CN104967120B - A kind of hybrid dynamic simulation method based on invariable power interface - Google Patents

Abstract

The present invention provides a kind of hybrid dynamic simulation method based on invariable power interface, comprises the following steps：Power system is divided into multiple subsystems；Obtain the when ordinal series of constant duration；Obtain the initial trend of subsystem；Determine the Injection Current and border busbar voltage simulation curve of border bus.During invariable power interface in the present invention ensures whole emulation, the exchange power of research power network and external electrical network is consistent with measured value, is that the practical of hybrid dynamic simulation method is laid a good foundation.

Description

A kind of hybrid dynamic simulation method based on invariable power interface

Technical field

The invention belongs to technical field of power systems, and in particular to a kind of hybrid dynamic simulation side based on invariable power interface Method.

Background technology

As power network popularization and grid structure strengthen, the influence of any one disturbance is diffused into vast region, often One change is the result that a large amount of factors interweave, and the reason for making checking validity of simulation and location simulation error is extremely difficult.Pass The dynamic simulation of system is mainly in load generator operation mode set in advance and predefined failure mode, in simulation process Place one's entire reliance upon the accuracy of model and algorithm, is not in contact with real system.The inaccuracy of model or parameter is likely to result in Deviation between simulation result and real system dynamic behaviour.Meanwhile, there is the WAMS (Wide of phase measuring function Area Measurement System, WAMS) in power network widely apply can accurately catch the dynamic behaviour of power network, but Be can not be arranged on system every nook and cranny, and can not as emulation forecasting system behavior.Therefore, emulation and WAMS are surveyed Amount has respective advantage and disadvantage, and power system hybrid dynamic simulation joins together both advantages, is traditional dynamic simulation It is that systematic failures reproduction, simulating, verifying etc. need accurate contrast simulation result and measurement there is provided the interface of a measurement data As a result work provides a platform, is that the fault message that profound excavation measurement data includes in itself provides method base Plinth.

Hybrid dynamic simulation uses the outside that phasor measurement unit (Phasor Measurement Unit, PMU) is collected Signal is injected into simulation subsystem, so that power network external system is carried out into equivalence, and simulation result and WAMS is measured into progress Compare, with location simulation deviating cause, verification component parameters etc..Hybrid dynamic simulation needs that the work of external electrical network should can be embodied With can not be to meet interface requirement again, larger offset is injected to research power network, simulation process is deviateed research power network normal Operation characteristic.The implementation method of conventional hybrid dynamic simulation mainly has phase-shifting transformer method, fast reaction dynamo method, become Impedance method, V- θ nodal methods etc..These methods are substantially all consistent with PMU data by the level angle of equivalent point, work as simulation process Electric current deviation actual value is larger, equivalent to larger deviation power is filled with, and forces research power network internal power source state to occur Change.The difficulty of analysis element and device behavioral trait is added, the practical formation to hybrid dynamic simulation method hinders.

The content of the invention

In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a kind of hybrid dynamic simulation based on invariable power interface Method, forms comprehensive flexible constraint to border busbar voltage, electric current, research power network is influenceed small by interface, can fully represent Study the characteristic of power network itself.This method is laid a good foundation for the practical of hybrid dynamic simulation method.

In order to realize foregoing invention purpose, the present invention is adopted the following technical scheme that：

The present invention provides a kind of hybrid dynamic simulation method based on invariable power interface, the described method comprises the following steps：

Step 1：Power system is divided into multiple subsystems；

Step 2：Obtain the when ordinal series of constant duration；

Step 3：Increase invariable power interface at the bus of border, and obtain the initial trend of subsystem；

Step 4：Determine the Injection Current and border busbar voltage simulation curve of border bus.

In the step 1, according to layouting for phasor measurement unit, power system is divided into multiple subsystems, per height Connected between system by border bus, the border bus is the bus for installing phasor measurement unit.

The step 2 specifically includes following steps：

Step 2-1：Information is injected by the collection border bus information and subsystem of phasor measurement unit constant duration, The border bus information includes the voltage magnitude and voltage phase angle of border bus, and the subsystem injects packet enclosed tool system Inject active power and reactive power；

Step 2-2：Border bus information and subsystem the injection information of collection are pre-processed, if time series is {t₁,t₂,…,t_N, then the when ordinal series of corresponding constant duration is { y₁,y₂,…,y_N, data in ordinal series when N is represented Number, is divided into following two situations：

If 1) there is shortage of data point when in ordinal series, using difference method to data missing point y_iPolishing is carried out, is had：

In formula (1), y_i-1The complete point of the i-th -1 data, y in ordinal series during expression_i+1I+1 number in ordinal series during expression According to complete point, t_i-1Represent data completely point y_i-1Corresponding time, t_i+1Represent data completely point y_i+1Corresponding time, t_iRepresent Shortage of data point y_iThe corresponding time；

2) for when ordinal series in any data, if it is more than 3 times of its front and rear 2 statistical average, the data are Data error point, is designated as y_j, data error point y is removed using the method for average value_jIn burr and mutation, obtain smoothed curve, y_jIt is expressed as：

In formula (2), y_j-1The non-error dot of -1 data of jth, y in ordinal series during expression_j+1Jth+1 in ordinal series during expression The non-error dot of data, t_j-1Represent the non-error dot j-1 of data corresponding times, t_j+1When representing that the non-error dot j+1 of data is corresponding Between, t_jRepresent data error point y_jThe corresponding time.

In the step 3, first increase invariable power interface, the initial injection active power of invariable power interface at the bus of border Inject active power with the subsystem gathered by phasor measurement unit consistent, the initial injection reactive power of invariable power interface and It is consistent that the subsystem gathered by phasor measurement unit injects reactive power；Subsystem is obtained using interior Optimal Power Flow algorithm Initial trend so that initial trend is approached with phasor measurement unit record ripple initial point voltage, phasor measurement unit record ripple initial point For when ordinal series in first data point.

The initial trend of subsystem is optimized by object function, is had：

In formula (3), u represents to control variable, including the active power output of generator and the idle of generator to exert oneself；X represents to treat Try to achieve state variable, including voltage magnitude and voltage phase angle；v_lThe measurement voltage of l-th of border bus is represented,Represent l-th The initial voltage of border bus, M represents the number of subsystem border bus；

The corresponding constraints of object function include equality constraint and inequality constraints condition, equality constraint and Inequality constraints condition is expressed as：

G (u, x)=0 (4)

h(u,x)≤0 (5)

In formula (4) and (5), g (u, x) represents equality constraint, and h (u, x) represents inequality constraints.

The step 4 specifically includes following steps：

Step 4-1：Set emulation initial time T=0, and according to when ordinal series time interval set simulation step length；

Step 4-2：Emulated using trapezoidal integration algorithm, obtain Injection Current at the bus of borderIt is expressed as：

In formula (6), I_xRepresent Injection Current at the bus of borderReal part, I_yRepresent Injection Current at the bus of borderVoid Portion；And have：

In formula (7) and (8), P represents that the subsystem gathered by phasor measurement units injects active power, and Q represents to pass through The subsystem injection reactive power of phasor measurement units collection, S represents power reference value；Border busbar voltageIt is expressed as：

In formula (9), V_xRepresent border busbar voltageReal part, V_yRepresent border busbar voltageImaginary part；

Step 4-3：Border busbar voltage simulation curve is obtained by hybrid dynamic simulation.

Compared with prior art, the beneficial effects of the present invention are：

The hybrid dynamic simulation method based on invariable power interface that the present invention is provided, it is multiple by the way that power system is divided into Subsystem, and obtain the when ordinal series of constant duration；After the initial trend for obtaining subsystem, the injection electricity of border bus is obtained Stream and border busbar voltage simulation curve.During invariable power interface ensures whole emulation, the exchange of research power network and external electrical network Power is consistent with measured value, is that the practical of hybrid dynamic simulation method is laid a good foundation.

Brief description of the drawings

Fig. 1 is the hybrid dynamic simulation method flow diagram based on invariable power interface in the embodiment of the present invention；

Fig. 2 is subsystem and border bus graph of a relation in the embodiment of the present invention.

Embodiment

The present invention is described in further detail below in conjunction with the accompanying drawings.

Such as Fig. 1, the present invention provides a kind of hybrid dynamic simulation method based on invariable power interface, and methods described includes following Step：

Step 1：Power system is divided into multiple subsystems；

Step 2：Obtain the when ordinal series of constant duration；

Step 3：Increase invariable power interface at the bus of border, and obtain the initial trend of subsystem；

Step 4：Determine the Injection Current and border busbar voltage simulation curve of border bus.

In the step 1, according to layouting for phasor measurement unit, power system is divided into multiple subsystems, per height Connected between system by border bus, the border bus is the bus for installing phasor measurement unit.

The step 2 specifically includes following steps：

Step 2-1：Information is injected by the collection border bus information and subsystem of phasor measurement unit constant duration, The border bus information includes the voltage magnitude and voltage phase angle of border bus, and the subsystem injects packet enclosed tool system Inject active power and reactive power；

Step 2-2：Border bus information and subsystem the injection information of collection are pre-processed, if time series is {t₁,t₂,…,t_N, then the when ordinal series of corresponding constant duration is { y₁,y₂,…,y_N, data in ordinal series when N is represented Number, is divided into following two situations：

If 1) there is shortage of data point when in ordinal series, using difference method to data missing point y_iPolishing is carried out, is had：

In formula (1), y_i-1The complete point of the i-th -1 data, y in ordinal series during expression_i+1I+1 number in ordinal series during expression According to complete point, t_i-1Represent data completely point y_i-1Corresponding time, t_i+1Represent data completely point y_i+1Corresponding time, t_iRepresent Shortage of data point y_iThe corresponding time；

2) for when ordinal series in any data, if it is more than 3 times of its front and rear 2 statistical average, the data are Data error point, is designated as y_j, data error point y is removed using the method for average value_jIn burr and mutation, obtain smoothed curve, y_jIt is expressed as：

In formula (2), y_j-1The non-error dot of -1 data of jth, y in ordinal series during expression_j+1Jth+1 in ordinal series during expression The non-error dot of data, t_j-1Represent the non-error dot j-1 of data corresponding times, t_j+1When representing that the non-error dot j+1 of data is corresponding Between, t_jRepresent data error point y_jThe corresponding time.

In the step 3, first increase invariable power interface, the initial injection active power of invariable power interface at the bus of border Inject active power with the subsystem gathered by phasor measurement unit consistent, the initial injection reactive power of invariable power interface and It is consistent that the subsystem gathered by phasor measurement unit injects reactive power；Subsystem is obtained using interior Optimal Power Flow algorithm Initial trend so that initial trend is approached with phasor measurement unit record ripple initial point voltage, phasor measurement unit record ripple initial point For when ordinal series in first data point.

The initial trend of subsystem is optimized by object function, is had：

In formula (3), u represents to control variable, including the active power output of generator and the idle of generator to exert oneself；X represents to treat Try to achieve state variable, including voltage magnitude and voltage phase angle；v_lThe measurement voltage of l-th of border bus is represented,Represent l-th The initial voltage of border bus, M represents the number of subsystem border bus；

The corresponding constraints of object function include equality constraint and inequality constraints condition, equality constraint and Inequality constraints condition is expressed as：

G (u, x)=0 (4)

h(u,x)≤0 (5)

In formula (4) and (5), g (u, x) represents equality constraint, and h (u, x) represents inequality constraints.

The step 4 specifically includes following steps：

Step 4-1：Set emulation initial time T=0, and according to when ordinal series time interval set simulation step length；

Step 4-2：Emulated using trapezoidal integration algorithm, obtain Injection Current at the bus of borderIt is expressed as：

In formula (6), I_xRepresent Injection Current at the bus of borderReal part, I_yRepresent Injection Current at the bus of borderVoid Portion；And have：

In formula (7) and (8), P represents that the subsystem gathered by phasor measurement units injects active power, and Q represents to pass through The subsystem injection reactive power of phasor measurement units collection, S represents power reference value；Border busbar voltageIt is expressed as：

In formula (9), V_xRepresent border busbar voltageReal part, V_yRepresent border busbar voltageImaginary part；

Step 4-3：Border busbar voltage simulation curve is obtained by hybrid dynamic simulation.

Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention rather than its limitations, to the greatest extent The present invention is described in detail with reference to above-described embodiment for pipe, and those of ordinary skill in the art should be understood：Still The embodiment of the present invention can be modified or equivalent, and without departing from any of spirit and scope of the invention Modification or equivalent, it all should cover among scope of the presently claimed invention.

Claims (6)

1. a kind of hybrid dynamic simulation method based on invariable power interface, it is characterised in that：It the described method comprises the following steps：

Step 1：Power system is divided into multiple subsystems；

Step 2：Obtain the when ordinal series of constant duration；

Step 3：Increase invariable power interface at the bus of border, and obtain the initial trend of subsystem；

Step 4：Determine the Injection Current and border busbar voltage simulation curve of border bus.

2. the hybrid dynamic simulation method according to claim 1 based on invariable power interface, it is characterised in that：The step In 1, according to layouting for phasor measurement unit, power system is divided between multiple subsystems, each subsystem and passes through border Bus is connected, and the border bus is the bus for installing phasor measurement unit.

3. the hybrid dynamic simulation method according to claim 1 based on invariable power interface, it is characterised in that：The step 2 specifically include following steps：

Step 2-1：Information is injected by the collection border bus information and subsystem of phasor measurement unit constant duration, it is described Border bus information includes the voltage magnitude and voltage phase angle of border bus, the subsystem injection packet enclosed tool system injection Active power and reactive power；

Step 2-2：Border bus information and subsystem the injection information of collection are pre-processed, if time series is { t₁, t₂,…,t_N, then the when ordinal series of corresponding constant duration is { y₁,y₂,…,y_N, data amount check in ordinal series when N is represented, It is divided into following two situations：

If 1) there is shortage of data point when in ordinal series, using difference method to data missing point y_iPolishing is carried out, is had：

$y_i=y_{i-1}+\frac{y_{i+1}-y_{i-1}}{t_{i+1}-t_{i-1}}(t_i-t_{i-1})---\left(1\right)$

In formula (1), y_i-1The complete point of the i-th -1 data, y in ordinal series during expression_i+1I+1 data are complete in ordinal series during expression Integral point, t_i-1Represent data completely point y_i-1Corresponding time, t_i+1Represent data completely point y_i+1Corresponding time, t_iRepresent data Missing point y_iThe corresponding time；

2) for when ordinal series in any data, if it is more than 3 times of its front and rear 2 statistical average, the data are data Error dot, is designated as y_j, data error point y is removed using the method for average value_jIn burr and mutation, obtain smoothed curve, y_jTable It is shown as：

$y_j=y_{j-1}+\frac{y_{j+1}-y_{j-1}}{t_{j+1}-t_{j-1}}(t_j-t_{j-1})---\left(2\right)$

In formula (2), y_j-1The non-error dot of -1 data of jth, y in ordinal series during expression_j+1+ 1 data of jth in ordinal series during expression Non- error dot, t_j-1Represent the non-error dot j-1 of data corresponding times, t_j+1Represent the non-error dot j+1 of data corresponding times, t_j Represent data error point y_jThe corresponding time.

4. the hybrid dynamic simulation method according to claim 1 based on invariable power interface, it is characterised in that：The step In 3, first increase invariable power interface at the bus of border, the initial injection active power of invariable power interface is with passing through phasor measurement list The subsystem injection active power of member collection is consistent, and the initial injection reactive power of invariable power interface is with passing through phasor measurement unit The subsystem injection reactive power of collection is consistent；The initial trend of subsystem is obtained using interior Optimal Power Flow algorithm so that just Beginning trend is approached with phasor measurement unit record ripple initial point voltage, when phasor measurement unit record ripple initial point is first in ordinal series Individual data point.

5. the hybrid dynamic simulation method according to claim 4 based on invariable power interface, it is characterised in that：Subsystem Initial trend is optimized by object function, is had：

$\begin{array}{cc}\underset{u}{min}& f(u,x)=\underset{l\≤M}{\Σ}{(v_l-{\hat{v}}_l)}^2\end{array}---\left(3\right)$

In formula (3), u represents to control variable, including the active power output of generator and the idle of generator to exert oneself；X represents to wait to try to achieve State variable, including voltage magnitude and voltage phase angle；v_lThe measurement voltage of l-th of border bus is represented,Represent l-th of border The initial voltage of bus, M represents the number of subsystem border bus；

The corresponding constraints of object function include equality constraint and inequality constraints condition, equality constraint and Formula constraints is expressed as：

G (u, x)=0 (4)

h(u,x)≤0 (5)

In formula (4) and (5), g (u, x) represents equality constraint, and h (u, x) represents inequality constraints.

6. the hybrid dynamic simulation method according to claim 1 based on invariable power interface, it is characterised in that：The step 4 specifically include following steps：

Step 4-1：Set emulation initial time T=0, and according to when ordinal series time interval set simulation step length；

Step 4-2：Emulated using trapezoidal integration algorithm, obtain Injection Current at the bus of borderIt is expressed as：

$\stackrel{\·}{I}=I_x+{\mathrm{jI}}_y---\left(6\right)$

In formula (6), I_xRepresent Injection Current at the bus of borderReal part, I_yRepresent Injection Current at the bus of borderImaginary part；And Have：

$I_x=\frac{P\·V_x+Q\·V_y}{S\·({V_x}^2+{V_y}^2)}---\left(7\right)$

$I_y=\frac{P\·V_y-Q\·V_x}{S\·({V_x}^2+{V_y}^2)}---\left(8\right)$

In formula (7) and (8), P represents that the subsystem gathered by phasor measurement units injects active power, and Q is represented by vector The subsystem injection reactive power of measuring unit collection, S represents power reference value；Border busbar voltageIt is expressed as：

$\stackrel{\·}{V}=V_x+{\mathrm{jV}}_y---\left(9\right)$

In formula (9), V_xRepresent border busbar voltageReal part, V_yRepresent border busbar voltageImaginary part；

Step 4-3：Border busbar voltage simulation curve is obtained by hybrid dynamic simulation.