Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a micro energy network optimization scheduling method which is beneficial to the economic optimization operation of a system and prevents the optimization result from being too optimistic and considers the direct load control uncertainty.
The purpose of the invention can be realized by the following technical scheme:
a micro energy network optimization scheduling method considering direct load control uncertainty comprises the following steps:
step 1: establishing a direct load control model considering uncertainty;
step 2: acquiring parameters of the micro energy network;
and step 3: establishing a power balance equation of the micro energy network and a model of the equipment;
and 4, step 4: according to a power balance equation and models of all equipment, a micro energy network robust optimization scheduling model considering direct load control uncertainty and wind and light output uncertainty is established;
and 5: converting a robust optimization scheduling model containing random parameters into a deterministic optimization model;
step 6: and solving the optimal solution of the model, and scheduling the micro energy network.
Preferably, the expression of the direct load control model considering the uncertainty in step 1 is as follows:
wherein t is 1, 2., N is the total number of scheduling periods; p
LD,tAnd P
L,tRespectively a controlled afterload demand and an original demand at a time t; x
iNumber of groups of controlled loads for period i; p
C,iFor the power of each set of controlled loads during period i,
the random parameter represents that each group of controlled load power has uncertainty; d is the number of control periods of the controlled load; g
t-d+1-iA compensation strategy coefficient for a rebound load; c. C
t+1-iD is equal to or less than 1 when t +1-i is equal to or less than 0 otherwise; a is
0Max {1, t-d +1 }; when t is greater than or equal to d +1, a
1=max{1,t-d-h+1},a
2T-d, otherwise, a
1=0,a
20; h is the compensation time interval number corresponding to the single-time interval control strategy.
Preferably, the parameters of the micro energy grid in step 2 include grid structure parameters, energy type, unit cost information, user power demand, and renewable energy output information.
More preferably, the grid structure comprises a power grid, a renewable power generator set, a micro-combustion engine, a natural gas grid, a gas boiler, an electric gas conversion device P2G, a waste heat boiler and an energy storage device; the renewable generating set comprises a wind generating set and a photovoltaic cell; the energy storage device comprises an electricity storage device, an air storage device and a heat storage device.
More preferably, the step 3 specifically includes:
step 3-1: establishing a power balance equation comprising an electric power balance equation, a thermal power balance equation and an air power balance equation;
the electric power balance equation is concretely as follows:
wherein,
the output of the ith generator set in the time period t is I-3, I-1, 2 and 3 respectively represent three micro power supplies of wind, light and a micro combustion engine; p
ES,ch,tAnd P
ES,dis,tRespectively charging power and discharging power, P, of the electric storage device
EB,tFor the power consumption of the electric boiler, P, during a period of time t
P2G,tFor a period of t P2G power consumption of the device, P
BGEX,tAnd P
SGEX,tRespectively purchasing power from the main network and selling power to the main network for the micro energy network system in the t period;
the qi power balance equation is specifically as follows:
wherein G is
g,tThe gas purchasing power of the micro energy network in the period of t, G
P2G,tIs the gas generation power of P2G at t period G
GS,ch,tAnd G
GS,dis,tRespectively charging and discharging gas power G for gas storage equipment
L,tIn order to meet the natural gas demand of the user,
for gas consumption of micro-combustion engines, G
GB,tThe gas consumption power of the gas boiler;
the thermal power balance equation is specifically as follows:
wherein Q is
GB,tAnd Q
EB,tHeating powers of a gas boiler and an electric boiler in a period t respectively,
heating power for micro-combustion engine, Q
HS,ch,tAnd Q
HS,dis,tRespectively charging and discharging heat power, Q, of the heat storage equipment
L,tA thermal load demand for a period t;
step 3-2: establishing a model of energy conversion equipment, including a micro-gas turbine model, an electric gas conversion device model and a gas and heat boiler model;
the micro-combustion engine model expression is as follows:
in the formula:
and η
EHRespectively the power generation efficiency, the heating efficiency and the waste heat recovery efficiency of a waste heat boiler of the micro-gas turbine,
in order to achieve the heating power of the micro-combustion engine after passing through the waste heat boiler,
and
respectively the upper and lower limits of the output of the micro-combustion engine and the upper and lower limits of the climbing slope;
the electric gas conversion device model expression is as follows:
in the formula η
P2GIs the comprehensive energy conversion effect of the P2G deviceRate;
and
the upper and lower limits of the P2G device.
The expression of the gas boiler model is as follows:
in the formula ηGBFor the energy conversion efficiency, Q, of gas-fired boilersGB,maxAnd QGB,minRespectively the upper and lower limits of the output, delta Q, of the gas-fired boilerGB,max、ΔQGB,minThe upper limit and the lower limit of the climbing slope of the gas boiler are respectively set;
the electric boiler model expression is as follows:
in the formula ηEBFor the energy conversion efficiency of electric boilers, QEB,maxAnd QEB,minRespectively the upper and lower limits of the output, delta Q, of the electric boilerEB,maxAnd Δ QEB,minThe upper limit and the lower limit of the climbing slope of the electric boiler are respectively set;
step 3-3: establishing a model of energy storage equipment, including an electric energy storage equipment model, a thermal energy storage equipment model and a gas energy storage model;
the model expressions are as follows:
wherein E isS,tEnergy storage capacity for electricity, heat or gas for a period of t, ES,maxAnd ES,minRespectively the upper and lower limits of the energy storage capacity of electricity, heat or gas, tau is the self-loss rate of the stored energy of electricity, heat or gas, Pch,tAnd Pdis,tCharging and discharging power of electric, thermal or gas energy storage devices, respectively ηchAnd ηdisRespectively electric, thermal or pneumatic energy storage charge-discharge efficiency, Pch,max、Pch,min、Pdis,maxAnd Pdis,minRespectively are the upper and lower limits of the charge-discharge power of electricity, heat or gas energy storage;
the constraint formula of the energy storage equipment model is as follows:
ET=E0
wherein E is0And ETEnergy storage capacity of electricity, heat or gas at the beginning and end of a scheduling period respectively;
step 3-4: according to the output information of the renewable energy, establishing the constraint of the model, specifically:
wind or light output constraints:
wherein,
and
respectively the minimum and maximum technical output of the i-th renewable generator set,
and
respectively representing the power of the fan unit and the photovoltaic cell, P
W,tAnd P
PV,tRespectively predicting power of wind power and photovoltaic power at a time t;
abandon wind and abandon the restraint formula of light:
wherein, piWAnd piPVThe maximum allowable wind-light abandoning ratio is obtained.
Preferably, the objective function of the micro energy grid robust optimization scheduling model in step 4 is as follows:
min C=min(CE+CG+CD)
the calculation method of each item in the objective function specifically includes:
where Δ T is the optimized time interval, T is the total number of scheduling periods, CE、CGAnd CDRespectively compensating costs for electric energy interaction costs, natural gas purchase costs and controlled load interruption, PBGEX,tAnd PSGEX,tRespectively purchasing power from the main network and selling power to the main network for the micro energy network system in the t period CBE,tAnd CSE,tPrice of electricity purchased and sold, respectively, for micro-energy grid and main grid, CgasCost per unit of energy for purchasing natural gas, Gg,tThe gas purchasing power of the micro energy network in the period of t, Ccon,tThe price per unit of controlled load interruption is compensated for t periods.
Preferably, the specific steps of step 5 are:
step 5-1: constructing an uncertain set of random parameters of controlled load power, wind predicted power and light predicted power by using the (p, w) -norm uncertain set;
the expression of the (p, w) -norm uncertainty set is:
wherein, a
iIs the i-th row random parameter of the coefficient matrix, a
ikIs a
iThe k-th element of (a) the first,
is a
iThe average value of the k-th element in (c),
and
are respectively the indexes of the fluctuation amount,
and
the deviation of the maximum/minimum value of the random parameter from the mean value, respectively, i.e.
p
1,iAs an indicator of robustness, J
iIs the set of random parameters, | J, in the ith row of matrix A
iL is J
iThe number of middle elements;
the uncertain sets of the wind power prediction power random parameter, the photoelectric prediction power random parameter and the controlled load power random parameter are specifically as follows:
wherein, P
C,t、P
W,tAnd P
PV,tRespectively a controlled load power, a wind power prediction power and a photoelectric prediction power,
and
for the desired value and deviation of the controlled load power t period,
and
respectively an upper limit and a lower limit of the controlled load power deviation,
and
respectively a predicted power expected value and an actual power deviation value of the wind turbine generator in a time period t,
and
respectively a predicted expected power value and an actual power deviation value of the photovoltaic cell in a period t,
and
respectively are the upper limit and the lower limit of the deviation of the power generated by the wind turbine generator,
respectively the upper limit and the lower limit of the deviation of the power generated by the photovoltaic cell;
and
respectively predicting fluctuation indexes of the power random parameters for the wind,
and
respectively predicting power randomness for lightAn index of the amount of fluctuation of the parameter,
and
respectively are fluctuation indexes of random parameters of the controlled load power;
step 5-2: transforming a constraint condition containing random parameters and an objective function, specifically:
setting a new objective function as Z, adding a constraint Z- (C)E+CG+CD) More than or equal to 0, namely:
the new objective function is:
min Z
step 5-3: and converting uncertainty constraint in the robust optimization model into certainty constraint according to the robust linear optimization theory under the (p, w) -norm uncertainty set.
According to the robust linear optimization theory under the (p, w) -norm uncertain set, by introducing a dual variable z1(t)、q1(t,k)、z2(t) and q2(t, k), the electric power balance equation can be converted into a robust peer-to-peer model, and the expression is as follows:
wherein p is
1,t、p
2,tIn order to be an indicator of the robustness,
for the fluctuation index of the random parameter of the controlled load power, by controlling p
1,t、p
2,tAnd
is adjusted between robustness and optimality.
Will be a formula
Converting into a robust peer-to-peer model, wherein the expression is specifically as follows:
wherein p is
3In order to be an indicator of the robustness,
is an index of the amount of fluctuation, z
3、q
3,kThe new decision variables introduced for robust peer-to-peer transformation have no practical physical significance.
The wind or light output constraint formula and the wind or light abandon constraint formula also contain random parameters, and the robust equivalent formula after the robust equivalent transformation is specifically as follows:
wherein p is
4And p
5In order to be an indicator of the robustness,
and
predicting the fluctuation index of the power random parameter for the wind power,
and
predicting a power random parameter fluctuation amount index, z, for photovoltaic
4,t、z
5,t、q
4,kAnd q is
5,kFor robust pairAnd transforming the introduced new decision variables.
The robust peer-to-peer type of the wind/light abandoning constraint type is specifically as follows:
wherein p is
6And p
7In order to be an indicator of the robustness,
and
predicting the fluctuation index of the power random parameter for the wind power,
and
predicting a power random parameter fluctuation amount index, z, for photovoltaic
6、z
7、q
6,tAnd q is
7,tNew decision variables are introduced for robust peer-to-peer transformation.
Preferably, the optimal solution in step 6 is obtained by Lingo.
Compared with the prior art, the invention has the following advantages:
firstly, the invention brings the response of the demand side of the user side into the consideration range of the optimized scheduling, and the optimized result also shows that the direct load control can reduce the operation cost, thereby being beneficial to the economic optimized operation of the system.
The influence of the response uncertainty of the demand side and the uncertainty of the wind and light predicted output on the optimization result is considered at the same time, and the optimization result is prevented from being too optimistic.
And thirdly, controlling the relative value of the random parameter offset through a robustness index and controlling the size of a random parameter fluctuation interval through a fluctuation amount index by using the (p, w) -norm uncertain set used by the method. If the robustness index and the fluctuation index are too small, the operation cost is low, but the robustness is weak; if the setting is too large, the robustness is strong, but the cost is high. When the micro energy network is scheduled, a proper robustness index and a proper fluctuation index can be selected according to actual conditions, and adjustment is made between the optimality and the robustness of results.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.
The invention relates to a micro energy network optimization scheduling method considering direct load control uncertainty, which comprises the following steps as shown in figure 1:
step 1: establishing a direct load control model considering uncertainty;
step 2: acquiring parameters of the micro energy network;
and step 3: establishing a power balance equation of the micro energy network and a model of the equipment;
and 4, step 4: according to a power balance equation and models of all equipment, a micro energy network robust optimization scheduling model considering direct load control uncertainty and wind and light output uncertainty is established;
and 5: converting a robust optimization scheduling model containing random parameters into a deterministic optimization model;
step 6: and solving the optimal solution of the model through Lingo software to carry out micro energy network scheduling.
The expression of the direct load control model considering uncertainty in the step 1 is as follows:
wherein t is 1, 2., N is the total number of scheduling periods; p
LD,tAnd P
L,tRespectively a controlled afterload demand and an original demand at a time t; x
iNumber of groups of controlled loads for period i; p
C,iFor the power of each set of controlled loads during period i,
the random parameter represents that each group of controlled load power has uncertainty; d is the number of control periods of the controlled load; g
t-d+1-iA compensation strategy coefficient for a rebound load; c. C
t+1-iD is equal to or less than 1 when t +1-i is equal to or less than 0 otherwise; a is
0Max {1, t-d +1 }; when t is greater than or equal to d +1, a
1=max{1,t-d-h+1},a
2T-d, otherwise, a
1=0,a
20; h is the compensation time interval number corresponding to the single-time interval control strategy.
And the parameters of the micro energy network in the step 2 comprise grid structure parameters, energy types, unit cost information, user power requirements and renewable energy output information.
The grid structure considered in the present embodiment is shown in fig. 2, and includes a power grid, a renewable power generator set, a micro-combustion engine MT, a natural gas grid, a gas boiler GB, an electric boiler EB, an electric gas conversion device P2G, a waste heat boiler, and an energy storage device. The renewable power generation unit comprises a wind power generation unit WT and a photovoltaic cell PV, and the energy storage device comprises an energy storage device ES, an energy storage device GS and an energy storage device HS.
The step 3 specifically comprises the following steps:
step 3-1: establishing a power balance equation comprising an electric power balance equation, a thermal power balance equation and an air power balance equation;
the electric power balance equation is concretely as follows:
wherein,
the output of the ith generator set in the time period t is I-3, I-1, 2 and 3 respectively represent three micro power supplies of wind, light and a micro combustion engine; p
ES,ch,tAnd P
ES,dis,tRespectively charging power and discharging power, P, of the electric storage device
EB,tFor the power consumption of the electric boiler, P, during a period of time t
P2G,tFor a period of t P2G power consumption of the device, P
BGEX,tAnd P
SGEX,tRespectively purchasing power from the main network and selling power to the main network for the micro energy network system in the t period;
the gas power balance model specifically comprises the following steps:
wherein G is
g,tThe gas purchasing power of the micro energy network in the period of t, G
P2G,tIs the gas generation power of P2G at t period G
GS,ch,tAnd G
GS,dis,tRespectively charging and discharging gas power G for gas storage equipment
L,tIn order to meet the natural gas demand of the user,
for gas consumption of micro-combustion engines, G
GB,tThe gas consumption power of the gas boiler;
the thermal power balance model specifically comprises:
wherein Q is
GB,tAnd Q
EB,tHeating powers of a gas boiler and an electric boiler in a period t respectively,
heating power for micro-combustion engine, Q
HS,ch,tAnd Q
HS,dis,tRespectively charging and discharging heat power, Q, of the heat storage equipment
L,tA thermal load demand for a period t;
step 3-2: establishing a model of energy conversion equipment, including a micro-gas turbine model, an electric gas conversion device model and a gas and electric boiler model;
the micro-combustion engine model expression is as follows:
in the formula:
and
respectively the power generation efficiency, the heating efficiency and the waste heat recovery efficiency of a waste heat boiler of the micro-gas turbine,
in order to achieve the heating power of the micro-combustion engine after passing through the waste heat boiler,
the output upper limit and the output lower limit of the micro-combustion engine and the climbing upper limit and the climbing lower limit are set;
the electric gas conversion device model expression is as follows:
in the formula η
P2GThe overall energy conversion efficiency of the P2G plant;
and
the upper and lower limits of the P2G device.
The expression of the gas boiler model is as follows:
in the formula ηGBFor the energy conversion efficiency, Q, of gas-fired boilersGB,max、QGB,minRespectively the upper and lower limits of the output, delta Q, of the gas-fired boilerGB,max、ΔQGB,minThe upper limit and the lower limit of the climbing slope of the gas boiler are respectively set;
the electric boiler model expression is as follows:
in the formula ηEBFor the energy conversion efficiency of electric boilers, QEB,max、QEB,minRespectively the upper and lower limits of the output, delta Q, of the electric boilerEB,max、ΔQEB,minThe upper limit and the lower limit of the climbing slope of the electric boiler are respectively set;
step 3-3: establishing a model of energy storage equipment, including an electric energy storage equipment model, a thermal energy storage equipment model and a gas energy storage model;
the model expressions are as follows:
wherein E isS,tEnergy storage capacity for electricity, heat or gas for a period of t, ES,maxAnd ES,minRespectively the upper and lower limits of the energy storage capacity of electricity, heat or gas, tau is the self-loss rate of the stored energy of electricity, heat or gas, Pch,tAnd Pdis,tCharging and discharging power of electric, thermal or gas energy storage devices, respectively ηchAnd ηdisRespectively electric, thermal or gas energy storage charge-discharge efficiency, Pch,max、Pch,min、Pdis,maxAnd Pdis,minRespectively are the upper and lower limits of charge-discharge power of electric, thermal or gas energy storage;
the constraint formula of the energy storage equipment model is as follows:
ET=E0
wherein E is0And ETEnergy storage capacity of electricity, heat or gas at the beginning and end of a scheduling period respectively;
step 3-4: according to the output information of the renewable energy, establishing the constraint of the model, specifically:
wind or light output constraints:
wherein,
and
respectively the minimum and maximum technical output of the i-th renewable generator set,
and
respectively representing the power of the fan unit and the photovoltaic cell, P
W,tAnd P
PV,tRespectively predicting power of wind power and photovoltaic power at a time t;
abandon wind and abandon the restraint formula of light:
wherein, piWAnd piPVThe maximum allowable wind-light abandoning ratio is obtained.
The objective function of the micro energy network robust optimization scheduling model in the step 4 is as follows:
min C=min(CE+CG+CD)
the calculation method of each item in the objective function specifically includes:
where Δ T is the optimized time interval, T is the total number of scheduling periods, CE、CGAnd CDRespectively compensating costs for electric energy interaction costs, natural gas purchase costs and controlled load interruption, PBGEX,tAnd PSGEX,tRespectively purchasing power from the main network and selling power to the main network for the micro energy network system in the t period CBE,tAnd CSE,tPrice of electricity purchased and sold, respectively, for micro-energy grid and main grid, CgasCost per unit of energy for purchasing natural gas, Gg,tThe gas purchasing power of the micro energy network in the period of t, Ccon,tThe price per unit of controlled load interruption is compensated for t periods.
The specific steps of the step 5 are as follows:
step 5-1: constructing an uncertain set of random parameters of controlled load power, wind predicted power and light predicted power by using the (p, w) -norm uncertain set;
the expression of the (p, w) -norm uncertainty set is:
wherein, a
iIs the i-th row random parameter of the coefficient matrix, a
ikIs a
iThe k-th element of (a) the first,
is a
iThe average value of the k-th element in (c),
and
are respectively the indexes of the fluctuation amount,
and
the deviation of the maximum/minimum value of the random parameter from the mean value, respectively, i.e.
p
1,iAs an indicator of robustness, J
iIs the set of random parameters, | J, in the ith row of matrix A
iL is J
iNumber of middle elements, variable α
ikBy a robustness indicator p
1,iDetermining when the robustness indicator p
1,i=|J
iIn | the robustness of the optimization result is strongest, p
1,iThe smaller, the less robust, when p
1,iWhen 0, the model becomes a deterministic model.
The uncertain sets of the controlled load power random parameter, the wind power prediction power random parameter and the photoelectric prediction power random parameter are specifically as follows:
wherein, P
C,t、P
W,tAnd P
PV,tRespectively a controlled load power, a wind power prediction power and a photoelectric prediction power,
and
for the desired value and deviation of the controlled load power t period,
and
respectively an upper limit and a lower limit of the controlled load power deviation,
and
respectively a predicted power expected value and an actual power deviation value of the wind turbine generator in a time period t,
and
respectively a predicted expected power value and an actual power deviation value of the photovoltaic cell in a period t,
and
respectively are the upper limit and the lower limit of the deviation of the power generated by the wind turbine generator,
respectively the upper limit and the lower limit of the deviation of the power generated by the photovoltaic cell;
and
respectively predicting fluctuation indexes of the power random parameters for the wind,
and
respectively as fluctuation indexes of random parameters of the light prediction power,
and
respectively are fluctuation indexes of random parameters of the controlled load power;
step 5-2: transforming a constraint condition containing random parameters and an objective function, specifically:
setting a new objective function as Z, adding a constraint Z- (C)E+CG+CD) More than or equal to 0, namely:
the new objective function is:
min Z
step 5-3: converting uncertainty constraint in the robust optimization model into certainty constraint according to the robust linear optimization theory under the (p, w) -norm uncertainty set,
according to the robust linear optimization theory under the (p, w) -norm uncertain set, by introducing a dual variable z1(t)、q1(t,k)、z2(t) and q2(t, k), the electric power balance equation can be converted into a robust peer-to-peer model, and the expression is as follows:
wherein p is
1,t、p
2,tIn order to be an indicator of the robustness,
for the fluctuation index, p can be controlled
1,t、p
2,tAnd
is adjusted between robustness and optimality.
In the same way, the formula can also be used
Converting into a robust peer-to-peer model, wherein the expression is specifically as follows:
wherein p is
3In order to be an indicator of the robustness,
is an index of the amount of fluctuation, z
3、q
3,kThe new decision variables introduced for robust peer-to-peer transformation have no practical physical significance.
In addition, the wind or light output constraint and the wind or light curtailment constraint include random parameters, and robust equivalent transformation can be performed in the same manner.
The robust equivalence of the wind/light output constraint is specifically:
wherein p is
4、p
5In order to be an indicator of the robustness,
predicting the fluctuation index of the power random parameter for the wind power,
predicting a power random parameter fluctuation amount index, z, for photovoltaic
4,t、z
5,t、q
4,k、q
5,kThe new decision variables introduced for robust peer-to-peer transformation have no practical physical significance.
The robust peer-to-peer type of the wind/light abandoning constraint type is specifically as follows:
wherein p is
6、p
7In order to be an indicator of the robustness,
predicting the fluctuation index of the power random parameter for the wind power,
predicting a power random parameter fluctuation amount index, z, for photovoltaic
6、z
7、q
6,t、q
7,tThe new decision variables introduced for robust peer-to-peer transformation have no practical physical significance.
In this embodiment, taking the micro energy grid structure in fig. 2 as an example, the micro energy grid operation parameters are shown in table 1, and the typical winter solar wind power generation, gas, electricity and heat load prediction is shown in fig. 3. The total number of the selected scheduling time is 24 hours, the unit scheduling time is 15 minutes, and the controlled load is controlled within a period of 06: 00-24: 00. The average value of the power prediction of each group of controlled loads participating in direct load control is 5kW, the compensation coefficient of the DLC of the single-period control strategy is 222, namely compensation is carried out in three periods, and the compensation power of each period is twice the reduction power of the DLC. And selecting the wind and light prediction error fluctuation proportion and the controlled load power proportion to be +/-20%.
TABLE 1
The robustness indexes of the wind and light prediction random output parameters are all 75% of the maximum value, the fluctuation index is 1, the robustness indexes of the controlled load random variables are 0%, 25%, 50%, 75% and 100%, and the fluctuation index is 0.5, the controlled load curves under different robustness indexes are obtained and are shown in the graph 4, and meanwhile, the situation that the micro-energy network does not contain DLC is considered, and the operation cost of the micro-energy network is obtained and is shown in the table 2.
TABLE 2
As can be seen from fig. 4, the robustness index of the controlled load power random parameter is increased from 0 to 75%, and as the uncertainty of the controlled load random parameter is increased, the degree of participation of the direct load control in scheduling is reduced, and the load shedding power is reduced. When the robustness index is continuously increased from 75% to 100%, the controlled load curve has no obvious change, because the robustness index limits the total deviation amount between the predicted value and the actual value of the controlled load power in the whole scheduling period, when the robustness index is increased, the influence of the randomness of the controlled load power on the optimization result is increased, and the controlled load power is reduced. Since the direct load control mainly acts on the load peak time, the optimization result of the controlled load group number in other time is 0, and the influence of changing the robustness index on the optimization result is relatively small in these time. Therefore, after the robustness index of the random variable of the controlled load power is increased to a certain degree, the robustness index is continuously increased without influencing the controlled load power.
As can be seen from table 2, the microgrid running cost is the largest when no DLC is included, and thus, the DLC participates in scheduling to reduce the running cost of the system. As the robustness indicator increases from 0 to 75%, the total cost is positively correlated with the robustness indicator. Due to the output limit of micro-combustion engines, gas boilers and other equipment and the gas purchasing quantity limit of systems, the change of the gas purchasing cost is not obvious. The power interaction cost is obviously increased because the degree of DLC participation in scheduling is reduced as the robustness index is increased, the peak load regulation cannot be effectively carried out, the power interaction cost is increased, and even if the DLC compensation cost is reduced as the robustness index is increased, the total operation cost of the system is still increased. The total cost does not change significantly as the robustness indicator increases from 75% to 100%, which is consistent with the results reflected in fig. 4.
After the uncertainty of the controlled load power participating in the direct load control is considered by the optimized scheduling method in the embodiment, the uncertainty is not considered, the degree of the direct load control participating in the scheduling is reduced, the power of load reduction is reduced, the electric energy interaction cost is increased, even if the power of load reduction is reduced, the direct load control compensation cost required to be paid to a user by a system is also reduced, and compared with the uncertainty not considered, the total running cost of the micro-energy network is still increased. That is, the power interaction cost is increased to a greater extent than the DLC compensation cost is reduced, taking into account the uncertainty, resulting in an increase in the total cost of the micro power grid. Therefore, the influence of the direct load control uncertainty on the optimization result is considered when the micro energy network is scheduled, and the method can be utilized to select a proper robustness index and a fluctuation index according to the actual situation for the uncertainty of the controlled load participating in the DLC and the uncertainty of the wind and light prediction output, and adjust the optimality and the robustness of the result.
While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.