CN107872071B - Power generation method and device for supplying power to power grid - Google Patents

Abstract

The embodiment of the invention discloses a power generation method and a power generation device for supplying power to a power grid, wherein the method comprises the following steps: determining a frequency modulation service adjusting range and sending the frequency modulation service adjusting range to a power grid dispatching system, generating an AGC dispatching instruction by the power grid dispatching system according to a plan curve and the frequency modulation service adjusting range, and sending the plan curve and the AGC dispatching instruction to a coordination controller; the coordination controller receives an AGC dispatching instruction and sends the AGC dispatching instruction to the energy storage system controller; the coordination controller receives the plan curve and sends the plan curve to the generating set controller, the generating set controller controls and detects the output power of the generating set and sends the output power to the energy storage system controller, and the energy storage system controller controls the output power of the energy storage system according to the difference value of the target output force value and the current output power. Because the power grid dispatching system can generate the AGC dispatching instruction according to the frequency modulation service adjusting range, the energy storage system cannot be overcharged or overdischarged frequently, and further the overall operation cost is lower and the operation income is larger.

Description

Power generation method and device for supplying power to power grid

Technical Field

The invention relates to the technical field of electric power, in particular to a power generation method and a power generation device for supplying power to a power grid.

Background

The power grid system comprises a power grid dispatching system and a power generation system, wherein the power generation system is used for supplying power to a power grid, and the power grid dispatching system is used for issuing a dispatching instruction to dispatch the power generation system to generate power. Specifically, the power generation system includes a power generator set, a power generator set controller for controlling the output of the power generator set, an energy storage system controller for controlling the output of the energy storage system, and a coordination controller for coordinating the power generator set controller and the energy storage system controller, where the coordination controller is used to assist the communication among the power grid dispatching system, the power generator set controller, and the energy storage system controller, for example, to forward dispatching commands issued by the power grid dispatching system to the power generator set controller and the energy storage system controller.

The power generation system not only needs to meet the requirement of the power consumption and the electric quantity of a load user, but also needs to maintain the stability of the real-time frequency and the flow of a connecting line of a power grid so as to ensure the stability and the reliability of the operation of the whole power grid. In the process of grid-connected operation of the generator set, the generator set needs to provide both electric quantity service and AGC (automatic Generation control) frequency modulation service. The electric quantity service refers to providing grid-connected output according to a plan curve, wherein the plan curve is a relation curve between the grid-connected output and time, which is formulated according to the required electric quantity of a power grid; and the AGC frequency modulation service refers to tracking a rapid change instruction signal under the scheduling of a power grid scheduling system, and adjusting the grid-connected output in real time so as to ensure the stability of the power grid frequency and the power flow of a connecting line.

The generator set is limited by the characteristics of the generator set, the output adjusting speed is low, the adjusting precision is poor, the quality of AGC frequency modulation service is poor, and the income cannot be guaranteed. In addition, when the generator set provides AGC frequency modulation service, the output of the generator set is required to be adjusted rapidly and repeatedly, so that adverse consequences such as fluctuation of operating parameters of the generator set, reduction of operating efficiency, aggravation of abrasion and aging of executing mechanisms such as a generator valve and the like can be caused, and the operating cost of the generator set is far higher than that of a stable output mode when only electric quantity service is provided.

Different from a generator set, the energy storage system is considered to be very suitable for quick adjustment application of AGC frequency modulation service and the like due to the high adjustment speed and high adjustment precision. The energy storage system and the generator set jointly operate, respond to a power grid AGC dispatching instruction and participate in power grid operation. Under the combined operation mode of the energy storage system and the generator set, the energy storage system can be used as a quick unit to compensate the real-time deviation between the output of the generator set and a power grid dispatching instruction, and mainly provides an AGC frequency modulation service function. The generator set is used as a slow unit to provide energy support for long-term operation of a power grid and mainly provide an electric quantity service function. The operation mode of the division and cooperation can exert respective advantages of the energy storage system and the thermal power generating unit.

However, the energy storage system has a limited amount of energy that can be stored, and when it is in a 100% fully charged state or a 0% fully discharged state, the energy storage system cannot provide further charging or discharging capability. The operation life of the energy storage system is influenced by the load intensity, the charging and discharging depth and the operation interval, and frequent overcharge or overdischarge can greatly reduce the operation life of the energy storage system and increase the operation cost. Therefore, how to minimize the overall operation cost of the power generation system and maximize the operation benefit while ensuring that the power generation system provides stable power service and AGC frequency modulation service is a problem which needs to be solved urgently.

Disclosure of Invention

The embodiment of the invention discloses a power generation method and a power generation device for supplying power to a power grid, so that the overall operation cost is lower and the operation benefit is larger while a power generation system provides stable electric quantity service and AGC frequency modulation service. The technical scheme is as follows:

in a first aspect, an embodiment of the present invention provides a power generation method for supplying power to a power grid, which is applied to a coordination controller, and the method includes:

determining the frequency modulation service regulation range;

sending the frequency modulation service adjustment range to a power grid dispatching system so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve obtained in advance and the frequency modulation service adjusting range, and sends the plan curve and the AGC dispatching instruction to the coordination controller, wherein the plan curve carries a first target output value, and the AGC dispatching instruction carries a second target output value;

receiving the AGC dispatching instruction and sending the AGC dispatching instruction to an energy storage system controller;

receiving the planned curve and sending the planned curve to a genset controller such that: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

Optionally, the step of determining the tuning range of the fm service includes:

determining a current charging state value of the energy storage system, wherein the current charging state value is a ratio of current residual energy to rated energy capacity of the energy storage system;

and determining the operation mode of the energy storage system according to the current charging state value, and determining the frequency modulation service regulation range according to the operation mode.

Optionally, before the step of determining the current state of charge value of the energy storage system, the method further includes:

and setting the operation mode of the energy storage system according to a preset initial mode setting mode at the initial operation time of the energy storage system.

Optionally, the step of setting the operation mode of the energy storage system according to a preset initial mode setting manner includes:

when the initial charging state value of the energy storage system is not higher than the operation lower limit, setting the operation mode of the energy storage system as a pure charging mode;

when the initial charging state value of the energy storage system is not lower than the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode;

when the initial charging state value of the energy storage system is lower than the operation upper limit and higher than the operation lower limit, setting the operation mode of the energy storage system to be a pure charging mode or a pure discharging mode;

the initial charging state value is a ratio of residual energy of the energy storage system at an initial operating time to a rated energy capacity, the upper operating limit is a maximum charging state value of the energy storage system charged at a rated power, the lower operating limit is a minimum charging state value of the energy storage system discharged at the rated power, an adjustable output range of the energy storage system corresponding to the pure charging mode is [ -P, 0], an adjustable output range of the energy storage system corresponding to the pure discharging mode is [0, P ], and P is the rated power of the energy storage system.

Optionally, the step of determining the operation mode of the energy storage system according to the current state of charge value, and determining the frequency modulation service adjustment range according to the operation mode includes:

when the current charging state value is not higher than the lower operation limit, setting the operation mode of the energy storage system as the pure charging mode, and setting the frequency modulation service adjustment range as the adjustable output range of the energy storage system corresponding to the pure charging mode;

when the current charging state value is not lower than the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode, and setting the frequency modulation service adjustment range to be an adjustable output range of the energy storage system corresponding to the pure discharging mode;

and when the current charging state value is lower than the upper operation limit and higher than the lower operation limit, keeping the operation mode of the energy storage system unchanged, and setting the frequency modulation service adjustment range as the adjustable output range of the energy storage system corresponding to the operation mode.

Optionally, the method further includes:

when the operation mode of the energy storage system is detected to be a pure charging mode, judging Whether it is less than (upper operating limit-current state of charge value) E;

if so, keeping the operation mode of the energy storage system as a pure charging mode;

if not, switching the operation mode of the energy storage system to a pure discharge mode;

when the operation mode of the energy storage system is detected to be a pure discharge mode, judging

Whether the current state of charge value is less than (current state of charge value-lower operating limit) E;

if so, keeping the operation mode of the energy storage system as a pure discharge mode;

if not, switching the operation mode of the energy storage system to a pure charging mode;

and E is the rated energy capacity of the energy storage system.

Optionally, the step of controlling the generator set output power by the generator set controller according to the first target output value carried by the plan curve specifically includes:

and the generating set controller controls the generating set to output power according to the first target output value carried by the plan curve.

Optionally, the step of determining the tuning range of the fm service specifically includes:

and determining the frequency modulation service regulation range to be [ -P, P ], wherein P is the rated power of the energy storage system.

Optionally, the step of the genset controller controlling the genset output power according to the first target output value carried by the plan curve includes:

receiving a deviation compensation quantity sent by the coordination controller or the energy storage system controller, wherein the deviation compensation quantity represents energy loss of the energy storage system in the operation process;

and controlling the generator set to output the sum of the force value and the deviation compensation quantity according to the first target carried by the plan curve.

Optionally, the obtaining manner of the offset compensation amount includes:

when the deviation compensation amount is sent by the energy storage system controller, the manner of obtaining the deviation compensation amount by the energy storage system controller includes:

the energy storage system controller determines a current charging state value and a target charging state value of the energy storage system, and calculates the deviation compensation quantity according to the current charging state value and the target charging state value of the energy storage system;

when the deviation compensation amount is sent by the coordination controller, the manner for the coordination controller to obtain the deviation compensation amount includes:

the coordination controller receives a current charging state value and a target charging state value of the energy storage system, and calculates the deviation compensation amount according to the current charging state value and the target charging state value of the energy storage system, and the current charging state value and the target charging state value of the energy storage system are determined and sent by the energy storage system controller;

or receiving the deviation compensation quantity sent by the energy storage system, wherein the deviation compensation quantity is obtained by the energy storage system controller according to the current charging state value and the target charging state value of the energy storage system through calculation;

the target state of charge value is an average value of an upper operating limit and a lower operating limit, the upper operating limit is a maximum state of charge value of the energy storage system charged at a rated power, and the lower operating limit is a minimum state of charge value of the energy storage system discharged at the rated power.

Optionally, the second target output value carried by the AGC scheduling instruction is within [ (the first target output value + the fm service adjustment range lower limit), (the first target output value + the fm service adjustment range upper limit) ].

In a second aspect, an embodiment of the present invention further provides a power generation apparatus for supplying power to a power grid, where the apparatus is applied to a coordination controller, and the apparatus includes:

the frequency modulation service adjusting range determining module is used for determining the frequency modulation service adjusting range;

a frequency modulation service adjustment range sending module, configured to send the frequency modulation service adjustment range to a power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve obtained in advance and the frequency modulation service adjusting range, and sends the plan curve and the AGC dispatching instruction to the coordination controller, wherein the plan curve carries a first target output value, and the AGC dispatching instruction carries a second target output value;

the AGC dispatching instruction receiving module is used for receiving the AGC dispatching instruction and sending the AGC dispatching instruction to the energy storage system controller;

a planned curve receiving module for receiving the planned curve and sending the planned curve to a generator set controller so that: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

In the scheme, the coordination controller firstly determines the frequency modulation service regulation range and sends the frequency modulation service regulation range to the power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve and a frequency modulation service regulation range which are obtained in advance, sends the plan curve and the AGC dispatching instruction to the coordination controller, receives the AGC dispatching instruction, sends the AGC dispatching instruction to the energy storage system controller, receives the plan curve, and sends the plan curve to the generator set controller, so that: the generator set controller controls the output power of the generator set according to a first target output value carried by the plan curve, detects the current output power of the generator set in real time, and sends the current output power of the generator set to the energy storage system controller, so that: and the energy storage system controller controls the output power of the energy storage system according to the second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set. Because the power grid dispatching system can generate AGC dispatching instructions according to the frequency modulation service regulation range, the energy storage system cannot be overcharged or overdischarged frequently, and meanwhile, the generator set controller controls the output power of the generator set according to a plan curve obtained in advance, the overall operation cost is lower, and the operation benefit is larger.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a flow chart of a power generation method for supplying power to a power grid according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a power generation device for supplying power to a power grid according to an embodiment of the present invention.

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 only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to ensure that a power generation system provides stable electric quantity service and AGC frequency modulation service, and simultaneously ensure that the overall operation cost of the power generation system is the lowest and the operation benefit is the greatest, the embodiment of the invention provides a power generation method and a power generation device for supplying power to a power grid.

First, it should be noted that, in order to describe the power generation method and apparatus for supplying power to a power grid according to the embodiments of the present invention, in this document, when an energy storage system feeds out electric energy to the power grid, that is, when the energy storage system discharges, it is defined that output power of the energy storage system is positive; when the energy storage system absorbs electric energy from the power grid, namely when the energy storage system is charged, the output power of the energy storage system is defined to be negative. When the generator set feeds electric energy out of the power grid, namely the generator set discharges, the output power of the generator set is defined to be positive.

First, a first power generation method for supplying power to a power grid according to an embodiment of the present invention will be described below.

As shown in fig. 1, a power generation method for supplying power to a power grid is applied to a coordination controller, and includes the following steps:

s101, determining a frequency modulation service adjusting range;

in practical applications, the coordination controller may determine the tuning range of the fm service in two ways:

the first method for determining the tuning range of the fm service may specifically include:

determining a current state of charge value of the energy storage system;

and determining the operation mode of the energy storage system according to the current charging state value, and determining the frequency modulation service regulation range according to the operation mode.

And the current charging state value is the ratio of the current residual energy of the energy storage system to the rated energy capacity. For example, if the current remaining energy of the energy storage system is 75MW · h (megawatt hour), the rated energy capacity of the energy storage system is 100MW · h, and the current state of charge value of the energy storage system is 75/100 ═ 75%.

After the energy storage system controller determines the current charging state value of the energy storage system, the operating mode of the energy storage system can be set according to the current charging state value, so that the operating mode of the energy storage system can be set according to the actual charging and discharging state of the energy storage system, the quick and repeated output adjustment requirement is converted into the adjustment requirement with long duration and few conversion times in one direction, and meanwhile, the service life of the energy storage system is prevented from being influenced by the danger of over-charging or over-discharging of the energy storage system.

It should be noted that, at the initial time when the energy storage system is put into operation, that is, the initial time of operation, the operation mode of the energy storage system may be set according to the initial state of charge value of the energy storage system at the initial time of operation, and the specific setting manner may include:

when the initial charging state value of the energy storage system is not higher than (lower than) the operation lower limit, setting the operation mode of the energy storage system to be a pure charging mode;

when the initial charging state value of the energy storage system is not lower than (higher than) the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode;

and when the initial charging state value of the energy storage system is lower than the operation upper limit and higher than the operation lower limit, setting the operation mode of the energy storage system to be a pure charging mode or a pure discharging mode.

The upper operating limit is a maximum state of charge value at which the energy storage system is charged at rated power. It can be understood that, as a device for providing electric energy, in practical applications, the maximum state of charge value of the energy storage system is generally not 100%, so that the energy storage system is prevented from being overcharged and the service life of the energy storage system is reduced, so that the energy storage system has a maximum state of charge value that is charged at a rated power, that is, the upper limit of operation is an inherent property of the energy storage system, and the upper limits of operation of different types of energy storage systems are different, for example, may be 80%, 90%, and so on.

Accordingly, the lower operating limit is a minimum state of charge value at which the energy storage system is discharged at rated power. The minimum state of charge value for its discharge will generally not be 0%, the lower operating limit is also an inherent property of the energy storage system, and the lower operating limits for different types of energy storage systems are also different, e.g., may be 15%, 20%, etc.

Further, the initial state of charge value is a ratio of a remaining energy of the energy storage system at the initial time of operation to a rated energy capacity, for example, the remaining energy of the energy storage system at the initial time of operation is 55MW · h, the rated energy capacity of the energy storage system is 100MW · h, and then the current state of charge value of the energy storage system is 55/100 ═ 55%.

When the energy storage system controller judges that the initial charging state value of the energy storage system is not higher than the operation lower limit, for example, the initial charging state value of the energy storage system is 10%, and the operation lower limit is 20%, at this time, it is described that the residual energy of the energy storage system at the operation initial moment is less, and the amount of electric energy allowed to be charged is more, that is, the chargeable capacity is very good, so that the operation mode of the energy storage system can be set to be a simple charging mode, that is, the energy storage system is set to absorb electric energy from the power grid simply, and the energy storage system is prevented from performing quick and repeated output adjustment. The adjustable output range of the energy storage system corresponding to the pure charging mode is [ -P, 0], that is, the charging power of the energy storage system may be a value between [0, P ], where P is the rated power of the energy storage system.

When the current initial charging state value of the energy storage system is judged to be not lower than the operation upper limit, for example, the initial charging state value of the energy storage system is 90%, and the operation upper limit is 85%, at this time, it is described that the residual energy of the energy storage system at the operation initial moment is more, the electric quantity allowed to be discharged is more, that is, the dischargeable capacity is good, then the operation mode of the energy storage system can be set to be a pure discharge mode, that is, the energy storage system is set to be only fed out the electric quantity to the power grid, and the energy storage system is prevented from performing quick and repeated output adjustment. The adjustable output range of the energy storage system corresponding to the pure discharge mode is [0, P ], that is, the discharge power of the energy storage system may be a value between [0, P ].

When the initial charge state value of the energy storage system is judged to be lower than the operation upper limit and higher than the operation lower limit, for example, the initial charge state value of the energy storage system is 50%, the operation upper limit is 85%, and the operation lower limit is 20%, at this time, it is described that the residual energy of the energy storage system at the operation initial moment is moderate, the difference between the electric quantities allowed to discharge or discharge is not very large, that is, the energy storage system has certain dischargeable capacity and chargeable capacity at this time, so that the operation mode of the energy storage system can be set to be one of a simple charge mode and a simple discharge mode.

After the energy storage system is put into operation according to the set operation mode, the energy storage system controller can detect the current charging state value of the energy storage system in real time, and then carry out switching control on the operation mode of the energy storage system according to the current charging state value, and determine the frequency modulation service adjusting range according to the operation mode of the energy storage system, and the specific mode can include:

when the current charging state value is not higher than the lower operation limit, setting the operation mode of the energy storage system as the pure charging mode, and setting the frequency modulation service adjustment range as the adjustable output range of the energy storage system corresponding to the pure charging mode;

when the current charging state value is not lower than the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode, and setting the frequency modulation service adjustment range to be an adjustable output range of the energy storage system corresponding to the pure discharging mode;

and when the current charging state value is lower than the upper operation limit and higher than the lower operation limit, keeping the operation mode of the energy storage system unchanged, and setting the frequency modulation service adjustment range as the adjustable output range of the energy storage system corresponding to the operation mode.

That is, when the current charging state value of the energy storage system reaches the operation lower limit, that is, is not higher than the operation lower limit, the operation mode of the energy storage system is switched to a pure charging mode; and when the current charging state value of the energy storage system reaches the upper operation limit, converting the operation mode of the energy storage system into a pure discharging mode. When the current charging state of the energy storage system is greater than the operation lower limit and less than the operation upper limit (namely, between the operation upper limit and the operation lower limit), the operation mode of the energy storage system is kept unchanged, namely, the operation mode of the energy storage system is kept to be the original set operation mode. Once the current charging state value of the energy storage system reaches the upper running limit or the lower running limit, the running mode needs to be converted, so that the danger of overcharge or overdischarge of the energy storage system can be avoided, the energy storage system is enabled to run in the optimal charging and discharging state, and the service life of the energy storage system is further prolonged.

Specifically, when the operation mode of the energy storage system is the simple charging mode, the coordination controller may set the frequency modulation service adjustment range to [ -P, 0], and when the operation mode of the energy storage system is the simple discharging mode, the frequency modulation service adjustment range may be set to [0, P ]. Therefore, the frequency modulation service adjusting range is within the adjustable output range of the energy storage system, and the danger of overcharge or overdischarge of the energy storage system is avoided.

The second tuning range determination method may specifically be:

and determining the frequency modulation service regulation range to be [ -P, P ], wherein P is the rated power of the energy storage system. That is, the frequency modulation service is only provided by the energy storage system at this time.

S102, sending the frequency modulation service regulation range to a power grid dispatching system so as to: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve obtained in advance and the frequency modulation service regulation range, and sends the plan curve and the AGC dispatching instruction to the coordination controller;

and the plan curve carries a first target force output value, and the AGC dispatching instruction carries a second target force output value. After determining the frequency modulation service adjustment range, the coordination controller may send the frequency modulation service adjustment range to a power grid dispatching system, and after receiving the frequency modulation service adjustment range, the power grid dispatching system may generate an AGC dispatching instruction according to a plan curve obtained in advance and the frequency modulation service adjustment range, so that a second target output value carried by the AGC dispatching instruction is within [ (the first target output value + the lower limit of the frequency modulation service adjustment range), (the first target output value + the upper limit of the frequency modulation service adjustment range) ]. Therefore, the requirements of AGC dispatching instructions can be met in the running process of the generator set and the energy storage system, and meanwhile, the problem of frequent over-charging or over-discharging of the energy storage system can not occur.

There are generally two ways to obtain the planning curve. Specifically, under a market mechanism, a plan curve in the current time period can be obtained through a day-ahead electricity market or a real-time electricity market bidding mode. Under the planning mechanism, a planning curve can be formulated and issued by the power grid dispatching system according to the prediction result of the power grid load in the day before.

And after the power grid dispatching system determines the AGC dispatching instruction, the planning curve and the AGC dispatching instruction are sent to the coordination controller, so that the coordination controller can conveniently carry out further work.

S103, receiving the AGC scheduling instruction and sending the AGC scheduling instruction to an energy storage system controller;

after receiving the AGC dispatching instruction sent by the power grid dispatching system, the coordination controller may forward the AGC dispatching instruction to the energy storage system controller.

S104, receiving the plan curve and sending the plan curve to a generator set controller so as to: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

The coordination controller may forward the schedule curve to the genset controller while forwarding the AGC dispatch instructions to the energy storage system controller. After receiving the plan curve, the generator set controller can control the output power of the generator set according to the first target output value carried by the plan curve, detect the current output power of the generator set in real time and send the current output power of the generator set to the energy storage system controller.

Specifically, when the frequency modulation service range is [ -P, 0] or [0, P ], since the operation mode of the energy storage system is switched between the pure charging mode and the pure discharging mode, there is no need to compensate the energy loss of the energy storage system during the operation process by the generator set, so that the generator set controller can control the generator set to output power according to the first target output value carried by the plan curve, that is, control the generator set to output power according to the first target output value carried by the plan curve without deviation.

When the frequency modulation service range is [ -P, P ], since only the energy storage system provides the frequency modulation service at this time, it is necessary to compensate and control the energy loss of the energy storage system during the operation process by the generator set to ensure that the energy storage system does not risk the overcharge or the overdischarge, and therefore the controlling of the output power of the generator set by the generator set controller according to the schedule curve may include:

receiving deviation compensation quantity sent by a coordination controller or an energy storage system controller;

and controlling the generator set to output the sum of the force value and the deviation compensation value according to the first target carried by the plan curve.

The deviation compensation amount represents energy loss of the energy storage system during operation, and the deviation compensation amount is obtained in two manners. Specifically, when the deviation compensation amount is sent by the energy storage system controller, the manner of obtaining the deviation compensation amount by the energy storage system controller includes:

the energy storage system controller determines a current charging state value and a target charging state value of the energy storage system, and calculates a deviation compensation quantity according to the current charging state value and the target charging state value of the energy storage system.

Wherein the target state of charge value is an average of the upper operating limit and the lower operating limit. For example, if the upper operating limit is 80% and the lower operating limit is 20%, the target soc value is 50%. After the energy storage system controller determines the current state of charge value and the target state of charge value, the deviation compensation amount can be calculated by the PI controller, and of course, the deviation compensation amount can also be obtained by other existing methods. It should be noted that, the calculation of the offset compensation amount by the PI controller is a common calculation method in the art, and a person skilled in the art can operate the method according to actual situations, and is not specifically described here.

When the offset compensation amount is sent by the coordination controller, the manner in which the coordination controller obtains the offset compensation amount may include:

the coordination controller receives the current charging state value and the target charging state value of the energy storage system, and calculates the deviation compensation amount according to the current charging state value and the target charging state value of the energy storage system.

The current charging state value and the target charging state value of the energy storage system are determined by the energy storage system controller and sent to the coordination controller, and the coordination controller determines the deviation compensation amount after receiving the current charging state value and the target charging state value. It should be noted that the calculation method of the offset compensation amount is the same as the above calculation method, and the calculation may also be performed by using a PI controller, which is not described herein again.

Another way for the coordination controller to obtain the offset compensation amount is: and receiving the deviation compensation quantity sent by the energy storage system. The offset compensation amount is calculated by the energy storage system controller according to the current charging state value and the target charging state value of the energy storage system, and the specific calculation method is the same as the calculation method in the method for obtaining the offset compensation amount by the energy storage system controller, and is not described herein again.

Furthermore, the generator set controller can detect the current output power of the generator set in real time while controlling the output power of the generator set according to the deviation compensation quantity, and sends the current output power of the generator set to the energy storage system controller. And the energy storage system controller can calculate the difference value of the second target output value carried by the received AGC dispatching instruction sent by the coordination controller and the current output power of the generator set according to the received second target output value and the current output power of the generator set, and control the output power of the energy storage system to compensate the difference value.

If the difference is positive, it indicates that the current output power of the generator set cannot meet the power supply requirement of the power grid at the moment, the energy storage system controller controls the energy storage system to discharge so as to supplement the deficiency of the current output power of the generator set; if the difference value is negative, the current output power of the generator set exceeds the power supply requirement of the power grid at the moment, and the energy storage system controller controls the energy storage system to charge so as to supplement the energy of the energy storage system and ensure the coincidence with the power supply requirement of the power grid. For example, if the second target output value carried by the AGC scheduling command is 265MW and the current output power of the generator set is 260MW, the energy storage system controller controls the energy storage system to discharge with an output power of 5 MW.

Therefore, in the scheme, the coordination controller firstly determines the frequency modulation service adjustment range and sends the frequency modulation service adjustment range to the power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve and a frequency modulation service regulation range which are obtained in advance, sends the plan curve and the AGC dispatching instruction to the coordination controller, receives the AGC dispatching instruction, sends the AGC dispatching instruction to the energy storage system controller, receives the plan curve, and sends the plan curve to the generator set controller, so that: the generator set controller controls the output power of the generator set according to a first target output value carried by the plan curve, detects the current output power of the generator set in real time, and sends the current output power of the generator set to the energy storage system controller, so that: and the energy storage system controller controls the output power of the energy storage system according to the second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set. Because the power grid dispatching system can generate AGC dispatching instructions according to the frequency modulation service regulation range, the energy storage system cannot be overcharged or overdischarged frequently, and meanwhile, the generator set controller controls the output power of the generator set according to a plan curve obtained in advance, the overall operation cost is lower, and the operation benefit is larger.

It should be noted that the manner of detecting the current charging state value of the energy storage system in real time by the energy storage system controller and then performing switching control on the operation mode of the energy storage system according to the current charging state value may further include:

when the operation mode of the energy storage system is detected to be a pure charging mode, judging Whether it is less than (upper operating limit-current state of charge value) E;

if so, keeping the operation mode of the energy storage system as a pure charging mode;

if not, switching the operation mode of the energy storage system to a pure discharge mode;

when the operation mode of the energy storage system is detected to be a pure discharge mode, judging

Whether the current state of charge value is less than (current state of charge value-lower operating limit) E;

if so, keeping the operation mode of the energy storage system as a pure discharge mode;

if not, switching the operation mode of the energy storage system to a pure charging mode;

and E is the rated energy capacity of the energy storage system.

When the operation mode of the energy storage system is detected to be a pure charging mode, the output power of the energy storage system is between 0 and the rated charging power P, and then the average charging power of the energy storage system can be determined to be P/2. The accumulated charging capacity of the energy storage system in the delta T time interval is the charging capacity

When it is judged that

When T is smaller than (the upper limit of operation-the current charging state value) and E, the current charging state value of the energy storage system after the time length of delta T does not exceed the upper limit of operation, namely the energy storage system does not have the risk of overcharging, and then the operation mode of the energy storage system can be kept to be the pure charging mode.

When it is judged that When the current charging state value is not less than (the upper operation limit-the current charging state value) or E, it is indicated that the current charging state value of the energy storage system after the time duration of Δ T is likely to exceed the upper operation limit, that is, the energy storage system may have a risk of overcharging, and then the operation mode of the energy storage system may be switched to a pure discharging mode, so as to ensure that the energy storage system does not have the risk of overcharging.

Similarly, when the operation mode of the energy storage system is detected to be the pure discharge mode, the output power of the energy storage system is between-P and the rated charging power 0, and then the average discharge power of the energy storage system can be determined to be P/2. The accumulated discharge capacity of the energy storage system in the delta T time interval is the discharge capacity

When it is judged that When the current charging state value is less than (the current charging state value-the operation lower limit) or E, the current charging state value of the energy storage system after the time length of delta T is not less than the operation lower limit, namely the energy storage system does not have the risk of overdischarge, and then the operation mode of the energy storage system can be kept to be the pure discharge mode.

When it is judged that When the current charging state value is not less than (current charging state value-operation lower limit) · E, it is very likely that the current charging state value of the energy storage system after the time length of delta T will be lower than the operation lower limit, that is, the current charging state value is not less than the operation lower limit, that is, the current charging state value is less than the operation lowerThe energy storage system may have a risk of overdischarge, and then the operation mode of the energy storage system can be switched to a pure charging mode, so that the risk of overdischarge of the energy storage system is avoided.

Corresponding to the method embodiment, the embodiment of the invention also provides a power generation device for supplying power to the power grid. The following describes a power generation device for supplying power to a power grid according to an embodiment of the present invention.

As shown in fig. 2, a power generation device for supplying power to a power grid is applied to a coordination controller, and the device comprises:

a frequency modulation service adjustment range determining module 210, configured to determine a frequency modulation service adjustment range;

a fm service tuning range sending module 220, configured to send the fm service tuning range to a power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve obtained in advance and the frequency modulation service regulation range, and sends the plan curve and the AGC dispatching instruction to the coordination controller;

and the plan curve carries a first target force output value, and the AGC dispatching instruction carries a second target force output value.

An AGC dispatching instruction receiving module 230, configured to receive the AGC dispatching instruction, and send the AGC dispatching instruction to an energy storage system controller;

a planned curve receiving module 240, configured to receive the planned curve and send the planned curve to the generator set controller, so that: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

Therefore, in the scheme, the coordination controller firstly determines the frequency modulation service adjustment range and sends the frequency modulation service adjustment range to the power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve and a frequency modulation service regulation range which are obtained in advance, sends the plan curve and the AGC dispatching instruction to the coordination controller, receives the AGC dispatching instruction, sends the AGC dispatching instruction to the energy storage system controller, receives the plan curve, and sends the plan curve to the generator set controller, so that: the generator set controller controls the output power of the generator set according to a first target output value carried by the plan curve, detects the current output power of the generator set in real time, and sends the current output power of the generator set to the energy storage system controller, so that: and the energy storage system controller controls the output power of the energy storage system according to the second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set. Because the power grid dispatching system can generate AGC dispatching instructions according to the frequency modulation service regulation range, the energy storage system cannot be overcharged or overdischarged frequently, and meanwhile, the generator set controller controls the output power of the generator set according to a plan curve obtained in advance, the overall operation cost is lower, and the operation benefit is larger.

In an embodiment of the present invention, the fm service tuning range determining module 210 may include:

a current state-of-charge value determination unit (not shown in the figure) for determining a current state-of-charge value of the energy storage system;

and the current charging state value is the ratio of the current residual energy of the energy storage system to the rated energy capacity.

And an fm service adjustment range determining unit (not shown in the figure) configured to determine an operation mode of the energy storage system according to the current charging state value, and determine an fm service adjustment range according to the operation mode.

In one embodiment of the present invention, the apparatus may further include:

an initial operation mode setting module (not shown in the figure) configured to set an operation mode of the energy storage system according to a preset initial mode setting manner at an initial operation time of the energy storage system before determining the current charge state value of the energy storage system.

In an embodiment of the present invention, the initial operation mode setting module may include:

a first initial setting unit (not shown in the figure), configured to set an operation mode of the energy storage system to a pure charging mode when an initial charging state value of the energy storage system is not higher than an operation lower limit;

a second initial setting unit (not shown in the figure), configured to set an operation mode of the energy storage system to a pure discharge mode when an initial charge state value of the energy storage system is not lower than an upper operation limit;

a third initial setting unit (not shown in the figure), configured to set an operation mode of the energy storage system to be a pure charging mode or a pure discharging mode when an initial charging state value of the energy storage system is lower than the upper operation limit and higher than the lower operation limit;

the initial charging state value is a ratio of residual energy of the energy storage system at an initial operating time to a rated energy capacity, the upper operating limit is a maximum charging state value of the energy storage system charged at a rated power, the lower operating limit is a minimum charging state value of the energy storage system discharged at the rated power, an adjustable output range of the energy storage system corresponding to the pure charging mode is [ -P, 0], an adjustable output range of the energy storage system corresponding to the pure discharging mode is [0, P ], and P is the rated power of the energy storage system.

In an embodiment of the present invention, the fm service tuning range determining module 210 may include:

a first setting unit (not shown in the figure), configured to set the operating mode of the energy storage system to the pure charging mode and set the frequency modulation service adjustment range to an adjustable output range of the energy storage system corresponding to the pure charging mode when the current charging state value is not higher than the lower operating limit;

a second setting unit (not shown in the figure), configured to set the operating mode of the energy storage system to be a pure discharge mode when the current charge state value is not lower than an upper operating limit, and set the frequency modulation service adjustment range to be an adjustable output range of the energy storage system corresponding to the pure discharge mode;

and a third setting unit (not shown in the figure), configured to, when the current charge state value is lower than the upper operation limit and higher than the lower operation limit, keep the operation mode of the energy storage system unchanged, and set the frequency modulation service adjustment range as an adjustable output range of the energy storage system corresponding to the operation mode.

In one embodiment of the present invention, the apparatus may further include:

a first determining module (not shown in the figures) for determining whether the operation mode of the energy storage system is a pure charging mode

Whether it is less than (upper operating limit-current state of charge value) E;

a first execution module (not shown in the figure) for executing the steps

When the current charging state value is less than (the upper operation limit-the current charging state value) E, keeping the operation mode of the energy storage system as a pure charging mode;

a second execution module (not shown in the figure) for executing the steps

When the current charging state value is not less than (the upper operation limit-the current charging state value) E, switching the operation mode of the energy storage system into a pure discharging mode;

a second determining module (not shown in the figures) for determining whether the operation mode of the energy storage system is a pure discharging mode

Whether the current state of charge value is less than (current state of charge value-lower operating limit) E;

a third execution module (not shown in the figure) for executing the steps When the current charge state value is less than (the current charge state value-the operation lower limit) E, keeping the operation mode of the energy storage system as a pure discharge mode;

a fourth execution module (not shown in the figure), for executing the steps When the current charging state value is not less than (the current charging state value-the running lower limit) E, switching the running mode of the energy storage system into a pure charging mode;

and E is the rated energy capacity of the energy storage system.

In an embodiment of the present invention, the plan curve receiving module 240 may include:

a genset process control unit (not shown) for receiving the planned curve and sending the planned curve to a genset controller such that: and the generating set controller controls the generating set to output power according to the first target output value carried by the plan curve.

In an embodiment of the present invention, the fm service tuning range determining module 210 may be specifically configured to:

and determining the frequency modulation service regulation range to be [ -P, P ], wherein P is the rated power of the energy storage system.

In an embodiment of the present invention, the plan curve receiving module 240 may include:

an offset compensation amount acquisition unit (not shown in the figure) for receiving the planned curve and sending the planned curve to the generator set controller so that: the generating set controller receives the deviation compensation quantity sent by the coordination controller or the energy storage system controller;

wherein the offset compensation amount represents an energy loss of the energy storage system during operation;

and the power output unit (not shown in the figure) is used for controlling the generator set to output power according to the sum of the first target force output value and the deviation compensation value carried by the plan curve.

In one embodiment of the present invention, when the offset compensation amount is sent by the energy storage system controller, the offset compensation amount obtaining unit may include:

a first deviation compensation amount obtaining subunit (not shown in the figure), configured to determine a current charging state value and a target charging state value of the energy storage system by the energy storage system controller, and calculate the deviation compensation amount according to the current charging state value and the target charging state value of the energy storage system;

when the offset compensation amount is transmitted by the coordination controller, the offset compensation amount acquisition unit may include:

a second deviation compensation quantity obtaining subunit (not shown in the figure), configured to receive the current charging state value and the target charging state value of the energy storage system, and calculate the deviation compensation quantity according to the current charging state value and the target charging state value of the energy storage system, where the current charging state value and the target charging state value of the energy storage system are determined and sent by the energy storage system controller;

a third deviation compensation quantity obtaining subunit (not shown in the figure), configured to receive the deviation compensation quantity sent by the energy storage system, where the deviation compensation quantity is calculated by the energy storage system controller according to a current charging state value and a target charging state value of the energy storage system;

the target state of charge value is an average value of an upper operating limit and a lower operating limit, the upper operating limit is a maximum state of charge value of the energy storage system charged at a rated power, and the lower operating limit is a minimum state of charge value of the energy storage system discharged at the rated power.

In an embodiment of the present invention, the target output value carried by the AGC scheduling instruction is within [ (the first target output value + the fm service adjustment range lower limit), (the first target output value + the fm service adjustment range upper limit) ].

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, as for the apparatus embodiment, since it is substantially similar to the method embodiment, the description is relatively simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

Those skilled in the art will appreciate that all or part of the steps in the above method embodiments may be implemented by a program to instruct relevant hardware to perform the steps, and the program may be stored in a computer-readable storage medium, which is referred to herein as a storage medium, such as: ROM/RAM, magnetic disk, optical disk, etc.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims (11)

1. A method of generating power for a power grid, for use in a coordinating controller, the method comprising:

determining a frequency modulation service power regulation range;

sending the frequency modulation service power regulation range to a power grid dispatching system so as to: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve and the frequency modulation service power regulation range which are obtained in advance, and sends the plan curve and the AGC dispatching instruction to the coordination controller, wherein the plan curve carries a first target output value, the AGC dispatching instruction carries a second target output value, and the second target output value is in the range of [ (the first target output value + the frequency modulation service power regulation range lower limit), (the first target output value + the frequency modulation service power regulation range upper limit) ];

receiving the AGC dispatching instruction and sending the AGC dispatching instruction to an energy storage system controller;

receiving the planned curve and sending the planned curve to a genset controller such that: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

2. The method of claim 1, wherein the step of determining a frequency modulation service power adjustment range comprises:

determining a current charging state value of the energy storage system, wherein the current charging state value is a ratio of current residual energy to rated energy capacity of the energy storage system;

and determining the operation mode of the energy storage system according to the current charging state value, and determining the frequency modulation service power regulation range according to the operation mode.

3. The method of claim 2, wherein the step of determining the current state of charge value of the energy storage system is preceded by the method further comprising:

and setting the operation mode of the energy storage system according to a preset initial mode setting mode at the initial operation time of the energy storage system.

4. The method of claim 3, wherein the step of setting the operating mode of the energy storage system in accordance with a preset initial mode setting comprises:

when the initial charging state value of the energy storage system is not higher than the operation lower limit, setting the operation mode of the energy storage system as a pure charging mode;

when the initial charging state value of the energy storage system is not lower than the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode;

when the initial charging state value of the energy storage system is lower than the operation upper limit and higher than the operation lower limit, setting the operation mode of the energy storage system to be a pure charging mode or a pure discharging mode;

the initial charging state value is a ratio of residual energy of the energy storage system at an initial operating time to a rated energy capacity, the upper operating limit is a maximum charging state value of the energy storage system charged at a rated power, the lower operating limit is a minimum charging state value of the energy storage system discharged at the rated power, an adjustable output range of the energy storage system corresponding to the pure charging mode is [ -P, 0], an adjustable output range of the energy storage system corresponding to the pure discharging mode is [0, P ], and P is the rated power of the energy storage system.

5. The method of claim 4, wherein the step of determining an operating mode of the energy storage system based on the current state-of-charge value and determining a FM service power regulation range based on the operating mode comprises:

when the current charging state value is not higher than the lower operation limit, setting the operation mode of the energy storage system as the pure charging mode, and setting the frequency modulation service power adjustment range as the adjustable output range of the energy storage system corresponding to the pure charging mode;

when the current charging state value is not lower than the upper operation limit, setting the operation mode of the energy storage system to be a pure discharging mode, and setting the frequency modulation service power regulation range to be an adjustable output range of the energy storage system corresponding to the pure discharging mode;

and when the current charging state value is lower than the upper operation limit and higher than the lower operation limit, keeping the operation mode of the energy storage system unchanged, and setting the frequency modulation service power regulation range as the adjustable output range of the energy storage system corresponding to the operation mode.

6. The method of claim 5, wherein the method further comprises:

when the operation mode of the energy storage system is detected to be a pure charging mode, judging

Whether it is less than (upper operating limit-current state of charge value) E;

if so, keeping the operation mode of the energy storage system as a pure charging mode;

if not, switching the operation mode of the energy storage system to a pure discharge mode;

when the operation mode of the energy storage system is detected to be a pure discharge mode, judging

Whether the current state of charge value is less than (current state of charge value-lower operating limit) E;

if so, keeping the operation mode of the energy storage system as a pure discharge mode;

if not, switching the operation mode of the energy storage system to a pure charging mode;

and E is the rated energy capacity of the energy storage system.

7. The method of claim 2, wherein the step of the genset controller controlling the genset output power based on the first target output value carried by the plan curve is embodied as:

and the generating set controller controls the generating set to output power according to the first target output value carried by the plan curve.

8. The method of claim 1, wherein the step of determining the fm service power adjustment range is specifically:

and determining the frequency modulation service power regulation range to be [ -P, P ], wherein P is the rated power of the energy storage system.

9. The method of claim 8, wherein the step of the genset controller controlling genset output power in accordance with the first target output value carried by the schedule curve comprises:

receiving a deviation compensation quantity sent by the coordination controller or the energy storage system controller, wherein the deviation compensation quantity represents energy loss of the energy storage system in the operation process;

and controlling the generator set to output the sum of the force value and the deviation compensation quantity according to the first target carried by the plan curve.

10. The method of claim 9, wherein the offset compensation amount is obtained by:

when the deviation compensation amount is sent by the energy storage system controller, the manner of obtaining the deviation compensation amount by the energy storage system controller includes:

the energy storage system controller determines a current charging state value and a target charging state value of the energy storage system, and calculates the deviation compensation quantity according to the current charging state value and the target charging state value of the energy storage system;

when the deviation compensation amount is sent by the coordination controller, the manner for the coordination controller to obtain the deviation compensation amount includes:

the coordination controller receives a current charging state value and a target charging state value of the energy storage system, and calculates the deviation compensation amount according to the current charging state value and the target charging state value of the energy storage system, and the current charging state value and the target charging state value of the energy storage system are determined and sent by the energy storage system controller;

or receiving the deviation compensation quantity sent by the energy storage system, wherein the deviation compensation quantity is obtained by the energy storage system controller according to the current charging state value and the target charging state value of the energy storage system through calculation;

the target state of charge value is an average value of an upper operating limit and a lower operating limit, the upper operating limit is a maximum state of charge value of the energy storage system charged at a rated power, and the lower operating limit is a minimum state of charge value of the energy storage system discharged at the rated power.

11. An electricity generating device for supplying power to a power grid, applied to a coordinated controller, the device comprising:

the frequency modulation service power regulation range determining module is used for determining the frequency modulation service power regulation range;

a frequency modulation service power adjustment range sending module, configured to send the frequency modulation service power adjustment range to a power grid dispatching system, so that: the power grid dispatching system generates an AGC dispatching instruction according to a plan curve and the frequency modulation service power regulation range which are obtained in advance, and sends the plan curve and the AGC dispatching instruction to the coordination controller, wherein the plan curve carries a first target output value, the AGC dispatching instruction carries a second target output value, and the second target output value is in the range of [ (the first target output value + the frequency modulation service power regulation range lower limit), (the first target output value + the frequency modulation service power regulation range upper limit) ];

the AGC dispatching instruction receiving module is used for receiving the AGC dispatching instruction and sending the AGC dispatching instruction to the energy storage system controller;

a planned curve receiving module for receiving the planned curve and sending the planned curve to a generator set controller so that: the generating set controller controls the output power of the generating set according to a first target output value carried by the plan curve, detects the current output power of the generating set in real time, and sends the current output power of the generating set to the energy storage system controller so as to enable: and the energy storage system controller controls the output power of the energy storage system according to a second target output value carried by the AGC dispatching instruction and the difference value of the current output power of the generator set.

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