Long-line mechanical-electronic combined type voltage regulating system and long-line mechanical-electronic combined type voltage regulating method
By combining mechanical and electronic voltage regulating modules, the fire hazards and high costs of long-line voltage regulating devices have been solved, achieving continuous real-time voltage regulation and efficient voltage adjustment, thereby reducing equipment costs and defect rates.
Patent Information
- Application Number
- CN202511406478.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-29
- Publication Date
- 2026-02-10
AI Technical Summary
Existing voltage regulating devices pose fire hazards, high costs, and high defect rates in long lines. In particular, oil-immersed voltage regulating devices are prone to fires, while power electronic voltage regulating devices are expensive and cannot be maintained by shutting down power on one side.
By combining mechanical and electronic voltage regulating modules, the mechanical module performs a large-scale coarse adjustment, and the electronic module makes up the voltage difference in real time, forming continuous real-time voltage regulation, which reduces equipment costs and defect rate.
It achieves continuous real-time voltage regulation, reduces equipment costs and defect rates, avoids the inherent defects of a single voltage regulation module, and improves system reliability and power quality.
Smart Images
Figure CN121507801A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of power grid voltage regulation technology, and in particular to a long-line electromechanical combined voltage regulation system and method. Background Technology
[0002] In related technologies, 10kV long power distribution lines exceeding 15km in remote areas have always been a challenge for power grid configuration. These lines suffer from several issues: severe overvoltage during low-load periods, severe undervoltage during high-load periods (with phase differences exceeding 100V), and situations where small hydropower and other green energy sources generate high voltage at full capacity but low voltage at no capacity. Constructing a dedicated 110kV or 35kV substation for this purpose would result in significant investment and wasted capacity.
[0003] For situations where the total capacity is insufficient for the deployment of substations, single-line length exceeds 15km, and total load does not exceed 10MVA, relevant technologies propose a series-connected line voltage regulating device to adjust the voltage regulation at the mid-to-back end, achieving an overall intermediate voltage support method. This method involves shifting the substation bus voltage by 10km for bidirectional regulation, thereby eliminating low / high voltage issues at the end. Intermediate voltage support is the most economical and efficient solution, implementing a wide-range voltage regulation method and load guarantee measures. Combined with primary and secondary system implementation plans, it solves the problems of large voltage fluctuations in remote areas and other E and F class load areas, and the lack of profitability for power grid investment in high-voltage level substations.
[0004] Among the existing voltage regulation schemes for series-connected line voltage regulating devices, there are two main options: oil-immersed series on-load tap changer scheme and power electronic voltage regulating scheme. However, the oil-immersed series on-load tap changer scheme has the following problems: 1. In remote areas, if an oil-immersed device fails, the Class A insulation heat resistance level is highly susceptible to deflagration, which can cause wildfires in remote areas. These fires can continue to burn, and due to the long arrival time of firefighters, secondary disasters can escalate significantly, further increasing losses and impacts. 2. The voltage regulator relies on overload protection, which requires a significant increase in inter-turn short circuits before tripping. Since oil-immersed voltage regulators primarily handle current flow and cannot employ inverse-time protection, fires are highly likely to escalate into deflagration.
[0005] The power electronic voltage regulating scheme has the following problems: 1. If any equipment in the primary or secondary control fails, the electronic voltage regulating system will be locked, and the entire system must be taken out of service. 2. The cost is twice that of the oil-immersed series on-load tap changer scheme. 3. It cannot be used for maintenance with power outages on one side only. Summary of the Invention
[0006] The technical problem to be solved by the present invention is to provide a long-line electromechanical combined voltage regulation system to solve the problems of fire hazards, high cost and high defect rate of existing voltage regulation systems.
[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A long-line mechanical-electronic combined voltage regulation system includes a mechanical voltage regulation module and an electronic voltage regulation module; the first end of the mechanical voltage regulation module is used to connect to the high-voltage line of the power grid; the second end of the mechanical voltage regulation module is connected to the first end of the electronic voltage regulation module; the second end of the electronic voltage regulation module is used to connect to a transformer; the electronic voltage regulation module is used to compensate for the jump voltage difference formed by the voltage regulation of the mechanical voltage regulation module after the mechanical voltage regulation module performs voltage adjustment.
[0008] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is as follows: A long-line electromechanical combined voltage regulation method is applied to a long-line electromechanical combined voltage regulation system as described above. The method includes: receiving a voltage adjustment command, controlling the mechanical voltage regulation module to perform coarse voltage adjustment, and controlling the electronic voltage regulation module to compensate for the jump voltage difference formed by the voltage adjustment of the mechanical voltage regulation module.
[0009] The beneficial effects of this invention are as follows: It employs a scheme where a mechanical voltage regulating module and an electronic voltage regulating module are connected in series in the circuit. After the mechanical voltage regulating module performs a large-range coarse adjustment, the electronic voltage regulating module then compensates for the remaining voltage difference in real time, forming continuous real-time voltage regulation. This solves the inherent defects of voltage regulation by a single mechanical voltage regulating module. The electronic voltage regulating module is only used to adjust the voltage difference between a single range and the standard required voltage. Therefore, compared to existing all-electronic voltage regulation schemes, it does not need to consider the compensation capacity and insulation strength across the entire voltage range, greatly reducing equipment costs. This also solves the problems of high cost, high defect rate, and the need to forcibly remove the entire voltage regulating device due to secondary control defects in existing electronic voltage regulation systems. Attached Figure Description
[0010] Figure 1 This is a schematic diagram illustrating the application of a long-line electromechanical combined voltage regulation system at the online end in an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the application of a long-line electromechanical combined voltage regulation system on the center point side in an embodiment of the present invention; Label Explanation: 1. Mechanical voltage regulating module; 2. Electronic voltage regulating module; 3. Fine-tuning voltage injection transformer; AH1, high-voltage incoming switchgear; AH2, high-voltage bypass switchgear; AH3, high-voltage outgoing switchgear. Detailed Implementation
[0011] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.
[0012] In related technologies, voltage regulation schemes for the downstream voltage regulation of series-connected line voltage regulators include: oil-immersed series on-load tap changer schemes and power electronic voltage regulation schemes. Especially for power electronic voltage regulation schemes, fully electronic voltage regulation requires stacking electronic components such as thyristors or IGBTs (Insulated Gate Bipolar Transistors) to meet all compensation capacities and insulation strength requirements. Typically, the tap increments of on-load tap changers in distribution networks are 0-2.5%-5%. Taking a 2.5% increment as an example, one set of related electronic components is required. If the voltage regulation is ±15%, at least six sets of ±2.5% related electronic components need to be stacked to meet the 30% total capacity between the limit increments, i.e., 30% of the entire line's voltage regulation capacity. This, combined with the voltage difference between the 30% limit increments, and the basic insulation requirements for the series winding position (rated voltage to ground 10kV and withstand voltage level 42kV), leads to a significant increase in cost.
[0013] To solve the above-mentioned technical problems, the present invention provides a long-line electromechanical combined voltage regulation system, as follows: A long-line mechanical-electronic combined voltage regulation system includes a mechanical voltage regulation module and an electronic voltage regulation module; the first end of the mechanical voltage regulation module is used to connect to the high-voltage line of the power grid; the second end of the mechanical voltage regulation module is connected to the first end of the electronic voltage regulation module; the second end of the electronic voltage regulation module is used to connect to a transformer; the electronic voltage regulation module is used to compensate for the jump voltage difference formed by the voltage regulation of the mechanical voltage regulation module after the mechanical voltage regulation module performs voltage adjustment.
[0014] As can be seen from the above description, the beneficial effects of the present invention are as follows: It employs a scheme in which a mechanical voltage regulating module and an electronic voltage regulating module are connected in series in the circuit. After the mechanical voltage regulating module performs a large-range coarse adjustment, the electronic voltage regulating module then compensates for the remaining voltage difference in real time, forming continuous real-time (millisecond-level delay) voltage regulation. This solves the inherent defects of voltage regulation by a single mechanical voltage regulating module. The electronic voltage regulating module is only used to adjust the voltage difference between a single range and the standard required voltage. Therefore, compared to existing all-electronic voltage regulation schemes, it does not need to consider the compensation capacity and insulation strength of the entire voltage range, greatly reducing equipment costs. This solves the problems of high cost, high defect rate, and the need to forcibly remove the entire voltage regulating device due to secondary control defects in existing electronic voltage regulation.
[0015] Furthermore, it also includes a fine-tuning voltage injection transformer; the fine-tuning voltage injection transformer is connected in series between the mechanical voltage regulating module and the electronic voltage regulating module; or the fine-tuning voltage injection transformer is connected in series between the mechanical voltage regulating module and the high-voltage line of the power grid.
[0016] As described above, by placing the fine-tuning voltage injection transformer between the mechanical voltage regulating module and the electronic voltage regulating module, the long-line mechanical and electronic combined voltage regulating system can be applied to the neutral point side scenario; while by connecting the fine-tuning voltage injection transformer in series between the mechanical voltage regulating module and the high-voltage line of the power grid, the long-line mechanical and electronic combined voltage regulating system can be applied to the line end scenario; thus meeting the usage requirements of different scenarios.
[0017] Furthermore, the mechanical voltage regulating module includes at least two different voltage levels, with adjacent voltage levels forming a level difference; the number of electronic components in the electronic voltage regulating module corresponds to the level difference.
[0018] As described above, by setting the number of electronic components in the electronic voltage regulator module to correspond to the first-level voltage difference, i.e., the electronic voltage regulator module is mainly used to make up for the first-level voltage difference, the number of electronic components in the electronic voltage regulator module can be greatly reduced compared to the existing all-electronic voltage regulation scheme, thereby reducing costs.
[0019] Furthermore, the electronic voltage regulation module includes a main thyristor and electronic control components.
[0020] As described above, the electronic voltage regulation module consists of a main thyristor and electronic control components. The electronic control components control the switching of the main thyristor, thereby realizing the electronic voltage regulation function.
[0021] Furthermore, the electronic voltage regulating module includes an electronic three-level voltage regulator.
[0022] As can be seen from the above description, using an electronic three-level voltage regulator as the electronic voltage regulation module can achieve the requirement of high-precision voltage regulation.
[0023] Furthermore, the mechanical voltage regulating module includes a mechanical autotransformer.
[0024] As can be seen from the above description, using a mechanical autotransformer as a mechanical voltage regulation module can meet the needs of voltage regulation over a wide range.
[0025] Another embodiment of the present invention provides a long-line electromechanical combined voltage regulation method, applied to a long-line electromechanical combined voltage regulation system as described above, the method comprising: The system receives voltage adjustment instructions, controls the mechanical voltage adjustment module to perform coarse voltage adjustment, and controls the electronic voltage adjustment module to compensate for the jump voltage difference caused by the mechanical voltage adjustment module.
[0026] As described above, the voltage regulation method based on the combined mechanical and electronic voltage regulation system for long-line circuits can solve the problems existing when using a single mechanical voltage regulation module. Furthermore, during the control process, the mechanical voltage regulation module is first controlled to perform coarse adjustment, and then the electronic voltage regulation module is controlled to compensate for the jump voltage difference caused by the mechanical voltage regulation module, achieving selective coarse and fine voltage regulation and precisely controlling the tap or voltage difference of the series reactor in the line. Moreover, the combined voltage regulation method avoids the problems of the electronic secondary control failure requiring the voltage regulation device to be shut down, the inability to regulate voltage, the inability of the series reactor bypass and voltage regulation circuit to operate simultaneously, and the need for circuit power outage switching.
[0027] Furthermore, it also includes: if the adjustment command is to adjust the voltage difference by one level, then after controlling the mechanical voltage adjustment module to adjust the voltage difference by a preset ratio, controlling the electronic voltage adjustment module to make up the remaining voltage difference.
[0028] As can be seen from the above description, when the adjustment command is to adjust the voltage difference by one level, the mechanical voltage adjustment module is still the main voltage adjustment method, and the electronic voltage adjustment module makes up the remaining voltage difference, which can improve the efficiency of voltage regulation.
[0029] Furthermore, it also includes: if the adjustment command is to adjust at least two voltage levels, then the command to adjust the voltage level by one level is executed sequentially until the target voltage level is reached.
[0030] As can be seen from the above description, when the gear adjustment command is a multi-level adjustment, executing the command to adjust the voltage level one level at a time can avoid the voltage level jump and solve the problem of jump and discontinuity in multi-level voltage adjustment.
[0031] Furthermore, it also includes: if an abnormality is detected in the electronic voltage regulator module, the electronic voltage regulator module is short-circuited.
[0032] As described above, when an abnormality is detected in the electronic voltage regulator module, the mechanical voltage regulator module can still be used normally after the electronic voltage regulator module is short-circuited. Although the fine adjustment function is lost, the voltage adjustment can still be coarsely adjusted by step.
[0033] The mechanical-electronic combined voltage regulation system and method provided by this invention can be applied to voltage regulation scenarios for lines exceeding 15km in length. It employs a novel approach of coarse adjustment via on-load tap changers in the later stages of lines exceeding 15km in length, followed by fine adjustment via electronic active voltage converters. This combines the reliability of mechanical voltage regulation with the real-time performance of electronic voltage regulation, eliminating the tap difference inherent in mechanical regulation and the abnormal exit of electronic regulation. It achieves wide-range and high-precision line-side voltage regulation, solving the low-voltage problem at the rear of lines exceeding 15km in length, as well as the high-voltage, capacity limitations, and proximity interface issues after the integration of small hydropower, photovoltaic, and other distributed green energy sources. It eliminates the inefficient investment in frequent power outage tap changes, distributed voltage regulating distribution transformers, and centralized 35kV substations, improving operational reliability, power quality, and user experience. Specifically: Please refer to Figure 1 A long-line electromechanical combined voltage regulating system includes a mechanical voltage regulating module 1, an electronic voltage regulating module 2, and a fine-tuning voltage injection transformer 3. The first end of the mechanical voltage regulating module 1 is connected to the high-voltage line of the power grid. The second end of the mechanical voltage regulating module 1 is connected to the first end of the electronic voltage regulating module 2. The second end of the electronic voltage regulating module 2 is connected to the transformer. In this embodiment, the electronic voltage regulating module 2 includes an electronic three-level voltage regulator, and the mechanical voltage regulating module 1 includes a mechanical autotransformer. Figure 1 As shown, the transformer is a step-down transformer (station power supply), used to convert high voltage (10kV) to low voltage (0.4kV) and to enable local high voltage and low voltage green electricity access; the electronic voltage regulating module 2 is used to make up for the jump voltage difference formed by the voltage regulation of the mechanical voltage regulating module 1 after the mechanical voltage regulating module 1 performs the voltage adjustment.
[0034] like Figure 1 As shown, the fine-tuning voltage injection transformer 3 is connected in series between the mechanical voltage regulating module 1 and the high-voltage line of the power grid. That is, the fine-tuning voltage injection transformer 3, the mechanical voltage regulating module 1, and the electronic voltage regulating module 2 are connected in series in sequence. This is mainly used in line-end application scenarios, where line-end voltage regulation is equivalent to high-potential voltage regulation. The input terminals (A1, B1, and C1) of the fine-tuning voltage injection transformer 3 are connected to the high-voltage input side of the high-voltage line of the power grid, and the output terminals (A2, B2, and C2) of the fine-tuning voltage injection transformer 3 are connected to the high-voltage output side of the high-voltage line of the power grid. Among them, the high-voltage line of the power grid is equipped with a high-voltage input switch cabinet AH1, a high-voltage bypass switch cabinet AH2, and a high-voltage output switch cabinet AH3, which are used to realize the input, bypass, and output control, respectively. At the same time, because the high voltage at the line end requires the corresponding stacked semiconductor components to meet the insulation requirements, the cost reduction of electronic components is limited, there is no multi-point grounding problem, and there is no need to increase the diameter of the common winding of the autotransformer.
[0035] The mechanical voltage regulating module 1 includes at least two different voltage levels, with adjacent voltage levels forming a primary voltage level difference. The number of electronic components in the electronic voltage regulating module 2 corresponds to the primary voltage level difference. In related technologies, the voltage level difference for on-load tap changers in distribution networks is 2.5%-5%, and for the main grid it is 1.25%. Each voltage regulation is directly adjusted according to the level difference, inevitably resulting in jumps in the level difference. At the same time, fully electronic voltage regulation requires stacking all compensation capacity and insulation strength using electronic components such as thyristors or IGBTs. For example, if the voltage regulation is ±15%, then 2.5%*6 level difference capacity and differential voltage insulation need to be stacked. The primary components required for electronic voltage regulation are only 1 / 6 of those required for electronic voltage regulation, without considering insulation strength or secondary transformer issues. In this embodiment, the electronic three-level voltage regulator can output forward and reverse voltages, finely adjusting the voltage by 2.5%. By adding a millisecond-level response electronic voltage regulator, this 2.5% voltage step difference is completed. Fine adjustment only needs to achieve ±1.25% in both forward and reverse directions, or expand the margin to 1.5%. The electronic voltage regulator capacity only needs to be 1 / 2n (where n represents the voltage value of a single-level step difference), significantly reducing the number of electronic components. At the same time, the electronic voltage regulator module 2 can achieve millisecond-level adjustment, ensuring truly seamless voltage regulation. The adjustment voltage also increases from the series step difference of 2.5% or 5% to electronic real-time synchronous voltage regulation, reducing the theoretical accuracy range to below 0.1%, and actually setting it at 0.5%.
[0036] like Figure 2 As shown, the fine-tuning voltage injection transformer 3 is connected in series between the mechanical voltage regulating module 1 and the electronic voltage regulating module 2, that is, the mechanical voltage regulating module 1, the fine-tuning voltage injection transformer 3, and the electronic voltage regulating module 2 are connected in series. This is mainly used in neutral point side applications, where neutral point side voltage regulation is equivalent to zero-potential voltage regulation.
[0037] The mechanical voltage regulating module 1 is connected to the high-voltage incoming side of the power grid high-voltage line via its inlet terminals (A1, B1, and C1) and to the high-voltage outgoing side via its outlet terminals (A2, B2, and C2). The high-voltage line is equipped with a high-voltage incoming switchgear AH1, a high-voltage bypass switchgear AH2, and a high-voltage outgoing switchgear AH3, used for incoming, bypass, and outgoing line control, respectively. In this application scenario, a single-phase grounding problem occurs, meaning that some capacitive current cannot return to the substation's grounding point and may concentrate at the autotransformer, leading to a decrease in the reliability of the arc suppression coil. Therefore, the short-time current carrying capacity of the autotransformer's entire winding needs to be increased, from the original voltage-supported cross-section of 6mm² to 25mm².
[0038] Another embodiment of the present invention provides a long-line electromechanical combined voltage regulation method, applied to a long-line electromechanical combined voltage regulation system as described above, the method comprising: Upon receiving the voltage adjustment command, the system controls the mechanical voltage regulating module 1 to perform coarse voltage adjustment, and controls the electronic voltage regulating module 2 to compensate for the jump voltage difference caused by the voltage adjustment of the mechanical voltage regulating module 1. That is, in the control process, the mechanical voltage regulating module 1 is first controlled to perform coarse voltage adjustment, and then the electronic voltage regulating module 2 is controlled to compensate for the jump voltage difference caused by the voltage adjustment of the mechanical voltage regulating module 1, so as to achieve selective coarse and fine voltage regulation.
[0039] If the adjustment command is to adjust the voltage difference by one level, the mechanical voltage regulating module 1 will adjust the voltage difference by a preset ratio, and then the electronic voltage regulating module 2 will make up the remaining voltage difference. For example, if the voltage difference is 2.5%, the mechanical voltage regulating module 1 will adjust the voltage difference by about 2 / 3. When the corresponding percentage is executed, the voltage difference will be adjusted between 1.5-2% (excluding the electronic voltage regulation part). The remaining part, which is less than half a level difference, will be automatically made up by the electronic voltage regulating module 2 to ensure that the output is maintained at 10.5kV.
[0040] If the voltage adjustment command requires adjusting at least two voltage levels, then the command to adjust one level at a time is executed sequentially until the target voltage level is reached. This sequential execution of the above steps avoids jumps in voltage levels and resolves the issues of abruptness and discontinuity in multi-level voltage adjustments. For example, if the jump command requires adjusting three voltage levels (e.g., adjusting to 7.5%), then three 2.5% voltage adjustment operations will be executed sequentially.
[0041] Meanwhile, if an abnormality is detected in the electronic voltage regulator module 2 during system operation, it will be short-circuited. The electronic voltage regulator module 2 mainly consists of a main thyristor and electronic control components. Due to its extremely high threshold value and heat generation during current flow, in outdoor operating scenarios, coupled with solar radiation energy of 1130W / m², the overall operating temperature will far exceed 60℃. Even with the addition of cooling devices such as air conditioning, uneven heat dissipation and ventilation convection in high-humidity environments still make the electronic components highly susceptible to failure. If any component in the main circuit thyristor or control circuit malfunctions, the entire system must be shut down, resulting in a very high overall failure or malfunction rate. Upon malfunction, the thyristor is directly set to turn-off. Therefore, reducing the number of components can lower the overall failure or malfunction rate of the electronic voltage regulator module 2; simultaneously, reducing the voltage difference reduces insulation requirements, and reducing the current reduces the tube diameter, further reducing the malfunction rate.
[0042] In summary, the long-line mechanical-electronic combined voltage regulation system and method provided by this invention combines mechanical and electronic voltage regulation to solve the problems of jumps and discontinuities in voltage adjustment during multi-level tapping. By resampling the required adjustment capacity range at the adjustment points in the middle and later sections of the line, it achieves coarse and fine selective voltage regulation by using winding tap adjustment control based on mechanical voltage regulation over a large range and electronic voltage regulation control over a small range, thus precisely controlling the tap or voltage difference of the series reactor in the line. Furthermore, the combined voltage regulation method avoids the problems of electronic secondary control failure requiring the voltage regulation device to be shut down, inability to regulate voltage, inability to simultaneously operate the series reactor bypass and voltage regulation circuit, and the need for circuit power outage switching. At the same time, since the electronic voltage regulation module is only used to compensate for the voltage difference within the tap, it does not need to consider the compensation capacity and insulation strength of the entire voltage range compared to existing all-electronic voltage regulation schemes, greatly reducing equipment costs and solving the problems of high cost, high defect rate, and forced shutdown of the entire voltage regulation device due to secondary control defects in existing electronic voltage regulation.
[0043] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.
Claims
1. A long-line electromechanical combined voltage regulating system, characterized in that, Includes mechanical voltage regulating modules and electronic voltage regulating modules; The first end of the mechanical voltage regulating module is used to connect to the high-voltage line of the power grid. The second end of the mechanical voltage regulating module is connected to the first end of the electronic voltage regulating module; The second end of the electronic voltage regulating module is used to connect to the transformer; The electronic voltage regulating module is used to compensate for the jump voltage difference caused by the mechanical voltage regulating module after the mechanical voltage regulating module adjusts the voltage level.
2. The long-line electromechanical combined voltage regulating system according to claim 1, characterized in that, It also includes a fine-tuning voltage injection transformer; The fine-tuning voltage injection transformer is connected in series between the mechanical voltage regulating module and the electronic voltage regulating module; Alternatively, the fine-tuning voltage injection transformer may be connected in series between the mechanical voltage regulating module and the high-voltage line of the power grid.
3. The long-line electromechanical combined voltage regulating system according to claim 1, characterized in that, The mechanical voltage regulating module includes at least two different voltage levels, with a level difference between adjacent voltage levels. The number of electronic components in the electronic voltage regulation module corresponds to the first-level gear difference.
4. The long-line electromechanical combined voltage regulating system according to claim 1, characterized in that, The electronic voltage regulation module includes a main thyristor and electronic control components.
5. The long-line electromechanical combined voltage regulating system according to claim 1, characterized in that, The electronic voltage regulation module includes an electronic three-level voltage regulator.
6. The long-line electromechanical combined voltage regulating system according to claim 1, characterized in that, The mechanical voltage regulating module includes a mechanical autotransformer.
7. A long-line electromechanical combined voltage regulation method, characterized in that, The method, applied to a long-line electromechanical combined voltage regulating system as described in any one of claims 1-6, comprises: The system receives voltage adjustment instructions, controls the mechanical voltage adjustment module to perform coarse voltage adjustment, and controls the electronic voltage adjustment module to compensate for the jump voltage difference caused by the mechanical voltage adjustment module.
8. The long-line electromechanical combined voltage regulation method according to claim 7, characterized in that, Also includes: If the adjustment command is to adjust the voltage difference by one level, then after the mechanical voltage adjustment module adjusts the voltage by a preset ratio, the electronic voltage adjustment module is controlled to make up the remaining voltage difference.
9. The long-line electromechanical combined voltage regulation method according to claim 8, characterized in that, Also includes: If the adjustment command is to adjust at least two voltage levels, then the command to adjust the voltage level by one level will be executed sequentially until the target voltage level is reached.
10. The long-line electromechanical combined voltage regulation method according to claim 8, characterized in that, Also includes: If an abnormality is detected in the electronic voltage regulator module, the electronic voltage regulator module will be short-circuited.