CN106230021A - Transient rotor angle stability control method containing the regional internet electrical network of controlled inertia wind-powered electricity generation - Google Patents

Abstract

The invention discloses the transient rotor angle stability control method of a kind of regional internet electrical network containing controlled inertia wind-powered electricity generation, whether the merit angle including the two regional internet electrical networks judged containing controlled inertia wind-powered electricity generation there is oscillation step, without vibrating, continue monitoring, if there being vibration, it is judged that power transmission side generating set G_SThe equivalent active power output position relationship interval with power setting, if more than this interval, output H_Svir=H_{Svir_max}, H_Rvir=0；If less than this interval, export H_Svir=0, increase H_RvirTo inertia set point；If being positioned at this interval, then without regulation.Compared with controlling with tradition transient rotor angle stability, the present invention can be according to the meritorious output state of electromotor and Shou Bai direction, interconnected network merit angle, use corresponding inertia control method, make it effectively solve power-angle oscillation problem between the electric power generator group that the wind farm grid-connected and system failure causes, improve Power Network Transient Stability level.Interconnected network changes the inertia size of its place subregion system by wind energy turbine set, improves the transient stability of system.

Description

Transient power angle stability control method for regional interconnected power grid containing controllable inertia wind power

Technical Field

The invention relates to a transient stability control method for an interconnected power grid, in particular to a transient power angle stability control method for a regional interconnected power grid containing controllable inertia wind power, and belongs to the technical field of power generation system control.

Background

With the gradual maturity of wind power technology, the wind power integration scale is continuously increased, the influence of the wind power plant access on the power system is more and more obvious, and the power system accessed to the wind power plant has more complex characteristics in the aspect of transient power angle characteristics. By taking a variable-speed wind turbine generator as an example, through independent active power regulation, the generator can virtualize controllable inertial response to provide inertial support for a system, and the adverse effect of weakening system inertia is effectively avoided. However, a large amount of controllable virtual inertia of the variable speed wind turbine will significantly change the inertia of the generator groups at the two ends of the tie line, which may cause the power angle between the generator groups to swing violently, and change the transient stability level of the power grid, so that the safe and stable operation of the power system becomes more severe. Therefore, after the inertia is added as a control parameter, the influence of the virtual inertia of the wind turbine generator on the transient state power angle stability of the interconnected power networks in the two regions is researched, and the problem of power angle oscillation is improved by using the virtual inertia, which is another key problem of whether the control method has more practical application value and further improves the safe operation level of the controllable inertia interconnected power network.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the transient power angle stability control method of the regional interconnected power grid containing the controllable inertia wind power is provided.

The technical scheme adopted by the invention is as follows:

a transient power angle stability control method for a regional interconnected power grid containing controllable inertia wind power comprises the following steps:

step a: judging whether the power angle of the regional interconnected power grid containing the controllable inertia wind power is oscillated or not, if so, turning to the step b; if not, turning to the step a;

step b: setting a power setting interval ofSetting inertia setting range as

In the formula, P_Smt、P_RmtAre respectively a generator set G on the power transmission side_SAnd a power receiving side generator set G_RThe equivalent active power output of (2); h_SvirThe virtual moment of inertia of the wind power generation unit at the power transmission side satisfies H being more than or equal to 0_Svir≤H_{Svir_max}；H_RvirThe virtual moment of inertia of the wind power generation unit at the power receiving side satisfies H being more than or equal to 0_Rvir≤H_{Rvir_max}；H_St＝H_S+H_SvirIs the equivalent inertia time constant of the generator at the power transmission end and satisfies H_{St_min}≤H_St≤H_{St_max}；H_Rt＝H_R+H_RvirIs the equivalent inertia time constant of the generator at the receiving end and meets the requirement of H_{Rt_min}≤H_Rt≤H_{Rt_max}；H_S、H_RRespectively is the inertia time constant of the generator system at the transmitting end and the receiving end; h_{Svir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power transmission side is obtained; h_{Rvir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power receiving side is obtained; h_{st_max}And H_{st_min}Of equivalent time constants of inertia of the generator at the power supply endA maximum value and a minimum value; h_{Rt_max}And H_{Rt_min}Respectively is the maximum value and the minimum value of the equivalent inertia time constant of the power receiving end generator;

step c: if the power transmission side generator set G_SEquivalent active power output P_SmtD, turning to the step d if the position relation is larger than the power setting interval; if the power transmission side generator set G_SEquivalent active power output P_SmtIf the position relation is smaller than the power setting interval, turning to the step e, and if the power generating set G at the power transmission side_SEquivalent active power output P_SmtTurning to step f when the power is in the power setting interval;

step d: output H_Svir＝H_{Svir_max}，H_Rvir＝0；

Step e: output H_SvirIncrease H when equal to 0_RvirTo the inertia setting range;

step f: no adjustment is required.

The invention has the beneficial effects that:

compared with the traditional transient power angle stability control, the strategy of the invention can adopt a corresponding inertia adjusting method according to the active power output state of the generator and the first swing direction of the power angle of the interconnected power grid, inhibit the power angle oscillation phenomenon of the interconnected power grid during the fault and improve the transient power angle stability of the system. Under the control strategy, the inertia of the system in the sub-area where the interconnected power grid is located is flexibly changed by means of virtual inertia of the wind generating set, meanwhile, the inertia of the controllable wind generating set in other areas is coordinated, and the transient state power angle stability of the system is improved.

Drawings

The invention is further illustrated by the following figures and examples.

FIG. 1 is a flow chart of the present invention;

FIG. 2 is a diagram of a simulation topology structure of a four-machine two-area system including a wind farm in the embodiment of the present invention;

FIG. 3 is a comparison curve of power angle of the system when the front pendulum and the back pendulum both swing forward before and after virtual inertia is added to the sending end network in the embodiment of the present invention;

FIG. 4 is a comparison curve of power angle of the system when the front pendulum and the rear pendulum both swing reversely after virtual inertia is added to the sending end network in the embodiment of the present invention;

fig. 5 is a curve of the influence of virtual inertia coordination of the receiving end on the power angle of the system in the embodiment of the present invention;

FIG. 6 is a block diagram of a controlled inertia two-zone power generation system in an embodiment of the present invention;

FIG. 7 is an equivalent circuit diagram of a controllable inertia-containing two-zone power generation system according to an embodiment of the present invention;

fig. 8 is a power angle swing curve of a dual-machine system in an embodiment of the present invention;

FIG. 9 shows an example of the angular acceleration α of the present invention Equivalent inertia time constant H with power transmission end_StThe relation curve between;

FIG. 10 is a diagram illustrating the adjustment of the power-receiving side inertia H according to the embodiment of the present invention_RtRear work angular acceleration α Equivalent inertia time constant H with power transmission end_StThe relation curve between;

fig. 11 is a virtual rotation inertia control structure diagram of the power transmission side wind turbine generator system in the embodiment of the invention;

fig. 12 is a virtual rotation inertia control structure diagram of the power receiving side wind turbine generator system in the embodiment of the present invention.

Detailed Description

Example (b):

as shown in fig. 1, a transient power angle stability control method for a regional interconnected power grid including controllable inertia wind power includes the following steps:

step a: judging whether the power angle of the regional interconnected power grid containing the controllable inertia wind power is oscillated or not, if so, turning to the step b; if not, turning to the step a;

step b: setting a power setting interval ofSetting inertia setting range as

In the formula, P_Smt、P_RmtAre respectively a generator set G on the power transmission side_SAnd a power receiving side generator set G_RThe equivalent active power output of (2); h_SvirThe virtual moment of inertia of the wind power generation unit at the power transmission side satisfies H being more than or equal to 0_Svir≤H_{Svir_max}；H_RvirThe virtual moment of inertia of the wind power generation unit at the power receiving side satisfies H being more than or equal to 0_Rvir≤H_{Rvir_max}；H_St＝H_S+H_SvirIs the equivalent inertia time constant of the generator at the power transmission end and satisfies H_{St_min}≤H_St≤H_{St_max}；H_Rt＝H_R+H_RvirIs the equivalent inertia time constant of the generator at the receiving end and meets the requirement of H_{Rt_min}≤H_Rt≤H_{Rt_max}；H_S、H_RRespectively is the inertia time constant of the generator system at the transmitting end and the receiving end; h_{Svir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power transmission side is obtained; h_{Rvir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power receiving side is obtained; h_{st_max}And H_{st_min}Respectively is the maximum value and the minimum value of the equivalent inertia time constant of the generator at the power transmission end; h_{Rt_max}And H_{Rt_min}Respectively is the maximum value and the minimum value of the equivalent inertia time constant of the power receiving end generator;

step c: if the power transmission side generator set G_SEquivalent active power output P_SmtD, turning to the step d if the position relation is larger than the power setting interval; if the power transmission side generator set G_SEquivalent active power output P_SmtIf the position relation is smaller than the power setting interval, turning to the step e, and if the power generating set G at the power transmission side_SEquivalent active power output P_SmtTurning to step f when the power is in the power setting interval;

step d: output H_Svir＝H_{Svir_max}，H_Rvir＝0；

Step e: output H_SvirIncrease H when equal to 0_RvirTo the inertia setting range;

step f: no adjustment is required.

As shown in FIG. 2, the present embodiment employs a four-machine two-zone interconnection system including 2 synchronous generators G₁、G₂Active outputs are respectively P_G1＝800MW、P_G2700MW, and 2 doubly-fed wind farms of capacity 200, × 1MW, L₁And L₂The loads of zone 1 and zone 2, respectively. DFIG wind power plant_S、DFIG_RRespectively passing through bus B₅、B₁₁And accessing the network. Wherein, the synchronous generator G₁Wind power plant DFIG_SForming an area 1 which is a power transmission end; synchronous generator G₂Wind power plant DFIG_RThe region 2 is formed as a power receiving end. Setting the wind speed to be 11m/s in simulation, and considering a bus B₈When a three-phase grounding fault occurs, the fault time is 0.1s, and the virtual inertia of the wind driven generator is changed to carry out simulation check analysis, which shows that the invention can lead the two-region interconnection system to improve the transient state power angle stability of the system through flexible inertia adjustment.

Fig. 3 and 4 are power angle comparison curves of systems before and after virtual inertia is added to a wind power plant accessed to a power transmission end network. When virtual inertia is added to a doubly-fed wind power plant accessed to a power transmission end network, if the power angle initial pendulum of the system swings in the forward direction, as shown in fig. 3, the deviation of the power angle initial pendulum of the system is reduced, which indicates that the transient stability of the system is improved by adding the virtual inertia to the side; when the power angle initial pendulum of the system swings reversely, as shown in fig. 4, the deviation of the power angle initial pendulum of the system increases, which indicates that the virtual inertia added to the power transmission end is not favorable for the transient stability of the system. Therefore, when the regional unit where the wind power plant is located is a forward unit, inertial response can be virtualized through the variable-speed wind power unit in the regional power grid, and power angle oscillation of the system is suppressed; on the contrary, when the equivalent generator of the power transmission end area is used as a backward unit, the transient power angle stability of the system is reduced along with the increase of the virtual inertia of the wind power plant in the power transmission end network, and at the moment, the wind power plant should not start the virtual inertia control.

When the generator in the region where the sending end is located serves as a backward unit, the transient stability of the system is reduced by adjusting the virtual inertia in the region. In this case, fig. 5 shows the power angle swing of the system when the inertia of the wind turbine on the power receiving side is adjusted. As shown in the figure, compared with the situation without virtual inertia, the power angle head swing deviation is obviously reduced, which shows that the transient stability of the system can be effectively improved through virtual inertia coordination control; after the embodiment is adopted, the power angle stability of the system can be effectively improved through the coordination of the power transmitting side and the power receiving side.

The principle analysis of the embodiment is as follows:

after the interconnected regional system is subjected to large disturbance, if a swing instability mode of two machine groups is presented, the machine group can be divided into a power transmission side and a power receiving side according to the flow direction between the machine groups, and the machine groups are respectively set as an S machine group and an R machine group. For simplifying analysis, the machine groups on the two sides are respectively equivalent to one synchronous generator, and the interconnection area is simplified into a double-machine system model, namely a generator G_SCluster S, G, representing an interconnected regional system_RRepresenting the R cluster, the two-zone controllable inertia power generation system and the equivalent circuit thereof are shown in fig. 6 and 7, wherein a synchronous generator G is shown in the figure_SAt the power supply end, G_RIs positioned at the power receiving end. Generator G_S、G_RCan be expressed as

$\frac{2H_S}{{\mathrm{\ω}}_0}\frac{d^2{\mathrm{\δ}}_S}{{\mathrm{dt}}^2}=P_{Sm}-P_{Se}---\left(1\right)$

$\frac{2H_R}{{\mathrm{\ω}}_0}\frac{d^2{\mathrm{\δ}}_R}{{\mathrm{dt}}^2}=P_{Rm}-P_{\mathrm{Re}}---\left(2\right)$

In the formula, P_Sm、P_Rm、P_Se、P_Re、H_S、H_R、_S、_RAre respectively provided withIs G_SAnd G_RMechanical power, electromagnetic power, inertia time constant and power angle; omega₀The nominal angular velocity of the system.

G_SAnd G_RPower angle difference between_S-_RThe equations (1) and (2) are subtracted, the equation of motion of the interconnected system is

$\begin{array}{c}\frac{d^2\mathrm{\δ}}{{\mathrm{dt}}^2}=\frac{{\mathrm{\ω}}_0}{2}\[(\frac{P_{Sm}}{H_S}-\frac{P_{Rm}}{H_R})-(\frac{P_{Se}}{H_S}-\frac{P_{\mathrm{Re}}}{H_R})\]\\ =\frac{{\mathrm{\ω}}_0}{2H}(P_m-P_e)\end{array}---\left(3\right)$

Wherein,

$H=\frac{H_S{H}_R}{H_S+H_R}---\left(4\right)$

$P_m=\frac{H_R}{H_S+H_R}{P}_{Sm}-\frac{H_S}{H_S+H_R}{P}_{Rm}---\left(5\right)$

$P_e=\frac{H_R}{H_S+H_R}{P}_{Se}-\frac{H_S}{H_S+H_R}{P}_{\mathrm{Re}}---\left(6\right)$

assuming a fault period, the generator G in the dual-machine system_S、G_RThe output power is approximately 0, which can be obtained from the equation (3)

${\mathrm{\δ}}_S-{\mathrm{\δ}}_R=\frac{{\mathrm{\ω}}_0{P}_m}{2H}{t}^2---\left(7\right)$

From the formula (7), P_mPositive and negative of (2) reflect the generator G_S、G_RThe relative magnitude of the power angular acceleration during transients. If P_m>0, then, during the failure,_S-_R>0, i.e. the system power angle first pendulum positive swing, G_SReferred to as forward set, G_RIs a backward machine set; p_m<0, then, during the failure,_S-_R<0, i.e. the system power angle swing in the opposite direction, G_SThen called backward unit, G_RIs a forward machine set. During fault, G_SAnd G_RThe forward and reverse power angle rocking curves between them are shown in fig. 8.

The system enables conventional units in two regional power grids to be equivalent to the wind turbine group according to respective inertia centers, and is suitable for qualitatively analyzing the region of the interconnected systemThe equivalent inertia time constant of the power angle oscillation characteristic between the two is respectively H_St、H_Rt. In the combined formula (3), after the inertia-controllable variable-speed wind turbine generator is connected in the fault period, the power angle deviation of the interconnected two-machine system can be expressed as

$\mathrm{\&delta;}={\mathrm{\&delta;}}_S-{\mathrm{\&delta;}}_R=\frac{{\mathrm{\&omega;}}_0}{2}(\frac{P_{Smt}}{H_{St}}-\frac{P_{Rmt}}{H_{Rt}})t^2=\frac{a_{\mathrm{\&delta;}}{\mathrm{\&omega;}}_0{t}^2}{2}---\left(8\right)$

$a_{\mathrm{\&delta;}}=\frac{P_{Smt}}{H_{St}}-\frac{P_{Rmt}}{H_{Rt}}---\left(9\right)$

In the formula, P_Smt＝P_Sm+P_SmwIs a generator set G_SEquivalent mechanical power of (d); p_Rmt＝P_Rm+P_RmwIs a generator set G_REquivalent mechanical power of (d); h_St＝H_S+H_SvirIs a generator set G_SThe equivalent time constant of inertia; h_Rt＝H_R+H_RvirIs a generator set G_RThe equivalent time constant of inertia; p_Smw、H_Svir、P_Rmw、H_Rvirα mechanical power and virtual rotation inertia of wind-driven generator set at power and power receiving side Defined as the angular acceleration of the system.

From the equation (9), the angular acceleration α of the inertia two-region power generation system can be controlled The size of the two-region power generation system is closely related to inertia change of the two-region power generation system and the motion state of an equivalent generator set before system failure. Theoretically, the variable-speed wind turbine generator can virtualize inertia larger than self inertia within a wider rotation speed adjusting range, and H is not less than 0 if the virtual inertia adjusting range of the wind turbine generator is H_vir≤H_{vir_max}The rotational inertia of the access transmitting and receiving end system should satisfy

H_{St_min}≤H_St≤H_{St_max}(10)

H_{Rt_min}≤H_Rt≤H_{Rt_max}(11)

In the formula, H_{St_min}＝H_S；H_{St_max}＝H_S+H_{Svir_max}；H_{Rt_min}＝H_R；H_{Rt_max}＝H_R+H_{Rvir_max}。

In contrast to equation (7), generator G is set up with inertia as the manipulated variable_S、G_RDuring the transient state, the pendulum direction of the power angle is no longer only related to the mechanical power, and the inertia magnitude also influences the acceleration α If the wind turbine adjusts its inertia, α can be made to be α after the fault Reduce and further eliminate the power angle deviation between the two regions, which is beneficial to the transient stability of the system, otherwise α The larger the size, the more the system instability is exacerbated.

The motion state of the equivalent generator set before the system fault is considered, and the power angular acceleration α of the interconnected system is obtained according to the formula (9) Power grid inertia H of power transmission side area_StThe variation curve of (2) is shown in fig. 9.

If the fault occurs, the generator set G on the power transmission side_SActive power output of

$P_{Smt}>\frac{H_{St\_max}}{H_{Rt\_min}}{P}_{Rmt}---\left(12\right)$

Curve a in fig. 9₁-b₁-c₁Reflects the angular acceleration α of the system when the generated power of the interconnected system meets the requirement of formula (12) With H_StThe variation relationship of (a). According to curve a₁-b₁-c₁According to the change rule of (1), along with the inertia H_StContinuously increasing, system power angular acceleration α The forward direction monotonous decrease is realized, namely the inertia of the power grid in the power transmission side area is increased, so that the power angle acceleration after the system fault is reduced, and the transient state power angle stability of the system is improved. At the moment, the variable speed wind turbine generator in the side grid needs to start virtual inertia control, so that inertia support is provided for the system, and transient stability of the system is guaranteed.

If the fault occurs, the generator set G_SActive power output of

$\frac{H_{St\_max}}{H_{Rt\_\min }}{P}_{Rmt}\&le;P_{Smt}\&le;\frac{H_{St\_min}}{H_{Rt\_max}}{P}_{Rmt}---\left(13\right)$

At this time, α With H_StIs shown as curve a in FIG. 9₂-b₂-c₂As shown. According to curve a₂-b₂-c₂According to the change rule of (1), along with the inertia H_StThe continuous increase of the angular acceleration of the system is firstly reduced along the positive direction and then increased along the negative direction, namely along with G_SInertia is increased, and the transient power angle stability of the interconnected system is improved and then reduced. Wherein, in b₂Angular acceleration α of point time The transient stability of the system reaches an ideal effect. In this case, the two-sided wind motors do not need to be adjusted.

If the fault occurs, the generator set G_SActive power output of

$P_{Smt}<\frac{H_{St\_\min }}{H_{Rt\_max}}{P}_{Rmt}---\left(14\right)$

At this time, α With H_StIs shown as curve a in FIG. 9₃-b₃-c₃As shown. According to curve a₃-b₃-c₃According to the change rule of (1), along with the inertia H_StAnd the power angle acceleration of the system is increased in a reverse monotonous way continuously, namely the transient power angle stability of the system is reduced by the increase of the inertia of the sending end generator set. Therefore, as can be seen from the graph, the power transmission side wind turbine generator set cannot start the virtual inertia control. By coordinately controlling virtual inertia of wind power plants at two ends, as shown in FIG. 10, inertia H at power receiving side is increased_RtCan make curve a₃-b₃-c₃The upward translation enables the curve to pass through a zero point, so that the power angular acceleration of the system is effectively reduced, and the upper limit and the lower limit are regulated as a 'in the figure'₃-b′₃-c′₃And a'₃-b′₃-c′₃As shown, the equivalent inertia H of the power-side generator set is within the range_RtThe condition should be satisfied as

$max\left\{\begin{array}{cc}{H}_{Rt\_\min }& \frac{P_{Rmt}{H}_{St\_min}}{P_{Smt}}\end{array}\right\}<H_{Rt}<min\left\{\begin{array}{cc}{H}_{Rt\_max}& \frac{P_{Rmt}{H}_{St\_max}}{P_{Smt}}\end{array}\right\}---\left(15\right)$

Therefore, the power receiving side wind turbine set adjusts the system inertia H_RvirThe condition should be satisfied as

$max\left\{\begin{array}{cc}0& \frac{P_{Rmt}{H}_{St\_min}}{P_{Smt}}-H_R\end{array}\right\}<H_{Rvir}<min\left\{\begin{array}{cc}{H}_{Rvir\_max}& \frac{P_{Rmt}{H}_{St\_max}}{P_{Smt}}-H_R\end{array}\right\}---\left(16\right)$

According to the formulas (12), (13) and (14), the active power output of the system after the wind turbine is connected to the grid can be divided into three conditions, corresponding inertia adjusting methods are respectively adopted, and the inertia control of the power generation systems at the two ends can be described as table 1.

In conclusion, the variable speed wind turbine generator system can flexibly adjust virtual inertia according to the operation conditions of the power grid of the access area, and the transient stability of the power angle of the system is improved through the coordination of the power transmission side and the power receiving side. Fig. 11 and 12 are virtual rotation inertia control structures of the doubly-fed wind turbine generator system, wherein fig. 11 is a virtual inertia control structure of the wind turbine generator system on the power transmission side, and fig. 12 is a virtual inertia control structure of the wind turbine generator system on the power reception side.

The above-mentioned embodiments are merely illustrative and not restrictive of the scope of the invention, and any insubstantial modifications made based on the spirit of the invention are intended to fall within the scope of the invention.

TABLE 1

Claims (1)

1. A transient power angle stability control method for a regional interconnected power grid containing controllable inertia wind power is characterized by comprising the following steps: the method comprises the following steps:

step a: judging whether the power angle of the regional interconnected power grid containing the controllable inertia wind power is oscillated or not, if so, turning to the step b; if not, turning to the step a;

step b: setting a power setting interval ofSetting inertia settingsIn the range of

In the formula, P_Smt、P_RmtAre respectively a generator set G on the power transmission side_SAnd a power receiving side generator set G_RThe equivalent active power output of (2); h_SvirThe virtual moment of inertia of the wind power generation unit at the power transmission side satisfies H being more than or equal to 0_Svir≤H_{Svir_max}；H_RvirThe virtual moment of inertia of the wind power generation unit at the power receiving side satisfies H being more than or equal to 0_Rvir≤H_{Rvir_max}；H_St＝H_S+H_SvirIs the equivalent inertia time constant of the generator at the power transmission end and satisfies H_{St_min}≤H_St≤H_{St_max}；H_Rt＝H_R+H_RvirIs the equivalent inertia time constant of the generator at the receiving end and meets the requirement of H_{Rt_min}≤H_Rt≤H_{Rt_max}；H_S、H_RRespectively is the inertia time constant of the generator system at the transmitting end and the receiving end; h_{Svir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power transmission side is obtained; h_{Rvir_max}The maximum value of the virtual moment of inertia of the wind turbine generator set at the power receiving side is obtained; h_{st_max}And H_{st_min}Respectively is the maximum value and the minimum value of the equivalent inertia time constant of the generator at the power transmission end; h_{Rt_max}And H_{Rt_min}Respectively is the maximum value and the minimum value of the equivalent inertia time constant of the power receiving end generator;

step c: if the power transmission side generator set G_SEquivalent active power output P_SmtD, turning to the step d if the position relation is larger than the power setting interval; if the power transmission side generator set G_SEquivalent active power output P_SmtIf the position relation is smaller than the power setting interval, turning to the step e, and if the power generating set G at the power transmission side_SEquivalent active power output P_SmtTurning to step f when the power is in the power setting interval;

step d: output H_Svir＝H_{Svir_max}，H_Rvir＝0；

Step e: output H_SvirIncrease H when equal to 0_RvirTo the inertia setting range;

step f: no adjustment is required.