CN103414201A - Regulation and control method of electric bus power battery cluster participating in sea island micro-grid operation - Google Patents

Abstract

The invention discloses a regulation and control method of an electric bus power battery cluster participating in sea island micro-grid operation. The method comprises the following steps: predicting loads and an electricity generation power curve of new energy resources, sampling data in an optimized time frame, calculating the surplus capacity of a bus-mounted power battery, determining the battery management mode, constructing an electric bus cost model, constructing a diesel generator cost model, building a system operation optimized objective function, concluding optimized constraint conditions, processing the optimized and updated portion, and conducting global optimization solution on a regulation and control model.

Description

Electric bus electrokinetic cell cluster participates in the regulate and control method of island microgrid operation

Technical field

The present invention relates to a kind of electric bus electrokinetic cell cluster and as energy-storage travelling wave tube, participate in the regulate and control operation method of island microgrid, take into account dynamic power balance and the economical operation optimization of island micro-grid system.

Background technology

Due to away from the grid-connected difficulty in continent, the island microgrid has self salient feature, and the generation of electricity by new energy permeability is high, system operation cost is high is its outstanding feature.It is to realize its dynamic power balance, the key factor of safeguards system frequency quality that energy storage device or the diesel power plant participation regulate and control operation of enough capacity are provided.The general special-purpose energy storage device (comprising flywheel energy storage, super capacitor, batteries etc.) be equipped with of microgrid is expensive and maintenance cost is very high, has greatly improved investment, the operating cost of island microgrid.Fast development along with electric automobile (EV) and electric automobile access network (V2G) technology, can consider to introduce electric bus as island environmental protection public transport, and the replacing electrokinetic cell cluster of it is vehicle-mounted and supporting electrical changing station is as the regulate and control operation of energy-storage travelling wave tube participation island microgrid.On the one hand, can greatly reduce the cost of investment of the special-purpose energy-storage system of island microgrid; On the other hand, by the V2G technology, electric bus battery cluster is realized peak load shifting for both can be used as controllable burden, improve overall generating efficiency and the economic benefit of electrical network, also can guarantee under the normal prerequisite of Vehicle Driving Cycle function, according to system requirements and each electric bus battery cluster state (SOC), by discharging and recharging the scheduling controlling of conversion, the dynamic equilibrium of energy in the participation system.

Current, V2G, as a kind of comparatively novel electrical network control technique, relates to its research that participates in island microgrid regulate and control operation less, also has no island powerup issue, V2G technology and power are exerted oneself and optimized the Patents invention of combining closely.For the exert oneself main approaches optimized of microgrid power, concentrate on and have or not V2G to participate in the lower peak regulation Contrast on effect of regulation and control and V2G is single as regulating and controlling micro-source, the optimization of exerting oneself of the power of namely only considering the microgrid distributed power source of its electric discharge.The former has illustrated that to a great extent V2G participates in the validity of microgrid regulation and control, but on economic performance, does not verify in conjunction with real actual conditions that V2G participates in feasibility and the validity of regulation and control; The latter distributes the source of declining while exerting oneself in considering microgrid, only consider the EV electric discharge, it is not considered, this does not conform to the actual conditions, in addition, these class methods are the optimization of single period, because on macroscopic view and the overall situation, not considering the economy that V2G power is exerted oneself, a rear period can only be realized suboptimum because of the impact that is subjected to the last period, and this probably misses the distribution of exerting oneself of best power.The present invention participates in the regulate and control operation of island microgrid at V2G, consideration, using electric bus electrokinetic cell cluster namely as micro-source, also as load, is guaranteeing under the reliable rideability of automobile and the effect of V2G peak load shifting, realize the global power optimization of exerting oneself, can make up the shortcoming that above-mentioned single period optimizes.

Summary of the invention

The present invention will overcome the problems such as microgrid new forms of energy fluctuation large and system capacity dynamic equilibrium in existing island is with high costs, a kind of economic optimization regulate and control method that electric bus electrokinetic cell cluster is participated in to island microgrid operation of proposition.

The present invention for achieving the above object, has proposed electric bus electrokinetic cell cluster and has participated in island microgrid regulate and control operation method, and its concrete block diagram as shown in Figure 1, comprises the steps:

1) prediction load and generation of electricity by new energy power curve: according to known parameters and model, dope daily load curve in the microgrid of island and the day generated output curve of all kinds of new forms of energy distributed power generation devices (DG);

2) optimize the period data sampling: determine the minimum period Δ t of optimization, and according to this each curve of step 1) gained is sampled, obtain the load prediction value P in each i ∈ [1, N] period _LDi, each j class new forms of energy DG(solar energy, wind energy etc.) generated output predicted value P _{DG (j) i}Wherein, N is hop count while determining the optimization of dividing according to the Δ t set in a day; Suppose that in the interior system of Δ t, load power, exerting oneself of each generator unit all keep constant;

3) the vehicle mounted dynamic battery residual capacity is calculated: according to the electric bus practical operation situation and the electrokinetic cell configuring condition thereof that participate in island microgrid V2G service, by calculating the total kilometrage that travels each vehicle day, estimate the residual capacity SOC of k car vehicle mounted dynamic battery _BAT(k);

4) battery management mode decision: accompanying drawing 2 is depicted as considers that bus adopts by batch dispersion period of sequentially putting into operation a replacing battery mode, can determine that according to this each vehicle changes the number of batteries that battery time and day part can participate in the V2G regulation and control, and upgrade and constraints is formulated foundation is provided for system battery cluster active volume;

5) build electric automobile cost model: C _EV=C _STC+ C _SU+ C _RE, i.e. the Financial cost (comprising income) of electric bus participation V2G comprises 3 parts---energy storage cost C _STC, V2G participates in subsidy C _SU, the V2G peak valley discharges and recharges benefit C _RE

6) build diesel engine generator cost model: C _DSG=C _FU+ C _ENV+ C _DE, i.e. the Financial cost of diesel engine generator generating comprises 3 parts---fuel consume expense C _FU, Environmental costs C _ENV, the unit equipment depreciable cost;

7) set up the running Optimization target function: consider that the island microgrid may be in lonely net and network two kinds of operational modes, integrating step 5) and step 6), can set up the unitized economic optimization regulation-control model that electrokinetic cell cluster V2G participates in its regulate and control operation, target function is suc as formula shown in (1):

$\left\{\begin{array}{c}\min f(P_{\mathrm{EV}},P_{\mathrm{DSG}},P_{\mathrm{CH}})=\min \{f_1\left(P_{\mathrm{EV}}\right)+f_2\left(P_{\mathrm{DSG}}\right)+c{f}_3\left(P_{\mathrm{CH}}\right)+C_{\mathrm{ST}}\}\\ f_1\left(P_{\mathrm{EV}}\right)=-\underset{i=1}{\overset{N}{\mathrm{\Σ}}}f(P_{\mathrm{EVi}}\×\mathrm{\Δt})P_{\mathrm{EVi}}\×\mathrm{\Δt}\\ f_2\left(P_{\mathrm{DSG}}\right)=a\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{P}_{\mathrm{DSGi}}\×\mathrm{\Δt}\\ f_3\left(P_{\mathrm{CH}}\right)=b\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{P}_{\mathrm{CHi}}\end{array}\right.---\left(1\right)$

Wherein: f ₁(x), f ₂(x), f ₃(x) be respectively V2G electrokinetic cell cluster, diesel engine generator, may have the regulation and control cost variable part of external electrical network; C _STFor participating in the fixed cost part of regulation and control; F (x) is island microgrid time-of-use tariffs function; A is the cost coefficient that diesel engine generator participates in regulation and control; B is the exchange electricity price (power purchase valency>sell electricity price) of island microgrid and outer net; C is that island microgrid operational mode is selected coefficient (lonely net c=0, networking c=1); P _EVi, P _DSGi, P _CHiThe battery of electric vehicle cluster of corresponding i period discharges and recharges power, diesel generating set power output and outer net exchange power respectively;

8) conclude and optimize constraints: each the definite battery loading and unloading period capacity-constrained of charge and discharge constraint, active volume constraint, power constraint, step 4) that considers the battery cluster, and the power constraint of diesel engine generator and the exchange power constraint that may have external electrical network, obtain the constraints of system optimization suc as formula shown in (2):

Wherein: SOC _minWith SOC _maxMinimum, the maximum state-of-charge of difference battery; P _N(DSG) be diesel generating set rated power; P _CHmaxThe power limit can bear for the outer net interconnector; E _BATFor single Battery pack total capacity; M _iBy the i period correspondence participate in the regulation and control number of batteries; i _K1For t constantly is installed _K1The place period;

9) optimize to upgrade section processes: in period usually, the battery period is installed, unloads the battery period and participate in regulation and control battery cluster capacity respectively by formula (3), formula (4) and formula (5) renewal;

SOC(i+1)·E _BAT·N _i+1=SOC(i)·E _BAT·N _i+P _EVi·Δt (3)

$\mathrm{SOC}(i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}+1}=\mathrm{SOC}\left(i_{k1}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}-E_{\mathrm{BAT}}---\left(4\right)$

$\mathrm{SOC}(i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}+1}=\mathrm{SOC}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}+\mathrm{SO}{C}_{\mathrm{BAT}}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}---\left(5\right)$

10) global optimization of regulation-control model solves: by the definite target function of step 7), and integrating step 8) constraints of giving, adopt particle group optimizing (PSO) algorithm with weight to solve.As shown in Figure 3, different from general single period optimization method, this algorithm optimization process is based on all the period of time optimum ideals, take and realize that overall economic optimum is target, can obtain day part electric bus electrokinetic cell cluster, the diesel engine generator under the microgrid dynamic power balance of island and the performance number P of the external electrical network that may exist _EVi, P _DSGiAnd P _CHi.

Beneficial effect of the present invention is, electric bus electrokinetic cell cluster can be participated in to the regulate and control operation of island microgrid, not only greatly reduce the cost of investment of former special-purpose energy-storage system, and by the V2G technology, can by the electrokinetic cell cluster, discharge and recharge the Real time optimal dispatch control of conversion, realize simultaneously dynamic power balance and the economical operation optimization of island micro-grid system.

The accompanying drawing explanation

Fig. 1 is the entire block diagram that V2G participates in island microgrid operation control strategy.

Fig. 2 is for participating in the number of batteries time distribution map of island microgrid regulation and control.

Fig. 3 is the V2G power global optimization key diagram of exerting oneself.

Fig. 4 optimizes gained island microgrid each several part power profile under lonely net fine day sight in embodiment.

Fig. 5 optimizes gained island microgrid each several part power profile under networking rainy day two kinds of sights in embodiment.

Embodiment

Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited to this.The economic optimization regulation and control flow chart of electric bus electrokinetic cell cluster participation island microgrid operation in embodiment as shown in Figure 1, comprises the following steps:

1) prediction load and generation of electricity by new energy power curve: according to known parameters and model, dope daily load curve in the microgrid of island and the day generated output curve of all kinds of new forms of energy distributed power generation devices (DG);

2) optimize the period data sampling: determine the minimum period Δ t of optimization, and according to this each curve of step 1) gained is sampled, obtain the load prediction value P in each i ∈ [1, N] period _LDi, each j class new forms of energy DG(solar energy, wind energy etc.) generated output predicted value P _{DG (j) i}.Wherein, N is hop count while determining the optimization of dividing according to the Δ t set in a day; Suppose that in the interior system of Δ t, load power, exerting oneself of each generator unit all keep constant;

3) the vehicle mounted dynamic battery residual capacity is calculated: according to the electric bus practical operation situation and the electrokinetic cell configuring condition thereof that participate in island microgrid V2G service, by calculating the total kilometrage that travels each vehicle day, estimate the residual capacity SOC of k car vehicle mounted dynamic battery _BAT(k);

4) battery management mode decision: accompanying drawing 2 is depicted as considers that bus adopts by batch dispersion period of sequentially putting into operation a replacing battery mode, can determine that according to this each vehicle changes the number of batteries that battery time and day part can participate in the V2G regulation and control, and upgrade and constraints is formulated foundation is provided for system battery cluster active volume;

5) build electric automobile cost model: C _EV=C _STC+ C _SU+ C _RE, i.e. the Financial cost (comprising income) of electric bus participation V2G comprises 3 parts---energy storage cost C _STC, V2G participates in subsidy C _SU, the V2G peak valley discharges and recharges benefit C _RE

6) build diesel engine generator cost model: C _DSG=C _FU+ C _ENV+ C _DE, i.e. the Financial cost of diesel engine generator generating comprises 3 parts---fuel consume expense C _FU, Environmental costs C _ENV, the unit equipment depreciable cost;

7) set up the running Optimization target function: consider that the island microgrid may be in lonely net and network two kinds of operational modes, integrating step 5) and step 6), can set up the unitized economic optimization regulation-control model that electrokinetic cell cluster V2G participates in its regulate and control operation, target function is suc as formula shown in (6):

$\left\{\begin{array}{c}\min f(P_{\mathrm{EV}},P_{\mathrm{DSG}},P_{\mathrm{CH}})=\min \{f_1\left(P_{\mathrm{EV}}\right)+f_2\left(P_{\mathrm{DSG}}\right)+c{f}_3\left(P_{\mathrm{CH}}\right)+C_{\mathrm{ST}}\}\\ f_1\left(P_{\mathrm{EV}}\right)=-\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}f(P_{\mathrm{EVi}}\&times;\mathrm{\&Delta;t})P_{\mathrm{EVi}}\&times;\mathrm{\&Delta;t}\\ f_2\left(P_{\mathrm{DSG}}\right)=a\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{P}_{\mathrm{DSGi}}\&times;\mathrm{\&Delta;t}\\ f_3\left(P_{\mathrm{CH}}\right)=b\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{P}_{\mathrm{CHi}}\end{array}\right.---\left(6\right)$

Wherein: f ₁(x), f ₂(x), f ₃(x) be respectively V2G electrokinetic cell cluster, diesel engine generator, may have the regulation and control cost variable part of external electrical network; C _STFor participating in the fixed cost part of regulation and control; F (x) is island microgrid time-of-use tariffs function; A is the cost coefficient that diesel engine generator participates in regulation and control; B is the exchange electricity price (power purchase valency>sell electricity price) of island microgrid and outer net; C is that island microgrid operational mode is selected coefficient (lonely net c=0, networking c=1); P _EVi, P _DSGi, P _CHiThe battery of electric vehicle cluster of corresponding i period discharges and recharges power, diesel generating set power output and outer net exchange power respectively;

8) conclude and optimize constraints: each the definite battery loading and unloading period capacity-constrained of charge and discharge constraint, active volume constraint, power constraint, step 4) that considers the battery cluster, and the power constraint of diesel engine generator and the exchange power constraint that may have external electrical network, obtain the constraints of system optimization suc as formula shown in (7):

Wherein: SOC _minWith SOC _maxMinimum, the maximum state-of-charge of difference battery; P _N(DSG) be diesel generating set rated power; P _CHmaxThe power limit can bear for the outer net interconnector.E _BATFor single Battery pack total capacity; M _iBy the i period correspondence participate in the regulation and control number of batteries; i _K1For t constantly is installed _K1The place period;

9) optimize to upgrade section processes: in period usually, the battery period is installed, unloads the battery period and participate in regulation and control battery cluster capacity respectively by formula (8), formula (9) and formula (10) renewal;

SOC(i+1)·E _BAT·N _i+1=SOC(i)·E _BAT·N _i+P _EVi·Δt (8)

$\mathrm{SOC}(i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}+1}=\mathrm{SOC}\left(i_{k1}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}1}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}-E_{\mathrm{BAT}}---\left(9\right)$

$\mathrm{SOC}(i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}+1}=\mathrm{SOC}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="201310301549X100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">k</figure-callout>}2}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}+\mathrm{SO}{C}_{\mathrm{BAT}}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}---\left(10\right)$

10) global optimization of regulation-control model solves: by the definite target function of step 7), and integrating step 8) constraints of giving, adopt particle group optimizing (PSO) algorithm with weight to solve.As shown in Figure 3, different from general single period optimization method, this algorithm optimization process is based on all the period of time optimum ideals, take and realize that overall economic optimum is target, can obtain day part electric bus electrokinetic cell cluster, the diesel engine generator under the microgrid dynamic power balance of island and the optimum power value P of the external electrical network that may exist _EVi, P _DSGiAnd P _CHi.

In the present embodiment, adopt two kinds of island microgrid operation sights, the i.e. lonely net fine day of S1(patterns) and S2(networking rainy day pattern).Set up island micro-grid system as shown in Figure 4, and in conjunction with its internal load, renewable DG configuration and the configuration of energy balance key element, as shown in table 1.

Table 1 example island microgrid related data

By step 1) and 2) can obtain day part load and each DG generating data, and 10 electric bus that come into operation, design comes and goes circuit and vehicle operating timetable, by step 4), calculate and install and unload vehicle mounted dynamic battery residual capacity constantly, integrating step 5) with step 6) gained DSG cost model and EV cost model, set up economic optimization target function (change part and standing part), under determined each constraints of step 8), employing solves with the particle swarm optimization algorithm of weight, obtain the day part electric bus electrokinetic cell cluster under the microgrid dynamic power balance of island, the optimum power value P of diesel engine generator and the external electrical network that may exist _EVi, P _DSGiand P _CHi, as shown in Figure 5.

As mentioned above; just can realize preferably the present invention, above-described embodiment is only exemplary embodiments of the present invention, not is used for limiting practical range of the present invention; be that all equalizations of doing according to content of the present invention change and modify, all by the claims in the present invention scope required for protection, contained.

Claims (1)

1. electric bus electrokinetic cell cluster participates in island microgrid regulate and control operation method, comprises the steps:

1) prediction load and generation of electricity by new energy power curve: according to known parameters and model, dope daily load curve in the microgrid of island and the day generated output curve of all kinds of new forms of energy distributed power generation devices (DG);

2) optimize the period data sampling: determine the minimum period Δ t of optimization, and according to this each curve of step 1) gained is sampled, obtain the load prediction value P in each i ∈ [1, N] period _LDi, each j class new forms of energy DG(solar energy, wind energy etc.) generated output predicted value P _{DG (j) i}Wherein, N is hop count while determining the optimization of dividing according to the Δ t set in a day; Suppose that in the interior system of Δ t, load power, exerting oneself of each generator unit all keep constant;

3) the vehicle mounted dynamic battery residual capacity is calculated: according to the electric bus practical operation situation and the electrokinetic cell configuring condition thereof that participate in island microgrid V2G service, by calculating the total kilometrage that travels each vehicle day, estimate the residual capacity SOC of k car vehicle mounted dynamic battery _BAT(k);

4) battery management mode decision: accompanying drawing 2 is depicted as considers that bus adopts by batch dispersion period of sequentially putting into operation a replacing battery mode, can determine that according to this each vehicle changes the number of batteries that battery time and day part can participate in the V2G regulation and control, and upgrade and constraints is formulated foundation is provided for system battery cluster active volume;

5) build electric automobile cost model: C _EV=C _STC+ C _SU+ C _RE, i.e. the Financial cost (comprising income) of electric bus participation V2G comprises 3 parts---energy storage cost C _STC, V2G participates in subsidy C _SU, the V2G peak valley discharges and recharges benefit C _RE

6) build diesel engine generator cost model: C _DSG=C _FU+ C _ENV+ C _DE, i.e. the Financial cost of diesel engine generator generating comprises 3 parts---fuel consume expense C _FU, Environmental costs C _ENV, the unit equipment depreciable cost;

7) set up the running Optimization target function: consider that the island microgrid may be in lonely net and network two kinds of operational modes, integrating step 5) and step 6), can set up the unitized economic optimization regulation-control model that electrokinetic cell cluster V2G participates in its regulate and control operation, target function is suc as formula shown in (1):

$\left\{\begin{array}{c}\min f(P_{\mathrm{EV}},P_{\mathrm{DSG}},P_{\mathrm{CH}})=\min \{f_1\left(P_{\mathrm{EV}}\right)+f_2\left(P_{\mathrm{DSG}}\right)+c{f}_3\left(P_{\mathrm{CH}}\right)+C_{\mathrm{ST}}\}\\ f_1\left(P_{\mathrm{EV}}\right)=-\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}f(P_{\mathrm{EVi}}\&times;\mathrm{\&Delta;t})P_{\mathrm{EVi}}\&times;\mathrm{\&Delta;t}\\ f_2\left(P_{\mathrm{DSG}}\right)=a\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{P}_{\mathrm{DSGi}}\&times;\mathrm{\&Delta;t}\\ f_3\left(P_{\mathrm{CH}}\right)=b\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{P}_{\mathrm{CHi}}\end{array}\right.---\left(1\right)$

Wherein: f ₁(x), f ₂(x), f ₃(x) be respectively V2G electrokinetic cell cluster, diesel engine generator, may have the regulation and control cost variable part of external electrical network; F (x) is island microgrid time-of-use tariffs function; C _STFor participating in the fixed cost part of regulation and control; A is the cost coefficient that diesel engine generator participates in regulation and control; B is the exchange electricity price (power purchase valency>sell electricity price) of island microgrid and outer net; C is that island microgrid operational mode is selected coefficient (lonely net c=0, networking c=1); P _EVi, P _DSGi, P _CHiThe battery of electric vehicle cluster of corresponding i period discharges and recharges power, diesel generating set power output and outer net exchange power respectively;

8) conclude and optimize constraints: each the definite battery loading and unloading period capacity-constrained of charge and discharge constraint, active volume constraint, power constraint, step 4) that considers the battery cluster, and the power constraint of diesel engine generator and the exchange power constraint that may have external electrical network, obtain the constraints of system optimization suc as formula shown in (2):

Wherein: SOC _minWith SOC _maxMinimum, the maximum state-of-charge of difference battery; P _N(DSG) be diesel generating set rated power; P _CHmaxThe power limit can bear for the outer net interconnector; E _BATFor single Battery pack total capacity; M _iBy the i period correspondence participate in the regulation and control number of batteries; i _K1For t constantly is installed _K1The place period;

9) optimize to upgrade section processes: in period usually, the battery period is installed, unloads the battery period and participate in regulation and control battery cluster capacity respectively by formula (3), formula (4) and formula (5) renewal;

SOC(i+1)·E _BAT·N _i+1=SOC(i)·E _BAT·N _i+P _EVi·Δt (3)

$\mathrm{SOC}(i_{k1}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{k1}+1}=\mathrm{SOC}\left(i_{k1}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{k1}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}-E_{\mathrm{BAT}}---\left(4\right)$

$\mathrm{SOC}(i_{k2}+1)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{k2}+1}=\mathrm{SOC}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}\&CenterDot;M_{i_{k2}}+P_{\mathrm{EVi}}\&CenterDot;\mathrm{\&Delta;t}+\mathrm{SO}{C}_{\mathrm{BAT}}\left(i_{k2}\right)\&CenterDot;E_{\mathrm{BAT}}---\left(5\right)$

10) global optimization of regulation-control model solves: by the definite target function of step 7), and integrating step 8) constraints of giving, adopt particle group optimizing (PSO) algorithm with weight to solve.As shown in Figure 3, different from general single period optimization method, this algorithm optimization process is based on all the period of time optimum ideals, take and realize that overall economic optimum is target, can obtain day part electric bus electrokinetic cell cluster, the diesel engine generator under the microgrid dynamic power balance of island and the performance number P of the external electrical network that may exist _EVi, P _DSGiAnd P _CHi.

Images