JP3201812U - Power control device - Google Patents

Abstract

A power control apparatus capable of automatically controlling the operation of a plurality of compressors in a general purpose regardless of the scale. A plurality of compressors C (C1, C2,...) That are confirmed to be operating are controlled from a threshold value that is set based on the total power consumption or current value permitted by the power contract. The control signal for stopping or restarting each compressor is generated based on the detection information, and the control signal is sequentially received on each compressor side according to a predetermined priority set for each compressor. The compressor is stopped or restarted, and after the stop or restart is executed, the compressor is not restarted or stopped for a certain period of time, and is specified by the type of the power contract. Provided is a power control device including a switching unit that can selectively receive each control signal generated corresponding to a received power voltage. [Selection] Figure 1

Description

  The present invention relates to a power control device that controls stop or restart of a plurality of compressors to be supplied with power according to a predetermined power contract, and in particular, a compressor (compressor) such as a plurality of air conditioners and refrigerators. It is for automatically controlling the operation of the machine.

  Under the circumstances where the external environment related to energy resource procurement is uncertain, electric power consumers (mainly companies) are becoming more aware of whether electric power can be sufficiently supplied regardless of the size. Especially in the summer, when power consumption peaks during the year, the main issue is the balance between power supply and demand due to the operating rate of air conditioners and the like (more specifically, compressors) that account for a large portion of power consumption. It is one. In addition, air conditioners usually do not always operate, and even if they are stopped within a certain period of time, even if they are stopped, there may be practically no change in sensible temperature, so there is room for adjustment of operation.

  In the case of a relatively large power consumer (receiving voltage 6600V), install a cubicle in the company and calculate the average power (demand value) in the so-called demand time limit (30 minutes) unit in the range of 50 kW or more and less than 500 kW. The contract power is determined based on the monthly maximum demand value in the past year, and a high-voltage power receiving contract (also referred to as “demand contract” or “actual contract”) is concluded with the power company.

  Therefore, in the case of the high-voltage power receiving contract, a target of power consumption is set in advance on the power consumer side, a warning is given when the set target power is likely to be exceeded, and the plurality of the targets are set according to a preset priority order. The demand value is reduced by adopting a demand controller that controls the operation of the compressor.

  Conventionally, the demand controller includes, for example, an operation monitoring unit of the compressor, a blocking unit for forcibly blocking an operation state, and a timing control unit for controlling operation timing of the blocking unit, and the timing control A first means for entering a control mode every predetermined control period; a second means for waiting until a predetermined time has elapsed after shifting to an operation state in the control mode; and For example, there has been proposed a power control device including a third means for operating the shut-off unit, waiting for the shut-off unit to operate if it is in a non-operating state, and further operating the shut-off unit after the predetermined time has elapsed. (For example, refer to Patent Document 1).

  On the other hand, in the case of a small-scale electric power consumer (receiving voltage 100V-200V), electric power is supplied after being transformed through a transformer provided by an electric power company. Therefore, the contract for determining the contract power is a low-voltage power reception contract according to the power reception voltage. In particular, in order to reduce the basic charge, a main switch contract is often concluded that calculates contract power based on the capacity of the main switch that limits the maximum current.

  In the case of a main switch contract, if a current exceeding the rated current specified by the electronic breaker flows on the main switch (electronic breaker) side to be installed, it will be shut off after the lapse of a certain time specified by the JIS standard. The configuration is completely different from the control by the demand controller.

  Conventionally, a current value measuring unit and a time measuring unit for measuring the time when the measured current value flows are determined in advance for a small-scale electric power consumer receiving power supply by the main switch contract. A current breaker (electronic breaker) having a current breaker that cuts off a current when a current larger than a predetermined value flows within a predetermined time, an air conditioner having a compressor, and the air conditioner An air conditioner current value measuring unit that measures the supplied current value, an air conditioner time measuring unit that measures the elapsed time of the current value that is operating the air conditioner, and an elapsed time that is measured by the air conditioner time measuring unit. Has been proposed (see, for example, Patent Document 2), which includes an air conditioner controller having a stop signal output unit that outputs a stop signal for stopping the compressor when a predetermined time is reached. .)

Japanese Patent No. 3037939 Japanese Patent Laying-Open No. 2015-117841

  By the way, when the electric power consumer expands or contracts the business scale, the contract electric power may be changed, and the type of contract concluded with the electric power company may be changed. In this case, for example, when the contract is changed from the main switch contract to the demand contract, the voltage control method is completely different. Therefore, it is necessary to purchase a dedicated device (cubicle), which increases the initial cost burden. There was an inconvenience.

  Further, according to the prior art described in Patent Document 2 as the power control device in the main switch contract, the controller of the air conditioner (compressor) only measures the current value and elapsed time of one air conditioner. Because it is for outputting a stop signal, and is not for monitoring and controlling the total amount of power of the plurality of air conditioners like the demand controller in the high-voltage power contract, it is small-scale. However, it must be said that the operation adjustment for power consumers who use multiple air conditioners is incomplete.

  Therefore, the present invention is for solving the above-described problems, and provides a power control apparatus capable of automatically controlling the operation of a plurality of compressors for general purposes regardless of the size of power consumers. The purpose is to do.

In order to achieve the above object, a power control apparatus according to the present invention is a power control apparatus that controls stop or restart of a plurality of compressors to be supplied with power according to a predetermined power contract,
Monitoring means for confirming the operating state of each compressor;
Detecting means for detecting the necessity of control from a preset threshold value based on a total of power consumption or current value permitted by the power contract for all of the plurality of compressors confirmed to be operating; ,
A signal generation means for generating a control signal for stopping or restarting each compressor according to the detected information, and transmitting the control signal to the compressor to be stopped or restarted;
Receiving means for sequentially receiving the control signal on each compressor side by a predetermined priority set in each compressor;
Command means for stopping or restarting the compressor specified by the received control signal;
Protective means for preventing restart or stop of the compressor within a predetermined time after the stop or restart is executed,
Most preferably, the signal generating means includes first switching means that allows the receiving means to selectively receive each control signal generated corresponding to the received voltage specified by the type of the power contract. Main features.

  Here, the type of the power contract is typically a demand contract as a high voltage power reception contract and a main switch contract as a low voltage power reception contract.

  As described above, the power control device according to the present invention switches the first switching means so that the amount of power used for a plurality of compressors used under either a high-voltage power reception contract or a low-voltage power reception contract. Can be controlled. That is, when the first switching unit has selected to be able to receive a control signal corresponding to the high-voltage power reception contract, the detection unit obtains a pulse signal from a watt hour meter via a pulse detector, Current power amount calculation means for calculating the amount of power used within the time period set in the predetermined time unit from the acquired pulse signal, and when the current load state continues based on the calculated current power amount Predicted power amount calculation means at the end of the time limit, and the amount of power necessary for stopping or restarting to reach the target power amount at the end of the time limit arbitrarily set based on the calculated predicted power amount Adjusting power amount calculation means for calculating the consumption power of the plurality of compressors when the predicted power amount exceeds or exceeds the target power amount. Electric Or when it becomes more adjustment limit value to set the sum of the current value as adjustable power, the predetermined elapsed time within the time period, generates a control signal for the compressor stops in accordance with said priority. The threshold is determined based on the calculated predicted power amount and the adjusted power amount.

  Here, with respect to the timing of generation and transmission of the reactivation control signal, a mode for generating and transmitting under a predetermined condition within the same time period when the stop control signal is transmitted, and a time period when the stop control signal is transmitted And a mode for generating and transmitting a reactivation control signal at the start of a time period that comes next, and the priority order for the generation and transmission order of the reactivation control signal. It is good also as a structure which has a 1st restart setting means which can set any one of the mode which produces | generates and transmits in order with high order, and the mode which produces | generates and transmits in order with the said low priority.

  On the other hand, when the first switching means has selected to receive a control signal corresponding to the low-voltage power reception contract, the detection means acquires the alarm signal set in the main switch, and the signal The generation means includes conversion means for converting the alarm signal into the control signal in accordance with a predetermined detection current capacity and overcurrent determination conditions. With this configuration, even in a low-voltage power reception contract including a main switch, voltage control for a plurality of compressors can be performed as in the high-voltage power reception contract. The threshold in the case of a low voltage power reception contract is determined based on the detected power capacity and an overcurrent determination condition.

By the way, the main switch has different types depending on the output condition of the alarm signal. Therefore, it may be configured to include second switching means that can selectively receive the alarm signals of a plurality of different main switches.

  In the case of the low-voltage power reception contract, with respect to the order of generation and transmission of the control signal for reactivation, a mode for generating and transmitting in the order of high priority, and a mode of generating and transmitting in the order of low priority It is good also as a structure which has a 2nd restart setting means which can set any one of these.

  The power control device according to the present invention can automatically control the operation of a plurality of compressors regardless of the size of the power consumer, so that the power contract is a high voltage power reception contract or a low voltage power reception contract. Even if it changes, it can respond with the same apparatus, and there exists an effect that the cost of the capital investment regarding control of compressors, such as several air conditioners, can be held down.

Moreover, the power control apparatus according to the present invention can be used universally by the first switching unit and the second switching unit without depending on the type of power contract and the type of main switch (electronic breaker). Therefore, there is an effect that a highly expandable device can be provided.

FIG. 1 is a block schematic diagram of a power control apparatus according to the present invention. FIG. 2 is a block configuration diagram of a control signal output unit of the power control device, (a) is a block configuration diagram of a high voltage power side output unit, and (b) is a block configuration diagram of a low voltage power side output unit. . FIG. 3 is a graph showing the current power amount P. As shown in FIG. FIG. 4 is a graph showing the predicted power amount R. FIG. 5 is a graph showing the adjustment power amount U. FIG. 6 is a diagram showing time-series control conditions for stopping and restarting the compressor. FIG. 7 is a conceptual diagram showing the restart setting mode in relation to the demand time period after the compressor is stopped. FIG. 7A is a mode in which the operation is restarted within the current demand time period, and FIG. It is the figure which showed the mode which restarts with the start of time limit. FIG. 8 is a conceptual diagram showing the restart setting mode in relation to the priority order after the compressor is stopped. FIG. 8A is a mode in which restart is performed from the lowest priority order, and FIG. 8B is a priority order. It is the figure which showed the mode which restarts from the higher one. FIG. 9 is a power control processing flowchart in the case of a high-voltage power receiving contract. FIG. 10 is a flowchart of power control processing in the case of a low voltage power reception contract.

  Referring to FIG. 1, reference numeral 1 denotes a power control apparatus according to the present invention. The power control apparatus 1 can control the operation of a plurality of compressors such as a plurality of air conditioners used under a high voltage power reception contract and a plurality of compressors such as a plurality of air conditioners used under a low voltage power reception contract. Versatility.

Here, the types of power contracts include, for example, a special high voltage power reception contract and a demand contract (actual amount contract) as the high voltage power reception contract, and a load facility contract and a main switch contract as the low voltage power reception contract. The power control device according to the present invention can control any operation of a plurality of compressors such as a plurality of air conditioners in any contract. It demonstrates as what controls the operation | movement of compressors, such as several air conditioner in a main switch contract. The power control device according to the present invention is intended to control the operation of compressors such as a plurality of air conditioners. In the present embodiment, the compressors of a plurality of air conditioners will be described below. This will be described as a control target example.

In the case of the demand contract, a pulse signal can be acquired via a pulse detector D from a watt-hour meter E provided by an electric power company. There are pulse detectors D that can detect timed pulses in addition to detecting electric energy pulses (as of 2015, in the case of Kansai Electric Power), and the synchronization processing described later is different, but can be handled in either case. As described above, two types of input terminals may be set in advance.

On the other hand, in the case of a main switchgear contract, an air conditioner and other load facilities are connected from the switchboard S through an electronic breaker B installed in accordance with a contract with an electric power company. When a current exceeding the rated current determined by the electronic breaker B flows, the electronic breaker B shuts off after a lapse of a fixed time defined by the JIS standard, but transmits an alarm signal before shutting off. Therefore, when power control is performed under a main switch contract, the alarm signal may be acquired instead of the pulse signal in the demand contract.

The power control device 1 is installed between the pulse detector D or the electronic breaker B and a plurality of compressors C (C1, C2,...).

The pulse signal transmitted from the pulse detector D is acquired by the high-voltage power side output unit 11, the detection unit 111 executes arithmetic processing described later, and the signal generation unit 112 receives the result of the arithmetic processing and receives the compressor C. A signal for controlling is generated.

On the other hand, the alarm signal transmitted from the electronic breaker B is acquired by the low-voltage power side output unit 12, detects a signal corresponding to the type of the electronic breaker B installed in the detection unit 121, and the signal generation unit 122 Based on the detected signal, the signal is converted into a signal for controlling the compressor C.

In addition, the said arithmetic processing and signal generation of the high voltage electric power side output part 11 and the low voltage electric power side output part 12 are performed by CPU (not shown) mounted in each.

The control signal generated by the signal generation unit 112 or the signal generation unit 122 is transmitted to the control unit 13 (13a, 13b...) Connected to each of the plurality of compressors C (C1, C2...). The communication means between the high-voltage power-side output unit 11 or the low-voltage power-side output unit 12 and the control unit 13 uses serial communication capable of multidrop connection, thereby transmitting / receiving signals to / from a plurality of compressors C. Or become possible. For example, by using RS-485, up to 32 compressors C can be connected.

The control unit 13 includes a first switching unit 131 that can receive different types of control signals. Here, in the present embodiment, the different types of control signals are a control signal transmitted from the high-voltage power output unit 11 and a control signal transmitted from the low-voltage power output unit 12. In order to selectively receive the two control signals, for example, a dip switch may be mounted and either one may be selected by ON / OFF. 1 indicates that the first switching unit 131 selects reception of the control signal of either the high-voltage power-side output unit 11 or the low-voltage power-side output unit 12.

The control unit 13 includes a receiving unit 132 that can receive the control signal selected by the first switching unit 131. The receiving unit 132 may be received by the communication unit, and may have an input terminal corresponding to the number of control signals that can be selected (two in this embodiment).

The control unit 13 includes a monitoring unit 133 that monitors the operating state of the compressor C to be controlled. The state of stop and operation may be monitored and externally displayed by a monitor LED or the like.

According to the control signal received by the receiving unit 132, a stop / restart command is issued from the command unit 134 to the compressor C connected to each control unit 13 to control the operation of the compressor C. In addition, the instruction | command part 134 is comprised by the relay circuit, and should just stop and restart the compressor C by turning ON / OFF a relay circuit according to the said control signal.

Normally, the compressor C (air conditioner) itself also has a function of automatically stopping and restarting for temperature adjustment. When the operation control is mutually operated, the stop and re-operation are repeated in a short time, and the idling time required by the compressor C is not sufficiently given, and as a result of applying a load, it may cause a failure. is there. Therefore, the control unit 13 includes a protection unit 135 that performs control so as not to be restarted or stopped for a set period of time when the control unit 13 receives a stop or restart control from the command unit 134.

The control unit 13 includes a general-purpose function that can be connected to an output device that transmits a control signal different from the control signal described in the present embodiment, separated from the high-voltage power-side output unit 11 and the low-voltage power-side output unit 12. It may be a thing. For example, the dip switches may be mounted corresponding to the number of the output devices, and the input terminals of the receiving unit 132 may be provided corresponding to the number.

FIG. 2 is a detailed block configuration diagram of each output unit of the control signal of the power control apparatus. FIG. 2A is a block configuration diagram of the high voltage power output unit 11. In the case of a demand contract, in order to manage the power consumption (demand), the power amount (average power in the demand time period) within the demand time period (30 minutes from 0 minutes per hour, 30 minutes from 30 minutes per hour) is the control signal. In order to generate the data, it becomes data necessary for calculation of a threshold value to be described later. Therefore, time-synchronized processing is required between the high-voltage power output unit 11 and each control unit 13. Therefore, a synchronization processing unit 113 may be provided to synchronize both watches. Specifically, a real-time clock may be mounted as a peripheral circuit, and a command may be issued from the synchronization processing unit 113 to synchronize the clock of each control unit 13 via the communication unit. The synchronization processing unit 113 may be set to directly synchronize with the timed pulse when the pulse detector D outputs a timed pulse, but when the pulse detector D outputs an electric energy pulse, What is necessary is just to set synchronizing with the frequency of the AC power supply input input by a predetermined time interval.

In addition, a display unit 114 may be provided to perform various setting inputs in the detection unit 111 and the signal generation unit 112. The display unit 114 includes, for example, a liquid crystal display and displays the current status, as well as a demand value (previous demand value and maximum demand value), an integrated power amount, a constant value necessary for calculation described later, and a plurality of controls. When inputting the specification of the unit 13 (channel setting), the priority of control to be described later, and the like, it can be displayed to confirm the input contents.

Furthermore, an alarm unit 115 that outputs an alarm by a buzzer and / or a lamp according to the status of the power usage amount from the result obtained by the arithmetic processing described later may be provided.

  When the detection unit 111 acquires a pulse from the pulse detector D, the detection unit 111 performs a predetermined calculation in order to determine whether control is necessary from a preset threshold value. In this Embodiment, it has the present electric energy calculating part 111a, the estimated electric energy calculating part 111b, and the adjustment electric power calculating part 111c as what performs this calculation. Hereinafter, the contents of the arithmetic processing will be described with reference to FIGS. 3, 4 and 5.

  The current power amount calculation unit 111a calculates the current power amount each time a pulse input from the pulse detector D is detected from the start of the demand time limit. The current power amount P (kW) is calculated by the following calculation formula.

  Here, the demand time period means 30 minutes each from 00:00 to 29:59 and from 3:30 to 59:59 (30 minutes is 1 time and reset to 0 after the end of 1 time) To do). The VCT ratio refers to a conversion constant determined by a connected watt hour meter or pulse converter when power is obtained from a power amount pulse. The pulse constant refers to the number of pulses per electric energy, and the unit is pulses / kWh.

  FIG. 3 is a conceptual diagram visibly showing the current power amount P, that is, a graph showing the accumulated power amount per demand time unit with the elapsed time (demand time period) on the horizontal axis and the power amount on the vertical axis. is there. FIG. 3 shows the current power amount P at the elapsed time t.

  When the current load state continues, the predicted power amount calculation unit 111b calculates the power amount at the end of the demand time period. The predicted power amount R (kW) is calculated by the following calculation formula.

  Here, P is the current power amount calculated by Equation 1 above. t refers to the elapsed time of the demand time period. Δt is the pulse integration time, and is a value that changes from the start of the demand time period to 3 minutes from the start of the remaining time period to 3 minutes and from 1 minute to the end of the time period from the remaining time of 3 minutes. ΔP is an increment of the electric energy for Δt minutes, which can be calculated by substituting “the number of input pulses from the start of the demand time period to the current time” in the above-mentioned equation 1 with “the number of pulses for Δt minutes”.

  FIG. 4 is a conceptual diagram visibly showing the predicted electric energy R, that is, the elapsed time (demand time limit) on the horizontal axis and the electric energy on the vertical axis, and the slope of the graph is calculated from a minute change in the current electric energy. The amount of power R at the end of the demand time period is shown. For example, the predicted power amount R may be calculated every 10 seconds and displayed on the display unit 114. Note that the target power amount Q in FIG. 4 is set in advance with a predetermined value.

  The adjusted power calculation unit 111c calculates, for the predicted power amount, a stop or restart power amount required to reach the target power amount Q (kW) at the end of the demand time period. The adjustment power amount U (kW) is calculated by the following calculation formula.

Here, R is the predicted power amount calculated by Equation 2 above. Q is a target power amount, and is set at a predetermined value in advance as described above. t is the elapsed time of the demand time period.

FIG. 5 is a conceptual diagram visually showing the adjusted power amount U, that is, the difference between the predicted power amount R and the target power amount Q, with the elapsed time (demand time period) on the horizontal axis and the power amount on the vertical axis. The adjustment power amount U is calculated from the above. Similarly to the predicted power amount R, the adjusted power amount U may be calculated every 10 seconds and displayed on the display unit 114, for example.

The calculated current power amount P, predicted power amount R, and adjusted power amount U are used as operating conditions of the alarm unit 115 as described below.

In the adjustment alarm based on the adjusted electric energy U, for example, the predicted electric energy R exceeds the target electric energy Q, and the adjusted electric energy U becomes equal to or greater than the adjustment alarm value (adjustment limit value) shown in FIG. Can be set to occur. This is an alarm that the target power amount Q is reached at the end of the demand period if the power consumption corresponding to the adjustment alarm value is stopped at the present time.

Further, the prediction warning based on the predicted power amount R can be set to occur when the predicted power amount R exceeds the target power amount Q, for example. This is an alarm indicating that if the remaining time of the demand time period is operated as it is, the target power amount Q is exceeded at the end of the demand time period.

In addition to the above, an alarm may be generated even when a preset fixed alarm issue value is exceeded (not shown). For example, 80% of the target power amount Q may be set as the fixed alarm issue value.

FIG. 6 is a diagram showing, on the timeline, the correlation with the presence / absence of transmission of a stop control signal when the conditions for generating the adjustment alarm and the prediction alarm are satisfied. The calculated current power amount P, predicted power amount R, and adjusted power amount U are sent from the detection unit 111 to the signal generation unit 112, and a stop control signal is generated in conjunction with the alarm generation condition. Is transmitted to the unit 13.

From the start of the demand time limit to the remaining time of 24 minutes, no alarm is generated by the alarm mask, and accordingly, a control signal for instructing the stop of the compressor C is not generated. Next, for the remaining time from 24 minutes to 5 minutes, when the prediction alarm is generated, the stop control signal linked to the prediction alarm is not generated. However, when the adjustment alarm is generated, the stop control signal is linked to the adjustment alarm. Is generated and transmitted, and a control signal for stopping one compressor C at intervals of 30 seconds is transmitted according to the priority order described later until the adjustment alarm is canceled. For the remaining time of 5 minutes to 30 seconds, when a prediction alarm occurs, a stop control signal linked to the prediction alarm is not generated, but when an adjustment alarm occurs, a stop control signal is generated and transmitted in conjunction with the adjustment alarm. At the same time, a stop control signal is transmitted at intervals of 30 seconds at the same time for each group of compressors C set in advance according to the priority order described later until the adjustment alarm is canceled. The remaining time is 30 seconds to 10 seconds. When a prediction alarm or adjustment alarm occurs, the control signal for stoppage is generated and transmitted in conjunction with the prediction alarm or adjustment alarm until the prediction alarm or adjustment alarm is canceled. A stop control signal is transmitted at an interval of 30 seconds at the same time for each group of compressors C set in advance according to the priority order described later. If the remaining time is less than 10 seconds, the stop control signal is not generated or transmitted.

In the present embodiment, the control signal is generated and transmitted in conjunction with the generation / release of the alarm, but the present invention is not intended to be limited to this. Therefore, the generation / transmission timing of the alarm and the generation and transmission timing of the control signal may be performed with a predetermined time difference, and the control signal may be generated and transmitted under conditions different from the generation of the alarm.

As described above, after the stop control signal is generated and transmitted according to the remaining time, the restart control signal can be set in advance by the first restart setting unit 116. In the present embodiment, the generation and transmission timing of the restart control signal and the setting of the restart control signal generation and transmission order can be selected as follows.

First, as for the timing of the control signal for restart, as shown in FIG. 7, when the compressor C once stopped meets the restart condition within the same demand period, it is generated and transmitted (FIG. 7 (a)). Compressor C, which has been stopped, is selected from two modes (FIG. 7B) in which the current demand period ends and the next demand period starts and is generated and transmitted in a fixed manner. It is possible.

In addition, when FIG. 7A is selected, as for the relationship with the stop control signal, the time zone of the alarm mask is the compressor that could not be restarted in response to the stop control signal within the previous demand time period. C restarts, and each stage from the remaining time of 24 minutes to 10 seconds restarts when the adjustment power amount is equal to or greater than the adjustment alarm value × 2. On the other hand, when FIG. 7B is selected, only the alarm mask time zone is restarted at the start of the demand time limit, but after the remaining time of 24 minutes, it is not restarted as long as it is within the demand time limit.

Next, regarding the order of the control signal for re-operation, as shown in FIG. 8, a mode in which operation is resumed from a compressor C with a lower priority (to be described later) (FIG. 8A), from the compressor C with a higher priority. It is possible to select from two modes of the re-operation mode (FIG. 8B).

Returning to FIG. 2, FIG. 2B is a block configuration diagram of the low-voltage power side output unit 12. The low-voltage power-side output unit 12 is configured to comply with an alarm signal output condition that prevents the installed electronic breaker B from being interrupted (tripped), and is controlled by a demand time limit like the high-voltage power-side output unit 11. Absent.

By the way, the electronic breaker B has different types of current capacity to be detected and overcurrent determination conditions regarding the trip conditions. Therefore, the detection unit 121 includes a second switching unit 121a in order to correspond to the type of the electronic breaker B. For example, the second switching unit 121a may be configured such that each connector for connecting an alarm output signal cable of each electronic breaker B can be connected and the electronic breaker B can be selected by a setting dip switch.

When the alarm signal of the electronic breaker B selected by the second switching unit 121a is detected by the detection unit 121, the signal generation unit 122 generates a control signal for stopping and restarting the compressor C based on the detected signal. Here, since the detected signal is an alarm signal of the electronic breaker B, the conversion unit 122a of the signal generation unit 122 converts the detected signal into a control signal for stopping and restarting the compressor C.

The conversion unit 122a receives the alarm signal detected by the detection unit 121, and according to the detected current capacity of the overcurrent (for example, the percentage of the overcurrent with respect to the rated current), When the predetermined trip operation waiting time condition of the electronic breaker B is satisfied, a control signal for stopping the compressor C may be generated. Here, the predetermined trip operation waiting time condition is, for example, when 90% or more of the trip operation waiting time has elapsed in the overcurrent state, or when less than 5 minutes have elapsed until the trip operation starts. .

The high voltage power output unit 11 is provided with a display unit 114 composed of the liquid crystal display for confirming various settings. However, in the low voltage power output unit 12, the setting for generating the control signal is as described above. Therefore, a display unit such as a liquid crystal display is not required. Therefore, the display unit 123 of the low-voltage power-side output unit 12 only needs to perform, for example, an operation display of the conversion unit 122a and a confirmation display of a communication state with the control unit 13. Specifically, it may be anything that displays a status by turning on or blinking an LED.

Also, the low-voltage power output unit 12 can set the restart condition in the second restart setting unit 124 as in the high-voltage power output unit 11. However, since the demand time limit is not used in setting the conditions, the timing of the reactivation control signal is limited to the one that is generated and transmitted when the reactivation condition is satisfied, and only the order of the reactivation control signal is shown in FIG. It is only necessary to enable selection of the same mode as described in the above.

Hereinafter, the power control processing steps by the power control apparatus 1 in the case of a demand contract will be described with reference to FIG.

First, as a pre-process for executing the power control process, priority order setting will be described below. In the high voltage power output unit 11, a unique individual number (channel) is set for the control unit 13 connected to each of the plurality of compressors C, and the channel set for each control unit 13 is also set. To do. For channel setting, if a dip switch and a rotary switch are mounted and the both are combined, for example, as described above, a unique individual number can be set for the control unit 13 connected to a large number of the compressors C of about 32 units. Is possible. The smaller individual number has a higher priority. Furthermore, a plurality of control units 13 may be grouped and a group number may be set as a higher rank of the individual number. In the case of setting the group number, the priority order may be set so that the smaller group number has the higher priority order, and within the same group, the lower individual number is set to have the higher priority order.

After setting the priority order, the power control device 1 is operated, and when the pulse input is detected by the pulse detector D (Yes in S11), the current power amount calculation unit 111a calculates the current power amount P (S12). After the calculation of the current power amount P or after the pulse input is detected, if there is no next pulse input (No in S11), it is determined whether or not there is a calculation timer interrupt (S13). When there is an interruption (Yes in S13), the predicted power amount calculation unit 111b calculates the predicted power amount R (S14), and the adjustment power amount calculation unit 111c calculates the adjusted power amount U (S15).

  Here, the calculation timer interruption means an operation of a timer for performing the calculation every 10 seconds, for example, as described with reference to FIGS.

After the calculation of S14 and S15, or when there is no operation timer interruption (No in S13), the signal generator 112 generates a control signal corresponding to the remaining time of the demand time period currently in progress (S16), The control signal generated in 13 is transmitted in accordance with a predetermined priority (S17). The generation and transmission of the control signal is as described with reference to FIG. Further, the transmission priority is as described above.

The control unit 13 that has received the control signal (S18) stops the connected compressor C by operating a relay circuit from the command unit 134 (S19). The stopped compressor C controls the restart of the compressor C according to the mode set by the first restart setting unit 116 (S20).

Hereinafter, with reference to FIG. 10, the power control processing step by the power control apparatus 1 in the case of the main switching contract will be described. The setting of the priority order is the same as in the case of the demand contract, and the description is omitted.

When the detection unit 121 of the low-voltage power side output unit 12 receives an alarm signal from the electronic breaker B, it determines whether or not an overcurrent condition is present (S22). Specifically, as described above, the determination is made based on the current capacity and the overcurrent determination condition. If it is provided (Yes in S22), the conversion unit 122a performs signal conversion processing for conversion to the control signal of the compressor C (S23), and transmits the control signal converted to the control unit 13 according to the set priority order. (S24). When the control signal is received by the control unit 13 (S25), the connected compressor C is stopped by operating the relay circuit from the command unit 134 (S26).

After the compressor C is stopped or when the overcurrent condition is not satisfied (No in S22), it is determined whether or not there is waiting for re-operation (S27). If it is not waiting for re-operation, a loop for determining whether or not an overcurrent condition is present is executed again (No in S27). On the other hand, when waiting for reactivation (Yes in S27), the compressor C is reactivated according to the mode set by the second reactivation setting unit 124 (S28).

DESCRIPTION OF SYMBOLS 1 Electric power control apparatus 11 High voltage electric power side output part 12 Low voltage electric power side output part 13 Control part 111 Detection part (High voltage electric power side output part)
111a Current power amount calculation unit 111b Predicted power amount calculation unit 111c Adjustment power amount calculation unit 112 Signal generation unit (high voltage power side output unit)
113 Synchronization processing unit 114 Display unit (High-voltage power side output unit)
115 alarm unit 116 first reactivation setting unit 121 detection unit (low voltage power side output unit)
121a Second switching unit 122 Signal generation unit (low voltage power side output unit)
123 Display (Low-voltage power output unit)
124 Second re-operation setting unit 131 First switching unit 132 Reception unit 133 Monitoring unit 134 Command unit 135 Protection unit E Electric energy meter D Pulse detector S Distribution board B Electronic breaker C Compressor

Claims (7)

A power control device that controls stop or restart of a plurality of compressors to be supplied with power according to a predetermined power contract,
Monitoring means for confirming the operating state of each compressor;
Detecting means for detecting the necessity of control from a preset threshold value based on a total of power consumption or current value permitted by the power contract for all of the plurality of compressors confirmed to be operating; ,
A signal generation means for generating a control signal for stopping or restarting each compressor according to the detected information, and transmitting the control signal to the compressor to be stopped or restarted;
Receiving means for sequentially receiving the control signal on each compressor side by a predetermined priority set in each compressor;
Command means for stopping or restarting the compressor specified by the received control signal;
Protective means for preventing restart or stop of the compressor within a predetermined time after the stop or restart is executed,
The signal generation means includes a first switching means that allows the reception means to selectively receive each control signal generated corresponding to the received voltage specified by the type of the power contract. A power control device.   The type of the power contract is at least a predetermined high-voltage contract power, a high-voltage power reception contract that determines the cost by the power used in a predetermined time unit, and a predetermined low-voltage contract power, and the main switch to be installed is the maximum 2. The power control apparatus according to claim 1, wherein the power control apparatus is of two types: a low-voltage power reception contract that calculates contract power based on a capacity capable of limiting current. In the case where the first switching unit has selected to be able to receive a control signal corresponding to the high-voltage power receiving contract, the detection unit obtains a pulse signal from a watt hour meter via a pulse detector. Current power amount calculation means for calculating the amount of power used within the time period set in the predetermined time unit from the acquired pulse signal, and the time limit when the current load state continues based on the calculated current power amount Based on the predicted power amount calculation means at the end time and the calculated predicted power amount, the amount of power necessary for stopping or resuming to reach the target power amount at the end of the time limit arbitrarily set in advance is calculated. Adjusting electric energy calculation means for calculating,
The signal generation means is an adjustment limit value that sets the total power consumption of the plurality of compressors as adjustable power when the predicted power amount exceeds or exceeds the target power amount. 3. The power control apparatus according to claim 2, wherein in the case described above, the control signal for stopping the compressor is generated according to the priority order during a predetermined elapsed time within the time limit.   Regarding the generation and transmission timing of the reactivation control signal, a mode for generating and transmitting under a predetermined condition within the same time period when the stop control signal is transmitted, and a time period after transmitting the stop control signal. A mode for generating and transmitting a control signal for restart at the start of an incoming time period, and the order of generation and transmission of the control signal for restart is the highest priority order. 4. The power according to claim 3, further comprising: a first restart setting unit configured to be able to set one of a mode for generating and transmitting in a mode and a mode for generating and transmitting in the order of low priority. Control device.   When the first switching unit selects the control signal corresponding to the low-voltage power reception contract to be received, and the detection unit acquires an alarm signal set in the main switch, the signal generation 3. The power control apparatus according to claim 2, wherein the means includes conversion means for converting into the control signal in accordance with a predetermined detection current capacity and an overcurrent determination condition.   6. The power control apparatus according to claim 2, further comprising second switching means that can selectively receive the alarm signals of a plurality of different main switches.   About the order of generation and transmission of the reactivation control signal, it is possible to set one of a mode for generating and transmitting in the order of higher priority and a mode of generating and transmitting in the order of lower priority The power control apparatus according to claim 5, further comprising a second restart setting unit configured to perform the second restart setting unit.

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