JP4845710B2 - Inverter refrigerator control device and power consumption system - Google Patents

Description

  The present invention relates to an inverter refrigerator control device and an electric power consumption system including the inverter refrigerator control device.

  In the refrigerator, in order to increase the operation efficiency, a method of inverter-controlling the rotation speed of the compressor is being adopted. In such an inverter control type refrigerator (inverter refrigerator), since the rotation speed of the compressor is controlled according to the heat load, it is possible to perform an efficient operation according to the heat load. Generally, when the heat load increases, the rotation speed of the compressor increases, and when the heat load decreases, the rotation speed of the compressor decreases. The case where the heat load is large (high load) is immediately after the defrosting operation of the showcase connected to the refrigerator by the refrigerant pipe (within a predetermined time after the defrosting operation is completed) or The case where the internal temperature is higher than the set temperature by a predetermined temperature (for example, 3 ° C) or more.

  A method for controlling the rotation speed of the compressor according to the heat load is already well known. For example, in Japanese Patent Laid-Open No. 10-318644, the cooling state of a showcase is measured, it is determined whether the current refrigerant capacity is insufficient with respect to the heat load of the showcase, and based on the result, the compressor A technique for controlling the rotational speed is disclosed.

  Japanese Patent Laid-Open No. 2002-267309 discloses a technique for increasing the rotational speed of a compressor after the defrosting operation according to the time required for defrosting. Japanese Patent Application Laid-Open No. 8-285425 discloses a technique for controlling the compressor to operate at a rotational speed equivalent to or higher than the commercial rotational speed when a thermal load such as an increase in air temperature increases.

  By the way, when the heat load is temporarily increased, such as a temperature rise after the defrosting operation of the showcase, the original state can be cooled in a short time by increasing the rotation speed of the compressor. However, since there is the most power-efficient rotation speed (hereinafter referred to as the ideal rotation speed) as the rotation speed of the compressor, the power consumption increases when the rotation speed of the compressor is increased from the ideal rotation speed.

The ideal rotation speed of the compressor will be described. As the electric power increases, the rotational speed of the compressor increases, and the flow rate of the refrigerant in the refrigerant pipe increases. At a certain number of rotations, the rate of increase of the refrigerant flow rate with respect to the increase in the number of rotations is greatly increased as compared with other rotation numbers, and as a result, the cooling efficiency is increased. That is, the cooling efficiency with respect to the power consumption becomes the best at a certain rotation speed. This rotational speed is called the ideal rotational speed.
Japanese Patent Laid-Open No. 10-318644 JP 2002-267309 A JP-A-8-285425 JP 2000-78888 A

  Therefore, even if the heat load increases, the power consumption can be reduced by controlling the rotational speed so that it does not become higher than the ideal rotational speed when the showcase is sufficiently cooled even if the rotational speed is reduced. It is possible to maintain the cooling state while reducing the amount.

  Japanese Patent Application Laid-Open No. 2000-78888 discloses a technique that enables operation with high efficiency from the viewpoint of power consumption even at low loads by reducing the input voltage to the inverter control circuit at low revolutions. However, there is no mechanism to judge the situation at high load and suppress the rotation speed.

  The present invention controls an inverter refrigerator that can reduce power consumption within a range in which the showcase can be sufficiently cooled even when the number of revolutions is suppressed, that is, within a range in which the showcase can be kept in a cooled state. An object is to provide an apparatus and a power consumption system.

  The control device for a first inverter refrigerator according to the present invention is a control device for an inverter refrigerator in which the rotation speed of a compressor is automatically controlled according to a heat load in a normal time. Storage means for storing temperature and inverter compressor speed information in the operating state database. When the inverter refrigerator heat load is high, the compressor speed with the best power efficiency is the ideal engine speed. As a determination means for determining whether the ideal rotational speed is larger than the rotational speed corresponding to the current environmental condition in the operating state database, and the ideal rotational speed is more than the rotational speed corresponding to the current environmental condition When it is determined that the rotation speed is large, a control means for controlling the rotation speed of the compressor is provided so that the rotation speed of the compressor becomes an ideal rotation speed. And wherein the Rukoto.

The control device for a second inverter refrigerator according to the present invention is a control device for an inverter refrigerator in which the rotation speed of a compressor is automatically controlled according to a heat load in a normal time. Storage means for saving the temperature, the number of revolutions of the compressor of the inverter refrigerator, and the accumulated power consumption value from the start of the demand time limit to the present in the facility where the inverter refrigerator is installed, the operation state database Based on the power consumption integrated value data stored in the facility, the predicted value of the integrated power consumption value in the facility for the current demand period and the predicted value of the integrated power consumption value in the facility for the next demand period The calculation means for calculating the compressor rotation speed when the heat load of the inverter refrigerator is high. As the ideal rotation speed, the first condition that the ideal rotation speed is larger than the rotation speed corresponding to the current environmental condition in the operation state database, and the predicted value of the power consumption integrated value in the facility in the next demand period It is less than a predetermined target value, or the predicted value of the power consumption integrated value in the facility at the next demand time period is less than the predicted value of the power consumption integrated value in the facility at the current demand time limit. The determination means for determining whether or not both of the two conditions are satisfied, and so that when it is determined that both the first condition and the second condition are satisfied, the rotation speed of the compressor becomes the ideal rotation speed, And a control means for performing rotation speed control with priority on power efficiency.

  Based on the data stored in the operating state database, a means for storing the rotational speed of the compressor in the rotational speed database is provided for each environmental condition defined by the time zone and the outside air temperature. When the load is high, whether the ideal engine speed is greater than the engine speed corresponding to the current environmental conditions in the engine speed database is the ideal engine speed. What to discriminate may be used.

  Based on the data stored in the operation state database, there is provided means for storing the rotation speed of the compressor and the integrated power consumption value in the facility in the rotation speed / power database according to the environmental conditions defined by the time zone and the outside air temperature, As a calculation means, based on the accumulated power consumption value data in the facility stored in the rotation speed / power database, the predicted value of the accumulated power consumption value in the facility at the current demand period and the next demand time period are calculated. Use the one that calculates the predicted value of the power consumption integrated value in the facility, and as the discrimination means, when the thermal load of the inverter refrigerator is high, the rotation speed of the compressor with the best power efficiency is the ideal rotation speed The first condition that the ideal speed is greater than the speed corresponding to the current environmental conditions in the speed / power database and the next demand time limit The predicted value of the power consumption integrated value in the facility is less than or equal to a predetermined target value, or the predicted value of the power consumption integrated value in the facility in the next demand period is the consumption in the facility in the current demand period You may use what discriminate | determines whether both the 2nd conditions that it is below the estimated value of an electric power integrated value are satisfy | filled.

  There may be provided means for canceling the power efficiency priority rotational speed control when a predetermined time has elapsed since the start of the power efficiency priority rotational speed control.

  When the inverter refrigerator is connected to the inverter refrigerator by a refrigerant pipe and the power efficiency prioritized rotational speed control is being performed, the temperature of the showcase is a predetermined temperature from the start of the power efficiency prioritized rotational speed control. As described above, when it is determined that the temperature of the showcase has risen by a predetermined temperature or more from the start of the power efficiency priority rotation speed control and the power efficiency priority rotation speed control, the power efficiency priority rotation speed control is canceled. Means may be provided.

  When a showcase is connected to the inverter refrigerator by refrigerant piping, it is determined whether or not the defrosting operation of the showcase is started within a certain time when the rotational speed control with priority on power efficiency is performed. And a means for releasing the power efficiency priority rotation speed control when it is determined that the showcase defrosting operation is started within a predetermined time.

  The power consuming system according to the present invention performs control different from the normal time in the control of the rotation speed of the compressor of the inverter refrigerator and the inverter refrigerator in which the rotation speed of the compressor is automatically controlled according to the heat load in the normal time. A power consumption system comprising a control device for a refrigerator for controlling the inverter, wherein the control device for the refrigerator is the control device for an inverter refrigerator according to claims 1 to 7.

  According to the present invention, the amount of power consumption can be reduced within a range in which the showcase can be sufficiently cooled even when the number of rotations is suppressed, that is, within a range in which the showcase can be maintained in a cooled state. .

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows power consuming devices provided in a store such as a supermarket and a control device (hereinafter referred to as a controller) that centrally manages these devices.

  The controller 20 is connected to each power consuming device arranged in the store, for example, a showcase 1, a refrigerator 2 for cooling the showcase 1, and the like via a communication line 30. The showcase 1 and the refrigerator 2 are connected by a refrigerant pipe for circulating the refrigerant, and the refrigerant is supplied to the showcase 1 from the refrigerator 2 through the refrigerant pipe. As the refrigerator 2, an inverter refrigerator that employs a method of inverter-controlling the rotation speed of a compressor is used. The refrigerator 2 has a function of controlling the rotation speed of the compressor so that the higher the heat load, the higher the rotation speed of the compressor. Normally, the compressor speed is controlled by this function. In this embodiment, when a predetermined condition is satisfied, the rotation speed of the compressor of the refrigerator 2 is controlled by the controller 20 so as to be an ideal rotation speed.

  The controller 20 is connected to a power meter 11 that measures power consumption. Furthermore, a temperature sensor 12 for measuring the outside air temperature is connected to the controller 20.

  The controller 20 includes a CPU 21. Connected to the CPU 21 are a ROM 22 for storing the program, a RAM 23 for storing necessary data, a rotation speed database 24, an operating state database 25, a timer 26, and the like. The rotation speed database 24 and the operation state database 25 are created in, for example, a rewritable nonvolatile memory. Note that the information on the internal temperature of the showcase 1 is sent to the CPU 21 in the controller 20.

  The rotation speed database 24 stores the rotation speed data (past performance data) of the compressor of the refrigerator 2 for each environmental condition. In this example, as shown in FIG. 2, the environmental condition is defined by the time zone and the outside air temperature. Each square in FIG. 2 represents each environmental condition. In the example of FIG. 2, the time zone is divided at intervals of 30 minutes, and the outside air temperature is divided at intervals of 5 degrees. 2 indicate the environmental conditions in which the time zone is 0:30 to 10:00 and the outside air temperature is 5 ° C to 10 ° C.

  FIG. 3 is a part of the contents of the rotation speed database 24 and stored for environmental conditions in which the time zone is 0:30 to 10:00 and the outside air temperature is 5 ° C. to 10 ° C. The rotational speed data is shown.

  Up to 10 actual data (rotational speed data) can be stored for each environmental condition. When the actual data exceeds 10 for one environmental condition, the oldest data is removed and the latest data is newly added.

  As shown in FIG. 4, the operating state database 25 stores the outside air temperature and the number of rotations of the compressor of the refrigerator 2 at every minute. The rotation speed database 24 is created from information in the operation state database 25 as described later.

  FIG. 5 shows a refrigerator control processing procedure executed by the controller 20 (CPU 21).

  This process is executed every predetermined time, for example, every minute. F is a flag for storing the fact that the rotation speed of the compressor of the refrigerator 2 is being controlled differently from normal (rotational speed control with priority on power efficiency), and is reset at the initial setting when the power is turned on (F = 0).

  First, the operation state of the current device is checked (step S101). For example, the schedule of the defrosting operation of the showcase 1 connected to the refrigerator 2 and the internal temperature of the showcase 1 are examined.

  Next, it is determined whether or not the flag F is set (F = 1) (step S102). If the flag F is reset (F = 0), it is determined whether or not the heat load on the refrigerator 2 is currently in a high load state (step S113). The high load state is immediately after the defrosting operation of the showcase 1 (when it is within a predetermined time after the defrosting operation is completed) or the temperature inside the showcase 1 is α degrees (eg, 3 ° C.) or more from the set temperature. When it is expensive. In addition, when a plurality of showcases are connected to the refrigerator 2, when at least one showcase is immediately after the defrosting operation, or the inside temperature of at least one showcase is α degrees or more than the set temperature. When it is high, it is determined that the heat load on the refrigerator 2 is in a high load state.

  When not in a high load state, the current time, the outside air temperature, and the rotation speed of the compressor of the refrigerator 2 are recorded in the operation state database 25 (step S114), and then the process proceeds to step S115. The outside air temperature is acquired from the temperature sensor 12.

  If it is determined in step S113 that the heat load on the refrigerator 2 is in a high load state, the process proceeds to step S107 in order to determine whether or not to perform power efficiency priority rotation speed control. In step S107, the rotation speed of the compressor corresponding to the current time and the outside air temperature is acquired from the rotation speed database 24, and the rotation speed Ra suitable for the current time and the outside air temperature is checked. When there are a plurality of compressor rotation speeds corresponding to the current time and the outside air temperature in the rotation speed database 24, the maximum value or the average value thereof is set as the rotation speed Ra suitable for the current time and the outside air temperature. .

  Then, the rotation speed Ra obtained in step S107 is compared with an ideal rotation speed (rotation speed with the highest power efficiency) Rb previously grasped as the characteristics of the refrigerator (step S108). The case where the heat load on the refrigerator 2 is in a high load state and Ra <Rb corresponds to the case where a predetermined condition is satisfied. As described above, the rotation speed of the compressor of the refrigerator 2 is Control is performed by the controller 20 so as to obtain an ideal rotational speed.

  If Ra <Rb, after setting the flag F (F = 1) (step S109), control is performed so that the rotation speed of the compressor of the refrigerator 2 becomes Rb (step S110). Then, the process proceeds to step S115. That is, if Ra <Rb, the rotational speed control (rotational speed control with priority on power efficiency) different from the normal time is performed.

  Currently, since the engine is in a high load state, the compressor should be controlled at a rotation speed higher than the rotation speed Ra in the normal load state (probably higher than the ideal rotation speed Rb). On the other hand, it is considered that at least the device (showcase) is going to cool if it is operated at a rotational speed higher than the rotational speed Ra in a normal load state. Therefore, even in a high load state, when the ideal rotation speed Rb is larger than the rotation speed Ra in a normal load state (Ra <Rb), the compressor rotation speed is set to the ideal with priority on power efficiency. The rotation speed is controlled to Rb.

  If Ra ≧ Rb in step S108, the flag F is reset (F = 0) (step S111), and then the power efficiency prioritized rotational speed control (the rotational speed control performed in step S110). Is released (step S112). Then, the process proceeds to step S115. That is, if Ra ≧ Rb, the power efficiency priority rotation speed control is not performed. This is because, in order to cool down the equipment (showcase), it is necessary to operate the compressor at a rotational speed of Ra or higher at a minimum.

  In step S115, it is determined whether or not it is immediately after the time zone defining the environmental condition is switched. Since the time zone that defines the environmental conditions is divided at 30-minute intervals, it is determined whether the time is M hour 00 minutes (M is a natural number from 0 to 23) or just after M hour 30 minutes. . If it is determined that the time period defining the environmental condition is not immediately after switching, the current process is terminated.

  If it is determined in step S115 that the time zone that defines the environmental condition is immediately after switching, the environmental condition that matches the rotational speed in the previous time zone with the environmental condition in the previous time zone. Is stored in the rotation speed database 24 as performance data for (step S116). At this time, the rotational speed in the previous time zone is obtained by calculating an average value of the rotational speed data in the time zone stored in the operation state database 25. Further, the outside air temperature is obtained by calculating an average value of outside air temperature data in the previous time zone stored in the operation state database 25. And this process is complete | finished.

  If it is determined in step S102 that the flag F is set (F = 1), it is determined whether or not a certain time has elapsed since the flag F was last set (step S103). . If the predetermined time has elapsed, the process proceeds to step S111 in order to cancel the power efficiency priority rotation speed control.

  If it is determined in step S103 that a certain time has not elapsed since the time when the flag F was last set, the temperature in the showcase chamber is 1 ° C or higher from the time when the flag F was last set. It is determined whether or not it has risen (step S104). When a plurality of showcases are connected to the refrigerator 2, if at least one showcase has an internal temperature rising by 1 ° C. or more, YES is obtained in step S <b> 104.

  When the temperature of the showcase has increased by 1 ° C. or more since the time when the flag F was last set, the process proceeds to step S111 in order to cancel the power efficiency priority rotation speed control.

  In step S104, if the temperature of the showcase has not risen by 1 ° C or more since the flag F was last set, it is determined whether or not the showcase defrosting operation is scheduled within a certain time. (Step S105). If a plurality of showcases are connected to the refrigerator 2, if at least one showcase is scheduled to be defrosted, YES is determined in step S <b> 105.

  When the defrosting operation of the showcase is scheduled within a certain time, the process proceeds to step S111 in order to cancel the rotation speed control giving priority to power efficiency.

  If the defrosting operation of the showcase is not scheduled within the predetermined time in step S105, it is determined whether or not the heat load on the refrigerator 2 is currently in a high load state (step S106). As described above, the high load state means that immediately after the defrosting operation of the showcase 1 (when it is within a predetermined time after the defrosting operation is completed) or the internal temperature of the showcase 1 is α degrees from the set temperature (for example, 3 ° C) or higher.

  If not in a high load state, the process proceeds to step S111 in order to cancel the power efficiency priority rotation speed control. In the case of a high load state, the process proceeds to step S107 in order to determine whether or not to perform power efficiency priority rotation speed control.

  In the first embodiment, in step S107, the rotation speed of the compressor corresponding to the current time and the outside air temperature is acquired from the rotation speed database 24, and the rotation speed Ra suitable for the current time and the outside air temperature is checked. However, the rotational speed Ra of the compressor corresponding to the current time and the outside air temperature may be acquired from the operation state database 25 to check the number of revolutions Ra suitable for the current time and the outside air temperature. In this case, the rotation speed database 24 can be omitted.

  The second embodiment is an embodiment considering demand control in addition to the first embodiment. Demand control means that the electricity price is determined by the demand peak for the past year (the maximum value among the integrated power values for each demand period), so the power integrated value for the demand period (for example, every 30 minutes) is suppressed, and the demand peak It means to suppress.

  FIG. 6 shows power consuming devices provided in a store such as a supermarket and a controller that centrally manages these devices. In FIG. 6, the same components as those in FIG.

  Compared with the system of FIG. 6 and the system of FIG. 1, the contents of the databases 24A and 25A are different from the contents of the databases 24 and 25 of FIG. Moreover, the control method of the refrigerator by CPU21 is different from FIG.

  The rotational speed / power database 24A stores the power consumption integrated value data and the rotational speed data of the compressor of the refrigerator 2 for each environmental condition. In this example, as shown in FIG. 2, the environmental condition is defined by the time zone and the outside air temperature. Each square in FIG. 2 represents each environmental condition. In the example of FIG. 2, the time zone is divided at intervals of 30 minutes corresponding to the demand time period, and the outside air temperature is divided at intervals of 5 degrees. 2 indicate the environmental conditions in which the time zone is 0:30 to 10:00 and the outside air temperature is 5 ° C to 10 ° C.

  FIG. 7 is a part of the contents of the rotation speed / power database 24A, and stores the environmental conditions in which the time zone is 0:30 to 10:00 and the outside air temperature is 5 ° C. to 10 ° C. The rotation speed data and the power consumption integrated value data are shown.

  Up to 10 actual data (rotation speed data and power consumption integrated value data) can be stored for each environmental condition. When the actual data exceeds 10 for one environmental condition, the oldest data is removed and the latest data is newly added.

  As shown in FIG. 8, the operating state database 25A stores the outside air temperature, the rotation speed of the compressor of the refrigerator 2 and the power consumption integrated value from the start of the demand time limit to the present time for every minute. . At the start of the demand time period, the power consumption integrated value is set to zero.

  FIG. 9 shows a refrigerator control processing procedure executed by the controller 20 (CPU 21).

  Compared with the processing procedure of FIG. 5, in FIG. 9, the processing of step S209 and step S210 is added. Further, since the contents of the databases 24A and 25A are different, the processing contents of steps S216 and S218 are different from the processing contents of steps S114 and S116 of FIG.

  Hereinafter, the processing procedure of FIG. 9 will be described. This process is executed every predetermined time, for example, every minute. F is a flag for storing the fact that the rotation speed of the compressor of the refrigerator 2 is being controlled differently from normal (rotational speed control with priority on power efficiency), and is reset at the initial setting when the power is turned on (F = 0).

  First, the operation state of the current device is checked (step S201). For example, the schedule of the defrosting operation of the showcase 1 connected to the refrigerator 2 and the internal temperature of the showcase 1 are examined.

  Next, it is determined whether or not the flag F is set (F = 1) (step S202). If the flag F is reset (F = 0), it is determined whether or not the heat load on the refrigerator 2 is currently in a high load state (step S215). The high load state is immediately after the defrosting operation of the showcase 1 (when it is within a predetermined time after the defrosting operation is completed) or the temperature inside the showcase 1 is α degrees (eg, 3 ° C.) or more from the set temperature. When it is expensive. In addition, when a plurality of showcases are connected to the refrigerator 2, when at least one showcase is immediately after the defrosting operation, or the inside temperature of at least one showcase is α degrees or more than the set temperature. When it is high, it is determined that the heat load on the refrigerator 2 is in a high load state.

  When not in a high load state, after recording the current time, the outside air temperature, the rotation speed of the compressor of the refrigerator 2 and the power consumption integrated value from the start of the demand time limit to the present time in the operation state database 25A (step S216), The process proceeds to step S217. The outside air temperature is acquired from the temperature sensor 12. The power consumption integrated value from the start of the demand time limit to the present is calculated based on the power consumption acquired from the wattmeter 11 and the power consumption integrated value recorded in the operating state database 25A.

  If it is determined in step S215 that the heat load on the refrigerator 2 is in a high load state, the process proceeds to step S207 to determine whether or not to perform rotation speed control with priority on power efficiency. In step S207, the compressor rotation speed data corresponding to the current time and the outside air temperature is acquired from the rotation speed / power database 24A, and the rotation speed Ra suitable for the current time and the outside air temperature is checked. When there are a plurality of compressor rotation speeds corresponding to the current time and the outside air temperature in the rotation speed / power database 24A, the maximum value or the average value is set to the rotation speed suitable for the current time and the outside air temperature. Ra.

  Then, the rotation speed Ra obtained in step S207 is compared with the ideal rotation speed (rotation speed with the highest power efficiency) Rb, which is previously grasped as the characteristics of the refrigerator (step S208).

If ra <Rb, calculates the excess power predictor Z _n at the current demand time period N, the excess power predictor Z _{n + 1} at the next demand time period (N + 1) (step S209).

It describes a method of calculating the excess power predicted amount Z _n demand time period N. First, the predicted value X _n of the power consumption integrated value in the demand time period N is calculated as follows. The actual power consumption integrated value from the start of the demand time period N to the present is assumed to be x1. Further, the power consumption integrated value data corresponding to the current time and the outside air temperature is acquired from the rotation speed / power database 24A, and the average value thereof is calculated. Let the average value obtained be x2. Further, the remaining time of the current demand time period is assumed to be Tr [minutes]. The predicted value X _n of the power consumption integrated value in the current demand time period is calculated by the following equation (1).

X _n = x1 + {x2 × (Tr / 30)} (1)

When the target value of the power consumption accumulated value for each demand time period and Y, the following equation (2) to calculate the excess power predicted amount Z _n in demand time N.

Z _n = X _n −Y (2)

A method for calculating the power excess prediction amount Z _{n + 1 in} the demand time period (N + 1) will be described. First, a predicted value X _{n + 1} of the power consumption integrated value in the demand time period (N + 1) is obtained. For the predicted value X _{n + 1} , the power consumption integrated value data corresponding to the demand time (N + 1) time and the current outside air temperature is acquired from the rotation speed / power database 24A, and the average value or maximum value thereof is calculated. Can be obtained. Then, the power excess prediction amount Z _{n + 1} in the demand time period (N + 1) is calculated by the following equation (3).

Z _{n + 1} = X _{n + 1} −Y (3)

Next, it is determined whether or not the determination condition “Z _{n + 1} <0” or “Z _n > Z _{n + 1} ” is satisfied (step S210). As will be described later, when the determination condition is satisfied, the power efficiency priority rotation speed control is performed, and when the determination condition is not satisfied, the power efficiency priority rotation speed control is not performed.

Specifically, “the predicted value X _{n + 1} of the power consumption integrated value at the next demand time period is smaller than the target value Y” or “the predicted value X _{n + 1 of the} power consumption integrated value at the next demand time period is the target. If it is greater than or equal to the value Y but the power excess prediction amount Z _{n + 1} is smaller than the power excess prediction amount Z _n in the current demand time period, it is determined that the determination condition is satisfied.

The reason why such a determination condition is provided is that the determination condition is not satisfied, that is, “the predicted value X _{n + 1 of the} power consumption integrated value in the next demand period is equal to or greater than the target value Y and the power When the excess prediction amount Z _{n + 1} is _{equal to} or greater than the power excess prediction amount Zn in the current demand time period ”, the power consumption is integrated in the next demand time period by performing the speed control with priority on power efficiency. This is because the value may increase and the demand peak may increase.

On the other hand, “Even if the predicted value X _{n + 1 of the} power consumption integrated value for the next demand time period is equal to or greater than the target value Y, the power excess predicted amount Z _{n + 1} is the power excess predicted amount Z for the current demand time period. _{In the} case of “smaller than _n ”, the power consumption priority value in the current demand time period can be reduced by performing the power efficiency priority rotation speed control in the current demand time period, and the demand peak may be lowered. Rotational speed control with priority on power efficiency is performed.

  If it is determined in step S210 that the determination condition is satisfied, after setting the flag F (F = 1) (step S211), control is performed so that the rotation speed of the compressor of the refrigerator 2 becomes Rb ( Step S212). That is, when Ra <Rb and the determination condition of step S209 is satisfied, the rotational speed control different from the normal speed (rotational speed control with priority on power efficiency) is performed. Then, the process proceeds to step S217.

  If it is determined in step S208 that Ra ≧ Rb, the flag F is reset (F = 0) (step S213), and then the power efficiency priority rotational speed control (the rotational speed performed in step S212). (Control) is released (step S214). Then, the process proceeds to step S217. If it is determined in step S210 that the determination condition is not satisfied, the process proceeds to step S213.

  In step S217, it is determined whether or not it is immediately after the time zone defining the environmental condition is switched. Since the time zone that defines the environmental conditions is divided at 30-minute intervals, it is determined whether the time is M hour 00 minutes (M is a natural number from 0 to 23) or just after M hour 30 minutes. . If it is determined that the time period defining the environmental condition is not immediately after switching, the current process is terminated.

  If it is determined in step S217 that the time zone defining the environmental condition is immediately after switching, the rotational speed and the power consumption integrated value in the previous time zone are set as the environmental condition in the previous time zone. Is stored in the rotation speed / power database 24A as performance data corresponding to the environmental condition (step S218). At this time, the rotational speed in the previous time zone is obtained by calculating the average value of the rotational speed data in the time zone stored in the operating state database 25A. Further, the power consumption integrated value data in the previous time zone is obtained from the power consumption integrated value in the time zone stored in the operating state database 25A. The outside air temperature is obtained by calculating the average value of the outside air temperature data in the previous time zone stored in the operating state database 25A. And this process is complete | finished.

  If it is determined in step S202 that the flag F is set (F = 1), it is determined whether or not a certain time has elapsed since the flag F was last set (step S203). . If the predetermined time has elapsed, the process proceeds to step S213 to cancel the rotational speed control with priority on power efficiency.

  If it is determined in step S203 that a certain time has not elapsed since the time when the flag F was last set, the temperature in the showcase chamber is 1 ° C or higher from the time when the flag F was last set. It is determined whether or not it has risen (step S204). If a plurality of showcases are connected to the refrigerator 2, if at least one showcase has an internal temperature rising by 1 ° C. or more, YES is obtained in step S <b> 204. When the temperature of the showcase has increased by 1 ° C. or more since the time when the flag F was last set, the process proceeds to step S213 in order to cancel the power efficiency priority rotation speed control.

  In the above step S204, if the temperature of the showcase has not risen by 1 ° C or more since the flag F was last set, it is determined whether or not the showcase defrosting operation is scheduled within a certain time. (Step S205). When a plurality of showcases are connected to the refrigerator 2, if at least one showcase is scheduled to be defrosted, YES is determined in step S205. When the defrosting operation of the showcase is scheduled within a certain time, the process proceeds to step S213 in order to cancel the rotational speed control giving priority to power efficiency.

  If the defrosting operation of the showcase is not scheduled within the predetermined time in step S205, it is determined whether the heat load on the refrigerator 2 is currently in a high load state (step S206). As described above, the high load state means that immediately after the defrosting operation of the showcase 1 (when it is within a predetermined time after the defrosting operation is completed) or the internal temperature of the showcase 1 is α degrees from the set temperature (for example, 3 ° C) or higher.

  If not in a high load state, the process proceeds to step S213 in order to cancel the power efficiency priority rotation speed control. In the case of a high load state, the process proceeds to step S207 to determine whether or not to perform power efficiency priority rotation speed control.

In the second embodiment, in step S207, the rotation speed data of the compressor corresponding to the current time and the outside air temperature is acquired from the rotation speed / power database 24A, and the rotation speed Ra suitable for the current time and the outside air temperature is obtained. Although it is being investigated, the rotation speed Ra of the compressor corresponding to the current time and the outside temperature may be obtained by obtaining the rotation speed of the compressor corresponding to the current time and the outside temperature from the operating state database 25A. Further, in the second embodiment, in step S209, based on the information of the rotational speed and power in the database 24A, and excess power predictor Z _n at the current demand time period N, the power at the next demand time period (N + 1) The excess prediction amount Z _{n + 1} is calculated. Based on the information in the operation state database 25A, the power excess prediction amount Z _n in the current demand period N and the next demand period (N + 1) The power excess prediction amount Z _{n + 1} may be calculated. In this case, the rotation speed / power database 24A can be omitted.

  According to the said Example 1, 2, it becomes possible to drive an inverter refrigerator with an appropriate rotation speed from a viewpoint of power consumption, and can improve power efficiency. That is, the power consumption can be reduced within a range in which the showcase can be sufficiently cooled even when the number of revolutions is suppressed, that is, within a range in which the showcase can be maintained in a cooled state.

  In addition, according to the first and second embodiments, since the internal temperature of the showcase becomes high and the heat load becomes large, the rotational speed control with priority on power efficiency is performed. It is possible to prevent the rotation speed of the machine from being increased. Furthermore, when the elapsed time since the start of the power efficiency priority rotational speed control is a certain time or more, the temperature inside the showcase rises when the power efficiency priority rotational speed control is performed, When it becomes unpreferable to continue the rotational speed control with priority on power efficiency, such as immediately before the defrosting operation, it is possible to appropriately stop the rotational speed control with priority on power efficiency.

  In the second embodiment, since the power consumption integrated value in the next demand time period may increase if the rotation speed control with priority on the power efficiency is performed in the current demand time period, “the power consumption integrated value in the next demand time period” If the predicted value of the value is greater than or equal to the target value and the power excess prediction amount is greater than or equal to the power excess prediction amount in the current demand time period, the power efficiency priority rotation speed control is performed in the current demand time period. I am trying not to. For this reason, it is possible to avoid the danger that the demand peak increases by performing the rotation speed control with priority on power efficiency.

It is a block diagram which shows the power consuming apparatus provided in stores, such as a supermarket, and the control apparatus (controller) which manages these apparatuses centrally. It is a schematic diagram for demonstrating each environmental condition prescribed | regulated by the time slot | zone and external temperature. 4 is a schematic diagram showing a part of the contents of a rotation speed database 24. FIG. 3 is a schematic diagram showing an example of contents of an operation state database 25. FIG. It is a flowchart which shows the control processing procedure of the refrigerator performed by the controller 20 (CPU21). It is a block diagram which shows the power consumption apparatus provided in stores, such as a supermarket, and the controller which centrally manages these apparatuses. It is a schematic diagram which shows a part of content of the rotation speed and electric power database 24A. It is a schematic diagram which shows the example of the content of the driving | running state database 25A. It is a flowchart which shows the control processing procedure of the refrigerator performed by the controller 20 (CPU21).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Showcase 2 Refrigerator 3 Air conditioner 11 Wattmeter 12 Temperature sensor 20 Controller 21 CPU
22 ROM
23 RAM
24 Rotation speed database 24A Rotation speed / power database 25, 25A Operation status database 26 Timer

Claims (8)

In normal times, in the control device of the inverter refrigerator in which the rotation speed of the compressor is automatically controlled according to the heat load,
Storage means for storing at least information on the time, the outside air temperature, and the rotation speed of the compressor of the inverter refrigerator in the operation state database every predetermined time,
When the heat load of the inverter refrigerator is high, the ideal engine speed is higher than the engine speed corresponding to the current environmental conditions in the operating state database, with the compressor speed having the best power efficiency as the ideal engine speed. The discriminating means for discriminating whether or not the engine speed is large, and the compressor speed so that the compressor speed becomes the ideal speed when it is determined that the ideal speed is higher than the speed corresponding to the current environmental conditions. Control means for controlling the number,
A control device for an inverter refrigerator, comprising: In normal times, in the control device of the inverter refrigerator in which the rotation speed of the compressor is automatically controlled according to the heat load,
At a given time, at least the time, the outside air temperature, the rotation speed of the compressor of the inverter refrigerator, and the information on the integrated power consumption from the start of the demand time limit to the present in the facility where the inverter refrigerator is installed Storage means to store in the database,
Based on the power consumption integrated value data in the facility stored in the operation state database, the predicted value of the power consumption integrated value in the facility at the current demand period and the power consumption integrated value in the facility at the next demand time period A calculation means for calculating a predicted value of
When the heat load of the inverter refrigerator is high, the ideal engine speed is higher than the engine speed corresponding to the current environmental conditions in the operating state database, with the compressor speed having the best power efficiency as the ideal engine speed. The first condition that it is large and the predicted value of the power consumption integrated value in the facility at the next demand time limit is less than or equal to a predetermined target value, or the power consumption integrated value in the facility at the next demand time limit Discriminating means for determining whether or not the predicted value satisfies both of the second condition that the predicted value is less than or equal to the predicted value of the power consumption integrated value in the facility at the current demand time period, and the first condition and the second condition Control means that performs power efficiency priority rotation speed control so that the compressor rotation speed becomes the ideal rotation speed when it is determined that both are satisfied.
A control device for an inverter refrigerator, comprising: Based on the data stored in the operation state database, it has means for storing the compressor rotation speed in the rotation speed database according to the environmental conditions defined by the time zone and outside air temperature,
When the inverter refrigerator has a high heat load, the discriminating means uses the compressor rotation speed with the best power efficiency as the ideal rotation speed and the ideal rotation speed from the rotation speed corresponding to the current environmental conditions in the rotation speed database. 2. The control apparatus for an inverter refrigerator according to claim 1, wherein the controller determines whether or not the number is larger. Based on the data stored in the operation state database, the compressor rotation speed and the integrated power consumption value in the facility are stored in the rotation speed / power database according to the environmental conditions defined by the time zone and outside temperature. And
The calculation means is based on the accumulated power consumption value data in the facility stored in the rotation speed / power database, and the predicted value of the accumulated power consumption value in the facility at the current demand period and the facility in the next demand time period. To calculate the predicted value of the power consumption integrated value in the
When the inverter refrigerator has a high heat load, the discrimination means uses the rotation speed of the compressor with the best power efficiency as the ideal rotation speed, based on the rotation speed corresponding to the current environmental conditions in the rotation speed / power database. The first condition that the ideal rotation speed is larger and the predicted value of the power consumption integrated value in the facility at the next demand time period is less than or equal to a predetermined target value, or the facility at the next demand time period It is discriminate | determined whether both the 2nd conditions that the predicted value of the power consumption integrated value of this is below the predicted value of the power consumption integrated value in the facility in this demand time period are satisfy | filled. The control device for an inverter refrigerator according to claim 2. 5. The inverter refrigerator according to claim 1, further comprising means for canceling the rotational speed control prioritizing power efficiency when a predetermined time has elapsed since the rotational speed control prioritizing power efficiency was started. Control device. Having a showcase connected to the inverter refrigerator by refrigerant piping;
Means for determining whether or not the temperature of the showcase has risen above a predetermined temperature from the start of the power efficiency priority rotation speed control when the power efficiency priority speed control is performed; and 5. The apparatus according to claim 1, further comprising means for canceling the rotational speed control with priority on power efficiency when it is determined that the temperature of the showcase has increased by a predetermined temperature or more from the start of the rotational speed control. Inverter refrigerator control device. Having a showcase connected to the inverter refrigerator by refrigerant piping;
Means for determining whether or not the defrosting operation of the showcase is started within a predetermined time and the defrosting operation of the showcase is started within the predetermined time when the rotational speed control with priority on power efficiency is performed. 5. The control device for an inverter refrigerator according to claim 1, further comprising means for canceling the rotational speed control giving priority to power efficiency when it is determined as follows. An inverter refrigerator that automatically controls the rotation speed of the compressor according to the heat load in the normal time, and a control device for the refrigerator that performs control different from the normal time in the control of the rotation speed of the compressor of the inverter refrigerator A power consumption system comprising: an inverter refrigerator control device according to claim 1, wherein the refrigerator control device is an inverter refrigerator control device according to claim 1.

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