Patent Application
20150254585
The embodiments of the present disclosure relates to a power generation plan creating system and a method thereof that consider an adverse effect when a power quality is changed.
When, in Japan, a change in circumstances of electricity businesses like separation of electric transmission/electric distribution advances in future or when a business in a newly developing country is taken into consideration, if the power quality (i.e., a frequency fluctuation and a voltage fluctuation) can be uniquely set at a power feeding instruction center, etc., of a small-scale power system like a smart grid in accordance with local needs and actual conditions, a further reduction of power generation costs is enabled.
Patent Document 1: JP 4435101 B
However, a power generation plan is so far created based on a presumption that the power quality is within a certain value, and a power generation plan with a change in power quality has not been created, and setting of the optimized power quality has not been performed so far.
An objective of the embodiments of the present disclosure is to provide a power generation plan creating system and a method thereof which can create an optimized power generation plan using a power quality as a parameter in a small-scale power system.
To accomplish the above objective, a power generation plan creating system according to embodiments of the present disclosure is for a small-scale power system, and the power generation plan creating system includes: a condition setting unit setting a time slot of a power generation plan; a power-quality-condition setting unit setting a condition for a frequency fluctuation and for a voltage fluctuation to set a power quality condition; a power generation plan calculating unit setting an operation cost based on the set time slot of the power generation plan and power quality; a blackout rate calculating unit calculating a blackout rate for each blackout time; a risk calculating unit calculating a blackout risk through a predetermined calculation formula based on the blackout rate calculated by the blackout rate calculating unit; and a whole cost integrating unit totaling the blackout risk obtained by the risk calculating unit and the operation cost obtained by the power generation plan calculating unit to integrate a whole cost for each power quality.
In addition, a power generation plan creating method according to embodiment of the present disclosure is for a small-scale power system, and the power generation plan creating method includes: a condition setting step of setting a time slot of a power generation plan; a power-quality-condition setting step of setting a condition for a frequency fluctuation and for a voltage fluctuation to set a power quality condition; a power generation plan calculating step of setting an operation cost based on the set time slot of the power generation plan and power quality; a blackout rate calculating step of calculating a blackout rate for each blackout time; a risk calculating step of calculating a blackout risk through a predetermined calculation formula based on the blackout rate calculated through the blackout rate calculating step; a whole cost integrating step of totaling the blackout risk obtained through the risk calculating step and the operation cost obtained through the power generation plan calculating step to integrate a whole cost for each power quality; and a whole cost minimizing condition outputting step of selecting and outputting a power quality condition that minimizes the whole cost based on whole costs calculated power quality by power quality through the whole cost integrating step.
Specific embodiments of the present disclosure will be explained below with reference to the figures.
A power generation plan creating system 10 of this embodiment includes, in a main block 1, a condition setting unit 11 that sets a time slot, etc., at which a user desires a planning, a power-quality-condition setting unit 12 that sets, for a frequency fluctuation and for a voltage fluctuation, upper/lower limit values, fluctuation range, and a calculation start condition, respectively, a power-quality-condition changing unit 13 that changes those conditions, and a power-generation-plan calculating unit 14 that sets operation costs based on the set planning time slot and power quality.
In addition, the main block 1 includes a blackout rate calculating unit 15 that calculates a blackout rate for each blackout time, a risk calculating unit 16 that calculates a risk using a predetermined calculation formula, a whole cost integrating unit 17 that adds the blackout risk obtained by the risk calculating unit 16 and the operation costs obtained by the power-generation-plan calculating unit 14 to integrate the whole costs, a determining unit 18 that determines whether or not to complete a calculation based on the condition set by the power-quality-condition setting unit 12, and an outputting unit 19 that selects and outputs a power quality condition which minimizes the whole costs.
Still further, the power generation plan creating system 10 is capable of utilizing an external demand predicting system 21. Moreover, the power generation plan creating system includes, as external databases, an operation planning DB 22, a blackout characteristic DB 23, a blackout risk DB 24, and a whole cost DB 25.
The demand predicting system 21 is a system that supplies power generation amount information to the condition setting unit 11. The operation planning DB 22 stores information to be utilized by the power-generation-plan calculating unit 14, and stores, for example, power generator performance information, such a power generation amount, a time, and weather information, facility constraint information, such as the number of activations/deactivations of a power generator, a track constraint, and a minimum electric accumulation amount, and prediction information, such as weather information and a singularity.
The blackout characteristic DB 23 stores data to be utilized by the blackout rate calculating unit 15, and stores characteristics representing a relationship between a frequency fluctuation allowable range and a blackout rate for each blackout time, and characteristics representing a relationship between a voltage fluctuation allowable range and a blackout rate for each blackout time.
The blackout risk DB 24 stores data to be utilized by the risk calculating unit 16, and stores a total damage compensation amount per a blackout time determined according to each time. The whole cost DB 25 stores data on whole costs for each power quality calculated by the whole cost integrating unit 17.
An explanation will now be given of a method for creating a power generation plan through the power generation plan creating system 10 employing the above-explained configuration with reference to
First, when the condition setting unit 11 sets a time slot at which the user of this apparatus desires a planning, the condition setting unit 11 obtains scheduled power generation amount information regarding the set time from the external demand predicting system 21. Example scheduled power generation amount information is expressed as “from Month A, Day B, Hour C, Minute D to Month E, Day F, Hour G, and Minute H: II kWh”.
Next, the power-quality-condition setting unit 12 sets, for each of the frequency fluctuation and the voltage fluctuation that are the barometers of the power quality, an allowable amount in accordance with a time slot (voltage fluctuation (±) allowable range and a frequency fluctuation (±) allowable range. The unit is % or Hz and kV), and the upper or lower limit value of allowable level to start a calculation, and, an margin of the allowable level.
The power-generation-plan calculating unit 14 sets operation costs that minimizes a power generation unit price based on the power generator performance information, the facility constraint information, and prediction information all obtained from the operation planning DB 22, with reference to the set planning time slot and the initial value of the power quality (i.e., the voltage fluctuation allowable range and the frequency fluctuation allowable range at the time of the start of the calculation both set by the power-quality-condition setting unit 12). When the operation costs are set so as to minimize the power generation unit price, e.g., the conventionally well-known scheme disclosed in Patent Document 1 is applicable.
Next, the blackout rate calculating unit 15 checks characteristic data stored in the blackout characteristic DB 23 in advance to calculate the blackout rate for each blackout time.
As illustrated in
In this case, example applicable data that can be stored in the blackout characteristic DB 23 is characterized data through a malfunction simulation using a simulation model which simulates a system configuration in advance. In addition, when a blackout time is set based on a simulation result, the blackout time may be set in accordance with criterion including the blackout time determination table illustrated in
The risk calculating unit 16 calculates a risk by multiplying the blackout rate for each blackout time by a damage compensation amount that is set in accordance with that blackout time. As to the calculation formula of the risk, the following formula (1) is applicable.
In this case, a blackout time n is an assumed blackout time, and can be set as, for example, n=1 second, 5 seconds, 10 seconds, 1 minute, 10 minutes, 1 hour, . . . and 1 day, and the like. In addition, a consumer m represents the total consumers subjected to damage compensation due to a blackout.
The risk calculating unit 16 obtains the risk for each blackout time n through the above-explained formula (1), and accumulates the calculated risks. Information necessary for the calculation is stored in advance in the blackout risk DB 24. Data stored in the blackout risk DB 24 is a total damage compensation amount per a blackout time determined according to each time. As is indicated by the calculation formula (1), this amount is a value obtained by adding the damage compensation amounts of all consumers who are connected to a target system.
In this case, the damage compensation amount differs consumer by consumer and time by time. In the case of, for example, a hospital or a stock market that has a large impact to a society, the damage compensation amount is large. In general, various companies are running their own businesses in the daytime, and thus the damage compensation amount to a blackout is large, but is small in the night. Still further, the damage compensation amount differs depending on the season and the day like the year-end and new-year season and the end of a month with a large number of accountings. This amount should be set in advance based on a research result of a past example damage compensation case, etc.
As an example, it can be set that “in a time slot A-B in a weekday, total damage compensation amount is JP AA YEN/minute per a blackout time, and the breakdown thereof is that, first consumer: JP BB YEN/minute; second consumer: JP CC YEN/minute, and the like”, “in a time slot C-D in a weekday, total damage compensation amount is JP DD YEN/minute per a blackout time, and the breakdown thereof is that, first consumer: JP EE YEN/minute; second consumer: JP DD YEN/minute, and the like”.
Next, the whole cost integrating unit 17 adds the risk due to a blackout which is obtained by the risk calculating unit 16 in accordance with the power quality and the operation costs obtained by the power-generation-plan calculating unit 14 to integrate the whole costs, and stores the integrated data in the whole cost DB 25.
The determining unit 18 determines whether or not to complete the calculation for all cases under the condition set by the power-quality-condition setting unit 12. When the calculation has not been completed yet (step S17: NO), the power-quality-condition changing unit 13 adds or subtracts the margin set by the power-quality-condition setting unit 12 relative to the voltage fluctuation allowable range and the frequency fluctuation allowable range calculated right before, thereby changing (step S19) the power quality condition. Subsequently, the processes subsequent to the step S13 are repeated.
Conversely, when the determining unit 18 determines (step S17: YES) that the calculation has been completed, the outputting unit 19 refers to the whole costs for each power quality stored in the whole cost DB 25, and selects and outputs the power quality condition that minimizes the whole costs.
The power generation plan creating system 10 of this embodiment enables a creation of a power generation plan with details, such as for each time slot, and for each singular day including a holiday, a weekday, and a long holiday season. For example, for a time slot like the night at which a blackout risk is small, a power generation plan for decreasing the power quality and also decreasing the whole costs can be created.
Therefore, it becomes possible to make an operation plan that minimizes the whole costs which include the costs of a blackout risk that is in a trade-off relationship with the power quality, and the operation costs.
A power generation plan creating system 20 of this embodiment employs the same configuration as that of the power generation plan creating system 10 of the first embodiment except that a consumer anti-blackout preparation DB 31 to be utilized by the risk calculating unit 16 is provided outside the main block 1.
The consumer anti-blackout preparation DB 31 stores, as information researched in advance, data relevant to a risk reduction, such as the presence/absence of an uninterruptable power source (UPS) device, a UPS backup time, the presence/absence of batteries, and battery remaining level information (e.g., the capacity and the SOC secured level %).
The power generation plan creating system 20 performs, in the risk calculating step of the step S15, a calculation by the risk calculating unit 16 in consideration of a risk reduction using the consumer anti-blackout preparation DB 31. A risk calculation formula of this embodiment can be expressed as the following formula (2).
In this case, a blackout time n is an assumed blackout time, an can be set as, for example, n=1 second, 5 seconds, 10 seconds, 1 minute, 10 minutes, 1 hour, . . . 1 day, and the like. In addition, a consumer m represents a total consumers subjected to a blackout damage compensation.
When compared with the formula (1) of the first embodiment, the formula (2) differs therefrom that an avoidance coefficient is set. The avoidance coefficient becomes “0” when a consumer carries out a complete blackout avoiding preparation, becomes “1” when no preparation is carried out, and becomes a coefficient between 0 to 1 when a preparation contains an uncertainty. When the uncertainty to avoid a blackout is expressed as a blackout avoidance achievement rate by a probability, the avoidance coefficient becomes “1−blackout avoidance achievement rate”.
The power generation plan creating system 20 of this embodiment considers consumer anti-blackout preparation information in the risk calculating step of the step S15, enabling a risk reduction in accordance with an anti-blackout preparation by the consumer. Hence, when a power supplier further reduces the power quality, the power generation costs can be further suppressed.
A power generation plan creating system 30 of this embodiment employs the same configuration as that of the power generation plan creating system 20 of the second embodiment except that an anti-blackout-facility-data updating unit 41 that automatically updates data relative to the consumer anti-blackout preparation DB 31 is provided outside the main block 1.
The anti-blackout-facility-data updating unit 41 has a function of automatically updating information stored in the consumer anti-blackout preparation DB 31. More specifically, pieces of data on, for each consumer, a UPS backup time (h), and a battery SOC set level (%), and the like are acquired online through a communication line like the Internet. As to the acquisition timing, a consumer may transmit pieces of data, or the anti-blackout-facility-data updating unit 41 may periodically check the data storage of a consumer, and may update the data when there is a change in data contents. Hence, anti-blackout-facility data for each consumer can be updated to the latest information. In addition, operation plan information on, for example, batteries including time information may be obtained from the consumer to update the data contents.
According to the power generation plan creating system 30 of this embodiment, the anti-blackout-facility-data updating unit 41 automatically updates data stored in the consumer anti-blackout preparation DB 31 to the latest information. Therefore, an anti-blackout preparation by the consumer can be precisely reflected on the operation plan.
A power generation plan creating system 40 of this embodiment employs the same configuration as that of the power generation plan creating system 10 of the first embodiment except that, right next to the power-quality-condition setting unit 12, a power-quality-plan setting unit 51 is provided which sets in advance the lower limit value of the power quality for each time slot.
The power-quality-plan setting unit 51 sets, for each of the frequency fluctuation and the voltage fluctuation, the lower limit value of the fluctuation allowable amount as illustrated in, for example,
According to the power generation plan creating system 40 of this embodiment, the power-quality-plan setting unit 51 in a main block 2 sets the lower limit value of the power quality in advance for each time slot, thereby enabling to make an operation plan based on consumer needs. For example, an operation plan that increases the power quality only during the daytime of a weekday at which factories are in operation can be made.
A power generation plan creating system 50 of this embodiment employs the same configuration as that of the power generation plan creating system 20 of the second embodiment except that a blackout-risk-data updating unit 61 that periodically and automatically updates registered information in the blackout risk DB 24 and in the consumer anti-blackout preparation DB 31 is provided outside the main block 1.
The blackout-risk-data updating unit 61 automatically updates the damage compensation amount at the time of a blackout which changes in accordance with, for example, a local development. More specifically, information relevant to a change in the blackout risk calculation condition, such as tenants currently occupying a local commercial facility, and a new construction of a hospital or a school, is acquired online through a communication line like the Internet from an organization like an autonomous community. As to the acquisition timing, a consumer may transmit data, or the blackout-risk-data updating unit 61 may periodically checks the data storage, and may update the data when there is a change in data contents. Hence, the registered information in the blackout risk DB 24 and in the consumer anti-blackout preparation DB 31 can be periodically updated to the latest information. In addition, an update plan that contains time information may be acquired from the consumer to update the data.
According to the power generation plan creating system 50 of this embodiment, the blackout-risk-data updating unit 61 automatically updates the blackout risk information. Hence, when, for example, a hospital is newly constructed or when there is a change in tenants which are currently occupying a commercial facility, the damage compensation amount can be easily corrected.
A power generation plan creating system 60 of this embodiment employs the same configuration as that of the power generation plan creating system 10 of the first embodiment except that, instead of the blackout risk DB 24, a terminal-system blackout risk DB 71 and a terminal-system consumer anti-blackout preparation DB 72 are provided outside the main block 1.
The terminal-system blackout risk DB 71 and the terminal-system consumer anti-blackout preparation DB 72 store registered information divided for each power transmission and for each terminal system that is opened/closed by a consumer terminal breaker of a power company. For example, data on the damage compensation amount for each blackout time is stored in the database and divided for each terminal system such that JP AA YEN/minute for a system A, JP BB YEN/minute for a system B, and JP CC YEN/minute for a system C.
According to the power generation plan creating system 60 of this embodiment, since the blackout risk information is sorted for each terminal system, it becomes possible to create a power generation plan for each terminal system. Hence, when the power demand becomes urgent, an operation that can perform a load interruption on a terminal system in the order of a lower risk is enabled.
(1) In the respective embodiments described above, databases that are the operation planning DB 22, the blackout characteristic DB 23, the blackout risk DB 24, and the whole cost DB 25 are provided outside the main block 1 or the main block 2, but some of or all of the databases may be provided inside the main block 1 or the main block 2 as needed.
(2) In the fourth embodiment (
(3) In the sixth embodiment (
(4) Several embodiments of the present disclosure were explained in this specification, but those embodiments are merely presented as examples, and are not intended to limit the scope and spirit of the present disclosure. The above-explained embodiments can be carried out in various other forms, and permit various omissions, replacements, and modifications without departing from the scope and spirit of the present disclosure. Such embodiments and modifications thereof are within the scope and spirit of the present disclosure, and also within an equivalent range to the subject matter as recited in appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-220164 | Oct 2012 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2013/076680 | 10/1/2013 | WO | 00 |
