CN105514956A - Ground distance relay and action method and device - Google Patents

Abstract

The invention discloses an action method and device for a distance relay, and a distance relay that responds to a single-phase ground short circuit, wherein the method includes the following steps: obtaining the comparative amount of the action criterion; calculating θ ₁ , θ ₂ and θ ₃ respectively; judging 270 ^° <θ ₁ <360 ^° , 270 ^° <θ ₂ <360 ^° and 270 ^° <θ ₃ <360 ^° are true; when 270 ^° <θ ₁ <360 ^° , 270 ^° <θ ₂ <360 ^° and 270 ^° < When θ ₃ <360 ^° , a signal to operate the ground distance relay is generated. The phase comparison criterion of the invention is simple and has high reliability, and the grounding distance relay has a strong anti-transition resistance capability, and can automatically distinguish faulty phases.

Description

A ground distance relay and its operating method and device

technical field

The invention relates to the field of power system transmission line protection, in particular to a grounding distance relay, an operating method and a device.

Background technique

Distance protection is widely used in power system line protection, and distance relay is the measuring element in distance protection. The impedance (distance) relay reflects the distance of the short-circuit point of the power system. If the short-circuit point falls within the protection zone, the distance relay will act; otherwise, it will not act. There are many types of distance relays for different applications. According to the reaction short circuit type, it can be divided into: ground distance relay and phase distance relay.

When a grounding short circuit occurs in the power system, the grounding resistance is relatively large. Therefore, it is hoped that the grounding distance relay has a relatively large allowable transition resistance capability.

Patent application CN200410024016 proposes a ground distance relay, which has good performance and relatively large allowable transition resistance capability. But there are also disadvantages: the calculation of the phase comparison criterion is more complicated and the reliability is poor.

Contents of the invention

Therefore, the technical problem to be solved by the embodiments of the present invention is that the calculation of the phase comparison criterion of the grounding distance relay in the prior art is complicated.

For this reason, a kind of ground distance relay operation method of the embodiment of the present invention comprises the following steps:

Obtain the comparison quantity of the action criterion, the comparison quantity of the action criterion includes the bus voltage phasor of the phase bus voltage where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

Calculate θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

Judge respectively whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are true;

When 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°, a signal for operating the ground distance relay is generated.

Preferably, the compensation voltage vector The calculation formula is:

in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

A grounding distance relay operating device according to an embodiment of the present invention includes:

The acquisition unit is used to acquire the comparison quantity of the action criterion, and the comparison quantity of the action criterion includes the bus voltage phasor of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

Calculation unit for calculating θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

Judgment unit, used to respectively judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established;

The action signal generating unit is used to generate a signal for operating the grounding distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°.

Preferably, the compensation voltage vector The calculation formula is:

in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

A grounding distance relay according to an embodiment of the present invention includes:

Potential transformer for receiving three-phase voltage and The three-phase voltage and Convert it into a voltage suitable for the A/D converter and output it;

Current/Voltage Converter for receiving three-phase current and The three-phase current and Convert it into a voltage suitable for the A/D converter and output it;

The A/D converter is used to convert the received voltage output by the voltage transformer and the current/voltage converter into a digital quantity and output it;

The processor includes a grounding distance relay operating device, and the grounding distance relay operating device includes:

An acquisition unit, configured to acquire an action criterion comparison quantity according to the digital quantity output by the A/D converter, and the action criterion comparison quantity includes the phase bus voltage phasor where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

Calculation unit for calculating θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

Judgment unit, used to respectively judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established;

The action signal generating unit is used to generate a signal for operating the grounding distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°.

Preferably, the compensation voltage vector The calculation formula is:

in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

The technical scheme of the embodiment of the present invention has the following advantages:

1. The grounding distance relay operation method and device provided in the embodiment of the present invention, by obtaining the bus voltage phasor of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector The comparison of the action criterion of 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° is established, and the phase The comparison criterion is simple and the reliability is high.

2. The grounding distance relay provided by the embodiment of the present invention not only has a simple phase comparison criterion and high reliability, but also has a strong anti-transition resistance capability, and has a phase selection function and a function of automatically distinguishing a faulty phase.

Description of drawings

In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the accompanying drawings that need to be used in the description of the specific embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention , for those skilled in the art, other drawings can also be obtained according to these drawings on the premise of not paying creative work.

Fig. 1 is the flow chart of a specific example of the action method of the grounding distance relay in Embodiment 1 of the present invention;

Fig. 2 is a functional block diagram of a specific example of the grounding distance relay operating device in Embodiment 2 of the present invention;

Fig. 3 is a functional block diagram of a specific example of a grounding distance relay in Embodiment 3 of the present invention;

Fig. 4 is a schematic diagram of the power system;

Figure 5(a) is a phasor diagram of short-circuit voltage in the opposite direction;

Figure 5(b) shows the phasor relationship diagram of the short-circuit voltage in the positive direction area;

Figure 5(c) shows the phasor relationship diagram of the short-circuit voltage at the end of the protection zone in the forward direction;

Figure 5(d) shows the phasor relationship diagram of short-circuit voltage outside the positive direction;

Figure 6(a) is a diagram of the relationship between the zero-sequence current and the negative-sequence current of the non-fault phase;

Figure 6(b) is the relationship between the zero-sequence current and the negative-sequence current of the non-fault phase.

detailed description

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The technical features involved in different embodiments of the present invention described below may be combined with each other as long as they do not constitute a conflict with each other.

Example 1

This embodiment provides an action method for a ground distance relay, for example applied to a ground distance relay, as shown in Figure 1, including the following steps:

S1. Obtain the comparative amount of the action criterion, which includes the voltage phasor of the busbar voltage of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

S2. Calculate θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

S3. Determine whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are true; when 270°<θ ₁ <360°, 270°<θ ₂ <360 ° and 270°<θ ₃ <360°, go to step S4; otherwise, go to step S5.

S4. Generate a signal for actuating the ground distance relay.

S5. Generate a signal for inactivating the ground distance relay.

Preferably, the compensation voltage vector The calculation formula is:

in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

The above distance relay action method, by obtaining the bus voltage phasor of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector The comparison of the action criterion of 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° is established, and the phase The comparison criterion is simple and the reliability is high.

Example 2

Corresponding to the above-mentioned embodiment 1, this embodiment provides a grounding distance relay operating device, as shown in Figure 2, including:

The acquisition unit 41 is used to acquire the comparison quantity of the action criterion, and the comparison quantity of the action criterion includes the bus voltage phasor of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

Calculation unit 42, used to calculate θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

A judging unit 43, configured to judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established respectively;

The action signal generation unit 44 is configured to generate a signal for operating the ground distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°.

Preferably, the compensation voltage vector The calculation formula is:

in, Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

The above-mentioned distance relay operating device, by obtaining the phase bus voltage phasor of the grounding distance relay zero sequence current phasor negative sequence current phasor and the compensation voltage vector The comparison of the action criterion of 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° is established, and the phase The comparison criterion is simple and the reliability is high.

Example 3

This embodiment provides a ground distance relay, as shown in Figure 3, including:

Voltage transformer 1, used to receive three-phase voltage and The three-phase voltage and Convert into a voltage suitable for the A/D converter 3 and output it;

Current/voltage converter 2 for receiving three-phase current and The three-phase current and Convert into a voltage suitable for the A/D converter 3 and output it;

The A/D converter 3 is used to convert the received voltage output by the voltage transformer 1 and the current/voltage converter 2 into a digital quantity and output it;

The processor 4 includes a grounding distance relay operating device, and the grounding distance relay operating device includes:

The acquisition unit is used to acquire the comparison quantity of the action criterion according to the digital quantity output by the A/D converter 3, and the comparison quantity of the action criterion includes the bus voltage phasor of the phase bus voltage where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c;

Calculation unit for calculating θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas:

Judgment unit, used to respectively judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established;

The action signal generating unit is used to generate a signal for operating the grounding distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°.

Preferably, the compensation voltage vector The calculation formula is:

in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.

As shown in Figure 3, the ground distance relay inputs three-phase voltage and three-phase current and three-phase voltage and Converted by voltage transformer 1 into a voltage suitable for A/D converter 3; three-phase current and Converted by the current/voltage converter 2 into a voltage suitable for the A/D converter 3; the A/D converter 3 converts the analog quantities corresponding to the three-phase voltage and the three-phase current into digital quantities, and then transmits them to the processor 4 for processing The device 4 calculates the action criterion of the grounding distance relay. When the action criterion is established, the grounding distance relay outputs an action signal; otherwise, it outputs a non-action signal.

The above-mentioned grounding distance relays are set in phases, that is, the phase A grounding distance relay responds to the phase A grounding short circuit, the phase B grounding distance relay responds to the B phase grounding short circuit, and the phase C grounding distance relay responds to the C phase grounding short circuit. Each phase-to-ground distance relay has 4 input values, and each phase-to-ground distance relay has three-phase voltage and three-phase current and Form four action criterion comparison quantities, namely:

Phase A:

Phase B:

Phase C:

The grounding distance relay action criterion is: calculation When θ ₁ , θ ₂ , θ ₃ are all greater than 270° and less than 360°, the grounding distance relay will act; otherwise, it will not act.

The following shows that the grounding distance relay has a strong anti-transition resistance capability in the event of a single-phase grounding short circuit, and has a phase selection function and a function of automatically identifying the faulty phase.

The power system is shown in Figure 4. Assume that the impedance angles of all impedances in the system are equal, and take A-phase ground short circuit as an example.

No matter whether the system is oscillating or not, the following relationship exists:

${\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; K</span>}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula: is the voltage at the short-circuit point of the fault phase; Z _f1 is the positive-sequence impedance of the line between the busbar and the short-circuit point.

Substituting the above formula into the compensation voltage expression, we can get:

${\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; a</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; K</span>}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; K</span>}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}$

M＝(Z _f1 -Z _zd )/Z _f1

If the impedance angle of the setting impedance Z _zd is equal to the impedance angle of Z _f1 , then M is a real number, and the phasor endpoints are on the same straight line. When short-circuit Z _zd > Z _f1 in the zone, M is a negative real number, U' _a and The endpoints of the on both sides, as shown in Figure 5(b). The calculation result of the phase A ground distance relay is that θ ₁ , θ ₂ , and θ ₃ are all greater than 270° and less than 360°, the phase A ground distance relay operates; the phase B ground distance relay and the C phase ground distance relay Evaluates to no action.

When Z _zd = Z _f1 , and The endpoints coincide together, which is the critical action state, as shown in Figure 5(c); the critical action state of the A-phase ground distance relay; the calculation result of the B-phase ground distance relay and the C-phase ground distance relay is no action.

When Z _zd < Z _f1 , that is, short-circuited outside the positive zone, M is a positive number less than 1, exist on the same side of the The endpoint falls on and between the endpoints, as shown in Figure 5(d). The calculation result of phase A ground distance relay, phase B ground distance relay and phase C ground distance relay is no action.

When a short circuit occurs in the opposite direction, and also in on the same side, but exist and Between, as shown in Figure 5(a). The calculation result of phase A ground distance relay, phase B ground distance relay and phase C ground distance relay is no action.

short circuit point to ground voltage is the sum of the zero-sequence currents on both sides of the system The voltage drop across the arc resistance _Rg :

${\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 3</span>}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; 0</span>}\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 3</span>}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}$

C _S0 ＝(Z _l0 -Z _f0 +Z _R0 )/(Z _S0 +Z _l0 +Z _R0 )

In the formula: C _S0 is the zero-sequence current distribution coefficient on the S side; Z _S0 , Z _R0 and Z _l0 are the zero-sequence impedances of the S side, R side and line L respectively; Z _f0 is the zero-sequence impedance from the measurement point to the fault point. Since it has been assumed that all impedance angles of the system are equal, C _S0 is a real number. therefore, phase with same.

judged separately with phasor It can correctly judge whether there is a short circuit in the area, and it has nothing to do with the magnitude of the arc resistance at the short circuit and the magnitude of the potential swing angle on both sides of the line.

If the system impedance angles are all equal, a single-phase ground short circuit occurs, and the negative sequence current of the fault phase is always in phase with the zero-sequence current, and The angle between them is zero. Therefore, the fault phase-to-ground distance from the relay θ ₁ is greater than 270° and less than 360°.

In the event of a single phase-to-ground short circuit, the negative sequence current of the non-faulty phase with zero sequence current The angle between them is always 120°, as shown in Figure 6(a), 6(b). The non-faulty phase-to-ground distance relay θ ₁ is less than 270°, and the non-faulty phase-to-ground distance relay will not act. It can be seen that the ground distance relay has the function of selecting the fault phase.

The ground distance relay mentioned above is only required to respond to a single-phase ground short circuit. When two-phase short circuit, three-phase short circuit and two-phase short circuit occur in the power system, the grounding distance relay will be blocked. When two-phase short circuit, three-phase short circuit and two-phase short circuit occur in the power system, the protection function will be realized by the interphase distance relay.

Apparently, the above-mentioned embodiments are only examples for clear description, rather than limiting the implementation. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And the obvious changes or changes derived therefrom are still within the scope of protection of the present invention.

Claims (6)

1. A grounding distance relay action method, is characterized in that, comprises the steps: Obtain the comparison quantity of the action criterion, the comparison quantity of the action criterion includes the bus voltage phasor of the phase bus voltage where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c; Calculate θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas: Judge respectively whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are true; When 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°, a signal for operating the ground distance relay is generated. 2. The method according to claim 1, wherein the compensation voltage vector The calculation formula is: in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor. 3. A grounding distance relay action device, characterized in that, comprising: The acquisition unit is used to acquire the comparison quantity of the action criterion, and the comparison quantity of the action criterion includes the bus voltage phasor of the phase where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c; Calculation unit for calculating θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas: Judgment unit, used to respectively judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established; The action signal generating unit is used to generate a signal for operating the grounding distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°. 4. The device according to claim 3, wherein the compensation voltage vector The calculation formula is: in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor. 5. A ground distance relay, characterized in that, comprising: Potential transformer (1) for receiving three-phase voltage and The three-phase voltage and converted into a voltage suitable for the A/D converter (3) and output; Current/Voltage Converter (2) for receiving three-phase current and The three-phase current and converted into a voltage suitable for the A/D converter (3) and output; The A/D converter (3) is used to convert the received voltage output by the voltage transformer (1) and the current/voltage converter (2) into a digital quantity and output it; The processor (4) includes a grounding distance relay operating device, and the grounding distance relay operating device includes: An acquisition unit, configured to acquire an action criterion comparison quantity according to the digital quantity output by the A/D converter (3), and the action criterion comparison quantity includes the phase bus voltage phasor where the grounding distance relay is located zero sequence current phasor negative sequence current phasor and the compensation voltage vector in Indicates the phase of the grounding distance relay, which is a, b or c; Calculation unit for calculating θ ₁ , θ ₂ and θ ₃ respectively according to the following formulas: Judgment unit, used to respectively judge whether 270°<θ ₁ <360°, 270°<θ ₂ <360° and 270°<θ ₃ <360° are established; The action signal generating unit is used to generate a signal for operating the grounding distance relay when 270°<θ ₁ <360°, 270°<θ ₂ <360°, and 270°<θ ₃ <360°. 6. The grounding distance relay according to claim 5, wherein the compensation voltage vector The calculation formula is: in, $K=\frac{Z_0-Z_1}{3Z_1},$ Z ₀ is the zero-sequence impedance per unit length of the line, Z ₁ is the positive-sequence impedance per unit length of the line, Z _zd is the setting impedance, is the phase current phasor.