CN106683000A - Electric power system economical scheduling method with carbon tax considered - Google Patents

Abstract

The invention discloses an electric power system economical scheduling method with carbon tax considered. An electric power system is one of the highest carbon dioxide emission sources, and carbon emission reduction is a significant factor that needs to be considered for operations of future electric power systems. Conventional economical scheduling takes the lowest system power generation cost as a goal without taking external costs caused by system emission into account. Carbon taxes are considered in an electric power system economical scheduling model, external costs caused by carbon dioxide emission can be internalized into economic indicators of system operations, and the external costs and power generation costs are optimized in a unified manner. Electric power sources of users are tracked based on a trend tracking technology, so carbon emission intensity of the users is evaluated and carbon taxes of the users are determined. The sum of the carbon taxes of the users and the power generation total cost are taken as target functions, and optimization is carried out in the economical scheduling model. Compared with a conventional economical scheduling method, the method of the invention enables unified optimization of economies and environments, encourages electric power users to save energy and reduce emission, and reduces final power utilization costs of the users.

Description

A kind of Economic Dispatch method for considering carbon tax

Technical field

The present invention relates to electric power system dispatching and management domain, and in particular to a kind of power system economy of consideration carbon tax is adjusted Degree method.

Background technology

Carbon tax is the tax levied to CO2 emission, used as a kind of effective measures of reduction CO2 emission, carbon tax It is used widely in worldwide.Power system is one of maximum CO2 emission source, and it is not to reduce carbon emission Carry out in Operation of Electric Systems the key factor for needing to consider.Traditional economic load dispatching does not have with the minimum target of system cost of electricity-generating There is the external cost that the discharge of consideration system is caused.Carbon tax is taken into account into Economic Dispatch model, can be by the two of discharge The economic indicator of system operation is turned in the external cost that carbonoxide is caused, carries out unifying optimization with cost of electricity-generating, can be realized Economy is unified optimum with environment, reduces the final electric cost of user.

The content of the invention

Present invention aims to the deficiencies in the prior art, there is provided a kind of Economic Dispatch of consideration carbon tax Method.

The purpose of the present invention is achieved through the following technical solutions：A kind of Economic Dispatch for considering carbon tax Method, the method is comprised the following steps：

(1) user's carbon tax cost model is set up, specially：

(1.1) the carbon intensity EL of load is determined_j；

(1.2) the carbon tax cost of user is determined：By the carbon intensity EL of load_jWith loading PL_jProduct is used as the load The carbon emission amount for causing, by all load carbon emission amounts and carbon tax T_jThe sum of products as the total carbon tax cost f of user_C.I.e.：Nl is the number of system internal loading.

(2) economic load dispatching model is set up, specially：

(2.1) object function is determined：With the total carbon tax sum of the total cost of electricity-generating of system and user as object function, i.e., Minf=f_G+f_C, wherein f_GFor the cost of electricity-generating sum of all electromotors.

(2.2) constraints is determined：Power-balance constraint, branch power constraint, node voltage amplitude constraint, electromotor go out Force constraint.

(3) economic load dispatching model is solved：Economic load dispatching model is solved using prim al- dual interior point m ethod, it is determined that sending out per platform The active and idle plan of exerting oneself of motor.

Further, the step (1) is set up in user's carbon tax cost model, determines the carbon intensity EL of load_jIt is Refer to：

A. the carbon intensity EG of every generating set is determined_i；

B. power flow tracing technology is utilized, it is determined that determine the power source of each power load, by electromotor-sharing of load system Matrix number is expressed as A, A_ijRepresent i-th electromotor to j-th burden apportionment coefficient.All electromotors are to j-th load Partition coefficient sum is 1, i.e.,Wherein Ng is electromotor number；

C. the carbon intensity of load is determined：By the carbon intensity of load be set to the electromotor powered of the oriented load The weighted mean of carbon intensity, i.e.,：

Further, the step (1) is set up in user's carbon tax cost model, determines the carbon intensity EL of load_j, EL_j It is depending on the variable of electromotor output.

Further, the step (2) sets up economic load dispatching model, and the model is specifically referred to：

1. object function：

Minf=f_G+f_C

2. constraints：

A. power-balance constraint：

Wherein, P_Gi, Q_Gi, P_Di, Q_DiRespectively in node i in the active power of electromotor output, reactive power and node i The active power of load, reactive power.θ_iWith | V_i| the respectively phase angle and amplitude of node i voltage, G_ijAnd B_ijRespectively branch road The equivalent conductance and susceptance of i-j, N_bFor system node number.

B. generator output constraint：

Wherein,P _Gi ,The lower limit and the upper limit of electromotor active power of output respectively in node i,Q _Gi ,Respectively save The lower limit and the upper limit of electromotor output reactive power on point i.

C. branch power constraint：

|S_ij|≤|S_ij|^max

Wherein, | S_ij| for the apparent energy of branch road i-j, | S_ij|^maxFor the upper limit of the apparent energy of branch road i-j.

D. node voltage amplitude constraint：

|V_i|^min≤|V_i|≤|V_i|^max

Wherein, | V_i|^min, | V_i|^0axThe respectively lower limit and the upper limit of node i voltage magnitude.

Further, step (3) solves economic load dispatching model using prim al- dual interior point m ethod, needs to ask object function to variable Single order lead and led with second order.Meanwhile, in electromotor-sharing of load coefficient matrices A that step (1) is determined using power flow tracing technology In inverse matrix Z occurs^-1.In solution procedure, will be to Z^-1Derivation problem be converted to the derivation problem to original matrix Z：

Wherein, x_pFor the variable in economic load dispatching model.

Advantages of the present invention and good effect are：

1st, the inverse matrix derivation problem occurred in power flow tracing is converted into the derivation problem to original matrix by the present invention, therefore Can user's carbon tax for determining of power flow tracing add in the object function of economic load dispatching, realize to cost of electricity-generating and carbon tax into This combined optimization.

2nd, in the inventive method, elasticity of the customer charge to electricity price is considered in economic load dispatching model, customer charge both may be used Being flexible load that firm demand can also be depending on electricity price level.Therefore, when the high electromotor of carbon intensity is (as low The fired power generating unit of efficiency) when generating electricity more, system cost is higher, and user can reduce its workload demand amount.Conversely, when cleaning electricity When source generates electricity more, system cost is relatively low, and user can improve its workload demand amount.In this way, electricity has been encouraged Power user participates in energy-saving and emission-reduction, and realizing reduces the purpose of user's carbon intensity and user's electric energy expense.

Description of the drawings

Fig. 1 is the inventive method flow chart；

Fig. 2 is the result schematic diagram that four nodes in four node power systems are carried out with power flow tracing.

Specific implementation method

Below in conjunction with the accompanying drawings the present invention is described in further detail with specific embodiment.

As shown in figure 1, the present invention provide a kind of consideration carbon tax Economic Dispatch method, the method include with Lower step：

(1) user's carbon tax cost model is set up, specially：

(1.1) the carbon intensity EL of load is determined_j：

A. the carbon intensity EG of every generating set is determined_i；

B. power flow tracing technology is utilized, it is determined that determine the power source of each power load, by electromotor-sharing of load system Matrix number is expressed as A, A_ijRepresent i-th electromotor to j-th burden apportionment coefficient.All electromotors are to j-th load Partition coefficient sum is 1, i.e.,Wherein Ng is electromotor number；

C. the carbon intensity of load is determined：By the carbon intensity of load be set to the electromotor powered of the oriented load The weighted mean of carbon intensity, i.e.,：

By taking four node power systems as an example, the result for carrying out power flow tracing to four nodes is as shown in Figure 2.

The power flow direction of electromotor-load can be expressed as with electromotor-load contribution factor matrix A：

According to the result of Fig. 2, obtain：

Therefore：

EL₁=0.6882 × EG₁+0.2890×EG₂

EL₂=0.3118 × EG₁+0.7110×EG₂

(1.2) the carbon tax cost of user is determined：By the carbon intensity EL of load_jWith loading PL_jProduct is used as the load The carbon emission amount for causing, by all load carbon emission amounts and carbon tax T_jThe sum of products as the total carbon tax cost f of user_C.I.e.：Nl is the number of system internal loading.

(2) economic load dispatching model is set up, specially：

(2.1) object function is determined：With the total carbon tax sum of the total cost of electricity-generating of system and user as object function, i.e., Min f=f_G+f_C, wherein f_GFor the cost of electricity-generating sum of all electromotors.

(2.2) constraints is determined：Power-balance constraint, branch power constraint, node voltage amplitude constraint, electromotor go out Force constraint.

A. power-balance constraint：

Wherein, P_Gi, Q_Gi, P_Di, Q_DiRespectively in node i in the active power of electromotor output, reactive power and node i The active power of load, reactive power.θ_iWith | V_i| the respectively phase angle and amplitude of node i voltage, G_ijAnd B_ijRespectively branch road The equivalent conductance and susceptance of i-j, N_bFor system node number.

B. generator output constraint：

Wherein,P _Gi ,The lower limit and the upper limit of electromotor active power of output respectively in node i,Q _Gi ,Respectively save The lower limit and the upper limit of electromotor output reactive power on point i.

C. branch power constraint：

|S_ij|≤|S_ij|^max

Wherein, | S_ij| for the apparent energy of branch road i-j, | S_ij|^maxFor the upper limit of the apparent energy of branch road i-j.

D. node voltage amplitude constraint：

|V_i|^min≤|V_i|≤|V_i|^max

Wherein, | V_i|^min, | V_i|^maxThe respectively lower limit and the upper limit of node i voltage magnitude.

(3) economic load dispatching model is solved：Economic load dispatching model is solved using prim al- dual interior point m ethod, it is determined that sending out per platform The active and idle plan of exerting oneself of motor.Economic load dispatching model is solved using prim al- dual interior point m ethod, needs to ask object function to becoming The single order of amount is led and is led with second order.Meanwhile, in electromotor-sharing of load coefficient square that step (1) is determined using power flow tracing technology Inverse matrix Z occurs in battle array A^-1.In solution procedure, will be to Z^-1Derivation problem be converted to the derivation problem to original matrix Z：

Wherein, x_pFor the variable in economic load dispatching model.

It is specific as follows：

Above-mentioned economic load dispatching model, can be expressed as a general optimal models：

min f(x)

S.t.g (x)=0

h(x)≤0

Lagrangian is：

Wherein, Z is that slack variable is vectorial, Z_mFor the element in Z, n_iFor the quantity of inequality constraints, λ, μ respectively correspondence Equality constraint and the Lagrange multiplier of inequality constraints, γ is obstruction factor.

According to KKT conditions, when being optimal, it is zero to have Lagrangian to lead the single order of each variable, i.e.,：

KKT conditional expressions are solved with Niu Lafa, optimal solution is obtained.

Claims (5)

1. it is a kind of consider carbon tax Economic Dispatch method, it is characterised in that the method is comprised the following steps：

(1) user's carbon tax cost model is set up, specially：

(1.1) the carbon intensity EL of load is determined_j；

(1.2) the carbon tax cost of user is determined：By the carbon intensity EL of load_jWith loading PL_jProduct causes as the load Carbon emission amount, by all load carbon emission amounts and carbon tax T_jThe sum of products as the total carbon tax cost f of user_C.I.e.：Nl is the number of system internal loading.

(2) economic load dispatching model is set up, specially：

(2.1) object function is determined：With the total carbon tax sum of the total cost of electricity-generating of system and user as object function, i.e. Min f =f_G+f_C, wherein f_GFor the cost of electricity-generating sum of all electromotors.

(2.2) constraints is determined：Power-balance constraint, branch power constraint, node voltage amplitude constraint, generator output are about Beam.

(3) economic load dispatching model is solved：Economic load dispatching model is solved using prim al- dual interior point m ethod, determines every electromotor The active and idle plan of exerting oneself.

2. it is according to claim 1 it is a kind of consider carbon tax Economic Dispatch method, it is characterised in that the step Suddenly (1) is set up in user's carbon tax cost model, determines the carbon intensity EL of load_jRefer to：

A. the carbon intensity EG of every generating set is determined_i；

B. power flow tracing technology is utilized, it is determined that determine the power source of each power load, by electromotor-sharing of load coefficient square Matrix representation is A, A_ijRepresent i-th electromotor to j-th burden apportionment coefficient.All electromotors are to j-th burden apportionment Coefficient sum is 1, i.e.,Wherein Ng is electromotor number；

C. the carbon intensity of load is determined：By the carbon intensity of load be set to the oriented load power electromotor carbon row The weighted mean of intensity is put, i.e.,：

3. it is according to claim 1 it is a kind of consider carbon tax Economic Dispatch method, it is characterised in that the step Suddenly (1) is set up in user's carbon tax cost model, determines the carbon intensity EL of load_j, EL_jIt is depending on the change of electromotor output Amount.

4. it is according to claim 1 it is a kind of consider carbon tax Economic Dispatch method, it is characterised in that the step Suddenly (2) set up economic load dispatching model, and the model is specifically referred to：

1. object function：

Min f=f_G+f_C

2. constraints：

A. power-balance constraint：

$\left\{\begin{array}{c}{P}_{Gi}-P_{Di}-\left|V_i\right|\underset{j=1}{\overset{N_b}{\mathrm{\Σ}}}\left|V_j\right|\left(G_{ij}cos\right({\mathrm{\θ}}_i-{\mathrm{\θ}}_j)+B_{ij}sin({\mathrm{\θ}}_i-{\mathrm{\θ}}_j\left)\right)=0\\ Q_{Gi}-Q_{Di}-\left|V_i\right|\underset{j=1}{\overset{N_b}{\mathrm{\Σ}}}\left|V_j\right|\left(G_{ij}\sin \right({\mathrm{\θ}}_i-{\mathrm{\θ}}_j)-B_{ij}\cos ({\mathrm{\θ}}_i-{\mathrm{\θ}}_j\left)\right)=0\end{array}\right.$

Wherein, P_Gi, Q_Gi, P_Di, Q_DiLoad in the active power of electromotor output, reactive power and node i respectively in node i Active power, reactive power.θ_iWith | V_i| the respectively phase angle and amplitude of node i voltage, G_ijAnd B_ijRespectively branch road i-j's Equivalent conductance and susceptance, N_bFor system node number.

B. generator output constraint：

$\left\{\begin{array}{c}\underset{\‾}{P_{Gi}}\≤P_{Gi}\≤\stackrel{\‾}{P_{Gi}}\\ \underset{\‾}{Q_{Gi}}\≤Q_{Gi}\≤\stackrel{\‾}{Q_{Gi}}\end{array}\right.$

Wherein,P _Gi ,The lower limit and the upper limit of electromotor active power of output respectively in node i,Q _Gi ,Respectively node i The lower limit and the upper limit of upper electromotor output reactive power.

C. branch power constraint：

|S_ij|≤|S_ij|^max

Wherein, | S_ij| for the apparent energy of branch road i-j, | S_ij|^maxFor the upper limit of the apparent energy of branch road i-j.

D. node voltage amplitude constraint：

|V_i|^min≤|V_i|≤|V_i|^max

Wherein, | V_i|^min, | V_i|^maxThe respectively lower limit and the upper limit of node i voltage magnitude.

5. it is according to claim 1 it is a kind of consider carbon tax Economic Dispatch method, it is characterised in that step (3) economic load dispatching model is solved using prim al- dual interior point m ethod, needs to ask that object function is led to the single order of variable and second order is led.Together When, inverse matrix Z occurs in the electromotor that step (1) is determined using power flow tracing technology-sharing of load coefficient matrices A^-1. In solution procedure, will be to Z^-1Derivation problem be converted to the derivation problem to original matrix Z：

$\frac{{\mathrm{dZ}}^{-1}}{{\mathrm{dx}}_p}=-Z^{-1}\frac{dZ}{{\mathrm{dx}}_p}{Z}^{-1}$

Wherein, x_pFor the variable in economic load dispatching model.