A method and system for line backup protection adaptive analysis

Abstract

This invention provides a method and system for adaptive analysis of line backup protection. The method includes determining the fault type based on fault recording results when a fault occurs on a power transmission line of a power system containing renewable energy sources. The fault types include symmetrical faults within a zone, phase-to-phase short-circuit faults within a zone, and single-phase ground faults. When the fault type is a symmetrical fault or a phase-to-phase short-circuit fault within a zone, the ratio of the fault phase current amplitude and the threshold value of the renewable energy side protection operation zone are calculated respectively. When the fault type is a single-phase ground fault, the current flowing through the additional impedance on the renewable energy side and the threshold value of the renewable energy side protection operation zone are calculated respectively. When the calculation results for different fault types meet the corresponding criteria, the reliable operation of the renewable energy side protection is determined. This method and system clearly define the correct operation area of ​​the relay protection on the transmission line, providing a basis for improving relay protection principles and selecting devices, and has significant engineering implications for the safe operation of the future power grid.

Description

Technical Field

[0001] This invention relates to the field of new power system protection technology, and more specifically, to a method and system for adaptive analysis of line backup protection. Background Technology

[0002] Relay protection is a crucial foundation for ensuring the safe and stable operation of the power grid. As the first line of defense for the power grid, relay protection plays a vital role in preventing large-scale power outages. Existing technologies have established a relatively complete relay protection system based on the fault characteristics of synchronous machines, ensuring that the correct operation rate of the main grid protection system remains above 99.7%, thereby guaranteeing that the power grid operates safely and stably most of the time.

[0003] However, systemic risks always exist. In particular, with the transformation of traditional power systems to new power systems, the power supply structure is shifting from traditional power sources with high inertia and strong damping to new energy sources with low inertia and weak damping; the power grid is changing from AC grids to AC / DC hybrid grids, which leads to fundamental changes in fault characteristics, posing unprecedented challenges and impacts to relay protection.

[0004] Due to the limitations of device tolerance and control strategy, power electronic equipment can no longer be equivalent to a constant electromotive force power source. Fault currents exhibit characteristics such as limited amplitude, controlled phase angle, and high harmonic content. These characteristics lead to a large phase angle difference between the currents on both sides of the line after a fault, and the backup protection operating zone shifts, resulting in situations such as failure to operate at the line outlet or false operation in the opposite direction, threatening the safe and stable operation of the system.

[0005] Therefore, in order to address the inapplicability of existing protection principles and clarify the potential for improvement in the performance of protection principles, it is urgent to propose an adaptive analysis method for line backup protection to identify the areas where line relay protection can operate correctly. Summary of the Invention

[0006] To address the technical problem that existing protection principles are inapplicable during the transition from traditional power systems to new power systems, leading to line outgoing fault failures and erroneous operation in the opposite direction, which threaten the safe and stable operation of the power system, this invention provides a line backup protection adaptability analysis method and system.

[0007] According to one aspect of the present invention, the present invention provides a method for adaptive analysis of line backup protection, comprising:

[0008] When a fault occurs on a power transmission line of a power system that includes new energy sources, the fault type is determined based on the fault recording results. The fault types include symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults.

[0009] Calculate the radius of the directional impedance circle based on the custom distance I protection setting value and the total impedance of the outgoing line;

[0010] When the fault type is a symmetrical fault within the zone, the first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the system side of the line, and the first threshold of the new energy side protection action zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the current on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle.

[0011] When the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone meet the first protection criterion, the new energy side protection is determined to be reliably activated.

[0012] When the fault type is an intra-phase short circuit fault, the second amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the system side of the line, and the second threshold of the new energy side protection action zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the phase transition resistance, and the radius of the directional impedance circle.

[0013] When the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone meet the second protection criterion, the new energy side protection is determined to be reliable.

[0014] When the fault type is a single-phase ground fault, the current flowing through the additional impedance of the new energy side is calculated based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current. The third threshold of the protection action zone on the new energy side is calculated based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle.

[0015] When the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone satisfy the third protection criterion, the new energy side protection is determined to be reliable.

[0016] According to another aspect of the present invention, the present invention provides a line backup protection adaptive analysis system, the system comprising:

[0017] The fault type module is used to determine the fault type based on the fault recording results when a fault occurs on the power transmission line of a power system containing new energy sources. The fault types include symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults.

[0018] The first calculation module is used to calculate the radius of the directional impedance circle based on the custom distance I protection setting value and the total impedance of the outgoing line.

[0019] The second calculation module is used to calculate the first amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the system side when the fault type is a symmetrical fault within the zone, and to calculate the first threshold of the new energy side protection action zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the current on both sides of the fault phase, the transition resistance and the radius of the directional impedance circle.

[0020] The first determination module is used to determine that the new energy side protection is reliably activated when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone meet the first protection criterion.

[0021] The third calculation module is used to calculate the second amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the system side when the fault type is an interphase short circuit fault in the zone, and to calculate the second threshold of the new energy side protection action zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the interphase transition resistance and the radius of the directional impedance circle.

[0022] The second determination module is used to determine that the new energy side protection is reliably activated when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone meet the second protection criterion.

[0023] The fourth calculation module is used to calculate the current flowing through the additional impedance of the new energy side based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current when the fault type is a single-phase ground fault. It also calculates the third threshold of the protection action zone on the new energy side based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle.

[0024] The third determination module is used to determine that the new energy side protection is reliably activated when the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone meet the third protection criterion.

[0025] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing a computer program that, when executed by a processor, implements the methods described in any of the above aspects of the present invention.

[0026] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor being configured to read the executable instructions from the memory and execute the instructions to implement the method described in any of the preceding aspects of the present invention.

[0027] The present invention discloses a method and system for adaptive analysis of line backup protection. The method includes determining the fault type based on fault recording results when a fault occurs on a power transmission line containing renewable energy sources. The fault types include symmetrical faults within a zone, phase-to-phase short-circuit faults within a zone, and single-phase ground faults. When the fault type is a symmetrical fault or a phase-to-phase short-circuit fault within a zone, the fault phase current amplitude ratio and the renewable energy side protection action zone threshold are calculated based on parameter values ​​during the fault period. When the fault phase current amplitude ratio and the threshold satisfy their respective criteria, reliable operation of the renewable energy side protection is determined. When the fault type is a single-phase ground fault, the current flowing through the renewable energy side's additional impedance and the renewable energy side protection action zone threshold are calculated based on parameter values ​​during the fault period. When both satisfy the corresponding criteria, reliable operation of the renewable energy side protection is determined. This method and system clearly define the correct operation area of ​​the relay protection for the transmission line, providing a basis for improving relay protection principles and selecting devices, and has significant engineering implications for the future safe operation of the power grid. Attached Figure Description

[0028] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0029] Figure 1 A flowchart of a line backup protection adaptive analysis method according to a preferred embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the boundary point of the measured impedance on the new energy side when a symmetrical fault occurs in the area of ​​a new energy transmission line according to a preferred embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of the boundary point of the measured impedance on the new energy side when a phase-to-phase short-circuit fault occurs in the area of ​​a new energy transmission line according to a preferred embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram of the boundary point of the measured impedance on the new energy side when a single-phase ground fault occurs on a new energy transmission line according to a preferred embodiment of the present invention.

[0033] Figure 5(a) is a simulation diagram of phase-to-phase short-circuit fault under the first short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0034] Figure 5(b) is a simulation diagram of phase-to-phase short-circuit fault under the second short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0035] Figure 5(c) is a simulation diagram of phase-to-phase short-circuit fault under the third short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0036] Figure 6(a) is a simulation diagram of a single-phase grounding fault under the first short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0037] Figure 6(b) is a simulation diagram of a single-phase ground fault under the second short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0038] Figure 6(c) is a simulation diagram of a single-phase ground fault under the third short-circuit capacity ratio according to a preferred embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of the line backup protection adaptability analysis system according to a preferred embodiment of the present invention;

[0040] Figure 8 This is a schematic diagram of the structure of an electronic device according to a preferred embodiment of the present invention. Detailed Implementation

[0041] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0042] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning. Detailed Implementation

[0044] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0045] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0046] Exemplary methods

[0047] Figure 1 This is a flowchart of a line backup protection adaptability analysis method according to a preferred embodiment of the present invention. Figure 1 As shown, the line backup protection adaptability analysis method described in this preferred embodiment starts from step 101.

[0048] In step 101, when a fault occurs in the power transmission line of a power system containing new energy sources, the fault type is determined based on the fault recording results. The fault type includes symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults.

[0049] In this preferred embodiment, when the fault location and transition resistance of the renewable energy transmission line are known, the ratio of fault current amplitudes on both sides and the amplitude of the additional impedance on the renewable energy side decrease as the renewable energy capacity increases. When a fault occurs within the zone, the protection will operate correctly when the amplitude of the additional impedance decreases to the measured impedance on the renewable energy side and falls within the directional circle. The measured impedance falling on the directional circle is the boundary point between operation and non-operation. Therefore, distinguishing different fault types within the zone becomes a prerequisite for determining the correct operating area of ​​the relay protection. Existing technologies already have relatively mature methods for determining fault types based on fault recording results, which will not be elaborated upon here.

[0050] In step 102, the radius of the directional impedance circle is calculated based on the custom distance I protection setting value and the total impedance of the sending line.

[0051] Preferably, the radius of the directional impedance circle is calculated based on the custom distance I-section protection setting value and the total impedance of the transmitting line. The calculation formula is as follows:

[0052]

[0053] In the formula, Where k is the radius of the directional impedance circle, and k0 is the setting value for distance I-section protection, which is a percentage of the total length of the transmitting line. This represents the total impedance of the outgoing line.

[0054] In this preferred embodiment, the distance I protection setting value k0 is a user-defined value, which is a percentage of the total length of the outgoing line. Typically, k0 is set to 80%, at which point the radius of the directional impedance circle is 0.4. |

[0055] In step 103, when the fault type is a symmetrical fault within the zone, the first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the system side. The first threshold of the new energy side protection operation zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the currents on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle. The first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the system side. The first threshold of the new energy side protection operation zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the currents on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle.

[0056] Preferably, when the fault type is a symmetrical fault within the zone, the first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side of the line and the measured current of the fault phase on the line system side. Furthermore, the first threshold value of the new energy side protection operation zone is calculated based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the phase difference of the currents on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle. Wherein:

[0057] The formula for calculating the first amplitude ratio AR1 of the fault phase current is:

[0058]

[0059] In the formula, and The fault phases are located on the new energy side and the system side of the line, respectively. Phase current measurement ∈{A, B, C};

[0060] The formula for calculating the first threshold T1 of the new energy side protection action zone is:

[0061]

[0062]

[0063] In the formula, This is the first transition parameter. R is the positive sequence impedance from the new energy side protection device to the short circuit point. g For the transition resistance, θ L θ is the line impedance angle, and θ1 is the first phase difference of the current on both sides of the fault phase.

[0064] In step 104, when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone satisfy the first protection criterion, the new energy side protection is determined to be reliably activated.

[0065] Preferably, when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone satisfy the first protection criterion, the new energy side protection is determined to operate reliably, wherein the expression of the first protection criterion is:

[0066] .

[0067] Figure 2 This is a schematic diagram of the boundary points of the measured impedance on the renewable energy side when a symmetrical fault occurs within the area of ​​a renewable energy transmission line according to a preferred embodiment of the present invention. Figure 2 As shown, when a symmetrical fault occurs within the area of ​​the new energy transmission line, let the measured impedance on the new energy side be... If the faulty phase is phase A, then the coordinates of the boundary point D on the direction circle can be expressed as:

[0068]

[0069] In the formula, and These are the measured currents of the faulty phase A on the new energy side and the system side of the line, respectively;

[0070] The expression for the circular tuning equation of directional impedance is as follows:

[0071]

[0072] In the formula, x and y are the abscissa and ordinate of a point on the directional impedance circle, respectively;

[0073] Substituting the coordinates of boundary point D into the directional impedance circular tuning equation, we can obtain:

[0074]

[0075] Since the above equation is derived from boundary point D, the following inequality must be satisfied for the new energy side distance protection to operate reliably:

[0076]

[0077] When the faulty phase is any one of the three phases, that is, when the first criterion AR1≤T1 is satisfied, the distance protection on the new energy side can operate reliably.

[0078] In step 105, when the fault type is an interphase short-circuit fault within the zone, the second amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the system side, and the second threshold of the new energy side protection action zone is calculated based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the interphase transition resistance, and the radius of the directional impedance circle.

[0079] Preferably, when the fault type is an intra-phase short-circuit fault, the second amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side of the line and the measured current of the fault phase on the line system side. The second threshold of the new energy side protection operation zone is calculated based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the phase difference of the currents on both sides of the fault phase, the phase-to-phase transition resistance, and the radius of the directional impedance circle. This includes:

[0080] The formula for calculating the second amplitude ratio AR2 of the fault phase current is:

[0081]

[0082] The formula for calculating the second threshold T2 of the new energy side protection action zone is:

[0083]

[0084]

[0085] In the formula, 2 is the second transition parameter, R ph θ2 is the phase transition resistance, and θ2 is the second phase difference between the currents on both sides of the fault phase.

[0086] In step 106, when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone satisfy the second protection criterion, the new energy side protection is determined to be reliably activated.

[0087] Preferably, when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone satisfy the second protection criterion, the new energy side protection is determined to operate reliably, wherein the expression for the second protection criterion is:

[0088] .

[0089] Figure 3 This is a schematic diagram of the boundary points of the measured impedance on the renewable energy side during a phase-to-phase short-circuit fault in the renewable energy transmission line according to a preferred embodiment of the present invention. Figure 3 As shown, when a phase-to-phase short-circuit fault occurs on a new energy transmission line, let the faulty phase be phase B. Then, the coordinates of the boundary point E on the direction circle can be expressed as:

[0090]

[0091] In the formula, and These are the measured currents of the faulty phase B on the new energy side and the system side of the line, respectively;

[0092] Similarly, substituting the coordinates of the boundary point E into the directional impedance circular tuning equation, we can obtain:

[0093]

[0094] Since the above equation is derived from boundary point E, the following inequality must be satisfied for the new energy side distance protection to operate reliably:

[0095]

[0096] When the faulty phase is one of the three phases, that is, when the second criterion AR2≤T2 is met, the distance protection on the new energy side can operate reliably.

[0097] In step 107, when the fault type is a single-phase ground fault, the current flowing through the additional impedance of the new energy side is calculated based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current. The third threshold of the protection operation zone on the new energy side is calculated based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle.

[0098] Preferably, when the fault type is a single-phase ground fault, the current flowing through the additional impedance on the new energy side is calculated based on the positive-sequence component of the fault phase current on the new energy side, the zero-sequence current at the fault point, the branch coefficient of the zero-sequence current on the new energy side, and the compensation coefficient of the zero-sequence current. Furthermore, the third threshold of the protection operation zone on the new energy side is calculated based on the positive-sequence impedance from the protection device on the new energy side to the short-circuit point, the line impedance angle, the phase angle difference between two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle. This includes:

[0099] Current flowing through the additional impedance on the new energy side The calculation formula is:

[0100]

[0101] In the formula, , İ f0 k and C 01 These are the fault phases on the new energy side. Positive sequence component of phase current, zero sequence current at fault point, zero sequence current compensation coefficient and zero sequence current branching coefficient on the new energy side;

[0102] The formula for calculating the third threshold T3 in the new energy side protection action zone is:

[0103]

[0104] In the formula, θ3 is the phasor 3İ f0 With phasor +(3k+1)C 01 İ f0 The phase angle difference.

[0105] In step 108, when the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone satisfy the third protection criterion, it is determined that the new energy side protection is reliably activated.

[0106] Preferably, when the current flowing through the additional impedance on the new energy side and the third threshold of the new energy side protection operation zone satisfy the third protection criterion, the new energy side protection is determined to operate reliably, wherein the expression for the third protection criterion is:

[0107] .

[0108] Figure 4 This is a schematic diagram of the boundary point of the measured impedance on the renewable energy side when a single-phase ground fault occurs on a renewable energy transmission line according to a preferred embodiment of the present invention. Figure 4 As shown, when a single-phase ground fault occurs on the new energy transmission line, let the phase with the ground fault be phase A. Then, the measured impedance on the new energy side... It can be represented as:

[0109]

[0110] In the formula, Add impedance to the new energy side, This represents the positive sequence component of the faulty phase A current on the new energy side.

[0111] The simplified formula for quantizing the additional impedance phase on the new energy side can be obtained as follows:

[0112]

[0113] according to Figure 4 The coordinates of the boundary point F located on the direction circle are:

[0114]

[0115] Substituting the coordinates of the boundary point F into the directional impedance circular tuning equation, we can obtain:

[0116]

[0117] When the faulty phase of a ground fault is one of the three phases, that is, when the third criterion is met. At that time, the distance protection on the new energy side can operate reliably.

[0118] As the above analysis shows, with the increase in renewable energy capacity, the ratio of fault current amplitude on the renewable energy side to that on the system side and the amplitude of additional impedance on the renewable energy side decrease, thus improving protection reliability. When the capacity ratio on both sides further decreases to the operating boundary, the renewable energy side protection can operate correctly. The operating performance of the renewable energy side distance protection is similar for symmetrical faults and phase-to-phase faults; the analysis will focus on phase-to-phase faults.

[0119] Figure 5(a) is a simulation diagram of phase-to-phase short-circuit fault under the first short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 5(a), when the first short-circuit capacity ratio is 1:10, the steady-state value of the additional impedance on the wind power side is 5.32-j18.15Ω, the additional impedance angle is -73.6°, the steady-state value of the measured impedance on the wind power side is 6.94-j9.0Ω, and the measured impedance trajectory on the new energy side is always outside the direction circle, and the distance protection fails to operate.

[0120] Figure 5(b) is a simulation diagram of phase-to-phase short-circuit fault under the second short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 5(b), when the second short-circuit capacity ratio is 1:5, the steady-state value of the additional impedance on the wind power side is 2.86-j8.99Ω, the additional impedance angle is -72.3°, and the steady-state value of the measured impedance on the wind power side is 4.1-j0.02Ω. The steady-state trajectory is near the boundary of the directional circle. Compared with the short-circuit capacity ratio of 1:10, the degree of deviation of the steady-state measured impedance from the directional circle is reduced.

[0121] Figure 5(c) is a simulation diagram of phase-to-phase short-circuit fault under the third short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 5(c), when the third short-circuit capacity ratio is 1:3, the steady-state value of the additional impedance on the wind power side is 1.9-j5.71Ω, the additional impedance angle is -71.5°, the steady-state value of the measured impedance on the wind power side is 2.64+j2.66Ω, the measured impedance on the new energy side falls within the direction circle, and the distance protection operates correctly.

[0122] It can be seen that as the short-circuit capacity on the system side decreases, the weak feedback effect on the new energy side decreases, the amplitude of the additional impedance on the new energy side decreases, the measured impedance gradually shifts from the fourth quadrant to the first quadrant, the probability of the distance protection on the new energy side operating correctly increases, and the reliability of the distance protection is improved.

[0123] The results of single-phase ground fault distance protection under different short-circuit capacity ratios will be analyzed next.

[0124] Figure 6(a) is a simulation diagram of a single-phase grounding fault under the first short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 6(a), when the first short-circuit capacity ratio is 1:10, the steady-state value of the additional impedance on the wind power side is 7.41-j1.18Ω, and the steady-state value of the measured impedance on the wind power side is 8.42+j8.74Ω. The measured impedance trajectory on the wind power side is always outside the directional circle, and the distance protection fails to operate.

[0125] Figure 6(b) is a simulation diagram of a single-phase ground fault under the second short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 6(b), when the second short-circuit capacity ratio is 1:5, the steady-state value of the wind power side additional impedance is 5.71-j1.33Ω, the steady-state value of the wind power side measured impedance is 6.58+j7.29Ω, and the wind power side measured impedance trajectory falls within the direction circle, which is smaller than the steady-state additional impedance amplitude when the short-circuit capacity is 1:10.

[0126] Figure 6(c) is a simulation diagram of a single-phase grounding fault under the third short-circuit capacity ratio according to a preferred embodiment of the present invention. As shown in Figure 6(c), when the third short-circuit capacity ratio is 1:3, the steady-state value of the wind power side additional impedance is 5.01-j1.54Ω, and the steady-state value of the wind power side measured impedance is 5.88+7.09Ω. The wind power side measured impedance falls within the direction circle, and the distance protection operates correctly.

[0127] It is evident that as the short-circuit capacity on the system side decreases, the amplitude of the additional impedance on the new energy side decreases, the measured impedance gradually shifts towards the directional circle, the probability of the distance protection on the new energy side operating correctly increases, and the reliability of the distance protection is improved.

[0128] The line backup protection adaptability analysis method described in this preferred embodiment first distinguishes the fault types of the system's outgoing lines. When the fault type is an intra-zone symmetrical fault or an intra-zone phase-to-phase short-circuit fault, the fault phase current amplitude ratio and the threshold of the renewable energy side protection operation zone are calculated respectively. When the fault type is a single-phase ground fault, the current flowing through the renewable energy side's additional impedance and the threshold of the renewable energy side protection operation zone are calculated respectively. When the calculation results under different fault types meet the corresponding criteria, the reliable operation of the renewable energy side protection is determined. The method and system clearly define the area where the relay protection of the outgoing lines operates correctly, which can provide a basis for the improvement of relay protection principles and device selection, and has important engineering significance for the safe operation of the future power grid.

[0129] Exemplary System

[0130] Figure 7 This is a schematic diagram of the structure of a line backup protection adaptive analysis system according to a preferred embodiment of the present invention. Figure 7 As shown, the line backup protection adaptive analysis system 700 of this preferred embodiment includes:

[0131] The fault type module 701 is used to determine the fault type based on the fault recording results when a fault occurs in the power transmission line of a power system containing new energy sources. The fault type includes symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults.

[0132] The first calculation module 702 is used to calculate the radius of the directional impedance circle based on the custom distance I protection setting value and the total impedance of the sending line.

[0133] The second calculation module 703 is used to calculate the first amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the system side when the fault type is a symmetrical fault within the zone, and to calculate the first threshold of the new energy side protection action zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the current on both sides of the fault phase, the transition resistance and the radius of the directional impedance circle.

[0134] The first determination module 704 is used to determine that the new energy side protection is reliably activated when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone meet the first protection criterion.

[0135] The third calculation module 705 is used to calculate the second amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the system side when the fault type is an interphase short circuit fault in the zone, and to calculate the second threshold of the new energy side protection action zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the interphase transition resistance and the radius of the directional impedance circle.

[0136] The second determination module 706 is used to determine that the new energy side protection is reliably activated when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone meet the second protection criterion.

[0137] The fourth calculation module 707 is used to calculate the current flowing through the additional impedance of the new energy side based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current when the fault type is a single-phase ground fault. It also calculates the third threshold of the protection operation zone on the new energy side based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle.

[0138] The third determination module 708 is used to determine that the new energy side protection is reliably activated when the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone meet the third protection criterion.

[0139] Preferably, the first calculation module 702 calculates the radius of the directional impedance circle based on the custom distance I-section protection setting value and the total impedance of the transmitting line. The calculation formula is as follows:

[0140]

[0141] In the formula, Where k is the radius of the directional impedance circle, and k0 is the setting value for distance I-section protection, which is a percentage of the total length of the transmitting line. This represents the total impedance of the outgoing line.

[0142] Preferably, when the fault type is a symmetrical fault within the zone, the second calculation module 703 calculates the first amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side of the line and the measured current of the fault phase on the line system side, and calculates the first threshold of the new energy side protection operation zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the phase difference of the currents on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle, wherein:

[0143] The formula for calculating the first amplitude ratio AR1 of the fault phase current is:

[0144]

[0145] In the formula, and The fault phases are located on the new energy side and the system side of the line, respectively. Phase current measurement ∈{A, B, C};

[0146] The formula for calculating the first threshold T1 of the new energy side protection action zone is:

[0147]

[0148]

[0149] In the formula, This is the first transition parameter. R is the positive sequence impedance from the new energy side protection device to the short circuit point. g For the transition resistance, θ L θ is the line impedance angle, and θ1 is the first phase difference of the current on both sides of the fault phase.

[0150] Preferably, the first determination module 704 determines that the new energy side protection operates reliably when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone satisfy the first protection criterion, wherein the expression of the first protection criterion is:

[0151] .

[0152] Preferably, when the fault type is an intra-phase short-circuit fault, the third calculation module 705 calculates the second amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side of the line and the measured current of the fault phase on the line system side, and calculates the second threshold of the new energy side protection operation zone based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the phase difference of the currents on both sides of the fault phase, the phase transition resistance, and the radius of the directional impedance circle, including:

[0153] The formula for calculating the second amplitude ratio AR2 of the fault phase current is:

[0154]

[0155] The formula for calculating the second threshold T2 of the new energy side protection action zone is:

[0156]

[0157]

[0158] In the formula, 2 is the second transition parameter, R ph θ2 is the phase transition resistance, and θ2 is the second phase difference between the currents on both sides of the fault phase.

[0159] Preferably, the second determination module 706 determines that the new energy side protection operates reliably when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone satisfy the second protection criterion, wherein the expression for the second protection criterion is:

[0160] .

[0161] Preferably, when the fault type is a single-phase ground fault, the fourth calculation module 707 calculates the current flowing through the additional impedance of the new energy side based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current. It also calculates the third threshold of the protection operation zone on the new energy side based on the positive sequence impedance from the protection device on the new energy side to the short-circuit point, the line impedance angle, the phase angle difference between two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle. This includes:

[0162] Current flowing through the additional impedance on the new energy side The calculation formula is:

[0163]

[0164] In the formula, , k and C 01 These are the fault phases on the new energy side. Positive sequence component of phase current, zero sequence current at fault point, zero sequence current compensation coefficient and zero sequence current branching coefficient on the new energy side;

[0165] The formula for calculating the third threshold T3 in the new energy side protection action zone is:

[0166]

[0167] In the formula, θ3 is the phasor 3İ f0 With phasor +(3k+1)C 01 İ f0 The phase angle difference.

[0168] Preferably, the third determination module 708 determines that the new energy side protection is reliably activated when the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone satisfy the third protection criterion, wherein the expression of the third protection criterion is:

[0169] .

[0170] The preferred embodiment of the line backup protection adaptive analysis system has the same steps for determining the new energy side protection action area as the line backup protection adaptive analysis method, and achieves the same technical effect, so it will not be repeated here.

[0171] Exemplary electronic devices

[0172] Figure 8 This is a schematic diagram of the structure of an electronic device according to a preferred embodiment of the present invention. Figure 8 As shown, the electronic device includes one or more processors 801 and memory 802.

[0173] The processor 801 may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0174] The memory 802 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 801 may execute the program instructions to implement the line backup protection adaptive analysis method of the various embodiments disclosed above and / or other desired functions. In one example, the electronic device may also include an input device 803 and an output device 804, these components being interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0175] In addition, the input device 803 may also include, for example, a keyboard, a mouse, etc.

[0176] The output device 804 can output various information to the outside. The output device 804 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0177] Of course, for the sake of simplicity, Figure 8 Only some of the components of the electronic device relevant to this disclosure are shown, omitting components such as buses, input / output interfaces, etc. In addition, the electronic device may include any other suitable components depending on the specific application.

[0178] Exemplary computer program products and computer-readable storage media

[0179] In addition to the methods and apparatus described above, embodiments of this disclosure may also be computer program products comprising computer program instructions that, when executed by a processor, cause the processor to perform the steps in the line backup protection adaptive analysis method according to various embodiments of this disclosure as described in the "Exemplary Methods" section of this specification.

[0180] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this disclosure. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on a user's computing device, partially on a user's computing device, as a standalone software package, partially on a user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0181] Furthermore, embodiments of this disclosure may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps in the line backup protection adaptive analysis method according to various embodiments of this disclosure as described in the "Exemplary Methods" section above.

[0182] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0183] The basic principles of this disclosure have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.

[0184] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For system embodiments, since they largely correspond to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0185] The block diagrams of devices, apparatuses, devices, and systems disclosed herein are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0186] The apparatus and methods of this disclosure may be implemented in many ways. For example, they may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order of steps for the methods is for illustrative purposes only, and the steps of the methods of this disclosure are not limited to the order specifically described above unless otherwise specifically stated. Furthermore, in some embodiments, this disclosure may also be implemented as a program recorded on a recording medium, the program including machine-readable instructions for implementing the methods according to this disclosure. Thus, this disclosure also covers recording media storing programs for performing the methods according to this disclosure.

[0187] It should also be noted that in the apparatus, devices, and methods of this disclosure, the components or steps are decomposable and / or recombinable. Such decomposition and / or recombination should be considered equivalent to the present disclosure. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0188] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method of line backup protection adaptability analysis, characterized by, The method includes: When a fault occurs on a power transmission line of a power system that includes new energy sources, the fault type is determined based on the fault recording results. The fault types include symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults. Calculate the radius of the directional impedance circle based on the custom distance I protection setting value and the total impedance of the outgoing line; When the fault type is a symmetrical fault within the zone, the first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the line system side, and the first threshold of the new energy side protection action zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the current on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle. When the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone meet the first protection criterion, the new energy side protection is determined to be reliably activated. When the fault type is an intra-phase short circuit fault, the second amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the line system side, and the second threshold of the new energy side protection action zone is calculated based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the phase transition resistance, and the radius of the directional impedance circle. When the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone meet the second protection criterion, the new energy side protection is determined to be reliable. When the fault type is a single-phase ground fault, the current flowing through the additional impedance of the new energy side is calculated based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current. The third threshold of the protection action zone on the new energy side is calculated based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle. When the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone satisfy the third protection criterion, the new energy side protection is determined to be reliably activated.

2. The method of claim 1, wherein, The radius of the directional impedance circle is calculated based on the custom distance I protection setting value and the total impedance of the transmitting line. The calculation formula is as follows: In the formula, is the directional impedance circle radius, k0 is the distance I section protection setting value, which is the percentage of the total length of the outgoing line. This represents the total impedance of the outgoing line.

3. The method according to claim 1, characterized in that, When the fault type is a symmetrical fault within the zone, the first amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the line system side. The first threshold value of the new energy side protection operation zone is then calculated based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the first phase difference of the currents on both sides of the fault phase, the transition resistance, and the radius of the directional impedance circle. Where: The formula for calculating the first amplitude ratio AR1 of the fault phase current is: In the formula, and The fault phases are respectively located on the renewable energy side and the transmission system side of the line. Phase current measurement ∈{A, B, C}; The formula for calculating the first threshold T1 of the new energy side protection action zone is: In the formula, This is the first transition parameter. R is the positive sequence impedance from the new energy side protection device to the short circuit point. g For the transition resistance, θ L θ is the line impedance angle, and θ1 is the first phase difference of the current on both sides of the fault phase.

4. The method according to claim 1, characterized in that, When the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone satisfy the first protection criterion, the new energy side protection is determined to operate reliably. The expression for the first protection criterion is: 。 5. The method according to claim 1, characterized in that, When the fault type is an intra-phase short-circuit fault, the second amplitude ratio of the fault phase current is calculated based on the measured current of the fault phase on the new energy side and the line system side. The second threshold of the new energy side protection operation zone is calculated based on the positive sequence impedance from the new energy side protection device to the short-circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the inter-phase transition resistance, and the radius of the directional impedance circle. This includes: The formula for calculating the second amplitude ratio AR2 of the fault phase current is: The formula for calculating the second threshold T2 of the new energy side protection action zone is: In the formula, R is the second transition parameter. ph θ2 is the phase transition resistance, and θ2 is the second phase difference between the currents on both sides of the fault phase.

6. The method according to claim 1, characterized in that, When the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone satisfy the second protection criterion, the new energy side protection is determined to operate reliably. The expression for the second protection criterion is: 。 7. The method according to claim 1, characterized in that, When the fault type is a single-phase ground fault, the current flowing through the additional impedance on the new energy side is calculated based on the positive-sequence component of the fault phase current on the new energy side, the zero-sequence current at the fault point, the branch coefficient of the zero-sequence current on the new energy side, and the compensation coefficient of the zero-sequence current. The third threshold of the protection operation zone on the new energy side is then calculated based on the positive-sequence impedance from the protection device on the new energy side to the short-circuit point, the line impedance angle, the phase angle difference between two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle. This threshold includes: Current flowing through the additional impedance on the new energy side The calculation formula is: In the formula, , k and C 01 These are the fault phases on the new energy side. Positive sequence component of phase current, zero sequence current at fault point, zero sequence current compensation coefficient and zero sequence current branching coefficient on the new energy side; The formula for calculating the third threshold T3 in the new energy side protection action zone is: In the formula, θ3 is phasor 3. With phasor The phase angle difference.

8. The method according to claim 1, characterized in that, When the current flowing through the additional impedance on the new energy side and the third threshold of the new energy side protection operation zone satisfy the third protection criterion, the new energy side protection is determined to operate reliably. The expression for the third protection criterion is: 。 9. A line backup protection adaptive analysis system, characterized in that, The system includes: The fault type module is used to determine the fault type based on the fault recording results when a fault occurs on the power transmission line of a power system containing new energy sources. The fault types include symmetrical faults within the area, phase-to-phase short-circuit faults within the area, and single-phase grounding faults. The first calculation module is used to calculate the radius of the directional impedance circle based on the custom distance I protection setting value and the total impedance of the outgoing line. The second calculation module is used to calculate the first amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the line system side when the fault type is a symmetrical fault within the zone, and to calculate the first threshold of the new energy side protection action zone based on the positive sequence impedance from the new energy side protection device to the short circuit point, the line impedance angle, the first phase difference of the current on both sides of the fault phase, the transition resistance and the radius of the directional impedance circle. The first determination module is used to determine that the new energy side protection is reliably activated when the first amplitude ratio of the fault phase current and the first threshold of the new energy side protection action zone meet the first protection criterion. The third calculation module is used to calculate the second amplitude ratio of the fault phase current based on the measured current of the fault phase on the new energy side and the line system side when the fault type is an interphase short circuit fault in the area, and to calculate the second threshold of the protection action zone on the new energy side based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the second phase difference of the current on both sides of the fault phase, the interphase transition resistance and the radius of the directional impedance circle. The second determination module is used to determine that the new energy side protection is reliably activated when the second amplitude ratio of the fault phase current and the second threshold of the new energy side protection action zone meet the second protection criterion. The fourth calculation module is used to calculate the current flowing through the additional impedance of the new energy side based on the positive sequence component of the fault phase current on the new energy side, the zero sequence current at the fault point, the branch coefficient of the zero sequence current on the new energy side, and the compensation coefficient of the zero sequence current when the fault type is a single-phase ground fault. It also calculates the third threshold of the protection action zone on the new energy side based on the positive sequence impedance from the protection device on the new energy side to the short circuit point, the line impedance angle, the phase angle difference between the two phasors related to the current flowing through the additional impedance on the new energy side, the transition resistance, and the radius of the directional impedance circle. The third determination module is used to determine that the new energy side protection is reliably activated when the current flowing through the additional impedance of the new energy side and the third threshold of the new energy side protection action zone meet the third protection criterion.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1-8.

11. An electronic device, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1-8.

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