Method and system for setting loss-of-voltage criterion of voltage time type feeder automation of power distribution network

Abstract

The application discloses a power distribution network voltage time type feeder automation loss of voltage criterion setting method and system. The power distribution network voltage time type feeder automation loss of voltage criterion setting method comprises the following steps: step A: calculating the equivalent impedance amplitude of the negative sequence network equivalent circuit when two-phase short circuit occurs in the power distribution network; step B: judging whether the distributed energy access capacity and the voltage setting value in the loss of voltage criterion meet the loss of voltage tripping requirement; if yes, it indicates that when the power distribution area fails and the outgoing circuit breaker trips, the voltage on both sides of each sectionalizing switch meets the loss of voltage criterion, and the loss of voltage tripping can be realized on both sides; if not, the voltage setting value of the loss of voltage criterion is adjusted. The application can judge whether the voltage setting value in the voltage time type feeder automation loss of voltage criterion meets the loss of voltage tripping requirement, and ensures the reliability of the sectionalizing switch loss of voltage criterion in the voltage time type feeder automation judgment process.

Description

Technical Field

[0001] This invention relates to the field of distribution network feeder automation, and particularly to voltage-time type feeder automation for distribution networks with a high proportion of distributed energy access, specifically a method and system for setting undervoltage criteria in voltage-time type feeder automation for distribution networks. Background Technology

[0002] When a fault occurs in a distribution network, a rapid and accurate local feeder automation fault diagnosis method can effectively shorten the power outage time, accelerate power restoration, achieve automatic fault diagnosis and rapid and accurate fault location, and quickly isolate the faulty section through feeder switches, restoring power to non-faulty areas, effectively reducing user power outage time and narrowing the scope of user power outages. Currently, traditional distribution network feeder automation generally adopts voltage-time type feeder automation, which does not require communication and only needs to collect electrical quantities locally for fault diagnosis. Furthermore, voltage-time type feeder automation requires fewer reclosing operations, needing only two reclosings to isolate the fault, making it the common fault diagnosis method for overhead distribution networks in China.

[0003] Under the "dual carbon" context, the decentralized integration of distributed energy resources into the distribution network can effectively solve problems such as the local consumption of new energy power generation. Large-scale integration of distributed energy resources into the distribution network has become an inevitable development trend for the future power grid. After large-scale integration of distributed energy resources into the distribution network, the distribution network exhibits a new power supply mode of "multi-point and multi-source" and fault current characteristics of "multi-point restricted feedin". Traditional voltage-time type feeder automation fault judgment methods for distribution networks will encounter a series of problems such as switch tripping failures, and cannot meet the development needs of future new smart distribution networks.

[0004] Therefore, considering the impact of distributed energy access, ensuring smooth double-sided undervoltage tripping of sectionalizing switches is a fundamental prerequisite for the successful application of voltage-time type feeder automation in large-scale distributed energy distribution networks and for leveraging its inherent advantages. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, and address the problem of voltage-time type feeder automatic undervoltage tripping in distribution networks caused by distributed energy access, this invention aims to provide a method and system for setting the voltage-time type feeder automatic undervoltage criterion in distribution networks with a high proportion of distributed energy. Based on the equivalent impedance of the distribution network transformer, the equivalent impedance of the load, and the installed capacity of the distributed energy, it determines whether the voltage setting value in the voltage-time type feeder automatic undervoltage criterion meets the undervoltage tripping requirements, thereby ensuring the reliability of the sectionalizing switch undervoltage criterion during the voltage-time type feeder automatic assessment process.

[0006] Therefore, the present invention adopts the following technical solution: a method for setting the undervoltage criterion for automatic feeder voltage time-type distribution network, comprising:

[0007] Step A: Calculate the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 |;

[0008] Step B: Determine whether the distributed energy access capacity and voltage setting value in the undervoltage criterion in the distribution network meet the undervoltage tripping requirements;

[0009] If the condition is met, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each sectional switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0010] If the conditions are not met, adjust the voltage setting value of the undervoltage criterion.

[0011] This invention considers the current output characteristics during the fault ride-through of distributed energy resources, neglecting line impedance. It analyzes the maximum phase-to-phase voltage amplitude at each section switch after a fault occurs in the distribution network and the outgoing circuit breaker trips. This is the maximum phase-to-phase voltage amplitude at each section switch after a two-phase short-circuit fault occurs and the outgoing circuit breaker trips. The maximum phase-to-phase voltage amplitude is compared with the voltage setting value in the undervoltage criterion. After a two-phase short-circuit fault occurs in the distribution network and the outgoing circuit breaker trips, the phase-to-phase voltage at each section switch of the distribution network is affected by the fault current of the distributed energy resources and the circuit impedance. Considering that the maximum fault current amplitude of the distributed energy resources is generally 1.2 times the rated current and the relationship between the rated current and capacity of the distributed energy resources, based on the equivalent impedance amplitude of the equivalent circuit of the negative sequence network when a two-phase short circuit occurs in the distribution network and the total installed capacity of the distributed energy resources connected downstream of the main branch outgoing circuit breaker, it is determined whether the undervoltage criterion can be met after the distributed energy resources are connected. If not, the voltage setting value can be adjusted according to the analysis results.

[0012] Furthermore, step A includes the following specific steps:

[0013] Step A1: Based on the load impedance parameters of the distribution network, calculate the equivalent impedance magnitude |Z| of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 |, When line impedance is ignored, the fault location at different locations |Z feq2 Same;

[0014] Step A2: Calculate the total installed capacity of distributed energy resources connected downstream of the main branch circuit breaker. ΩDG This is a collection of distributed energy designations connected downstream of the main branch circuit breaker.

[0015] Furthermore, step A1 includes the following steps:

[0016] Step 1): Calculate the equivalent impedance of the DG dedicated transformer and the user distribution transformer in the distribution network, as well as the equivalent impedance of the connected loads;

[0017] Step 2): Ignoring line impedance, the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 |

[0018] Furthermore, step B includes the following specific steps:

[0019] Step B1: Calculate the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 | Total installed capacity of distributed energy resources connected downstream of the main and branch circuit breakers Rated line voltage amplitude U of distribution network N And the voltage setting value U for the automatic undervoltage judgment of voltage-time type feeders set Substitution formula (1):

[0020]

[0021] If equation (1) is satisfied, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each section switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0022] Step B2: If equation (1) is not satisfied, adjust the voltage setting value of the undervoltage criterion so that the voltage setting value U set Satisfying equation (2):

[0023]

[0024] In the formula, k represents the voltage setting coefficient, which is the ratio of the voltage setting value to the rated voltage of the distribution network.

[0025] Furthermore, in step B1, equation (1) is derived based on the maximum output current of the distributed energy source being 1.2 times the rated current.

[0026] Another technical solution adopted in this invention is: a distribution network voltage time-type feeder automatic undervoltage judgment setting system, which includes:

[0027] Equivalent Impedance Amplitude Calculation Unit: Calculates the equivalent impedance amplitude of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network |Z feq2 |;

[0028] Judgment Unit: Determines whether the distributed energy access capacity and voltage setting value in the undervoltage criterion in the distribution network meet the undervoltage tripping requirements;

[0029] If the condition is met, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each sectional switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0030] If the conditions are not met, adjust the voltage setting value of the undervoltage criterion.

[0031] Furthermore, the equivalent impedance magnitude calculation unit includes the following specific components:

[0032] Based on the load impedance parameters of the distribution network, the equivalent impedance magnitude |Z| of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network is calculated. feq2 |, When line impedance is ignored, the fault location at different locations |Z feq2 Same;

[0033] Calculate the total installed capacity of distributed energy resources connected downstream of the main branch circuit breaker. Ω DG This is a collection of distributed energy designations connected downstream of the main branch circuit breaker.

[0034] Furthermore, based on the load impedance parameters of the distribution network, the equivalent impedance magnitude |Z| of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network is calculated. feq2 |, When line impedance is ignored, the fault location at different locations |Z feq2 The same applies, including the following specific details:

[0035] Calculate the equivalent impedance of the DG dedicated transformer and the user distribution transformer in the distribution network, as well as the equivalent impedance of the connected loads;

[0036] Ignoring line impedance, the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 |

[0037] Furthermore, the judgment unit includes the following specific contents:

[0038] The equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 | Total installed capacity of distributed energy resources connected downstream of the main and branch circuit breakers Rated line voltage amplitude U of distribution network N And the voltage setting value U for the automatic undervoltage judgment of voltage-time type feeders set Substitution formula (1):

[0039]

[0040] If equation (1) is satisfied, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each section switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0041] If equation (1) is not satisfied, then adjust the voltage setting value of the undervoltage criterion so that the voltage setting value U set Satisfying equation (2):

[0042]

[0043] In the formula, k represents the voltage setting coefficient, which is the ratio of the voltage setting value to the rated voltage of the distribution network.

[0044] Furthermore, equation (1) is derived based on the maximum output current of distributed energy being 1.2 times the rated current.

[0045] The beneficial effects of this invention are as follows:

[0046] 1. This invention takes into account the impact of distributed energy access and is not affected by the intermittency of distributed energy.

[0047] 2. This invention addresses the problem of voltage-time type feeder automation sectionalizing switch failure due to undervoltage after a high proportion of distributed energy access. It proposes to determine whether the original undervoltage criterion is met after a fault in the distribution network containing distributed energy, based on the original undervoltage tripping function, and proposes the setting basis for the voltage setting value.

[0048] 3. The calculation principle of the switch setting value in this invention is clear and easy to implement. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of a typical high-proportion distributed energy distribution network equivalent system in a specific embodiment of the present invention. Detailed Implementation

[0050] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0051] Example 1

[0052] The undervoltage judgment criterion for voltage-time type feeder automation is generally that the effective values ​​of the phase-to-phase voltage on both the power supply side and the load side are lower than k times the rated voltage. Typically, the undervoltage judgment is made by sampling the phase-to-phase voltage amplitude of phases ab on the power supply side, and by sampling the phase-to-phase voltage amplitude of phases cb on the load side. The criteria for undervoltage tripping of sectionalizing switches are as follows:

[0053] U ab_电源侧 <U set &U cb_负荷侧 <U set (3)

[0054] U set =kU N (0 <k<1)

[0055] In equation (3), U ab_电源侧 U represents the phase-to-phase voltage amplitude of the segmented switching power supply. cb_负荷侧 U represents the phase-to-phase voltage amplitude of cb on the load side of the sectionalizing switch. set U is the voltage setting value. N This refers to the rated line voltage amplitude of the distribution network.

[0056] When a fault occurs in the distribution network and the outgoing circuit breaker trips, the sectionalizing switch near the grid connection point may fail to trip due to the supporting effect of distributed energy on the voltage of the grid connection point.

[0057] This embodiment proposes a voltage-time type feeder automation undervoltage criterion setting method for high-proportion distributed energy distribution networks. This method considers the current output characteristics during the fault ride-through of distributed energy, ignores line impedance, and analyzes the maximum phase-to-phase voltage amplitude at each section switch after a fault occurs in the distribution network and the outgoing circuit breaker trips. This is equivalent to the maximum phase-to-phase voltage amplitude at each section switch after a two-phase short-circuit fault occurs and the outgoing circuit breaker trips. The maximum phase-to-phase voltage amplitude is compared with the voltage setting value in the undervoltage criterion to determine whether the undervoltage criterion is met after the distributed energy is connected. If not, the voltage setting value can be adjusted based on the analysis results. This method can determine whether the voltage setting value in the voltage-time type feeder automation undervoltage criterion meets the undervoltage tripping requirements based on the equivalent impedance of the distribution network transformer, the equivalent impedance of the load, and the installed capacity of the distributed energy.

[0058] A method for setting the undervoltage criterion for automated feeder voltage time-based induction in a high-proportion distributed energy distribution network, comprising the following steps:

[0059] Step A: Calculate the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 The specific steps involved are as follows:

[0060] Step A1: Based on the load impedance parameters of the distribution network (including transformer equivalent impedance, load equivalent impedance, etc.), calculate the maximum equivalent impedance amplitude |Z| of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 |, When line impedance is ignored, the fault location at different locations |Z feq2 They are the same;

[0061] Step (1): Calculate the equivalent impedance of the DG dedicated transformer and the user distribution transformer in the distribution network, as well as the equivalent impedance of the connected load;

[0062] according to Figure 1 The equivalent impedance of the transformer is Z (as indicated in the diagram). T1 Z T2 Z T3 Z T4 The equivalent impedances of the loads are respectively Z LD1 Z LD2 Z LD3 Z LD4 .

[0063] Step (2): Ignoring line impedance, the equivalent impedance amplitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network.feq2 |;

[0064] according to Figure 1 According to the annotation, the equivalent impedance amplitude of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network is shown in equation (4).

[0065]

[0066] Step A2: Calculate the total installed capacity of distributed energy resources connected downstream of the main branch circuit breaker.

[0067] according to Figure 1 According to the annotation, the total installed capacity of distributed energy downstream of the distribution network outgoing circuit breaker can be obtained as shown in equation (5).

[0068]

[0069] Step B: Determine whether the distributed energy access capacity and voltage setting value in the undervoltage criterion of the distribution network meet the undervoltage tripping requirements. This includes the following steps:

[0070] Step B1: Calculate the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 | Total installed capacity of distributed energy resources connected downstream of the main and branch circuit breakers Rated line voltage U of distribution network N And the voltage setting value U for the automatic undervoltage judgment of voltage-time type feeders set Substitution formula (1).

[0071]

[0072] If equation (1) is satisfied, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each section switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0073] It should be noted that Equation (1) is derived based on the maximum output current of distributed energy being 1.2 times the rated current.

[0074] Step B2: If equation (1) is not satisfied, the voltage setting value of the undervoltage criterion can be adjusted so that the voltage setting value U set It satisfies equation (2).

[0075] U set =kU N (0 < k < 1) (2)

[0076]

[0077] In the formula, k represents the voltage setting coefficient, which is the ratio of the voltage setting value to the rated voltage of the distribution network.

[0078] Example 2

[0079] This embodiment provides a distribution network voltage time-type feeder automatic undervoltage criterion setting system, which consists of an equivalent impedance amplitude calculation unit and a judgment unit.

[0080] Equivalent Impedance Amplitude Calculation Unit: Calculates the equivalent impedance amplitude of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network |Z feq2 |; Including the following specific content:

[0081] Based on the load impedance parameters of the distribution network, the equivalent impedance magnitude |Z| of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network is calculated. feq2 |, When line impedance is ignored, the fault location at different locations |Z feq2 |Same; including the following specific contents: calculating the equivalent impedance of the DG dedicated transformer and user distribution transformer in the distribution network, as well as the equivalent impedance of the connected load; ignoring line impedance, the equivalent impedance amplitude of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network|Z feq2 |

[0082] Calculate the total installed capacity of distributed energy resources connected downstream of the main branch circuit breaker. Ω DG This is a collection of distributed energy designations connected downstream of the main branch circuit breaker.

[0083] Judgment Unit: Determines whether the distributed energy access capacity and voltage setting value in the undervoltage criterion of the distribution network meet the undervoltage tripping requirements; including the following specific contents:

[0084] The equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when a two-phase short circuit occurs in the distribution network. feq2 | Total installed capacity of distributed energy resources connected downstream of the main and branch circuit breakers Rated line voltage amplitude U of distribution network N And the voltage setting value U for the automatic undervoltage judgment of voltage-time type feeders set Substitution formula (1):

[0085]

[0086] If equation (1) is satisfied, it means that when a fault occurs in the power distribution area and the outgoing circuit breaker trips, the voltage on both sides of each section switch meets the undervoltage criterion, and the circuit breaker can be tripped on both sides due to undervoltage.

[0087] If equation (1) is not satisfied, then adjust the voltage setting value of the undervoltage criterion so that the voltage setting value U set Satisfying equation (2):

[0088]

[0089] In the formula, k represents the voltage setting coefficient, which is the ratio of the voltage setting value to the rated voltage of the distribution network.

[0090] It should be noted that Equation (1) is derived based on the maximum output current of distributed energy being 1.2 times the rated current.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any modifications or equivalent substitutions to the specific implementation of the present invention that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A method for setting a loss-of-voltage criterion for voltage time-type feeder automation in a power distribution network, characterized in that, Comprising: Step A: Calculate the equivalent impedance magnitude |Z of the negative sequence network equivalent circuit when two-phase short circuit occurs in the power distribution network feq2 |; Step B: judging whether the voltage setting value in the distributed energy access capacity and the voltage setting value in the voltage loss criterion in the power distribution network meet the voltage loss tripping requirement; If yes, it means that when the power distribution area fails and the outgoing line circuit breaker trips, the voltage on both sides of each sectionalizing switch meets the voltage loss criterion, and the voltage loss tripping can be performed on both sides; If no, adjust the voltage setting value in the voltage loss criterion; Step B includes the following specific steps: Step B1: the equivalent impedance amplitude |Z feq2 | The total installed capacity of the distributed energy accessed downstream of the main branch outgoing circuit breaker The rated line voltage amplitude U of the distribution network N The voltage setting value U of the loss-of-voltage criterion of the voltage time type feeder automation set Substitute (1) into (2): In the formula, Ω DG is a distributed energy label set accessed by the downstream circuit breaker of the main branch circuit If formula (1) is met, it means that when the power distribution area fails and the outgoing line circuit breaker trips, the voltage on both sides of each sectionalizing switch meets the voltage loss criterion, and the voltage loss tripping can be performed on both sides. Step B2: If the formula (1) is not satisfied, adjust the voltage setting value of the loss of pressure criterion, so that the voltage setting value U set satisfies the formula (2): In the formula, k represents the setting coefficient of the voltage setting value, which is the ratio of the voltage setting value to the rated voltage of the power distribution network.

2. The method of setting the loss of voltage criterion for voltage time-type feeder automation of the electrical distribution network of claim 1, characterized in that, Step A includes the following specific steps: Step A1: According to the load impedance parameters of the power distribution network, the equivalent impedance amplitude |Z feq2 | of the negative sequence network equivalent circuit when two-phase short circuit occurs in the power distribution network is calculated. feq2 | is the same when the line impedance is ignored. Step A2: Calculate the total installed capacity of the distributed energy sources accessed downstream of the main branch line outlet circuit breaker 3. The method of setting a loss of voltage criterion for a voltage time-type feeder automation of a power distribution network according to claim 2, characterized in that, Step A1 includes the following steps: Step 1): calculate the equivalent impedance of the DG dedicated transformer and the user power distribution transformer in the power distribution network, and the equivalent impedance of the connected load; Step 2): The equivalent impedance amplitude |Z of the negative sequence network equivalent circuit when two-phase short circuit occurs in the distribution network, ignoring the line impedance feq2 | 4. The method of setting a loss of voltage criterion for voltage time-type feeder automation of a power distribution network of claim 1, wherein, In step B1, formula (1) is obtained according to the maximum output current of the distributed energy being 1.2 times the rated current.

5. A power distribution network voltage time pattern feeder automation loss of voltage criterion setting system, characterized by, Comprising: The equivalent impedance amplitude calculation unit calculates the equivalent impedance amplitude |Z of the negative sequence network equivalent circuit when two-phase short circuit occurs in the power distribution network feq2 |; A judging unit: judging whether the voltage setting value in the distributed energy access capacity and the voltage setting value in the voltage loss criterion in the power distribution network meet the voltage loss tripping requirement; If yes, it means that when the power distribution area fails and the outgoing line circuit breaker trips, the voltage on both sides of each sectionalizing switch meets the voltage loss criterion, and the voltage loss tripping can be performed on both sides; If no, adjust the voltage setting value in the voltage loss criterion; The judging unit includes the following specific contents: The equivalent impedance amplitude |Z feq2 The total installed capacity of the distributed energy accessed downstream of the main branch outgoing circuit breaker The rated line voltage amplitude U of the distribution network N The voltage setting value U of the voltage time type feeder automation loss of voltage criterion set The formula (1): In the formula, Ω DG is a distributed energy label set accessed by the downstream circuit breaker of the main branch circuit If formula (1) is met, it means that when the power distribution area fails and the outgoing line circuit breaker trips, the voltage on both sides of each sectionalizing switch meets the voltage loss criterion, and the voltage loss tripping can be performed on both sides. If the formula (1) is not satisfied, the voltage setting value of the pressure loss criterion is adjusted so that the voltage setting value U set satisfies the formula (2): In the formula, k represents the setting coefficient of the voltage setting value, which is the ratio of the voltage setting value to the rated voltage of the power distribution network.

6. The distribution system voltage time-based feeder automation loss-of- voltage criterion setting system of claim 5, wherein, The equivalent impedance amplitude calculation unit includes the following specific contents: According to the load impedance parameters of the distribution network, the equivalent impedance amplitude |Z feq2 | of the negative sequence network equivalent circuit when two-phase short circuit occurs in the distribution network is calculated feq2 | is the same when the line impedance is ignored. Total installed capacity of distributed energy accessed downstream of main branch outgoing line circuit breaker Ω DG Label collection for distributed energy accessed downstream of main branch outgoing line circuit breaker 7. The distribution system voltage time-based feeder automation loss of voltage criterion setting system of claim 6, wherein, According to the load impedance parameters of the distribution network, the equivalent impedance amplitude |Z feq2 | of the negative sequence network equivalent circuit when two-phase short circuit occurs in the distribution network is calculated feq2 | is the same when the line impedance is ignored, including the following specific contents: Calculate the equivalent impedance of the DG dedicated transformer and the user power distribution transformer in the power distribution network, and the equivalent impedance of the connected load; Neglecting line impedance, the equivalent impedance amplitude |Z feq2 | of the negative sequence network equivalent circuit of distribution network with two-phase short circuit is calculated.

8. The distribution system voltage time-based feeder automation loss of voltage criterion setting system of claim 5, wherein, Formula (1) is obtained according to the maximum output current of the distributed energy being 1.2 times the rated current.

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