A device for improving the power supply capacity of a power distribution system and its control method

Abstract

The present invention discloses a device and method for improving the power supply capacity of a power distribution system, which relates to the field of energy storage technology, and can not only improve the power supply capacity of the power distribution system, but also enable the power distribution system to perform power-off-free operations. The device includes an energy storage power supply, an inverter, an STS static transfer module, a first power acquisition module, a first switch, a second switch, an EMS energy management module, a sampling interface, a mains interface, and a load interface; in the dynamic capacity increase mode, the first switch and the STS static transfer module are disconnected, the second switch is turned on, and the energy storage power supply is controlled to work through the EMS energy management module to dynamically increase the capacity of the power distribution subsystem; in the power-off-free mode, first control the first switch, the STS static transfer module, and the second switch to be all turned on to form a bypass to supply power to the power distribution subsystem; then control the first switch to be disconnected, and the STS static transfer module and the second switch to be all turned on to supply power to the power distribution subsystem through the energy storage power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage, and particularly relates to a device for improving the power supply capacity of a distribution system and a control method therefor. Background Art

[0002] The distribution system is a section of the system from the outlet of the step-down distribution substation to the user end. The distribution system is a power network device composed of various distribution equipment and distribution facilities for transforming voltage and directly distributing electric energy to end users.

[0003] With the economic development and the improvement of people's living standards, users' requirements for the power supply capacity and power supply reliability of the distribution system are also getting higher and higher. To improve the power supply capacity of the distribution system, it is necessary to increase the capacity of the distribution system. To improve the power supply reliability of the distribution system, it is necessary to reduce power outages. Therefore, live working is the most direct and effective measure to improve power supply reliability. The distribution operation mode has changed from outage operation to an operation mode mainly based on outage operation and supplemented by live operation, and is further changing to an operation mode of live working. Usually, the power supply capacity of the distribution system is improved by increasing the capacity of the transformer, and the live working of the distribution system is realized through an energy storage power supply.

[0004] At present, there is no device that can both improve the power supply capacity of the distribution system and enable the distribution system to achieve live working. Summary of the Invention

[0005] The present invention provides a device for improving the power supply capacity of a distribution system and a control method therefor, which solves the problem that the prior art cannot both improve the power supply capacity of the distribution system and enable the distribution system to achieve live working.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a device for improving the power supply capacity of a distribution system, including an energy storage power supply, an inverter, an STS static transfer module, a first power acquisition module, a first switch, a second switch, an EMS energy management module, a sampling interface, a mains interface, and a load interface;

[0008] The energy storage power supply is electrically connected to the inverter, the energy storage power supply is electrically connected to the first power acquisition module, and the load interface is electrically connected to the first power acquisition module through the second switch;

[0009] One end of the STS static transfer module is electrically connected to the mains interface through the first switch, and the other end of the STS static transfer module is connected to the line between the inverter and the first power acquisition module;

[0010] The EMS energy management module is used to control the sampling interface, the STS static transfer module, the converter, the energy storage power supply, the first switch, and the second switch to be electrically connected and operate;

[0011] The sampling interface, the mains interface, and the load interface are also used to connect to the sub-power distribution system;

[0012] The power supply capacity improvement device for the power distribution system further includes a dynamic capacity increase mode and an uninterruptible power supply mode;

[0013] In the dynamic capacity increase mode, the first switch and the STS static transfer module are disconnected, and the second switch is turned on. The energy storage power supply is controlled to operate by the EMS energy management module to dynamically increase the capacity of the sub-power distribution system; in the uninterruptible power supply mode, first control the first switch, the STS static transfer module, and the second switch to be all turned on to form a bypass to supply power to the sub-power distribution system; after the load of the sub-power distribution system is seamlessly transferred to the bypass power supply, control the first switch to be disconnected, and the STS static transfer module and the second switch to be all turned on to supply power to the sub-power distribution system through the energy storage power supply.

[0014] In a possible implementation manner, the EMS energy management module is further used to receive a wake-up instruction sent by an external terminal and enter the standby state according to the wake-up instruction;

[0015] In the standby state, the EMS energy management module is further used to receive a control instruction and control the conduction or disconnection of the first switch, the STS static transfer module, and the second switch according to the control instruction to enter the dynamic capacity increase mode or the uninterruptible power supply mode for operation.

[0016] In a second aspect, the present invention provides a power distribution system, including the sub-power distribution system and the power supply capacity improvement device for the power distribution system according to any one of the above;

[0017] The sub-power distribution system includes a transformer module, a second power acquisition module, a main switch, and a power distribution network module connected in series in sequence;

[0018] The sampling interface of the power supply capacity improvement device for the power distribution system is connected to the second power acquisition module, the mains interface of the power supply capacity improvement device for the power distribution system is connected to the input end of the main switch, and the load interface of the power supply capacity improvement device for the power distribution system is connected to the input end of the power distribution network module.

[0019] In a third aspect, the present invention provides a control method for a power supply capacity improvement device for a power distribution system, which is applied to the power supply capacity improvement device for the power distribution system as described above. When the power supply capacity improvement device for the power distribution system is in the dynamic capacity increase mode, the method includes:

[0020] Obtain the capacities of the sub - distribution system of the distribution system and the capacity of the power supply capacity improvement device of the distribution system, and denote them as S1 and S2 respectively;

[0021] Obtain the active power and reactive power at the output end of the transformer module of the distribution system, and denote them as P1 and Q1 respectively; Obtain the active power at the output end of the power supply capacity improvement device of the distribution system, and denote it

[0022] as Pd;

[0023] Determine the load rate, power difference and maximum power of the sub - distribution system according to the S1, the S2, the P1, and the Pd, and denote them as η, ΔP and Qmax respectively; The value range of η is between 0 and 1;

[0024] According to the magnitudes of η, the first preset value and the second preset value, switch the energy storage power supply in the power supply capacity improvement device of the distribution system to work in the charging state or the discharging state, set the ΔP as the charge adjustment value and the discharge adjustment value of the state, and correct the charge adjustment value; The value ranges of the first preset value and the second preset value are between 0 and 1;

[0025] According to the magnitudes of Q1 and Qmax, control the reactive power at the output end of the power supply capacity improvement device of the distribution system, and denote it as Qd.

[0026] In a possible implementation manner, determining the load rate, power difference and maximum power of the sub - distribution system according to the S1, the S2, the P1, the Q1, and the Pd, and denoting them as η, ΔP and Qmax respectively, specifically:

[0027] Determine η according to P1 and S1; Obtain a first preset coefficient, and determine ΔP according to P1, the first preset coefficient and S1; Determine Qmax according to Pd and S2;

[0028] η is the ratio of P1 and S1; ΔP is the difference between P1 and the product of S1 and the first preset coefficient; Qmax is the square root of the difference between the square of S2 and the square of Pd.

[0029] In a possible implementation manner, the second preset value is greater than the first preset value;

[0030] According to the magnitude relationship between η, the first preset value, and the second preset value, switch the energy storage power supply in the power distribution system power supply capacity improvement device to work in the charging state or the discharging state, set ΔP as the power adjustment value for the charging state and the discharging state, and correct the power adjustment value. Specifically, it includes:

[0031] When η is less than the first preset value, switch the energy storage power supply to work in the charging state, and set the power adjustment value as ΔP;

[0032] When η is greater than or equal to the first preset value and less than the second preset value, switch the energy storage power supply to work in the discharging state, and set the power adjustment value as ΔP;

[0033] When η is greater than or equal to the second preset value, the EMS energy management module of the power distribution system power supply capacity improvement device corrects ΔP; let ΔP be the difference between P1 and the product of the adjustment coefficient and S1;

[0034] The adjustment coefficient is the sum of the difference between η and 1 and the second preset value.

[0035] In a possible implementation manner, according to the magnitude relationship between Q1 and Qmax, control the reactive power at the output end of the power distribution system power supply capacity improvement device, and denote it as Qd. Specifically:

[0036] When Q1 is less than Qmax, take Q1 as Qd;

[0037] When Q1 is greater than or equal to Qmax, take Qmax as Qd.

[0038] In a possible implementation manner, when the power distribution system power supply capacity improvement device is in the non-power-off mode, the method includes:

[0039] The EMS energy management module of the power distribution system power supply capacity improvement device controls the STS static transfer switch to close; at the same time, controls the first switch and the second switch of the power distribution system power supply capacity improvement device to close;

[0040] Control the EMS energy management module to obtain P1 and Q1 at the output end of the transformer module through the sampling interface;

[0041] Through the EMS energy management module, take P1 as Pd and Q1 as Qd to reduce the current flowing through the main switch of the power distribution subsystem until the current flowing through the main switch is zero, and then disconnect the main switch to transfer the load of the power distribution subsystem to the bypass power supply through the first switch, the second switch, and the STS static transfer switch.

[0042] Disconnect the first switch to supply power from the energy storage power supply in a single-ended manner;

[0043] Disconnect the main switch to repair the circuit above the main switch.

[0044] In a fourth aspect, the present invention provides an electronic device, which includes a processor and a memory. At least one instruction, at least one program, a code set or an instruction set is stored in the memory, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the control method of the power supply capacity improvement device of the power distribution system described in any one of the above.

[0045] In a fifth aspect, a computer-readable storage medium is characterized in that at least one instruction, at least one program, a code set or an instruction set is stored in the storage medium, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by a processor to implement the control method of the power supply capacity improvement device of the power distribution system described in any one of the above.

[0046] The power supply capacity improvement device of the power distribution system provided by the embodiments of the present invention, when the device operates in the dynamic capacity increase mode, controls the first switch and the STS static switching module to disconnect and the second switch to conduct, and controls the energy storage module to charge or discharge through the EMS energy management module to dynamically increase the capacity of the power distribution subsystem; when the device operates in the non-stop power supply mode, first controls the first switch, the STS static switching module and the second switch to conduct to form a bypass to supply power to the power distribution subsystem, and secondly controls the first switch to disconnect, and the STS static switching module and the second switch to conduct. When a part of the circuit above the power distribution subsystem is under repair, the power storage power supply is used to supply power to the lower-level circuit of the power distribution subsystem to ensure the normal power supply of the lower-level load of the power distribution subsystem; in summary, this device can not only improve the power supply capacity of the power distribution system, that is, dynamically increase the capacity of the power distribution subsystem, but also enable the power distribution subsystem to perform non-stop power operation to ensure the power consumption stability of the user side.

[0047] The power supply capacity improvement device of the power distribution system of the present invention is applicable to low-voltage substations, especially substations with seasonal loads and weak power distribution subsystems at the end. When performing maintenance such as gear shifting of the transformer module and daily defect elimination of the substation, there is no need to cut off the power. Just control the power supply capacity improvement device of the power distribution system to operate in the non-stop power supply mode, and stable power can be continuously provided for the loads at the lower level of the power distribution subsystem during the repair or maintenance of the circuit above the power distribution subsystem.

[0048] The device for improving the power supply capacity of the distribution system provided by the present invention is connected to the substation area through a combination of series and parallel connections, which can not only realize the dynamic capacity increase of the sponge substation area and delay the investment in power grid construction, but also provide an uninterruptible power supply for daily maintenance, improve the power supply capacity of the sponge substation area, and enhance user satisfaction.

[0049] For the control method of the device for improving the power supply capacity of the distribution system provided by the present invention, when the device for improving the power supply capacity of the distribution system is in the dynamic capacity increase mode, the capacity S1 of the power distribution subsystem, the capacity S2 of the device for improving the power supply capacity of the distribution system, the active power P1, the reactive power Q1 at the output end of the transformer module, and the active power Pd at the output end of the device for improving the power supply capacity of the distribution system are obtained through the EMS energy management module. According to S1, S2, P1, Q1 and Pd, the load rate η, power difference ΔP and power maximum value Qmax of the power distribution subsystem are determined, and according to the magnitudes of η, the first preset value and the second preset value, the charging state or discharging state of the energy storage power supply is switched. ΔP is used as the power adjustment value, and the value of ΔP is automatically corrected. The device for improving the power supply capacity of the system of the present invention can realize the directional control of the power of the substation area by adjusting the output of its own active power and reactive power, and is applicable to the substation areas with heavy overload phenomena and large photovoltaic installation capacities.

[0050] The device for improving the power supply capacity of the distribution system of the present invention can adjust the topological structure of the distribution system according to the control instruction sent by the external terminal, so as to realize the seamless transfer of the load during the operation, and can realize the dynamic governance of the load curve of the substation area during the heavy overload period, and improve the comprehensive power supply capacity of the substation area. Description of the Drawings

[0051] Figure 1 It is a schematic structural diagram of a device for improving the power supply capacity of a distribution system provided by an embodiment of the present invention;

[0052] Figure 2 It is a schematic structural diagram of a distribution system provided by an embodiment of the present invention;

[0053] Figure 3 It is a method step diagram of the control method of a device for improving the power supply capacity of a distribution system provided by an embodiment of the present invention in the dynamic capacity increase mode;

[0054] Figure 4 It is a method step diagram of the control method of a device for improving the power supply capacity of a distribution system provided by an embodiment of the present invention in the non-power-off mode.

[0055] Reference numerals: 1, device for improving power supply capacity of power distribution system; 101, energy storage power supply; 102, inverter; 103, STS static transfer module; 104, first power acquisition module; 105, first switch; 106, second switch; 107, EMS energy management module; 108, sampling interface; 109, mains interface; 110, load interface; 2, power distribution subsystem; 201, transformer module; 202, second power acquisition module; 203, main switch; 204, power distribution network module. Detailed implementation manners

[0056] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0057] Hereinafter, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present disclosure, unless otherwise specified, the meaning of "a plurality" is two or more. In addition, the use of "based on" or "according to" means open and inclusive, because a process, step, calculation, or other action "based on" or "according to" one or more of the stated conditions or values may in practice be based on additional conditions or values beyond the stated ones.

[0058] In order to solve the problem that the prior art cannot both improve the power supply capacity of the power distribution system and enable the power distribution system to perform power-off-free operations, the embodiments of the present invention provide a device for improving the power supply capacity of the power distribution system and its control method.

[0059] In a first aspect, the present invention provides a device for improving the power supply capacity of a power distribution system, including an energy storage power supply 101, an inverter 102, an STS static transfer module 103, a first power acquisition module 104, a first switch 105, a second switch 106, an EMS energy management module 107, a sampling interface 108, a mains interface 109, and a load interface 110.

[0060] As Figure 1 shown, the energy storage power supply 101 is electrically connected to the inverter 102, the energy storage power supply 101 is electrically connected to the first power acquisition module 104, and the load interface 110 is electrically connected to the first power acquisition module 104 through the second switch 106.

[0061] In this embodiment, the energy storage power supply 101 may be a battery or a battery pack.

[0062] One end of the STS static transfer module 103 is electrically connected to the mains interface 109 through the first switch 105, and the other end of the STS static transfer module 103 is connected to the wire between the inverter 102 and the first power acquisition module 104.

[0063] In this embodiment, the STS static transfer module 103 is an STS static transfer system, which is a system that provides power supply for the load by switching between a preferred source and an alternative source through a static transfer method. The first power acquisition module 104 is a power meter.

[0064] The EMS energy management module 107 is used to control the sampling interface 108, the STS static transfer module 103, the inverter 102, the energy storage power supply 101, the first switch 105, and the second switch 106 to be electrically connected and work.

[0065] In this embodiment, the EMS energy management module 107 is an EMS energy management system, which can realize automatic monitoring, control, and scheduling of power equipment and systems.

[0066] The sampling interface 108, the mains interface 109, and the load interface 110 are also used to connect to the sub-power distribution system 2;

[0067] The power supply capacity improvement device 1 of the power distribution system further includes a dynamic capacity increase mode and a non-stop power supply mode;

[0068] In the dynamic capacity increase mode, the first switch 105 and the STS static transfer module 103 are disconnected, the second switch 106 is turned on, and the energy storage power supply 101 is controlled to work by the EMS energy management module 107 to dynamically increase the capacity of the sub-power distribution system 2; in the non-stop power supply mode, first control the first switch 105, the STS static transfer module 103, and the second switch 106 to be all turned on to form a bypass to supply power to the sub-power distribution system 2; after the load of the sub-power distribution system 2 is seamlessly transferred to the bypass power supply, control the first switch 105 to be disconnected, and the STS static transfer module 103 and the second switch 106 to be all turned on to supply power to the sub-power distribution system 2 through the energy storage power supply 101.

[0069] Furthermore, the EMS energy management module 107 is also used to receive a wake-up instruction sent by an external terminal and enter the standby state according to the wake-up instruction.

[0070] Among them, the wake-up instruction can be an electrical signal, and in this embodiment, the wake-up instruction is a voltage signal of 24V.

[0071] When in the standby state, the EMS energy management module 107 is further configured to receive control instructions and control the conduction or disconnection of the first switch 105, the STS static transfer module 103, and the second switch 106 according to the control instructions, so as to enter the dynamic capacity increase mode or the non-stop power supply mode for operation.

[0072] In this embodiment, after the EMS energy management module 107 is awakened by receiving a wake-up instruction sent by an external terminal, it can also enter the external input setting mode, including Mode 1 and Mode 2. The user can set Mode 1 as the dynamic capacity increase mode and Mode 2 as the non-stop power supply operation mode in this setting mode. The EMS energy management module 107 is also configured to identify the received control instructions and control the power supply capacity improvement device of the power distribution system to enter the dynamic capacity increase mode or the non-stop power supply mode for operation according to the identified control instructions. Specifically, when the received control instruction is Mode 1, the power supply capacity improvement device 1 of the power distribution system jumps to enter the dynamic capacity increase mode for operation. When the received control instruction is Mode 2, the power supply capacity improvement device 1 of the power distribution system jumps to enter the non-stop power supply mode for operation. After the operation is completed, the EMS energy management module 107 issues a sleep instruction and enters the sleep state, waiting for the next wake-up instruction.

[0073] The embodiment of the present invention provides a power supply capacity improvement device for a power distribution system. When the device operates in the dynamic capacity increase mode, it controls the first switch 105 and the STS static transfer module 103 to be disconnected and the second switch 106 to be conducted, and controls the energy storage power supply 101 to charge or discharge through the EMS energy management module 107 to dynamically increase the capacity of the power distribution subsystem 2. When the device operates in the non-stop power supply mode, first, it controls the first switch 105, the STS static transfer module 103, and the second switch 106 to be all conducted to form a bypass to supply power to the power distribution subsystem 2. Second, it controls the first switch 105 to be disconnected and the STS static transfer module 103 and the second switch 106 to be all conducted. When the upper part of the circuit of the power distribution subsystem 2 is under maintenance, the energy storage power supply 101 is used to supply power to the lower circuit of the power distribution subsystem 2 to ensure the normal power supply of the lower load of the power distribution subsystem 2. In summary, this device can not only improve the power supply capacity of the power distribution system, that is, dynamically increase the capacity of the power distribution subsystem 2, but also enable the power distribution subsystem 2 to perform non-stop operation, ensuring the power supply stability of the user side.

[0074] The power supply capacity improvement device of the present invention is applicable to low-voltage power supply areas, especially power supply areas with seasonal loads and weak ends of the power distribution subsystem 2. When performing maintenance such as gear shifting of the transformer module 201 and daily defect elimination of the power supply area, there is no need to cut off the power. Only by controlling the power supply capacity improvement device 1 of the power distribution system to operate in the non-stop power supply mode, it is possible to continuously provide a stable power supply for the lower load of the power distribution subsystem 2 during the maintenance of the upper circuit of the power distribution subsystem 2.

[0075] The power supply capacity improvement device for the distribution system provided by the embodiment of the present invention is connected to the substation area through a combination of series and parallel connections, which can not only realize the dynamic capacity increase of the sponge substation area and delay the investment in power grid construction, but also provide an uninterrupted power supply for daily maintenance, improve the power supply capacity of the sponge substation area, and enhance user satisfaction.

[0076] In a second aspect, an embodiment of the present invention provides a distribution system, including a distribution sub-system 2 and the power supply capacity improvement device 1 of any one of the above.

[0077] As Figure 2 shown, the distribution sub-system 2 includes a transformer module 201, a second power acquisition module 202, a main switch 203, and a distribution network module 204 connected in series in sequence;

[0078] The sampling interface 108 of the power supply capacity improvement device 1 of the distribution system is connected to the second power acquisition module 202, the mains interface 109 of the power supply capacity improvement device 1 of the distribution system is connected to the inlet end of the main switch 203, and the load interface 110 of the power supply capacity improvement device 1 of the distribution system is connected to the inlet end of the distribution network module 204.

[0079] In this embodiment, the transformer module 201 is a transformer device, the second power acquisition module 202 is a power meter, the main switch 203 and the distribution network module 204 together form a low-voltage switch cabinet. The input end of the transformer module 201 is connected to a 10KV power supply line, and the output end of the low-voltage switch cabinet is used to connect a load to supply power to the user end.

[0080] In a third aspect, an embodiment of the present invention provides a control method for a power supply capacity improvement device of a distribution system, which is applied to the power supply capacity improvement device 1 of the above distribution system.

[0081] As Figure 2 and Figure 3 shown, when the power supply capacity improvement device 1 of the distribution system is in the dynamic capacity increase mode, the method includes:

[0082] Step 301, obtain the capacity of the distribution sub-system 2 of the distribution system and the capacity of the power supply capacity improvement device 1 of the distribution system, and denote them as S1 and S2 respectively.

[0083] Step 302, obtain the active power and reactive power at the output end of the transformer module 201 of the distribution system, and denote them as P1 and Q1 respectively.

[0084] Step 303, obtain the active power at the output end of the power supply capacity improvement device 1 of the distribution system, and denote it as Pd.

[0085] Step 304, determine the load factor, power difference, and power maximum value of the distribution sub-system 2 according to S1, S2, P1, and Pd, and denote them as η, ΔP, and Qmax respectively.

[0086] Among them, the value range of η is between 0 and 1.

[0087] In this embodiment, step 304 is specifically: determine η according to P1 and S1; obtain a first preset coefficient, and determine ΔP according to P1, the first preset coefficient, and S1; determine Qmax according to Pd and S2.

[0088] Among them, η is the ratio of P1 to S1; ΔP is the difference between P1 and the product of S1 and the first preset coefficient; Qmax is the square root of the difference between the square of S2 and the square of Pd.

[0089] For example, the first preset coefficient takes a fixed value of 0.7.

[0090] Specifically, in this embodiment, the calculation formulas of η, ΔP, and Qmax are:

[0091] η = P1 / S1 (1)

[0092] ΔP = P1 - S1 * 0.7 (2)

[0093] Q max = √S2 2 - P d2 (3)

[0094] Step 305: According to the magnitudes of η, the first preset value, and the second preset value, switch the energy storage power supply 101 in the power distribution system power supply capacity improvement device 1 to work in the charging state or the discharging state, set ΔP as the power adjustment value for the charging state and the discharging state, and correct the power adjustment value.

[0095] Among them, the value ranges of the first preset value and the second preset value are between 0 and 1.

[0096] In this embodiment, the second preset value is greater than the first preset value, and step 305 is specifically:

[0097] When η is less than the first preset value, switch the energy storage power supply 101 to work in the charging state, and set the power adjustment value as ΔP;

[0098] When η is greater than or equal to the first preset value and at the same time less than the second preset value, switch the energy storage power supply 101 to work in the discharging state, and set the power adjustment value as ΔP;

[0099] When η is greater than or equal to the second preset value, the EMS energy management module 107 of the power distribution system power supply capacity improvement device 1 corrects ΔP; make ΔP the difference between P1 and the product of the adjustment coefficient and S1; among them, the adjustment coefficient is the sum of the difference between η and 1 and the second preset value.

[0100] For example, the first preset value is taken as 0.7, and the second preset value is taken as 0.85.

[0101] When η < 0.7, the power supply capacity improvement device 1 of the power distribution system executes the charging strategy and sets its charging value to -ΔP; when 0.7 ≤ η < 0.85, the power supply capacity improvement device 1 of the power distribution system executes the discharging strategy and sets the discharging value to ΔP; when η ≥ 0.85, the EMS energy management module 107 corrects ΔP, and the specific correction formula is:

[0102] ΔP = P1 - S1 * (η - 0.15) (4)

[0103] Where 0.15 is the difference between 1 and the second preset value.

[0104] Step 306: Control the reactive power at the output end of the power supply capacity improvement device 1 of the power distribution system according to the magnitudes of Q1 and Qmax, and denote it as Qd.

[0105] In this embodiment, step 306 is specifically:

[0106] When Q1 is less than Qmax, take Q1 as Qd;

[0107] When Q1 is greater than or equal to Qmax, take Qmax as Qd.

[0108] In the embodiment of the present invention, steps 301, 302, and 303 do not have a sequential execution order, and only need to be executed before step 304.

[0109] Such as Figure 2 and Figure 4 As shown, in another embodiment of the present invention, when the power supply capacity improvement device 1 of the power distribution system is in the non-power-off mode, the method includes:

[0110] Step 401: The EMS energy management module 107 of the power supply capacity improvement device 1 of the power distribution system controls the STS static transfer switch module 103 to close, and controls the first switch 105 and the second switch 106 of the power supply capacity improvement device 1 of the power distribution system to close.

[0111] Step 402: Control the EMS energy management module 107 to obtain P1 and Q1 at the output end of the transformer module 201 through the sampling interface 108.

[0112] Step 403: Use P1 as Pd and Q1 as Qd through the EMS energy management module 107 to reduce the current flowing through the main switch 203 of the power distribution subsystem 2 until the current flowing through the main switch 203 is zero, and then disconnect the main switch 203 to transfer the load of the power distribution subsystem 2 to the bypass power supply via the first switch 105, the second switch 106, and the STS static transfer switch module 103.

[0113] Step 404: Disconnect the first switch 105 to supply power from the energy storage power supply 101 alone-endedly.

[0114] Step 405: Disconnect the main switch 203 to repair the circuit above the main switch 203.

[0115] After the staff repairs the circuit above the main switch 203, the method further includes:

[0116] Step 406: Close the first switch 105;

[0117] Step 407: Use P1 as Pd and Q1 as Qd through the EMS energy management module 107;

[0118] Step 408: Close the main switch 203 to resume power supply from the transformer module 201 to the power distribution network module 204 through the main switch 203;

[0119] Step 409: Control the first switch 105 and the STS static transfer module 103 to disconnect, and control the STS static transfer module 103 to exit the working state, so that the device works in the power distribution network capacity increase mode;

[0120] Step 410: After the device finishes working, the EMS energy management module 107 enters the sleep mode and waits to be woken up by an external wake-up instruction again.

[0121] For the control method of the power supply capacity improvement device of the distribution system provided by the embodiment of the present invention, when the power supply capacity improvement device 1 of the distribution system is in the dynamic capacity increase mode, the EMS energy management module 107 is used to obtain the capacity S1 of the power distribution subsystem 2, the capacity S2 of the power supply capacity improvement device 1 of the distribution system, the active power P1, the reactive power Q1 at the output end of the transformer module 201, and the active power Pd at the output end of the power supply capacity improvement device 1 of the distribution system. According to S1, S2, P1, Q1 and Pd, the load rate η, power difference ΔP and power maximum value Qmax of the power distribution subsystem 2 are determined, and according to the magnitudes of η, the first preset value and the second preset value, the charging state or discharging state of the energy storage power supply 101 is switched, ΔP is used as the power adjustment value, and the value of ΔP is automatically corrected. The power supply capacity improvement device of the present invention can achieve directional control of the power of the substation area by adjusting the output of its own active power and reactive power, and is applicable to the substation areas with heavy overload phenomena and large photovoltaic installation capacities.

[0122] The power supply capacity improvement device of the distribution system of the present invention can adjust the topological structure of the distribution system according to the control instruction sent by the external terminal, so as to realize seamless transfer of the load during operation, and can realize dynamic management of the load curve of the substation area during heavy overload, and improve the comprehensive power supply capacity of the substation area.

[0123] Fourthly, the present invention provides an electronic device, which includes a processor and a memory. At least one instruction, at least one program, a code set or an instruction set is stored in the memory, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the control method of the power supply capacity improvement device of the power distribution system according to any one of the above.

[0124] Fifthly, a computer-readable storage medium is characterized in that at least one instruction, at least one program, a code set or an instruction set is stored in the storage medium, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the control method of the power supply capacity improvement device of the power distribution system according to any one of the above.

[0125] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, a data center, etc. that includes one or more integrated available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

[0126] The above are only the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A control method for a device to improve the power supply capacity of a power distribution system, characterized in that The device for enhancing the power supply capacity of the distribution system includes an energy storage power supply, an inverter, an STS static transfer module, a first power acquisition module, a first switch, a second switch, an EMS energy management module, a sampling interface, a mains interface, and a load interface; The energy storage power supply is electrically connected to the inverter, the energy storage power supply is electrically connected to the first power acquisition module, and the load interface is electrically connected to the first power acquisition module through the second switch; One end of the STS static transfer module is electrically connected to the mains interface through the first switch, and the other end of the STS static transfer module is connected to the wire between the inverter and the first power acquisition module; The EMS energy management module is used to control the sampling interface, the STS static transfer module, the inverter, the energy storage power supply, the first switch, and the second switch to work in an electrically connected manner; The sampling interface, the mains interface, and the load interface are also used to connect to the sub-distribution system; The device for enhancing the power supply capacity of the distribution system further includes a dynamic capacity increase mode and an uninterrupted power supply mode; in the dynamic capacity increase mode, the first switch and the STS static transfer module are disconnected, the second switch is turned on, and the energy storage power supply is controlled to work through the EMS energy management module to dynamically increase the capacity of the sub-distribution system; in the uninterrupted power supply mode, first control the first switch, the STS static transfer module, and the second switch to be all turned on to form a bypass to supply power to the sub-distribution system; after the load of the sub-distribution system is seamlessly transferred to the bypass power supply, control the first switch to be disconnected, and the STS static transfer module and the second switch to be all turned on to supply power to the sub-distribution system through the energy storage power supply; The EMS energy management module is further used to receive a wake-up instruction sent by an external terminal and enter the standby state according to the wake-up instruction; In the standby state, the EMS energy management module is further used to receive a control instruction and control the conduction or disconnection of the first switch, the STS static transfer module, and the second switch according to the control instruction to enter the dynamic capacity increase mode or the uninterrupted power supply mode to work; When the device for enhancing the power supply capacity of the distribution system is in the dynamic capacity increase mode, the method includes: Obtain the capacity of the sub-distribution system of the distribution system and the capacity of the device for enhancing the power supply capacity of the distribution system, and record them as S1 and S2 respectively; Obtain the active power and reactive power at the output end of the transformer module of the distribution system, and record them as P1 and Q1 respectively; obtain the active power at the output end of the device for enhancing the power supply capacity of the distribution system, and record it as Pd; Determine the load rate, power difference, and power maximum value of the sub-distribution system according to S1, S2, P1, and Pd, and record them as η, ΔP, and Qmax respectively; the value range of η is between 0 and 1; According to the magnitudes of η, the first preset value, and the second preset value, switch the energy storage power supply in the power distribution system power supply capacity improvement device to work in the charging state or the discharging state, set ΔP as the charge adjustment value and the discharge adjustment value of the state, and correct the adjustment value of the charge amount; the value ranges of the first preset value and the second preset value are between 0 and 1; According to the magnitudes of Q1 and Qmax, control the reactive power at the output end of the power distribution system power supply capacity improvement device, and denote it as Qd.

2. The method according to claim 1, characterized in that, Determine the load rate, power difference, and power maximum value of the power distribution subsystem according to S1, S2, P1, Q1, and Pd, and denote them as η, ΔP, and Qmax respectively, specifically: Determine η according to P1 and S1; obtain a first preset coefficient, and determine ΔP according to P1, the first preset coefficient, and S1; determine Qmax according to Pd and S2; η is the ratio of P1 and S1; ΔP is the difference between P1 and the product of S1 and the first preset coefficient; Qmax is the square root of the difference between the square of S2 and the square of Pd.

3. The method according to claim 2, wherein The second preset value is greater than the first preset value; The step of switching the energy storage power supply in the power distribution system power supply capacity improvement device to work in the charging state or the discharging state according to the magnitudes of η, the first preset value, and the second preset value, setting ΔP as the charge adjustment value and the discharge adjustment value of the state, and correcting the adjustment value of the charge amount specifically includes: When η is less than the first preset value, switch the energy storage power supply to work in the charging state, and set the charge adjustment value as ΔP; When η is greater than or equal to the first preset value and less than the second preset value, switch the energy storage power supply to work in the discharging state, and set the charge adjustment value as ΔP; When η is greater than or equal to the second preset value, the EMS energy management module of the power distribution system power supply capacity improvement device corrects ΔP; let ΔP be the difference between P1 and the product of the adjustment coefficient and S1; The adjustment coefficient is the sum of the difference between η and 1 and the second preset value.

4. The method according to claim 3, wherein The step of controlling the reactive power at the output end of the power distribution system power supply capacity improvement device according to the magnitudes of Q1 and Qmax, and denoting it as Qd specifically includes: When Q1 is less than Qmax, use Q1 as Qd; When Q1 is greater than or equal to Qmax, use Qmax as Qd.

5. The method according to any one of claims 2-4, characterized in that, When the power distribution system power supply capacity improvement device is in the non-power-off mode, the method includes: The EMS energy management module of the power distribution system power supply capacity improvement device controls the STS static switch module to close; at the same time, controls the first switch and the second switch of the power distribution system power supply capacity improvement device to close; Control the EMS energy management module to obtain P1 and Q1 at the output end of the transformer module through the sampling interface; Through the EMS energy management module, take P1 as Pd and Q1 as Qd to reduce the current flowing through the main switch of the distribution sub-system until the current flowing through the main switch is zero, then disconnect the main switch to transfer the load of the distribution sub-system to the bypass power supply via the first switch, the second switch and the STS static transfer module; Disconnect the first switch to supply power from the energy storage power supply alone; Disconnect the main switch to repair the circuit above the main switch.

6. A power distribution system, characterized in that, It includes the distribution sub-system and the device for enhancing the power supply capacity of the distribution system described in claim 1; The distribution sub-system includes a transformer module, a second power acquisition module, a main switch, and a power distribution network module connected in series in sequence; The sampling interface of the device for enhancing the power supply capacity of the distribution system is connected to the second power acquisition module, the mains interface of the device for enhancing the power supply capacity of the distribution system is connected to the input end of the main switch, and the load interface of the device for enhancing the power supply capacity of the distribution system is connected to the input end of the power distribution network module.

7. An electronic device, characterized in that, The electronic device includes a processor and a memory. At least one instruction, at least one program, a code set or an instruction set is stored in the memory. The at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the control method for the device for enhancing the power supply capacity of the distribution system according to any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, At least one instruction, at least one program, a code set or an instruction set is stored in the storage medium. The at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the control method for the device for enhancing the power supply capacity of the distribution system according to any one of claims 1-5.

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