Distribution transformer on-load voltage regulation device and voltage regulation intelligent control method

Abstract

The invention provides a distribution transformer on-load voltage regulation device and a voltage regulation intelligent control method. The device comprises a distribution transformer primary main winding, at least two sets of distribution transformer primary tapping windings and mechanical locking self-holding vacuum contactor contacts (K11, K12), (K21, K22) and (K31, K32) which are connected with neutral points of the windings. At least two groups of transition impedances, and mechanical latching self-holding vacuum contactor contacts (K middle 11, K middle 12) (K middle 21, K middle 22) connected with neutral points of the groups of transition impedances; each distribution transformer winding and the transition impedance are respectively provided with a corresponding current transformer used for detecting current passing through each contact, in this way, it can be guaranteed that no electrical short circuit occurs when a tapping winding is connected or quitted, and short-time power failure of a user is not caused by gear shifting of the distribution transformer.

Description

Technical Field

[0001] The present disclosure relates to the technical field of on-load voltage regulation of distribution transformers, and in particular to an on-load voltage regulation device of a distribution transformer and an intelligent voltage regulation control method. Background Art

[0002] With the large-scale promotion and application of distributed photovoltaic and wind power new energy technologies, the voltage fluctuation range and frequency on the low-voltage side of the distribution system have increased significantly, directly affecting the normal electricity consumption of users. Complaints caused by unqualified voltage of rural public distribution transformers have increased significantly. Based on the service tenet of the people's power industry for the people, the power grid has implemented full-caliber voltage assessment management. Voltage regulation of public distribution transformers is one of the effective means to solve the voltage problem of users. At present, the absolute majority of public distribution transformers adopt no-load voltage regulation. No-load voltage regulation of public distribution transformers will cause short-term power outages for users. This is not only not allowed by the distribution network power supply reliability assessment, but also in the face of numerous public distribution transformers, limited distribution operation and maintenance personnel are simply unable to meet the timely voltage regulation needs of public distribution transformers. It is imperative to implement on-load voltage regulation of distribution transformers. Summary of the invention

[0003] In view of the defects of the prior art, the present application proposes an on-load voltage regulating device and an intelligent voltage regulating control method for a distribution transformer, aiming to solve the problems that the existing off-load voltage regulation of public distribution transformers will cause short-term power outages for users and the limited distribution operation and maintenance personnel are simply unable to meet the timely voltage regulation needs of public distribution transformers.

[0004] According to a first aspect of the present disclosure, there is provided an on-load voltage regulating device for a distribution transformer, the device comprising: Distribution transformer primary main winding (A1, B1, C1); At least two groups of distribution transformer primary tap windings, including a first group of primary tap windings (A2, B2, C2) and a second group of primary tap windings (A3, B3, C3); Mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of the primary main winding of the distribution transformer; Mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of the first set of primary tap windings; Mechanically locked self-holding vacuum contactor contacts (K31, K32) connected to the neutral point of the second set of primary tap windings; At least two groups of transition impedances (Z1, Z2), including a first group of transition impedances Z1 and a second group of transition impedances Z2; mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of transition impedance Z1; mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of transition impedance Z2; Each transformer winding and transition impedance is equipped with a corresponding current transformer to detect the current passing through each contact. When the current of each contact is detected to pass through the zero point, the corresponding mechanical locking self-holding vacuum contactor contact is disconnected.

[0005] According to the aspects described above and any possible implementation, an implementation is further provided, wherein the first group of transition impedances Z1 is associated with the first group of primary tap windings (A2, B2, C2), the second group of transition impedances Z2 is associated with the second group of primary tap windings (A3, B3, C3), and each group of transition impedances is connected to the circuit through a corresponding mechanically locked self-holding vacuum contactor contact. According to the above aspects and any possible implementation manner, an implementation manner is further provided, wherein the first group of transition impedances Z1 and the second group of transition impedances Z2 are both equal-value impedances.

[0006] According to the above aspects and any possible implementation manner, there is further provided an implementation manner, wherein the apparatus further includes: The intelligent measurement and control module is used to receive and process the current and voltage detection data from the high voltage side or the low voltage side, and based on the current and voltage detection data of the high voltage side or the low voltage side, automatically control the contact action of the mechanical locking self-holding vacuum contactor to complete the tap winding switching.

[0007] According to the above aspects and any possible implementation, an implementation is further provided, when it is necessary to connect the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are closed, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K11, K12) are disconnected, and the mechanical locking self-holding vacuum contactor contacts (K21, K22) are closed, and the first group of primary tap windings (A2, B2, C2) are connected in series with the primary main winding; After the tap windings (A2, B2, C2) have been correctly connected, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are disconnected, and the transition impedance Z1 is exited.

[0008] According to the above aspects and any possible implementation, an implementation is further provided, when it is necessary to exit the primary tap winding (A2, B2, C2), the mechanically locked self-holding vacuum contactor contacts (11 in K, 12 in K) are closed, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K21, K22) are disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Control the mechanical locking self-holding vacuum contactor contacts (K11, K12) to close and restore the normal connection of the primary main winding; After the tap winding (A2, B2, C2) has been withdrawn, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are disconnected, and the transition impedance Z1 is withdrawn.

[0009] According to the above aspects and any possible implementation, an implementation is further provided, wherein the device is disposed in a fully enclosed metal shell, and the metal shell is filled with pure dry nitrogen gas maintaining a positive pressure.

[0010] According to a second aspect of the present disclosure, a method for intelligent control of on-load voltage regulation of a distribution transformer is provided. Based on any of the above on-load voltage regulation devices for the distribution transformer, the method comprises: Receive current and voltage detection data from the high voltage side or low voltage side through the intelligent measurement and control module; Determine the required voltage adjustment based on the test data and select the corresponding tap winding; According to the selected tap winding, the intelligent measurement and control module controls the connection or exit of the corresponding transition impedance, and controls the corresponding vacuum contactor contact action to complete the switching of the tap winding.

[0011] According to the above aspects and any possible implementation, an implementation is further provided, which controls the access of the corresponding transition impedance through the intelligent measurement and control module according to the selected tap winding, and controls the corresponding vacuum contactor contact action to complete the switching of the tap winding, including: If it is necessary to connect the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are controlled to close, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the mechanical locking self-holding vacuum contactor contacts (K21, K22) are closed, and the first group of primary tap windings (A2, B2, C2) are connected in series with the primary main winding; After the tap windings (A2, B2, C2) have been correctly connected, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the transition impedance Z1 is exited.

[0012] According to the above aspects and any possible implementation, an implementation is further provided, wherein according to the selected tap winding, the corresponding transition impedance is controlled to exit through the intelligent measurement and control module, and the corresponding vacuum contactor contact action is controlled to complete the switching of the tap winding, including: If it is necessary to exit the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are controlled to close, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K21, K22) are controlled to be disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Control the mechanical locking self-holding vacuum contactor contacts (K11, K12) to close and restore the normal connection of the primary main winding; After the tap winding (A2, B2, C2) has been withdrawn, when the current transformer L12 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the transition impedance Z1 is withdrawn. According to a third aspect of the present disclosure, an electronic device is provided, comprising: a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the program, the method according to the second aspect of the present disclosure is implemented.

[0013] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the method according to the second aspect of the present disclosure is implemented.

[0014] Compared with the prior art, the present invention achieves the following beneficial effects: (1) Through the coordination of intelligent measurement and control devices and transition impedance, the tap winding can be selected to be connected or disconnected for voltage regulation without power outage, avoiding short-term power outages that may occur during traditional voltage regulation and improving the continuity and stability of power supply. The transition impedance is used to limit the current to ensure that no electrical short circuit occurs, thereby protecting the safety of equipment and the power grid.

[0015] (2) The voltage regulation process must be carried out step by step, and cross-level regulation is not allowed. This allows the voltage to be adjusted gradually, reducing the impact on the power grid and equipment and extending the service life of the equipment.

[0016] (3) The on-load voltage regulator of the distribution transformer is placed in a fully enclosed metal cabinet, and the cabinet is filled with pure, dry nitrogen at positive pressure, which effectively prevents the entry of external dust and moisture, thereby improving the insulation performance and environmental adaptability of the device.

[0017] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, among which: Figure 1 A schematic diagram of the principle of a star-connected on-load voltage regulator on the primary side of a distribution transformer according to an embodiment of the present disclosure is shown; Figure 2 A schematic diagram of the principle of an intelligent measurement and control device for on-load voltage regulation of a distribution transformer according to an embodiment of the present disclosure is shown; Figure 3 A schematic diagram of the principle of a single-phase on-load voltage regulating device with triangle connection on the primary side of a distribution transformer according to an embodiment of the present disclosure is shown; Among them, 1: distribution transformer primary main winding (A1, B1, C1), 2: distribution transformer primary tap winding (A2, B2, C2), 3: distribution transformer primary tap winding (A3, B3, C3), 4: primary main winding neutral point mechanical locking self-holding vacuum contactor contact (K11, K12), 5: primary tap winding 2 neutral point mechanical locking self-holding vacuum contactor contact (K21, K22), 6: primary tap winding 3 neutral point mechanical locking self-holding vacuum contactor contact (K31, K32), 7: transition impedance Z neutral point mechanical locking self-holding vacuum contactor contact (K11, K12 ), 8: transition impedance Z neutral point mechanical locking self-holding vacuum contactor contact (K21, K22), 9: transition impedance (Z1, Z2), L10: transition impedance (Z1, Z2) current transformer, L11: distribution transformer primary main winding (A1, B1, C1) current transformer, L12: distribution transformer primary tap winding (A2, B2, C2) current transformer. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0020] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0021] In view of the problem that the off-load voltage regulation of the existing public distribution transformer will cause short-term power outages for users, and the limited distribution operation and maintenance personnel are unable to meet the timely voltage regulation needs of the public distribution transformer, etc. The present invention provides a distribution transformer on-load voltage regulation device. Through the cooperation of the intelligent measurement and control device and the transition impedance, the tap winding can be selected to be connected or exited for voltage regulation without power outage, avoiding the short-term power outage that may occur in the traditional voltage regulation process, and improving the continuity and stability of power supply. The current is limited by the transition impedance to ensure that no electrical short circuit occurs, thereby protecting the safety of equipment and power grid.

[0022] In the following, in conjunction with the accompanying drawings, an on-load voltage regulating device for a distribution transformer and an intelligent voltage regulating control method provided by the present invention are described.

[0023] Embodiment 1 like Figure 1-Figure 2 As shown, a distribution transformer on-load voltage regulating device comprises: Distribution transformer primary main winding (A1, B1, C1); At least two groups of distribution transformer primary tap windings, including a first group of primary tap windings (A2, B2, C2) and a second group of primary tap windings (A3, B3, C3); Mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of the primary main winding of the distribution transformer; Mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of the first set of primary tap windings; Mechanically locked self-holding vacuum contactor contacts (K31, K32) connected to the neutral point of the second set of primary tap windings; At least two groups of transition impedances (Z1, Z2), including a first group of transition impedances Z1 and a second group of transition impedances Z2; mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of transition impedance Z1; mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of transition impedance Z2; The transition impedance (Z1, Z2) current transformer L10, the distribution transformer primary main winding (A1, B1, C1) current transformer L11, and the distribution transformer primary tap winding (A2, B2, C2) current transformer L12 are used to detect the current passing through each contact.

[0024] In some embodiments, the first group of transition impedances Z1 is associated with the first group of primary tap windings (A2, B2, C2), and the second group of transition impedances Z2 is associated with the second group of primary tap windings (A3, B3, C3), and each group of transition impedances is connected to the circuit through a corresponding mechanically locked self-holding vacuum contactor contact, wherein the first group of transition impedances Z1 and the second group of transition impedances Z2 are configured with a total of 6 groups of equal transition impedances.

[0025] In some embodiments, the on-load voltage regulating device of the distribution transformer also includes an intelligent measurement and control module, which is used to receive and process current and voltage detection data from the high-voltage side or the low-voltage side, and based on the current and voltage detection data of the high-voltage side or the low-voltage side, automatically controls the movement of the mechanically locked self-holding vacuum contactor contacts to complete the tap winding switching.

[0026] In some embodiments, Figure 3 As shown, in order to intuitively illustrate the patented technology of the present invention, the secondary winding of the distribution transformer is not mentioned. The primary side delta connection voltage regulation method has the same principle as the star connection voltage regulation method, ensuring that no electrical short circuit occurs when the tap winding is connected or exited, and no distribution transformer is adjusted to cause a short-term power outage to the user.

[0027] The following will specifically introduce the gear adjustment method of connecting the primary tap windings A2, B2, C2 of the distribution transformer in series without power outage on the primary main windings A1, B1, C1 of the distribution transformer.

[0028] Regardless of whether it is through remote or local or on-load voltage regulation intelligent measurement and control device of distribution transformer, automatic intelligent non-stop power supply adjustment is implemented through the input of real-time data of current and voltage detection on the high-voltage or low-voltage side of the distribution transformer.

[0029] Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1In the process, the three groups of equivalent transition impedance Z1 neutral point mechanical locking self-holding vacuum contactor contacts K11 and K12 are closed at the same time, and the three groups of equivalent transition impedance Z1 are connected to the distribution transformer. At the same time, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are mechanically locked and self-held, and the three groups of equivalent transition impedance Z1 are connected to the state, and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the transition impedance Z1 is correctly connected, Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding exit of the mechanical locking self-holding vacuum contactor contacts K11 and K12. Figure 1 When the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are controlled to be disconnected, and the primary tap windings A2, B2, and C2 of the distribution transformer are connected in series with the primary main windings A1, B1, and C1. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K21 and K22 to be energized at the same time. Figure 1 In the process, the corresponding mechanical locking self-holding vacuum contactor contacts K21 and K22 are closed for mechanical locking self-holding, and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K21 and K22 is sent to the on-load voltage regulation intelligent measurement and control device; After the tap windings A2, B2, and C2 have been correctly connected, Figure 1 In the circuit, the primary tap winding A2, B2, C2 and three groups of equal transition impedances Z1 form a loop. The three groups of equal transition impedances Z1 limit the current flowing through the primary tap winding A2, B2, C2. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding vacuum contactor contacts K11 and K12 to exit the mechanical locking self-holding. Figure 1 In the process, when the current transformer L10 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11 and K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are controlled to be disconnected, and the three groups of equivalent transition impedances Z1 withdraw. The primary voltage of the distribution transformer is changed from being added to the primary main winding A1, B1, C1 winding to being added to the primary main winding A1, B1, C1 winding and the primary tap winding A2, B2, C2 winding, thereby realizing non-stop voltage regulation.

[0030] Without power outage, the adjustment method of serially inserting the primary tap windings A3, B3, and C3 is the same as above. The method of serially inserting more primary tap winding gears is still implemented one by one in the same way.

[0031] The following will specifically introduce the gear adjustment method of the primary tap windings A2, B2, and C2 of the distribution transformer when it exits the distribution transformer.

[0032] Specifically, automatic intelligent non-stop power supply adjustment is implemented by inputting real-time data of current and voltage detection on the high-voltage or low-voltage side of the distribution transformer, whether remotely or locally or through the on-load voltage regulation intelligent measurement and control device of the distribution transformer.

[0033] Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1 In the process, the neutral point mechanical locking self-holding vacuum contactor contacts K11 and K12 of the three groups of equivalent transition impedance Z1 are closed at the same time, and the three groups of equivalent transition impedance Z1 are connected to the distribution transformer. At the same time, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are mechanically locked and self-held, and the three groups of equivalent transition impedance Z1 are connected to the state, and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the transition impedance is correctly connected, Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding exit of the mechanical locking self-holding vacuum contactor contacts K21 and K22. Figure 1 In the process, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K21 and K22 are controlled to be disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1 In the process, the corresponding mechanical locking self-holding vacuum contactor contacts K11 and K12 are closed for mechanical locking and self-holding, and the normal connection of the primary main winding is restored; and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the tap windings A2, B2, and C2 have been withdrawn, Figure 1 In the circuit, the primary tap winding A2, B2, C2 and three groups of equal transition impedances Z1 form a loop. The three groups of equal transition impedances Z1 limit the current flowing through the primary tap winding A2, B2, C2. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding vacuum contactor contacts K11 and K12 to exit the mechanical locking self-holding. Figure 1When the current transformer L12 detects the zero crossing of the current of the mechanically locked self-holding vacuum contactor contacts (K21, K22), it controls the disconnection of the contacts K11 and K12 in the mechanically locked self-holding vacuum contactor K. The 3 groups of equivalent transition impedances Z1 are withdrawn, and the primary tap windings A2, B2, C2 of the distribution transformer are withdrawn from the primary main windings A1, B1, C1. The primary voltage of the distribution transformer is changed from being originally applied to the primary main windings A1, B1, C1 and the primary tap windings A2, B2, C2 to being applied to the primary main windings A1, B1, C1, realizing voltage regulation without power interruption.

[0034] The method of shifting gears for withdrawing the primary tap windings A3, B3, C3 without power interruption is the same as above. For the method of withdrawing more primary tap winding gears, it is still implemented one by one in the same way.

[0035] In some embodiments, current transformers L10 for the transition impedances (Z1, Z2), current transformers L11 for the primary main windings (A1, B1, C1) of the distribution transformer, and current transformers L12 for the primary tap windings (A2, B2, C2) of the distribution transformer are all built into the on-load voltage regulating intelligent measurement and control device of the distribution transformer, and are respectively used to detect the currents passing through the mechanically locked self-holding vacuum contactor contacts (K11, K12) at the neutral point of the primary main winding, the mechanically locked self-holding vacuum contactor contacts (K21, K22, K31, K32) at the neutral point of the primary tap winding, and the mechanically locked self-holding vacuum contactor contacts (K11, K12, K21, K22) at the neutral point of the transition impedance Z.

[0036] In some embodiments, the adjustment of the distribution transformer gear must follow the step-by-step connection or withdrawal of the primary tap winding one by one, and cannot skip gears. For example, when operating from gear 1 to gear 3, it must be from gear 1 to gear 2, and then from gear 2 to gear 3. It is not allowed to directly go from gear 1 to gear 3.

[0037] It should be emphasized that the device needs to be completely placed in a fully enclosed metal casing. The fully enclosed metal casing needs to be filled with pure and dry nitrogen with positive pressure. The primary high-voltage incoming line and the connection lead-out line of the tap winding inside the distribution transformer are connected through the fully sealed terminal studs on the metal cabinet casing of the on-load intelligent voltage regulating device of the distribution transformer. In this way, the high-voltage insulation requirements of the on-load intelligent voltage regulating device of the distribution transformer are met. The mechanically locked self-holding vacuum contactor inside the on-load intelligent voltage regulating device of the distribution transformer solves the problems of arc extinguishing during the opening and closing of the operating contacts of the gear shifting mechanism and the requirement that the contactor remains in the closed position when the control coil of the vacuum contactor is powered off through mechanical locking and self-holding.

[0038] According to the embodiments of the present disclosure, the following technical effects are achieved: (1) Through the coordination of intelligent measurement and control devices and transition impedance, the tap winding can be selected to be connected or disconnected for voltage regulation without power outage, avoiding short-term power outages that may occur during traditional voltage regulation and improving the continuity and stability of power supply. The transition impedance is used to limit the current to ensure that no electrical short circuit occurs, thereby protecting the safety of equipment and the power grid.

[0039] (2) The voltage regulation process must be carried out step by step, and cross-level regulation is not allowed. This allows the voltage to be adjusted gradually, reducing the impact on the power grid and equipment and extending the service life of the equipment.

[0040] (3) The on-load voltage regulator of the distribution transformer is placed in a fully enclosed metal cabinet, and the cabinet is filled with pure, dry nitrogen at positive pressure, which effectively prevents the entry of external dust and moisture, thereby improving the insulation performance and environmental adaptability of the device.

[0041] Embodiment 2 This embodiment provides an intelligent control method for on-load voltage regulation of a distribution transformer, based on the on-load voltage regulation device of the distribution transformer as described in Embodiment 1, and characterized by comprising: The current and voltage detection data from the high voltage side or the low voltage side are received through the intelligent measurement and control module; the required voltage adjustment is determined based on the detection data, and the corresponding tap winding is selected; based on the selected tap winding, the intelligent measurement and control module controls the connection or exit of the corresponding transition impedance, and controls the corresponding vacuum contactor contact action to complete the switching of the tap winding.

[0042] The following will specifically introduce the gear adjustment method of connecting the primary tap windings A2, B2, C2 of the distribution transformer in series without power outage on the primary main windings A1, B1, C1 of the distribution transformer.

[0043] Regardless of whether it is through remote or local or on-load voltage regulation intelligent measurement and control device of distribution transformer, automatic intelligent non-stop power supply adjustment is implemented through the input of real-time data of current and voltage detection on the high-voltage or low-voltage side of the distribution transformer.

[0044] Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1 In the process, the three groups of equivalent transition impedance Z1 neutral point mechanical locking self-holding vacuum contactor contacts K11 and K12 are closed at the same time, and the three groups of equivalent transition impedance Z1 are connected to the distribution transformer. At the same time, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are mechanically locked and self-held, and the three groups of equivalent transition impedance Z1 are connected to the state, and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the transition impedance Z1 is correctly connected, Figure 2In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding exit of the mechanical locking self-holding vacuum contactor contacts K11 and K12. Figure 1 When the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are controlled to be disconnected, and the primary tap windings A2, B2, and C2 of the distribution transformer are connected in series with the primary main windings A1, B1, and C1. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K21 and K22 to be energized at the same time. Figure 1 In the process, the corresponding mechanical locking self-holding vacuum contactor contacts K21 and K22 are closed for mechanical locking self-holding, and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K21 and K22 is sent to the on-load voltage regulation intelligent measurement and control device; After the tap windings A2, B2, and C2 have been correctly connected, Figure 1 In the circuit, the primary tap winding A2, B2, C2 and three groups of equal transition impedances Z1 form a loop. The three groups of equal transition impedances Z1 limit the current flowing through the primary tap winding A2, B2, C2. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding vacuum contactor contacts K11 and K12 to exit the mechanical locking self-holding. Figure 1 In the process, when the current transformer L10 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are controlled to be disconnected, and the three groups of equivalent transition impedances Z exit. The primary voltage of the distribution transformer is changed from being added to the primary main winding A1, B1, C1 winding to being added to the primary main winding A1, B1, C1 winding and the primary tap winding A2, B2, C2 winding, thereby realizing non-stop voltage regulation.

[0045] Without power outage, the adjustment method of serially inserting the primary tap windings A3, B3, and C3 is the same as above. The method of serially inserting more primary tap winding gears is still implemented one by one in the same way.

[0046] The following will specifically introduce the gear adjustment method of the primary tap windings A2, B2, and C2 of the distribution transformer when it exits the distribution transformer.

[0047] Specifically, automatic intelligent non-stop power supply adjustment is implemented by inputting real-time data of current and voltage detection on the high-voltage or low-voltage side of the distribution transformer, whether remotely or locally or through the on-load voltage regulation intelligent measurement and control device of the distribution transformer.

[0048] Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1 In the process, 3 groups of equivalent transition impedance Z neutral point mechanical locking self-holding vacuum contactor contacts K11 and K12 are closed at the same time, 3 groups of equivalent transition impedance Z1 are connected to the distribution transformer, and at the same time, mechanical locking self-holding vacuum contactor contacts K11 and K12 are mechanically locked and self-held, 3 groups of equivalent transition impedance Z1 are connected, and the mechanical locking self-holding state switch quantity of mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the transition impedance Z1 is correctly connected, Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding exit of the mechanical locking self-holding vacuum contactor contacts K21 and K22. Figure 1 In the process, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K21 and K22 are controlled to be disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the control coils of the mechanical locking self-holding vacuum contactors K11 and K12 to be energized at the same time. Figure 1 In the process, the corresponding mechanical locking self-holding vacuum contactor contacts K11 and K12 are closed for mechanical locking and self-holding, and the normal connection of the primary main winding is restored; and the mechanical locking self-holding state switch quantity of the mechanical locking self-holding vacuum contactor contacts K11 and K12 is sent to the on-load voltage regulation intelligent measurement and control device; After the tap windings A2, B2, and C2 have been withdrawn, Figure 1 In the circuit, the primary tap windings A2, B2, and C2 form a loop with three groups of equal transition impedances Z. The three groups of equal transition impedances Z limit the current flowing through the primary tap windings A2, B2, and C2. Figure 2 In the process, the on-load voltage regulation intelligent measurement and control device controls the mechanical locking self-holding vacuum contactor contacts K11 and K12 to exit the mechanical locking self-holding. Figure 1 In the process, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts K11 and K12 are controlled to be disconnected, and the three groups of equivalent transition impedances Z1 withdraw. The primary tap winding A2, B2, and C2 windings of the distribution transformer withdraw from the primary main winding A1, B1, and C1 windings. The primary voltage of the distribution transformer is changed from being added to the primary main winding A1, B1, and C1 windings and the primary tap winding A2, B2, and C2 windings to being added to the primary main winding A1, B1, and C1 windings, thereby realizing non-stop voltage regulation.

[0049] The method for adjusting the gears of the primary tap windings A3, B3, and C3 without power outage is the same as above. The method for exiting more primary tap winding gears is still implemented one by one in the same way.

[0050] In some embodiments, the gear adjustment of the distribution transformer must comply with the step-by-step connection or withdrawal of the primary tap winding, and the gear adjustment cannot be made across gears. For example, the operation of adjusting from gear 1 to gear 3 must be from gear 1 to gear 2, and then from gear 2 to gear 3, and it cannot be adjusted directly from gear 1 to gear 3.

[0051] According to the embodiments of the present disclosure, the following technical effects are achieved: (1) Through the coordination of intelligent measurement and control devices and transition impedance, the tap winding can be selected to be connected or disconnected for voltage regulation without power outage, avoiding short-term power outages that may occur during traditional voltage regulation and improving the continuity and stability of power supply. The transition impedance is used to limit the current to ensure that no electrical short circuit occurs, thereby protecting the safety of equipment and the power grid.

[0052] (2) The voltage regulation process must be carried out step by step, and cross-level regulation is not allowed. This allows the voltage to be adjusted gradually, reducing the impact on the power grid and equipment and extending the service life of the equipment.

[0053] (3) The on-load voltage regulator of the distribution transformer is placed in a fully enclosed metal cabinet, and the cabinet is filled with pure, dry nitrogen at positive pressure, which effectively prevents the entry of external dust and moisture, thereby improving the insulation performance and environmental adaptability of the device.

[0054] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present disclosure is not limited by the described order of actions, because according to the present disclosure, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present disclosure.

[0055] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0056] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of this disclosure can be achieved, and this document is not limited here.

[0057] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A distribution transformer on-load voltage regulating device, characterized in that: include: Distribution transformer primary main winding (A1, B1, C1); At least two groups of distribution transformer primary tap windings, including a first group of primary tap windings (A2, B2, C2) and a second group of primary tap windings (A3, B3, C3); Mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of the primary main winding of the distribution transformer; Mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of the first set of primary tap windings; Mechanically locked self-holding vacuum contactor contacts (K31, K32) connected to the neutral point of the second set of primary tap windings; At least two groups of transition impedances (Z1, Z2), including a first group of transition impedances Z1 and a second group of transition impedances Z2; mechanically locked self-holding vacuum contactor contacts (K11, K12) connected to the neutral point of transition impedance Z1; mechanically locked self-holding vacuum contactor contacts (K21, K22) connected to the neutral point of transition impedance Z2; Each transformer winding and transition impedance is equipped with a corresponding current transformer to detect the current passing through each contact. When the current of each contact is detected to pass through the zero point, the corresponding mechanical locking self-holding vacuum contactor contact is disconnected.

2. The device according to claim 1, characterized in that The first group of transition impedances Z1 is associated with the first group of primary tap windings (A2, B2, C2), the second group of transition impedances Z2 is associated with the second group of primary tap windings (A3, B3, C3), and each group of transition impedances is connected to the circuit through a corresponding mechanically locked self-holding vacuum contactor contact.

3. The device according to claim 1, characterized in that The first group of transition impedances Z1 and the second group of transition impedances Z2 are both equal-value impedances.

4. The device according to claim 1, characterized in that The device also includes: The intelligent measurement and control module is used to receive and process the current and voltage detection data from the high voltage side or the low voltage side, and based on the current and voltage detection data of the high voltage side or the low voltage side, automatically control the contact action of the mechanical locking self-holding vacuum contactor to complete the tap winding switching.

5. The device according to claim 4, characterized in that When it is necessary to connect the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are closed, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K11, K12) are disconnected, and the mechanical locking self-holding vacuum contactor contacts (K21, K22) are closed, and the first group of primary tap windings (A2, B2, C2) are connected in series with the primary main winding; After the tap windings (A2, B2, C2) have been correctly connected, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are disconnected, and the transition impedance Z1 is exited.

6. The device according to claim 4, characterized in that When it is necessary to exit the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are closed, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K21, K22) are disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Control the mechanical locking self-holding vacuum contactor contacts (K11, K12) to close and restore the normal connection of the primary main winding; After the tap winding (A2, B2, C2) has been withdrawn, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are disconnected, and the transition impedance Z1 is withdrawn.

7. The device according to claim 1, characterized in that The device is arranged in a fully enclosed metal shell, and the metal shell is filled with pure dry nitrogen gas maintaining a positive pressure.

8. An intelligent control method for on-load voltage regulation of a distribution transformer, based on the on-load voltage regulation device of a distribution transformer as claimed in any one of claims 1 to 4, characterized in that: include: Receive current and voltage detection data from the high voltage side or low voltage side through the intelligent measurement and control module; Determine the required voltage adjustment based on the test data and select the corresponding tap winding; According to the selected tap winding, the intelligent measurement and control module controls the connection or exit of the corresponding transition impedance, and controls the corresponding vacuum contactor contact action to complete the switching of the tap winding.

9. The method according to claim 8, characterized in that According to the selected tap winding, the intelligent measurement and control module controls the access of the corresponding transition impedance and the corresponding vacuum contactor contact action to complete the switching of the tap winding, including: If it is necessary to connect the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are controlled to close, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L11 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the mechanical locking self-holding vacuum contactor contacts (K21, K22) are closed, and the first group of primary tap windings (A2, B2, C2) are connected in series with the primary main winding; After the tap windings (A2, B2, C2) have been correctly connected, when the current transformer L10 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K11, K12) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the transition impedance Z1 is exited.

10. The method according to claim 9, characterized in that According to the selected tap winding, the corresponding transition impedance is controlled to exit through the intelligent measurement and control module, and the corresponding vacuum contactor contact action is controlled to complete the switching of the tap winding, including: If it is necessary to exit the primary tap winding (A2, B2, C2), the mechanical locking self-holding vacuum contactor contacts (11 in K, 12 in K) are controlled to close, and the transition impedance Z1 is connected to the circuit; After the transition impedance Z1 is correctly connected, when the current transformer L12 detects that the current of the mechanical locking self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanical locking self-holding vacuum contactor contacts (K21, K22) are controlled to be disconnected, so that the primary tap winding (A2, B2, C2) is separated from the primary main winding; Control the mechanical locking self-holding vacuum contactor contacts (K11, K12) to close and restore the normal connection of the primary main winding; After the tap winding (A2, B2, C2) has been withdrawn, when the current transformer L12 detects that the current of the mechanically locked self-holding vacuum contactor contacts (K21, K22) passes through the zero point, the mechanically locked self-holding vacuum contactor contacts (K11, K12) are controlled to be disconnected, and the transition impedance Z1 is withdrawn.

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