Disclosure of Invention
The invention aims to provide a power system scheduling method based on wind power active power control under the condition of considering wind power scheduling capability.
The technical solution for realizing the purpose of the invention is as follows: a power system scheduling method based on wind power active power control comprises the following steps:
step 1, calculating the active power control capability of each wind turbine in the wind power plant. Calculating three electrical quantities reflecting the active power control capability of each wind turbine in the wind power plant, namely the adjustable capacity, the adjustable speed and the fan reserve capacity, and taking the three electrical quantities as basic data of the active power control capability of the wind power plant in the step 2. The adjustable capacity of the wind turbine generator is obtained by subtracting the output power of the current period from the maximum power of the predicted wind speed of the next period, the adjusting rate is obtained by summarizing the test power change rate, and the standby capacity of the fan is obtained by calculating five percent of the adjustable capacity.
And 2, calculating the active power control capability of the wind power plant. The method comprises the steps of calculating the adjustable capacity, the adjusting rate and the wind field reserve capacity of the wind power plant, and obtaining the wind power plant by summing the parameters calculated in the step 1 by all the fans in the wind power plant. And 3, constructing a wind power constraint condition in the step 3 and constructing three parameters of a power system scheduling model based on wind power active power control in the step 4.
And 3, constructing related constraint conditions of the wind power plant. By analogy with the output constraint and the climbing rate constraint of a conventional unit, two constraint conditions of the wind power plant output constraint and the wind power plant regulation rate constraint are constructed by using two parameters of the wind power plant regulation capacity and the regulation rate. The output constraint of the wind power plant requires that the difference between the output power of the wind power plant in the next period and the output power of the wind power plant in the current period is smaller than the adjustable capacity of the wind power plant; the wind farm regulation rate constraint requires that the regulation capacity of the wind farm be less than the regulation rate.
And 4, constructing a power system scheduling model based on wind power active power control. This model targets the economic optimality of system scheduling, with costs including: the starting and stopping cost and the output cost of the conventional unit, and the output cost and the wind abandoning cost of the wind power plant. The constraints of this model include: the method comprises the following steps of (1) power balance constraint, tidal current safety constraint, hot standby constraint, conventional unit output constraint, conventional unit climbing constraint, conventional unit start-stop time constraint, conventional unit start-stop cost constraint, wind power plant output constraint and wind power plant regulation rate constraint constructed in step (3). Wherein the parameter of the wind farm spare capacity calculated in step 2 is involved in the hot spare constraint.
And 5, solving the model based on CPLEX and obtaining a scheduling scheme. Setting basic information and scenes such as grid structure, node parameters, line parameters, generator parameters and wind power plant parameters, and calculating a scheduling scheme of a power system scheduling model based on wind power active power control in the corresponding scene through a commercial CPELX solver. The scheduling scheme comprises the start-stop condition and the power output condition of the conventional unit and the wind power plant in each period.
Further, the method for calculating the active power control capability of each wind turbine in the wind farm in step 1 specifically includes:
and calculating three parameters of schedulable capacity, regulation rate and spare capacity of the single fan.
The adjustable capacity of the fan indicates that a single fan can actively participate in scheduling capacity, and a calculation formula is as follows:
in the formula, Pi,max,t+1Predicting the wind speed of the wind turbine generator i in the next periodMaximum power, Pi,tIs the output power P of the wind turbine generator i at the wind speed of the periodN,iThe rated power of the wind turbine generator i.
Secondly, the fan regulation rate is the embodiment of the regulation efficiency when a single fan participates in the scheduling, and the calculation formula is as follows:
in the formula,. DELTA.Pi,aThe power variation value of the wind turbine generator i in the a-th test is obtained; m is the total number of tests.
Thirdly, the spare capacity of the fan is the capacity which needs to be reserved when the single fan participates in scheduling, generally 5% of the adjustable capacity is taken, and the calculation formula is as follows:
in the formula,. DELTA.Pi *The adjustable capacity of the single fan is calculated by the formula (1).
Further, the method for calculating the active participation scheduling capability of the wind farm in step 2 specifically comprises the following steps:
and under the condition of the single fan parameter calculated according to the step one, calculating three parameters of the wind power plant.
The adjustable capacity of the wind power plant represents the active scheduling capacity of a single wind power plant, and the calculation formula is as follows:
in the formula, Pi,max,t+1Predicting the maximum power P of the wind turbine generator set i in the next periodi,tIs the output power P of the wind turbine generator i at the wind speed of the periodN,iIs the rated power of a wind turbine generator i, j represents the jth wind farm, njAnd the number of wind turbine sets in the wind power plant j is represented.
Secondly, the wind power plant regulation rate is the embodiment of regulation efficiency when a single wind power plant participates in scheduling, and the calculation formula is as follows:
in the formula,. DELTA.Pi,aIs the power variation value of the wind turbine generator i in the a-th test, m is the total number of tests, j represents the j-th wind power plant, njAnd the number of wind turbine sets in the wind power plant j is represented.
Thirdly, the spare capacity of the fan is the capacity which needs to be reserved when the single fan participates in scheduling, generally 5% of the adjustable capacity is taken, and the calculation formula is as follows:
in the formula,. DELTA.Pi *Capacity adjustable for a single fan, j denotes the jth wind farm, njAnd the number of wind turbine sets in the wind power plant j is represented.
Further, the construction of the relevant constraint conditions of the wind power plant in the step 3 is specifically as follows:
compared with the conventional unit, two constraints of the output constraint of the wind power plant and the regulation rate constraint of the wind power plant are obtained.
Output constraint of wind power plant
In the formula, P
j,tThe output of the wind power plant j at the moment t,
the capacity of the wind power plant can be adjusted.
Wind farm regulation rate constraint
In the formula (I), the compound is shown in the specification,
for capacity regulation of wind farms, v
jThe rate is adjusted for the wind farm.
Further, the power system scheduling model based on wind power active power control in step 4 is specifically as follows:
the model takes the economic optimization of system scheduling as a target, and the target function is as follows:
in the formula (I), the compound is shown in the specification,
and
respectively the start-stop cost of the conventional unit i,
in order to reduce the output cost of the conventional unit i,
for the output cost of the wind farm j,
the wind curtailment cost for wind farm j.
The constraint conditions of the model are power grid constraint, conventional generator constraint and wind power plant constraint, and are as follows:
power balance constraint of system
In the formula, Pi,tThe output of a conventional unit i at the moment t, Pj,tIs the output of the wind farm j at the moment t, Pd,tThe load demand of node d at time t.
② safety constraint of power flow
Pl,min≤Pl,t≤Pl,max (11)
In the formula, Pl,tIs the active power of line l at time t, Pl,minAnd Pl,maxThe upper and lower power limits of line l.
Thirdly hot standby restraint
In the formula u
i,tIs the start-stop state of the conventional unit i at the moment t,
reserving a spare for the wind turbine generator, wherein rho is a hot spare coefficient.
Output restraint of conventional unit
ui,tPi,min≤Pi≤ui,tPi,max (13)
In the formula ui,tIs the start-stop state of the conventional unit i at the moment t, Pi,minIs the minimum output, P, of the conventional unit at the moment ti,maxThe maximum output of the conventional unit at the time t.
Fifth, conventional unit climbing restraint
-Rd≤Pi,t-Pi,t-1≤Ru (14)
In the formula, RdAnd RuThe down/up climbing rate of the conventional unit.
Sixth, the start-stop time constraint of the conventional unit
Where TS and TO are the minimum off/on time.
Seventhly, the start-stop cost constraint of the conventional unit
In the formula, HiAnd JiIs the single start-up/shut-down cost of the conventional unit i.
Output constraint of wind power plant
In the formula, P
jtThe output of the wind power plant j at the moment t,
the capacity of the wind power plant can be adjusted.
Ninthly wind farm regulation rate constraint
In the formula (I), the compound is shown in the specification,
for capacity regulation of wind farms, v
jThe rate is adjusted for the wind farm.
Further, the solving model based on CPLEX and obtaining the scheduling scheme in step 5 are specifically as follows:
and (3) programming by using Matlab, and directly solving by using a commercial toolkit CPLEX because the problem is a hybrid integration planning problem to obtain the economic dispatching scheme of the electric power system based on the wind power active power control. Setting basic information and scenes such as grid structure, node parameters, line parameters, generator parameters and wind power plant parameters, and calculating a scheduling scheme of a power system scheduling model based on wind power active power control in the corresponding scene through a commercial CPELX solver. The scheduling scheme comprises the start-stop condition and the power output condition of the conventional unit and the wind power plant in each period.
Compared with the prior art, the invention has the following remarkable advantages: the method can perform economic optimization scheduling on the power system under the condition of considering the active power control of the fan, and solves the problem of high scheduling pressure of the traditional generator.
Detailed Description
The invention discloses a power system dispatching method based on wind power active power control, which is used for carrying out economic dispatching on a power system on the basis of considering that wind power has certain dispatching capability and solving the problem of high dispatching pressure of a traditional generator. The method comprises the steps of firstly calculating the active power control capability of each wind turbine in the wind power plant, and calculating the power control capability of the whole wind power plant after calculation to quantitatively obtain the adjustable capacity of the wind power plant, the adjusting rate of the wind power plant and the reserve capacity of the wind power plant. And then, according to the quantified parameters, simulating a conventional generator set to construct a power system scheduling model based on wind power active power control. And solving the model by using CPLEX and obtaining an optimal scheduling scheme of the power system with optimal economy. The method can perform economic optimization scheduling on the power system under the condition of considering the active power control of the fan.
With reference to fig. 1, the method for scheduling a power system based on wind power active power control of the present invention includes the following specific steps:
step 1, calculating the active power control capability of each wind turbine in a wind power plant, specifically as follows:
and calculating three parameters of schedulable capacity, regulation rate and spare capacity of the single fan.
The adjustable capacity of the fan indicates that a single fan can actively participate in scheduling capacity, and a calculation formula is as follows:
in the formula, Pi,max,t+1Predicting the maximum power P of the wind turbine generator set i in the next periodi,tIs the output power P of the wind turbine generator i at the wind speed of the periodN,iThe rated power of the wind turbine generator i.
Secondly, the fan regulation rate is the embodiment of the regulation efficiency when a single fan participates in the scheduling, and the calculation formula is as follows:
in the formula,. DELTA.Pi,aThe power variation value of the wind turbine generator i in the a-th test is obtained; m is the total number of tests.
Thirdly, the spare capacity of the fan is the capacity which needs to be reserved when the single fan participates in scheduling, generally 5% of the adjustable capacity is taken, and the calculation formula is as follows:
in the formula,. DELTA.Pi *The adjustable capacity of the single fan is calculated by the formula (1).
Step 2, calculating the active participation scheduling capability of the wind power plant, specifically as follows:
and under the condition of the single fan parameter calculated according to the step one, calculating three parameters of the wind power plant.
The adjustable capacity of the wind power plant represents the active scheduling capacity of a single wind power plant, and the calculation formula is as follows:
in the formula, Pi,max,t+1Predicting the maximum power P of the wind turbine generator set i in the next periodi,tIs the output power P of the wind turbine generator i at the wind speed of the periodN,iIs the rated power of a wind turbine generator i, j represents the jth wind farm, njAnd the number of wind turbine sets in the wind power plant j is represented.
Secondly, the wind power plant regulation rate is the embodiment of regulation efficiency when a single wind power plant participates in scheduling, and the calculation formula is as follows:
in the formula,. DELTA.Pi,aIs the power variation value of the wind turbine generator i in the a-th test, m is the total number of tests, j represents the j-th wind power plant, njAnd the number of wind turbine sets in the wind power plant j is represented.
Thirdly, the spare capacity of the fan is the capacity which needs to be reserved when the single fan participates in scheduling, generally 5% of the adjustable capacity is taken, and the calculation formula is as follows:
in the formula,. DELTA.Pi *Capacity adjustable for a single fan, j denotes the jth wind farm, njAnd the number of wind turbine sets in the wind power plant j is represented.
Step 3, constructing related constraint conditions of the wind power plant, which are as follows:
compared with the conventional unit, two constraints of the output constraint of the wind power plant and the regulation rate constraint of the wind power plant are obtained.
Output constraint of wind power plant
In the formula, P
tThe output of the wind power plant j at the moment t,
the capacity of the wind power plant can be adjusted.
Wind farm regulation rate constraint
In the formula (I), the compound is shown in the specification,
for capacity regulation of wind farms, v
jThe rate is adjusted for the wind farm.
Step 4, constructing a power system scheduling model based on wind power active power control, which specifically comprises the following steps:
the model takes the economic optimization of system scheduling as a target, and the target function is as follows:
in the formula (I), the compound is shown in the specification,
and
respectively the start-stop cost of the conventional unit i,
in order to reduce the output cost of the conventional unit i,
for the output cost of the wind farm j,
the wind curtailment cost for wind farm j.
The constraint conditions of the model are power grid constraint, conventional generator constraint and wind power plant constraint, and are as follows:
power balance constraint of system
In the formula, Pi,tThe output of a conventional unit i at the moment t, Pj,tIs the output of the wind farm j at the moment t, Pd,tThe load demand of node d at time t.
② safety constraint of power flow
Pl,min≤Pl,t≤Pl,max (11)
In the formula, Pl,tIs the active power of line l at time t, Pl,minAnd Pl,maxThe upper and lower power limits of line l.
Thirdly hot standby restraint
In the formula u
i,tIs the start-stop state of the conventional unit i at the moment t,
reserving a spare for the wind turbine generator, wherein rho is a hot spare coefficient.
Output restraint of conventional unit
ui,tPi,min≤Pi≤ui,tPi,max (13)
In the formula ui,tIs the start-stop state of the conventional unit i at the moment t, Pi,minIs the minimum output, P, of the conventional unit at the moment ti,maxThe maximum output of the conventional unit at the time t.
Fifth, conventional unit climbing restraint
-Rd≤Pi,t-Pi,t-1≤Ru (14)
In the formula, RdAnd RuThe down/up climbing rate of the conventional unit.
Sixth, the start-stop time constraint of the conventional unit
Where TS and TO are the minimum off/on time.
Seventhly, the start-stop cost constraint of the conventional unit
In the formula, HiAnd JiIs the single start-up/shut-down cost of the conventional unit i.
Output constraint of wind power plant
In the formula, P
j,tThe output of the wind power plant j at the moment t,
the capacity of the wind power plant can be adjusted.
Ninthly wind farm regulation rate constraint
In the formula (I), the compound is shown in the specification,
for capacity regulation of wind farms, v
jThe rate is adjusted for the wind farm.
Step 5, solving the model based on CPLEX and obtaining a scheduling scheme, which comprises the following steps:
and (3) programming by using Matlab, and directly solving by using a commercial toolkit CPLEX because the problem is a hybrid integration planning problem to obtain the economic dispatching scheme of the electric power system based on the wind power active power control. Setting basic information and scenes such as grid structure, node parameters, line parameters, generator parameters and wind power plant parameters, and calculating a scheduling scheme of a power system scheduling model based on wind power active power control in the corresponding scene through a commercial CPELX solver. The scheduling scheme comprises the start-stop condition and the power output condition of the conventional unit and the wind power plant in each period.