CN103972916B - Energy storage device is utilized to stabilize the micro-capacitance sensor operation method of scene power swing - Google Patents

Abstract

Energy storage device is utilized to stabilize the micro-capacitance sensor operation method of scene power swing, belong to intelligent micro-grid technical field, the present invention solves that existing micro-capacitance sensor wind-power electricity generation, photovoltaic generation unit output have undulatory property, randomness and intermittence, and then the problem affecting the stable operation of micro-capacitance sensor.The detailed process of the method for the invention is: determine structural parameters and the operational factor of micro-capacitance sensor according to the system of micro-capacitance sensor；Choose each distributed power source in micro-grid system meritorious output and micro-capacitance sensor is purchased to bulk power grid, the power of sale of electricity as control variable, obtain the operating cost function of micro-capacitance sensor, the object function run by operating cost function as micro-capacitance sensor according to control variable；The mathematical model for stabilizing the energy storage device that scene fluctuates and the constraints of micro-capacitance sensor operation is obtained according to object function；Utilize and improve the micro-capacitance sensor operation method after power swing is stabilized in differential evolution algorithm acquisition.The present invention is in micro-grid system.

Description

Energy storage device is utilized to stabilize the micro-capacitance sensor operation method of scene power swing

Technical field

The invention belongs to intelligent micro-grid technical field.

Background technology

Along with the high speed development of human society, the demand of the energy is strengthened, not to living environment prescription by the mankind simultaneously Disconnected raising, the micro-capacitance sensor containing combined type new forms of energy has obtained people and has more and more paid close attention to.Novel distributed power source can Make full use of the generating advantage of regenerative resource, but novel distributed power source exists the biggest difference with conventional power source, its Being mainly characterized by wind-power electricity generation, the randomness of photovoltaic generation, undulatory property and intermittence makes micro-grid system bear disturbance Ability is relatively weak.In order to make full use of the generating advantage of new distribution type power supply, weaken its power swing shadow to micro-capacitance sensor Ring, safeguard system stability, micro-grid system must comprise synchronous generator unit or the energy storage device of certain capacity.Energy storage fills Putting and be capable of fast charging and discharging, wind is stabilized in the realization that matches with the renewable energy power generation unit such as wind-power electricity generation, photovoltaic generation Optical power fluctuation, the power output of stabilisation systems, strengthen the schedulable performance of renewable energy system.Therefore energy storage dress The reasonable employment put can effectively weaken the impact that the stable operation of micro-capacitance sensor is caused by new distribution type power supply.

At present micro-capacitance sensor is optimized and run existing fruitful research, but according to the actual operating state of micro-capacitance sensor, right The features such as randomness that the wind-power electricity generation that comprises in micro-capacitance sensor, the output of photovoltaic generation unit have, undulatory property are to micro- The impact of power grid operation need to study further and solve.

Summary of the invention

The invention aims to solve existing micro-capacitance sensor wind-power electricity generation, photovoltaic generation unit output has undulatory property, with Machine and intermittence, and then the problem affecting the stable operation of micro-capacitance sensor, it is provided that one utilizes energy storage device to stabilize scene merit The micro-capacitance sensor operation method of rate fluctuation.

The micro-capacitance sensor operation method utilizing energy storage device to stabilize scene power swing of the present invention, the detailed process of the method For:

Step one, system according to micro-capacitance sensor determine structural parameters and the operational factor of micro-capacitance sensor；

Step 2, choose the meritorious output of each distributed power source in micro-grid system and micro-capacitance sensor is purchased to bulk power grid, the merit of sale of electricity Rate, as control variable, obtains the operating cost function of micro-capacitance sensor, using operating cost function as micro-capacitance sensor according to control variable The object function run；

Step 3, the object function obtained according to step 2 obtain the mathematical model of energy storage device for stabilizing scene fluctuation；

Step 4, micro-capacitance sensor run constraints under, utilize improve differential evolution algorithm obtain stabilizes scene power swing After the output of each distributed power source, be the micro-capacitance sensor operation method after stabilizing power swing.

Advantages of the present invention: the micro-capacitance sensor operation method utilizing energy storage device to stabilize scene power swing of the present invention, energy Enough for micro-grid system actual motion time the wind-power electricity generation that comprises, the regenerative resource such as photovoltaic generation have undulatory property, with The impact that micro-grid system is run by machine and intermittent feature.According to wind-powered electricity generation, the real-time output of photovoltaic generation, calculate It is relative to the fluctuation situation of a upper scheduling instance output, if exceeding the maximum fluctuation scope of permission, then energy storage device enters Row discharge and recharge is to stabilize power swing；Energy storage device also needs according to whole micro-grid system supply and demand while stating target in realization Situation and the sale of electricity electricity price situation of purchasing of associated bulk power grid, the reasonable discharge and recharge of energy storage device is so that realizing micro-grid system and gathering around The person of having obtains greatest benefit.

Accompanying drawing explanation

Fig. 1 is the structural representation of micro-capacitance sensor；

Fig. 2 is wind-power electricity generation, photovoltaic generation real-time output power curve figure；

Fig. 3 is to stabilize wind-power electricity generation, the output power curve figure of photovoltaic generation after scene power swing；

Fig. 4 is the energy storage device charge-discharge electric power curve chart that blower fan bus connects；

Fig. 5 is the energy storage device charge-discharge electric power curve chart that photovoltaic generator bus connects.

Detailed description of the invention

Detailed description of the invention one: present embodiment is described below in conjunction with Fig. 1, utilizes energy storage device to stabilize described in present embodiment The micro-capacitance sensor operation method of scene power swing, the detailed process of the method is:

Step one, system according to micro-capacitance sensor determine structural parameters and the operational factor of micro-capacitance sensor；

Step 2, choose the meritorious output of each distributed power source in micro-grid system and micro-capacitance sensor is purchased to bulk power grid, the merit of sale of electricity Rate, as control variable, obtains the operating cost function of micro-capacitance sensor, using operating cost function as micro-capacitance sensor according to control variable The object function run；

Step 3, the object function obtained according to step 2 obtain the mathematical model of energy storage device for stabilizing scene fluctuation；

Step 4, micro-capacitance sensor run constraints under, utilize improve differential evolution algorithm obtain stabilizes scene power swing After the output of each distributed power source, be the micro-capacitance sensor operation method after stabilizing power swing.

In present embodiment, described structural parameters include bus parameter and line parameter circuit value；Described operational factor includes each distributed The service data of power supply, load data and scheduling time inter.

Detailed description of the invention two: embodiment one is described further by present embodiment, and described in step 2, micro-capacitance sensor runs into Originally include that fuel cost, charges for disposing pollutants, operation and maintenance cost and bulk power grid purchase sale of electricity expense, then using operating cost as target Function representation is:

$F=\underset{T=1}{\overset{M}{\mathrm{\Σ}}}[\underset{i=1}{\overset{N}{\mathrm{\Σ}}}(C_{\mathrm{OP}}\left(P_{\mathrm{Gi}}\right)+C_{\mathrm{ES}}\left(P_{\mathrm{Gi}}\right)+C_{\mathrm{OM}}\left(P_{\mathrm{Gi}}\right))+C_b\·P_{\mathrm{bgrid}}-C_s\·P_{\mathrm{sgrid}}]$

Wherein: N represents that number of power sources, i represent i-th power supply, C_OPRepresent the fuel cost of distributed power source i, C_ESTable Show the discharge fee of distributed power source i, C_OMRepresent the operation and maintenance cost of distributed power source i, C_bRepresent bulk power grid power purchase Price, unit is unit/kW h, C_sRepresenting bulk power grid sale of electricity price, unit is kW h, P_GiRepresent power supply in certain period The generated energy of i, unit is kW h, P_bgridRepresenting the electric energy of power purchase in certain period, unit is kW h, P_sgridRepresent The electric energy of sale of electricity in certain period, unit is kW h；M represents period number；T represents a certain period of scheduling.

Detailed description of the invention three: embodiment one is described further by present embodiment, according to object function described in step 3 The energy storage device mathematical model obtained is:

$|P_{\mathrm{py}}\left(t\right)-P_{\mathrm{py}}(t-1)|\≤S\·\mathrm{\λ}$

P_ess(t)=P_py(t)-P_max(t)

Wherein: P_py(t) represent t stabilize after output；P_py(t-1) defeated after the t-1 moment stabilizes of wind-powered electricity generation is represented Go out power；P_maxT () represents the peak power output of t output；P_essT () represents the charge-discharge electric power of energy storage device；S table

Show installed capacity；λ represents the maximum rate of change of energy storage device output；

Work as P_ess(t) > 0 time, energy storage device discharge, work as P_essT () < when 0, energy storage device charges；

Energy storage device meets at the capacity of t:

C_ess(t)=C_ess(t-1)(1-δ)-P_ess(t)·η·△t

Wherein: C_ess(t)、C_ess(t-1) representing the capability value of t and t-1 moment energy storage device respectively, unit is kW h；δ is The self-discharge current rate of energy storage device；η is the efficiency for charge-discharge of energy storage device；△ t represents the changing value in t and t-1 moment；

After energy storage device discharge and recharge, capacity is at { C_essmin, C_essmaxBetween }, after charging, capacity is more than C_essmaxTime, energy storage fills Putting stopping charging, capacity and the charge power of energy storage device are as follows:

$\left\{\begin{array}{c}{P}_{\mathrm{ess}}=-\frac{C_{\mathrm{ess}\max }-C_{\mathrm{ess}}(t-1)(1-\mathrm{\&delta;})}{\mathrm{\&Delta;t}\&CenterDot;\mathrm{\&eta;}}\\ C_{\mathrm{ess}}\left(t\right)=C_{\mathrm{ess}\max }\end{array}\right.$

After energy storage device electric discharge, capacity is less than C_essminTime, energy storage device stops electric discharge, the capacity of energy storage device and discharge power As follows:

$\left\{\begin{array}{c}{P}_{\mathrm{ess}}=-\frac{C_{\mathrm{ess}\min }-C_{\mathrm{ess}}(t-1)(1-\mathrm{\&delta;})}{\mathrm{\&Delta;t}\&CenterDot;\mathrm{\&eta;}}\\ C_{\mathrm{ess}}\left(t\right)=C_{\mathrm{ess}\min }\end{array}\right.$

Energy storage device is in the case of meeting above-mentioned condition, and the condition of charge-discharge electric power is

$\left\{\begin{array}{c}{P}_{c,\min }\&le;P_{c,\mathrm{ess}}\left(t\right)\&le;P_{c,\max }\\ P_{f,\min }\&le;P_{f,\mathrm{ess}}\left(t\right)\&le;P_{f,\max }\end{array}\right.$

Wherein: P_c,essT () represents the energy storage device charge power in t, P_c,minAnd P_c,maxRepresent charge power respectively Lower limit and the upper limit；P_f,essT () represents the energy storage device discharge power in t, P_f,minAnd P_f,maxRepresent discharge power respectively Lower limit and the upper limit.

In present embodiment, the foundation of energy storage device discharge and recharge is: first, and the active power value exported when wind-powered electricity generation and photovoltaic is big When the maximum fluctuation value that it allows, energy storage device charges, until energy storage device is charged to its maximum capacity, device stops Charging, the principle output that remaining active power is not wasted according to the energy；Second, when the active power that wind-powered electricity generation and photovoltaic export When value is less than its maximum fluctuation value allowed, energy storage device discharges, until energy storage device discharges into its minimum capacity value, next Scheduling instance energy storage device does not discharges.

Detailed description of the invention four: embodiment one is described further by present embodiment, micro-capacitance sensor described in step 4 runs Constraints includes power flow equation constraint, inequality constraints and purchases sale of electricity constraint；

Power flow equation retrains, and is equality constraint, is expressed as:

$\left\{\begin{array}{c}{P}_{\mathrm{Hi}}-P_{\mathrm{Di}}-V_i\underset{j=1}{\overset{n}{\mathrm{\&Sigma;}}}{V}_j(G_{\mathrm{ij}}\cos {\mathrm{\&theta;}}_{\mathrm{ij}}+B_{\mathrm{ij}}\sin {\mathrm{\&theta;}}_{\mathrm{ij}})=0\\ Q_{\mathrm{Hi}}-Q_{\mathrm{Di}}-V_i\underset{j=1}{\overset{n}{\mathrm{\&Sigma;}}}{V}_j(G_{\mathrm{ij}}\sin {\mathrm{\&theta;}}_{\mathrm{ij}}-B_{\mathrm{ij}}\cos {\mathrm{\&theta;}}_{\mathrm{ij}})=0\end{array}\right.$

Wherein: P_HiRepresent the active power of distributed power source i；Q_HiRepresent the reactive power of distributed power source i；P_DiRepresent The load active power of distributed power source i；Q_DiRepresent the reactive load power of distributed power source i；N represents node total number； J represents the connected node of i；θi_jRepresent that what represents the voltage phase angle between i and j；V_jRepresent the voltage magnitude of node j； Gi_jAnd Bi_jAll represent the element in bus admittance matrix；

Inequality constraints includes the constraint of the units limits of distributed power source, node voltage amplitude and capacity of trunk constraint, is expressed as:

$\left\{\begin{array}{c}{P}_{\mathrm{Ki}}^{\min }\&le;P_{\mathrm{Ki}}\&le;P_{\mathrm{Ki}}^{\max }\\ Q_{\mathrm{Ki}}^{\min }\&le;Q_{\mathrm{Ki}}\&le;Q_{\mathrm{Ki}}^{\max }\\ V_{\mathrm{Ki}}^{\min }\&le;V_i\&le;V_{\mathrm{Ki}}^{\max }\\ S_{\mathrm{ij}}\&le;S_{\mathrm{ij}}^{\max }\end{array}\right.$

Wherein: P_KiRepresent the meritorious output of distributed power source i；Q_KiRepresent the idle output of distributed power source i；V_iRepresent The voltage magnitude of distributed power source i；S_ijRepresent the apparent energy of circuit；Superscript max is the upper limit of represented variable Value；Superscript min is the lower limit of represented variable；

Purchase sale of electricity constraint, be expressed as:

$\left\{\begin{array}{c}{P}_{b,\min }\&le;P_b\&le;P_{b,\max }\\ P_{c,\min }\&le;P_c\&le;P_{c,\max }\end{array}\right.$

Wherein: P_bRepresent power purchase, P_cRepresent sale of electricity；The max of subscript is the higher limit of represented variable；Subscript Min is the lower limit of represented variable.

For the micro-grid system structure chart of Fig. 1, use result that method of the present invention obtains as it is shown on figure 3, with figure 2 compare, wind-powered electricity generation, photovoltaic output nearly smooth, Fig. 4 and Fig. 5 sets forth wind-power electricity generation and photovoltaic generation list The charge-discharge electric power of the energy storage device that unit's bus is connect.This shows: the present invention can effectively weaken scene power swing On the basis of micro-grid system stable operation, it is achieved the optimization of micro-grid system runs.

Claims (1)

1. utilizing energy storage device to stabilize the micro-capacitance sensor operation method of scene power swing, the detailed process of the method is:

Step one, system according to micro-capacitance sensor determine structural parameters and the operational factor of micro-capacitance sensor；

Step 2, choose the meritorious output of each distributed power source in micro-grid system and micro-capacitance sensor is purchased to bulk power grid, the merit of sale of electricity Rate, as control variable, obtains the operating cost function of micro-capacitance sensor, using operating cost function as micro-capacitance sensor according to control variable The object function run；

Step 3, the object function obtained according to step 2 obtain the mathematical model of energy storage device for stabilizing scene fluctuation；

Step 4, micro-capacitance sensor run constraints under, utilize improve differential evolution algorithm obtain stabilizes scene power swing After the output of each distributed power source, be the micro-capacitance sensor operation method after stabilizing power swing；

It is characterized in that: micro-capacitance sensor operating cost described in step 2 include fuel cost, charges for disposing pollutants, operation and maintenance cost and Bulk power grid purchases sale of electricity expense, then operating cost be expressed as object function:

$F=\underset{T=1}{\overset{M}{\&Sigma;}}\&lsqb;\underset{i=1}{\overset{N}{\&Sigma;}}\left(C_{OP}\right(P_{Gi})+C_{ES}(P_{Gi})+C_{OM}(P_{Gi}\left)\right)+C_b\&CenterDot;P_{bgrid}-C_s\&CenterDot;P_{sgrid}\&rsqb;$

Wherein: N represents that number of power sources, i represent i-th power supply, C_OPRepresent the fuel cost of distributed power source i, C_ESTable Show the discharge fee of distributed power source i, C_OMRepresent the operation and maintenance cost of distributed power source i, C_bRepresent bulk power grid power purchase valency Lattice, unit is unit/kW h, C_sRepresenting bulk power grid sale of electricity price, unit is unit/kW h, P_GiRepresent power supply i in certain period Generated energy, unit is kW h, P_bgridRepresenting the electric energy of power purchase in certain period, unit is kW h, P_sgridWhen representing certain section The electric energy of interior sale of electricity, unit is kW h；M represents period number；T represents a certain period of scheduling；

The energy storage device mathematical model obtained according to object function described in step 3 is:

|P_py(t)-P_py(t-1)|≤S·λ

P_ess(t)=P_py(t)-P_max(t)

Wherein: P_py(t) represent t stabilize after output；P_py(t-1) wind-powered electricity generation output after the t-1 moment stabilizes is represented Power；P_maxT () represents the peak power output of t output；P_essT () represents the charge-discharge electric power of energy storage device；S represents Installed capacity；λ represents the maximum rate of change of energy storage device output；

Work as P_ess(t) > 0 time, energy storage device discharge, work as P_essT () < when 0, energy storage device charges；

Energy storage device meets at the capacity of t:

C_ess(t)=C_ess(t-1)(1-δ)-P_ess(t)·η·△t

Wherein: C_ess(t)、C_ess(t-1) representing the capability value of t and t-1 moment energy storage device respectively, unit is kW h；δ is The self-discharge current rate of energy storage device；η is the efficiency for charge-discharge of energy storage device；△ t represents the changing value in t and t-1 moment；

After energy storage device discharge and recharge, capacity is at { C_essmin, C_essmaxBetween }, after charging, capacity is more than C_essmaxTime, energy storage device Stopping charging, capacity and the charge power of energy storage device are as follows:

$\left\{\begin{array}{c}{P}_{ess}=-\frac{C_{essmax}-C_{ess}(t-1)(1-\mathrm{\&delta;})}{\mathrm{\&Delta;}t\&CenterDot;\mathrm{\&eta;}}\\ C_{ess}\left(t\right)=C_{essmax}\end{array}\right.$

After energy storage device electric discharge, capacity is less than C_essminTime, energy storage device stops electric discharge, and the capacity of energy storage device and discharge power are such as Under:

$\left\{\begin{array}{c}{P}_{ess}=-\frac{C_{essmin}-C_{ess}(t-1)(1-\mathrm{\&delta;})}{\mathrm{\&Delta;}t\&CenterDot;\mathrm{\&eta;}}\\ C_{ess}\left(t\right)=C_{essmin}\end{array}\right.$

Energy storage device is in the case of meeting above-mentioned condition, and the condition of charge-discharge electric power is

$\left\{\begin{array}{c}{P}_{c,min}\&le;P_{c,ess}\left(t\right)\&le;P_{c,max}\\ P_{f,min}\&le;P_{f,ess}\left(t\right)\&le;P_{f,max}\end{array}\right.$

Wherein: P_c,essT () represents the energy storage device charge power in t, P_c,minAnd P_c,maxRepresent respectively under charge power Limit and the upper limit；P_f,essT () represents the energy storage device discharge power in t, P_f,minAnd P_f,maxRepresent respectively under discharge power Limit and the upper limit.