on-load tap-changer.

[0025] It should be noted that the three layout relationships between the two moving contact mechanisms 1 and the static contact mechanism can be regarded as the three layout relationships between the two turntables 3 in the two moving contact mechanisms 1 and the static contact mechanism. The transition current limiter 4, the adaptive non-linear voltage limiter 5, and the metal pole rod 6 together constitute a sliding mechanism, which is arranged between the turntable 3 and the static contact mechanism and is in sliding cooperation with the conductive surface of the static contact 2.

[0026] In this embodiment, the two turntables 3 in the two moving contact mechanisms 1 are respectively denoted as the inner turntable and the outer turntable. Both turntables 3 can rotate clockwise and counterclockwise, and the inner / outer turntable serves as the two output ends of this on-load tap-changer; as Figure 2 shown, the transition current limiter 4 includes a transition current limiter Z1 and a transition current limiter Z2, the adaptive non-linear voltage limiter 5 includes an adaptive non-linear voltage limiter BV1 and an adaptive non-linear voltage limiter BV2, and the metal pole rod 6 includes a metal pole rod P1 and a metal pole rod P2; Z1, BV1, and P1 constitute an inner sliding mechanism arranged on the inner turntable, and Z2, BV2, and P2 constitute an outer sliding mechanism arranged on the outer turntable.

[0027] The transition impedance, that is, the transition current limiter 4 has the characteristic of limiting current, is composed of elements with resistance, inductance, or capacitance characteristics. One end of it is fixedly electrically connected to the turntable 3, and the other end is connected to a conductive sliding block, and the conductive sliding block is used for sliding contact with the static contact 2. The metal pole bar 6 is composed of a metal material with good electrical conductivity, such as a copper conductor, etc. One end of it is fixedly conductively connected to the turntable 3, and the other end is connected to the conductive sliding block, and the conductive sliding block is used for sliding contact with the static contact 2.

[0028] One end of the adaptive non-linear voltage limiter 5 is fixedly conductively connected to the turntable 3, and the other end is connected to the conductive sliding block, and the conductive sliding block is used for sliding contact with the static contact 2, which can realize the protection against overvoltage; In another possible implementation manner, the above-mentioned sliding mechanism can only adopt the transition current limiter 4 and the metal pole bar 6, and can also realize the switching of the continuously conductive connection during the sliding process with each of the static contacts 2 and the one-step switching between any voltage adjustment gears, but it is easy to cause the transition current limiter 4 to fuse; In this embodiment, preferably, the adaptive non-linear voltage limiter 5 is arranged between the transition current limiter 4 and the metal pole bar 6, which can realize the protection against overvoltage and avoid the transition current limiter 4 from fusing.

[0029] In this embodiment, when the voltage between the adaptive non-linear voltage limiter 5 and the static contact 2 in contact with it is greater than or equal to the set voltage protection value, the impedance of the adaptive non-linear voltage limiter 5 is less than the set impedance lower limit value; When the voltage between the adaptive non-linear voltage limiter 5 and the static contact 2 in contact with it is less than the voltage protection value, the impedance of the adaptive non-linear voltage limiter 5 is greater than the set impedance upper limit value.

[0030] Specifically, the adaptive non-linear voltage limiter 5 has an over-voltage protection characteristic of limiting voltage, which is used to protect against over-voltage when the switch is abnormal; during the switching process, for example, when only the transition resistor, i.e., the branch of the transition current limiter 4, is powered, such as when the metal pole rod 6 may be in a suspended state between two static contacts. If the transition impedance is burned out due to overcurrent or other reasons, the entire power supply circuit will present an open circuit state at this time, that is, it is easy to have an excessive voltage between the moving and static contacts, exceeding the set voltage protection value, which will cause over-voltage breakdown hazards; the usually designed voltage protection value is a transition interval, for example, 1800V - 2200V. For example, the pole voltage between the moving and static contacts is 600V under normal conditions; when the voltage between the moving and static contacts exceeds or equals 2200V, the adaptive non-linear voltage limiter 5 automatically adjusts its impedance characteristic and presents a low-impedance characteristic. At this time, the voltage between the moving and static contacts is limited within the safe range of 2200V; if it is lower than 1800V, that is, the adaptive non-linear voltage limiter 5 presents a high-impedance characteristic, it can be understood that the state between the moving and static contacts remains unchanged at this time, and the voltage between the moving and static contacts is less than 1800V; if it is between 1800V - 2200V, it is in the state of the transition resistor, and the voltage between the moving and static contacts is limited between 1800V - 2200V. If the control device detects that the voltage between the moving and static contacts appears in the state of 600V - 2200V, it can be determined that there is a problem with the over-transition circuit of the moving contact, and then the switching needs to be stopped; this solves the safety problems such as over-voltage damage to the switch and transformer short-circuit caused by the inability of the traditional on-load tap-changer to realize the open circuit of the switch regulating circuit.

[0031] In this embodiment, the adaptive non-linear voltage limiter 5 includes one of the following: Zener diode, switching thyristor, varistor.

[0032] In this embodiment, when the number of the static contact units is two or more, the three static contacts 2 in each static contact unit are coded in ascending order, and the multiple static contact units are coded cyclically. The static contacts 2 with the same code in each static contact unit are connected through the interconnection bus 9, and after the static contacts 2 with the same code are connected, they are correspondingly connected to the three input terminals of the on-load tap-changer, and the three input terminals are connected to different taps of the power supply or the transformer winding.

[0033] Specifically, at this time, all the static contacts 2 are arranged in a circular form, and each static contact 2 is also an electrode. Each static contact / electrode is coded in a specific cyclic coding form, and the coding method is a cyclic method along the circumferential direction, either clockwise or counterclockwise. For example, Figure 1 As shown in the figure, the cyclic coding of all the static contacts 2 in the clockwise direction along the circumference is: ①, ②, ③, ①, ②, ③... The total number of electrodes, that is, all the static contacts 2, is 3*N, where N≥1 and N is the number of static contact units;Figure 1 The encodings ①, ②, and ③ in it are both the numbers of the static contacts 2 where the encodings are located and the numbers of the interconnected busbars 9 where the encodings are located; The static contacts / electrodes with the same encoding are connected by the conductive interconnected busbar 9 and have the same potential; the number of interconnected busbars 9 is the same as the number of types of static contact encodings. The interconnected busbars 9 include interconnected busbar ①, interconnected busbar ②, and interconnected busbar ③, and each interconnected busbar is independent of each other; after the interconnection, a terminal is led out, and the encoding of this terminal is the same as the encoding of the static contact / electrode. At the same time, this terminal serves as the input end of the switch and is used to connect to a power source or a transformer winding; as Figure 1 shown, all the electrodes with encoding ① are connected by interconnected busbar ①, all the electrodes with encoding ② are connected by interconnected busbar ②, and all the electrodes with encoding ③ are connected by interconnected busbar ③. After connection, terminals 1, 2, and 3 are respectively led out as input end ①, input end ②, and input end ③; In this embodiment, as Figure 3 shown, a controllable switch 7 is provided on the transition current limiter 4 and the metal pole rod 6.

[0034] In this embodiment, as Figure 3 and Figure 4 shown, the controllable switch 7 includes controllable switches V11, V12, V21, and V22. Among them, the controllable switches V11 and V12 are respectively connected in series on the transition current limiter Z1 and the metal pole rod P1, and the controllable switches V21 and V22 are respectively connected in series on the transition current limiter Z2 and the metal pole rod P2; It should be noted that the controllable switch 7 can be an electrically controlled switch or a mechanically linked controlled switch using the sliding characteristics of the sliding mechanism. When the sliding mechanism rotates, the mechanical opening and closing of the controllable switch 7 can be achieved through the cooperation of switch control structures such as switch pressing keys and bumps at fixed positions.

[0035] In this embodiment, the control device includes a turntable driver 8 connected to the turntable 3 and a controller 10 electrically connected to the turntable driver 8.

[0036] In this embodiment, when the controllable switch 7 is provided, the control device further includes a switch driving unit required to control the controllable switch 7.

[0037] The turntable driver 8 drives the inner turntable and the outer turntable respectively to realize gear shifting adjustment by linking the above-mentioned sliding mechanism; the control device is also used to receive external instructions and issue them to the inner and outer turntable drivers respectively after formula decomposition, and is also used to identify and process various states inside the switch.

[0038] When the present invention is actually used, as Figure 5As shown, a voltage source u1 is connected between input terminal ① and input terminal ②, and a voltage source u2 is connected between input terminal ② and input terminal ③. Then, through the control device, the turntable driver 8 drives the turntable 3 to drive the sliding mechanism to rotate. When it rotates to different static contact 2 positions, 7 voltage states u, that is, 7 gears, can be output between output terminal ① and output terminal ②, including: (1) When the inner turntable drives the inner sliding mechanism to rotate to the static contact 2 encoded as ① (hereinafter referred to as electrode ①), and the outer turntable drives the outer sliding mechanism to rotate to the static contact 2 encoded as ② (hereinafter referred to as electrode ②), the output voltage between output terminal ① and output terminal ② is u1; It should be noted that the implementation principle of one-step switching between any voltage adjustment gears is illustrated by taking the sliding of the outer sliding mechanism of this gear as an example: As Figure 1 shown, before the gear is switched, when the outer sliding mechanism is located at electrode ①, the outer turntable drives the outer sliding mechanism to rotate clockwise by a step length of the width of a static contact to electrode ② to achieve one-step switching in place; before the gear is switched, when the outer sliding mechanism is located at electrode ③, the outer turntable drives the outer sliding mechanism to rotate counterclockwise by a step length of the width of a static contact to electrode ② to achieve one-step switching in place; Combining the same principle to control the sliding of the inner sliding mechanism, so as to realize any combination of the inner and outer static contacts and achieve one-step switching in place between any voltage adjustment gears; (2) When the inner turntable drives the inner sliding mechanism to rotate to electrode ②, and the outer turntable drives the outer sliding mechanism to rotate to electrode ①, the output voltage between output terminal ① and output terminal ② is -u1; (3) When the inner turntable drives the inner sliding mechanism to rotate to electrode ②, and the outer turntable drives the outer sliding mechanism to rotate to the static contact 2 encoded as ③ (hereinafter referred to as electrode ③), the output voltage between output terminal ① and output terminal ② is u2; (4) When the inner turntable drives the inner sliding mechanism to rotate to electrode ③, and the outer turntable drives the outer sliding mechanism to rotate to electrode ②, the output voltage between output terminal ① and output terminal ② is -u2; (5) When the inner turntable drives the inner sliding mechanism to rotate to electrode ①, and the outer turntable drives the outer sliding mechanism to rotate to electrode ③, the output voltage between output terminal ① and output terminal ② is u1 + u2; (6) When the inner turntable drives the inner sliding mechanism to rotate to electrode ③, and the outer turntable drives the outer sliding mechanism to rotate to electrode ①, the output voltage between output terminal ① and output terminal ② is -(u1 + u2); (7) When the inner sliding mechanism and the outer sliding mechanism rotate to the static contacts with the same encoding, including when the inner turntable drives the inner sliding mechanism to rotate to electrode ① and the outer turntable drives the outer sliding mechanism to also rotate to electrode ①; when the inner turntable drives the inner sliding mechanism to rotate to electrode ② and the outer turntable drives the outer sliding mechanism to also rotate to electrode ②; when the inner turntable drives the inner sliding mechanism to rotate to electrode ③ and the outer turntable drives the outer sliding mechanism to also rotate to electrode ③; the output voltage between output terminal ① and output terminal ② is 0.

[0039] Specifically, when the present invention is used, two connection methods with the outside can be adopted. The first connection method is as Figure 6 shown. Multiple on-load tap-changers are used. The input terminals of each on-load tap-changer are connected to different taps of the transformer winding or the power supply. The output terminals of each on-load tap-changer are connected in series to form a total output terminal. By adjusting each on-load tap-changer, different voltages are taken from each transformer winding and then connected in series and superimposed on the output terminal to realize the change of the input voltage of the transformer.

[0040] The second connection method is as Figure 7 shown. The input terminal of the on-load tap-changer is connected to different taps of the primary regulating winding of the transformer. After the output terminal of the on-load tap-changer is connected in series with the primary main winding of the transformer, it serves as the voltage input terminal of the primary side of the transformer. By adjusting the on-load tap-changer, the ratio of the total number of turns of the primary winding to the number of turns of the secondary winding of the transformer can be changed, thereby realizing the regulation of the output voltage of the secondary side of the transformer.

[0041] In the above two connection methods, the winding turn ratio between input terminal ①② and input terminal ②③ of the on-load tap-changer is 1:2, 1:1.5, etc.; correspondingly, when a voltage source is connected between the input terminals, the voltage ratio of voltage source u1 to voltage source u2 is 1:2, 1:1.5, etc.; when the turn ratio or voltage ratio is 1:1.5, the on-load tap-changer can realize non-uniform variable step voltage regulation, that is, the step size changes at non-fixed intervals, which is suitable for different scenario requirements.

[0042] The use of the on-load tap-changer of the present invention is not limited to single-phase power systems, but also applicable to three-phase or polyphase systems. Embodiment schemes with similar principles and usages are also within the protection scope of this scheme.

[0043] Embodiment 2: Based on the same inventive concept, the present invention also provides a control method for a variable step on-load tap-changer, as Figure 8 shown. Based on the on-load tap-changer in the above embodiment, the control method includes: S1. Based on different voltage regulation targets, determine different voltage regulation gears corresponding to different voltage regulation targets; different voltage regulation gears are formed by pairwise connection combinations of all static contacts 2 of the on-load tap-changer; S2. Based on each voltage regulation gear, the control device controls the two moving contact mechanisms 1 to independently perform a non-powered switching among the static contacts 2 of the static contact unit, so that the two moving contact mechanisms 1 are respectively electrically connected to the two static contacts 2 corresponding to the voltage regulation gear, and the voltage regulation amount of the voltage regulation gear is output from the two moving contact mechanisms 1 to achieve variable-step voltage regulation.

[0044] It should be noted that the control device controls the two moving contact mechanisms 1 to independently perform a non-powered switching among the static contacts 2 of the static contact unit. Therefore, when the number of the static contact units is multiple, the two moving contact mechanisms 1 can both slide and switch across the static contact units, so as to achieve a one-step switching in place between any voltage regulation gears.

[0045] In the above S2, when the control device controls the two moving contact mechanisms 1 to independently perform a non-powered switching among the static contacts 2 of the static contact unit, the process of the sliding mechanism of the moving contact mechanism 1 switching from the current static contact 2 to the adjacent static contact 2 without power interruption includes: When the rotation direction is from the transition current limiter 4 to the metal pole bar 6 (for example, Figure 1 the clockwise direction in the example), driven by the turntable 3, the metal pole bar 6 first moves from the current static contact 2 to the adjacent static contact 2, and the transition current limiter 4 and the adaptive non-linear voltage limiter 5 move synchronously with the metal pole bar 6. When the metal pole bar 6 breaks away from the current static contact 2 and has not reached the adjacent static contact 2, the current passes through the transition current limiter 4 to maintain the power supply continuity, so that the current is not interrupted when the metal pole bar 6 breaks away from the current static contact 2; the adaptive non-linear voltage limiter 5 prevents the circuit from being damaged by overvoltage breakdown due to abnormal resistance open circuit during the switching process. When the rotation direction is from the metal pole bar 6 to the transition current limiter 4 (for example, Figure 1 the counterclockwise direction in the example), driven by the turntable 3, the transition current limiter 4 first moves from the current static contact 2 to the adjacent static contact 2, and the adaptive non-linear voltage limiter 5 and the metal pole bar 6 move synchronously with the transition current limiter 4. The transition current limiter 4 first contacts the adjacent static contact 2 to establish a path in advance, so that the current is not interrupted when the metal pole bar 6 breaks away from the current static contact 2; the adaptive non-linear voltage limiter 5 prevents the circuit from being damaged by overvoltage breakdown due to abnormal resistance open circuit during the switching process.

[0046] Specifically, to achieve gear shifting, taking the clockwise sliding of the outer layer sliding mechanism as an example, the process of its non-powered switching is described as follows: As Figure 9 shown, the slip switching steps are a1→b1→c1→d1→e1, and the step a1 shows the initial position, which is at the position of electrode ②; Turn right to the position shown in step b1, where the metal pole P2 is located between electrode ② and electrode ③. At this time, the current passes through the transition impedance Z2 to ensure continuous power supply during the switching process without power interruption. The adaptive non-linear voltage limiter BV2 can prevent overvoltage breakdown and damage to the switch caused by abnormal resistance open circuit in this process; Continue to turn right to the position shown in step c1, where the metal pole P2 is located at electrode ③. At this time, the transition impedance Z2 limits the short-circuit current between electrode ② and electrode ③, and the output power supply is provided by electrode ③; Continue to turn right to the position shown in step d1, where the metal pole P2 is located at electrode ③. At this time, the transition impedance Z2 is between electrode ② and electrode ③, and the short-circuit current disappears. The output power supply is provided by electrode ③; Continue to turn right to the position shown in step e1, where the transition impedance Z2, the metal pole P2, and the adaptive non-linear voltage limiter BV2 are all located at electrode ③. Thus, the position switching from electrode ② to electrode ③ is completed; The process of rotating left (i.e., counterclockwise) and the switching process of the inner sliding mechanism are similar to the above process.

[0047] The switch includes an inner driver and an outer driver. The inner driver is used to drive the inner turntable to rotate, and the outer driver is used to drive the outer turntable to rotate, and has functions of rotational angle positioning, forward / backward rotation, and rotational position feedback; The switch includes a set of control systems for issuing control commands to the inner / outer drivers, controlling the rotational angle and rotation direction of each driver, receiving various status feedback information, and implementing protection and alarm functions.

[0048] Special note: Driven by the turntable, the sliding mechanism can rotate (forward or backward) to any one of electrode ①, electrode ②, and electrode ③ at one time.

[0049] To achieve gear shifting, taking the clockwise sliding of the outer sliding mechanism as an example in the case of the variable-step rapid on-load tap-changer combined with the controllable switch 7, the process of its continuous power switching is described as follows: As Figure 10 shown, the slip switching steps are a2→b2→c2→d2→e2→f2→g2→h2→i2. The position shown in step a2 is the initial position, where the outer sliding mechanism is located at electrode ②, and its controllable switches V21 and V22 are in the on state; As shown in step b2, the controllable switch V22 changes from the conducting state to the off state, and the state of the controllable switch V21 remains unchanged and is in the conducting state. Among them, when the controllable switch is a mechanical switch, the conducting surface of the static contact 2 is wider. The outer sliding mechanism rotates to the position shown in step b2 to move the metal pole rod P2 from the middle part of the electrode ② to the edge of the electrode ②, and the disconnection of the controllable switch V22 is realized through the switch control structure located at the edge of the electrode ②. Rotate to the position shown in step c2. The metal pole rod P2 is located between the electrode ② and the electrode ③. The state of the controllable switch V22 remains unchanged and is in the off state, ensuring that there is no current and no arcing when the metal pole rod P2 leaves the electrode ②, improving the service life of the switch. The state of the controllable switch V21 remains unchanged and is in the conducting state. At this time, the current passes through the transition impedance Z2 to ensure continuous power supply without power loss during the switching process. The adaptive non-linear voltage limiter BV2 can prevent the circuit from being damaged by overvoltage breakdown due to abnormal resistance disconnection during this process. Rotate to the position shown in step d2. The metal pole rod P2 contacts the electrode ③. The state of the controllable switch V22 remains unchanged and is in the off state, ensuring that there is no current and no arcing when the metal pole rod P2 contacts the electrode ③, improving the service life of the switch. The state of the controllable switch V21 remains unchanged and is in the conducting state. Rotate to the position shown in step e2. The adaptive non-linear voltage limiter BV2 is located between the electrode ② and the electrode ③. The state of the controllable switch V22 of the sliding mechanism changes from the off state to the conducting state, and the state of the controllable switch V21 remains unchanged and is in the conducting state. At this time, a short-circuit circulating current appears between the switches V22 and V21. The transition impedance Z2 limits the short-circuit circulating current between the electrode ② and the electrode ③ to limit the generation of excessive circulating current, and the output power supply is supplied by the electrode ③. Rotate to the position shown in step f2. The adaptive non-linear voltage limiter BV2 contacts the electrode ③. The state of the controllable switch V21 of the sliding mechanism changes from the conducting state to the off state. At this time, the short-circuit circulating current disappears, and the state of the controllable switch V22 remains unchanged and is in the conducting state. Rotate to the position shown in step g2. The transition impedance Z2 is located between the electrode ② and the electrode ③. The state of the controllable switch V21 of the sliding mechanism remains unchanged and is in the off state, ensuring that there is no current and no arcing when the transition impedance Z2 leaves the electrode ②, improving the service life of the switch. The state of the controllable switch V22 remains unchanged and is in the conducting state, and the output power supply is supplied by the electrode ③. Rotate to the position shown in step h2. The transition impedance Z2 contacts the electrode ③. The state of the controllable switch V21 of the sliding mechanism remains unchanged and is in the off state, ensuring that there is no current and no arcing when it contacts the electrode ③, improving the service life of the switch. The state of the controllable switch V22 remains unchanged and is in the conducting state. Subsequently, as shown in step i2, the state of the controllable switch V21 of the sliding mechanism changes from off to on, providing an initial state for the next rotation and switching. The state of the controllable switch V22 remains unchanged and is in the on state. Among them, when the controllable switch is a mechanical switch, the conductive surface of the static contact 2 is wider. The outer sliding mechanism rotates to the position shown in step i2 to move the transition impedance Z2 from the edge of the electrode ③ to the middle part of the electrode ③, and the conduction of the controllable switch V21 is realized through the switch control structure located at the edge of the electrode ③.

[0050] The reverse rotation and switching gear is opposite to the above process, and the transition process is the same as the above switching mechanism, except that the transition resistance branch acts first and the metal pole rod branch acts later.

[0051] Embodiment 3 Based on the same inventive concept, the present invention also provides a control system for a on-load tap-changer with variable step size, as Figure 11 shown, including: A gear position determination module, configured to determine different voltage regulation gears corresponding to different voltage regulation targets based on different voltage regulation targets; different voltage regulation gears are formed by pairwise connection combinations among all the static contacts 2 of the on-load tap-changer; A control module, configured to, based on each voltage regulation gear, control two moving contact mechanisms 1 to independently and continuously switch between the respective static contacts 2 of the static contact unit through a control device without power interruption, so that the two moving contact mechanisms 1 are electrically connected to the two static contacts 2 corresponding to the voltage regulation gear respectively, and the voltage regulation amount of the voltage regulation gear is output from the two moving contact mechanisms 1 to achieve variable step size voltage regulation.

[0052] Embodiment 4 As Figure 12 shown, the present invention also provides an electronic device, which may be a computer device, a single-chip microcomputer device, a smart mobile device, etc. The electronic device in this embodiment may include a processor, a memory, a transceiver component, etc. The memory, the processor, and the transceiver component are connected through a bus; the memory can be used to store an execution program, and an exemplary execution program may include instructions; the processor is configured to execute the instructions stored in the memory. The memory can also be used to store data, and the data can be called and / or modified when the instructions are executed.

[0053] The processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of a control method for a tap-changer with variable step size in the above embodiments.

[0054] Embodiment 5 Based on the same inventive concept, the present invention also provides a readable storage medium, specifically a storage medium readable by an electronic device (Memory). The storage medium readable by the electronic device is a memory device in the electronic device, and is used to store programs and data. It can be understood that the storage medium here can include both the built-in storage medium in the electronic device, and of course can also include the extended storage medium supported by the electronic device. The storage medium provides a storage space, and this storage space stores the operating system of the terminal. And, one or more instructions suitable for being loaded and executed by the processor are also stored in this storage space. These instructions can be one or more execution programs (including program codes). It should be noted that the storage medium here can be a high-speed RAM memory, or a non-volatile memory, such as at least one disk memory. By loading and executing one or more instructions stored in the storage medium by the processor, the steps of a control method for a tap-changer with variable step size in the above embodiments can be implemented.

[0055] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0056] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or in multiple blocks.

[0057] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or in multiple blocks.

[0058] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operating steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or in multiple blocks.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the scope of its protection. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that after reading the present invention, various changes, modifications, or equivalent replacements can still be made to the specific implementation manners of the application. However, these changes, modifications, or equivalent replacements are all within the scope of the protection of the claims of the present invention.

Claims

1. A variable step-length on-load voltage regulating switch, characterized in that: include: At least one stationary contact unit, two moving contact mechanisms (1) that slide independently on the stationary contact unit, and a control device connected to the two moving contact mechanisms (1); The stationary contact unit comprises three stationary contacts (2), the three stationary contacts (2) being connected to three input terminals of the on-load tap-changing switch correspondingly, all the stationary contacts (2) being arranged in a circular array, and a spacing being provided between two adjacent stationary contacts; Each of the moving contact mechanisms (1) realizes a conductive connection switch with each of the static contacts (2) without interruption of power supply during the sliding process; the moving contact mechanism (1) is connected to the output end of the on-load voltage regulator.

2. A variable step-length on-load voltage regulating switch as claimed in claim 1, characterized in that: Each of the stationary contacts (2) has two conductive surfaces, and the two conductive surfaces of all the stationary contacts (2) respectively form two circumferential surfaces, and the two moving contact mechanisms (1) slide independently along the two circumferential surfaces.

3. A variable step-length on-load voltage regulating switch as claimed in claim 2, characterized in that: Each of the moving contact mechanisms (1) comprises a rotating disk (3) arranged coaxially with the circumferential surface, a transition current limiter (4) conductively connected and fixed on the rotating disk (3), an adaptive nonlinear voltage limiter (5) and a metal pole (6); The transition current limiter (4), the adaptive nonlinear voltage limiter (5) and one end of the metal pole (6) are arranged in sequence along the circumferential direction of the rotating disk (3), and the other ends of the transition current limiter (4), the adaptive nonlinear voltage limiter (5) and the metal pole (6) are in sliding contact with the conductive surface; the spacing between the transition current limiter (4) and the metal pole (6) is smaller than the width of the conductive surface and larger than a set electrical insulation clearance; the rotating disk (3) is connected to the output end of the on-load voltage regulator.

4. A variable step-length on-load voltage regulating switch as claimed in claim 3, characterized in that: When the voltage between the adaptive nonlinear voltage limiter (5) and the static contact (2) in contact with it is greater than or equal to a set voltage protection value, the impedance of the adaptive nonlinear voltage limiter (5) is less than a set impedance lower limit value; When the voltage between the adaptive nonlinear voltage limiter (5) and the static contact (2) in contact with it is less than the voltage protection value, the impedance of the adaptive nonlinear voltage limiter (5) is greater than a set impedance upper limit value.

5. A variable step-length on-load voltage regulating switch as claimed in claim 4, characterized in that: The adaptive nonlinear voltage limiter (5) comprises the following: Zener diodes, thyristors, varistors.

6. A variable step-length on-load voltage regulating switch according to any one of claims 1 to 5, characterized in that: When the number of the static contact units is two or more, the three static contacts (2) in each static contact unit are coded in ascending order, and the static contact units are coded cyclically. The static contacts (2) with the same coding in each static contact unit are connected through an interconnecting busbar (9). After being connected, the static contacts (2) with the same coding are correspondingly connected to the three input terminals of the on-load tap-changing switch, and the three input terminals are connected to different taps of the power supply or transformer winding.

7. A variable step-length on-load voltage regulating switch as claimed in claim 3, characterized in that: The transition current limiter (4) and the metal pole (6) are provided with a controllable switch (7).

8. A variable step-length on-load voltage regulating switch according to any one of claims 3 to 5, characterized in that: The control device comprises a turntable drive (8) connected to the turntable (3) and a controller (10) electrically connected to the turntable drive (8).

9. A control method for a variable step-size on-load voltage regulator, characterized in that: Based on the on-load voltage regulating switch according to any one of claims 1 to 8, the control method comprises: Based on different voltage regulation targets, different voltage regulation gears corresponding to the different voltage regulation targets are determined; the different voltage regulation gears are formed based on the combination of all the static contacts (2) of the on-load voltage regulating switch being connected in pairs; Based on each voltage adjustment gear, the two moving contact mechanisms (1) are controlled by a control device to switch between the static contacts (2) of the static contact unit independently and continuously, so that the two moving contact mechanisms (1) are respectively electrically connected to the two static contacts (2) corresponding to the voltage adjustment gear, and the voltage adjustment amount of the voltage adjustment gear is output from the two moving contact mechanisms (1), thereby realizing variable step length voltage regulation.

10. A control system for a variable step-size on-load voltage regulator, characterized in that: include: A gear determination module, used for determining different voltage regulation gears corresponding to different voltage regulation targets based on different voltage regulation targets; the different voltage regulation gears are formed based on the combination of two-by-two connections between all the static contacts (2) of the on-load voltage regulating switch; A control module is used for controlling two moving contact mechanisms (1) to independently switch between the static contacts (2) of a static contact unit based on each voltage adjustment gear through a control device, so that the two moving contact mechanisms (1) are respectively electrically connected to the two static contacts (2) corresponding to the voltage adjustment gear, and the voltage adjustment amount of the voltage adjustment gear is output from the two moving contact mechanisms (1), thereby realizing variable step-length voltage regulation.

11. An electronic device, characterized in that: include: at least one processor and memory; The memory and the processor are connected via a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, the control method of the variable-step-size on-load voltage regulating switch as claimed in claim 9 is implemented.

12. A readable storage medium, characterized in that: An execution program is stored thereon, and when the execution program is executed, the control method of the variable step-size on-load voltage regulating switch as claimed in claim 9 is implemented.

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