Electronic circuit breaker and circuit breaker system

Abstract

The electronic circuit breaker (1) comprises a load current characteristic calculation unit (17) and an output unit (20). The load current characteristic calculation unit (17) calculates the current characteristic of the load in the short-time region, i.e., the short-time load current characteristic, based on the peak value calculated by the peak value calculation unit (12), and calculates the current characteristic of the load in the long-time region, i.e., the long-time load current characteristic, based on the effective value calculated by the effective value calculation unit (13). The output unit (20) outputs information on the load current characteristic including the short-time load current characteristic and the long-time load current characteristic calculated by the load current characteristic calculation unit (17).

Description

Technical Field

[0001] The present invention relates to an electronic circuit breaker and a circuit breaker system. Background Art

[0002] Conventionally, in electronic circuit breakers equipped with microcomputers, the overcurrent tripping action characteristics can be changed. Therefore, if a load device is added or the operation mode of the load device is changed after the electronic circuit breaker is installed, the overcurrent tripping action characteristics can be changed, so that the installed electronic circuit breaker can continue to be used without replacing it.

[0003] The operator who sets the overcurrent tripping action characteristic roughly calculates the current flowing through the load, i.e., the load current, based on the product specifications of the full load devices that constitute the load connected to the electronic circuit breaker, and sets the overcurrent tripping action characteristic with a slightly larger margin than the load current.

[0004] However, in the above operation, it takes time to roughly calculate the load current according to the product specifications of the load instrument, so a technology that makes it easy to set the overcurrent tripping action characteristic has been developed. For example, Patent Document 1 discloses an electronic circuit breaker that measures the maximum power-on duration relative to each load current value, and calculates a characteristic representing the relationship between the load current value and the maximum power-on duration based on the measured result as a maximum load time-limiting characteristic. The electronic circuit breaker displays characteristic information including the maximum load time-limiting characteristic and the overcurrent tripping action characteristic on a display unit, and can change the overcurrent tripping action characteristic. As a result, in the electronic circuit breaker described in Patent Document 1, it is possible to easily set the overcurrent tripping action characteristic.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-93946 Summary of the invention

[0006] However, in the electronic circuit breaker described in Patent Document 1, overcurrent is detected using a current integrated value obtained by integrating the current product obtained by multiplying the load current effective value by the sampling period. Therefore, in the electronic circuit breaker described in Patent Document 1, for example, when the load is a generator, when the starting current of the generator flows and a short-time overcurrent is detected and the circuit is disconnected, the maximum load time characteristic may not exceed the value specified by the short-time operation characteristic among the overcurrent trip operation characteristics, and the overcurrent trip operation characteristics cannot be properly performed.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to obtain an electronic circuit breaker with which a user can appropriately perform overcurrent tripping operation characteristics.

[0008] In order to solve the above-mentioned problems and achieve the purpose, the electronic circuit breaker of the present invention has an opening and closing contact, a tripping device, a current detection unit, a peak value calculation unit, an effective value calculation unit, a short-time tripping processing unit, a long-time tripping processing unit, a load current characteristic calculation unit and an output unit. The opening and closing contacts open and close the circuit between the power supply and the load. The tripping device sets the opening and closing contacts to an open circuit state from a closed state. The current detection unit detects the current flowing in the circuit. The peak value calculation unit calculates the peak value of the current detected by the current detection unit. The effective value calculation unit calculates the effective value of the current detected by the current detection unit. When the short-time tripping processing unit determines that an overcurrent is flowing in the circuit in the short-time area based on the peak value calculated by the peak value calculation unit, the tripping device sets the opening and closing contacts to an open circuit state from a closed state. The long-time trip processing unit causes the trip device to change the switch contact from a closed state to an open state when it is determined based on the effective value calculated by the effective value calculation unit that an overcurrent flows in the circuit in a region of a long time limit that is longer than the short time limit. The load current characteristic calculation unit calculates the current characteristic of the load in the region of the short time limit, i.e., the short-time load current characteristic, based on the peak value calculated by the peak value calculation unit, and calculates the current characteristic of the load in the region of the long time limit, i.e., the long-time load current characteristic, based on the effective value calculated by the effective value calculation unit. The output unit outputs information on the load current characteristic including the short-time load current characteristic and the long-time load current characteristic calculated by the load current characteristic calculation unit.

[0009] Effects of the Invention

[0010] According to the present invention, there is an effect that a user can appropriately perform overcurrent trip operation characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a diagram showing a configuration example of a circuit breaker system according to Embodiment 1 of the present invention.

[0012] Figure 2 It is a diagram showing the overcurrent tripping operation characteristics and the advance warning operation characteristics according to the first embodiment.

[0013] Figure 3 This is a diagram showing an example of the configuration of an information processing device according to Embodiment 1.

[0014] Figure 4 This is a diagram showing an example of characteristic information displayed by the information processing device according to the first embodiment.

[0015] Figure 5 This is a diagram showing another example of the characteristic information displayed by the information processing device according to the first embodiment.

[0016] Figure 6 This is a flowchart showing an example of processing performed by the processing unit of the electronic circuit breaker according to the first embodiment.

[0017] Figure 7 This is a diagram showing an example of the overcurrent tripping operation characteristics of the electronic circuit breaker according to the first embodiment.

[0018] Figure 8 This is a flowchart showing an example of short time limit counter processing performed by the processing unit of the electronic circuit breaker according to the first embodiment.

[0019] Fig. 9 This is a flowchart showing an example of a load current characteristic calculation process performed by the processing unit of the electronic circuit breaker according to the first embodiment.

[0020] Fig.10 This is a flowchart showing an example of TxP update processing performed by the processing unit of the electronic circuit breaker according to the first embodiment.

[0021] Fig.11 This is a diagram showing an example of a load current when the load according to the first embodiment is a generator.

[0022] Fig.12 It is used for Fig.11 The figure is used to explain the TxP update process of the first cycle.

[0023] Fig.13 It is used for Fig.11 The figure illustrates the TxP update process of the second cycle.

[0024] Fig.14 It is used for Fig.11 The figure illustrates the TxP update process of the third cycle.

[0025] Fig.15 It is used for Fig.11 The figure illustrates the TxP update process of the 4th cycle.

[0026] Fig.16 It is used for Fig.11 The figure shows the TxP update process of the 5th cycle.

[0027] Fig.17 It is used for Fig.11The figure shows the TxP update process of the 6th cycle.

[0028] Fig.18 It is used for Fig.11 The figure shows the TxP update process of the 7th cycle.

[0029] Fig.19 It is used for Fig.11 The figure shows the TxP update process of the 99th cycle.

[0030] Fig. 20 It is used for Fig.11 The figure illustrates the TxS update processing of the first cycle and the second cycle.

[0031] Fig.21 It is used for Fig.11 The figure illustrates the TxS update processing of the 3rd and 4th cycles shown.

[0032] Fig. 22 It is used for Fig.11 The figure shows the TxS update process of the 5th and 6th cycles.

[0033] Fig.23 It is used for Fig.11 The figure shows the TxS update processing of the 7th cycle and the 99th cycle.

[0034] Fig.24 This is a diagram showing an example of a hardware configuration of a processing unit of the electronic circuit breaker according to the first embodiment. DETAILED DESCRIPTION

[0035] Hereinafter, an electronic circuit breaker and a circuit breaker system according to an embodiment of the present invention will be described in detail with reference to the drawings. In addition, the present invention is not limited to the present embodiment.

[0036] Implementation method 1.

[0037] Figure 1 FIG. 1 is a diagram showing a configuration example of a circuit breaker system according to Embodiment 1 of the present invention. Figure 1 As shown, the circuit breaker system 100 according to the first embodiment includes an electronic circuit breaker 1 and an information processing device 50. The information processing device 50 is a mobile device such as a smartphone, a tablet or a portable computer. The electronic circuit breaker 1 and the information processing device 50 are connected to each other so as to be able to communicate with each other through short-range wireless communication such as Bluetooth (registered trademark).

[0038] The electronic circuit breaker 1 connects and disconnects a 3-phase 3-wire circuit 6 connecting a power source 2 and a load 3. The circuit 6 connecting the power source 2 and the load 3 is not limited to a 3-phase 3-wire circuit, and may be, for example, a single-phase 2-wire circuit, a single-phase 3-wire circuit, or a 3-phase 4-wire circuit. Figure 1 In the example shown, the load 3 includes an electrical instrument 31 and an electrical device 32, but the load 3 is not limited to Figure 1 Example shown.

[0039] The electronic circuit breaker 1 includes: a switch contact 4 for opening and closing a circuit 6; a trip device 5 for changing the switch contact 4 from a closed state to an open state; and a current detection unit 7 for detecting a load current, that is, a current flowing through the load 3 via the circuit 6. The switch contact 4 includes switch contacts 41 to 43 for opening and closing corresponding circuits among three circuits 61 to 63 constituting the circuit 6.

[0040] Each of the switch contacts 41 to 43 has a fixed contact (not shown) and a movable contact (not shown). At each of the switch contacts 41 to 43, the movable contact contacts and the fixed contact contacts are in contact and the state is closed, and the power supply 2 and the load 3 provided in the electronic circuit breaker 1 are electrically connected. As a result, current flows in each of the circuits 61 to 63, and the electronic circuit breaker 1 is in the on state.

[0041] Furthermore, at each of the switching contacts 41 to 43, the movable contact separates from the fixed contact, and the switching contact 4 changes from the closed state to the open state, and the power supply 2 and the load 3 are electrically disconnected. Thus, the current of each circuit 61 to 63 is interrupted, and the electronic circuit breaker 1 is in the open state.

[0042] The current detection unit 7 includes: a plurality of current transformers 81, 82, 83, which respectively output analog current signals proportional to the instantaneous values ​​of the load currents flowing in the corresponding circuits among the circuits 61, 62, 63; and a voltage conversion unit 9, which converts the plurality of analog current signals output from the current transformers 81, 82, 83 into a plurality of analog voltage signals.

[0043] In addition, the electronic circuit breaker 1 includes a processing unit 10, a trip circuit 30, an input unit 31, and a notification unit 32. The processing unit 10 has information on overcurrent detection characteristics, that is, overcurrent trip operation characteristics, and determines whether the load current detected by the current detection unit 7 is an overcurrent based on the overcurrent trip operation characteristics. When the processing unit 10 determines that the load current is an overcurrent, it outputs a trip signal S to the trip circuit 30.

[0044] The trip circuit 30 drives the trip device 5 to perform a tripping action when, for example, the trip signal S is output from the processing unit 10. The tripping action is an action of changing the switch contact 4 from a closed state to an open state. The input unit 31 includes a plurality of dials for setting information on overcurrent tripping action characteristics and pre-alarm action characteristics, and a measurement start button for causing the processing unit 10 to calculate a load current time characteristic described later. The notification unit 32 includes, for example, any one of a speaker, a lamp, or a display unit, and performs a pre-alarm by sound, light, or image based on a request from the processing unit 10.

[0045] The processing unit 10 has information on the pre-alarm operation characteristics and determines whether the load current detected by the current detection unit 7 is in a state requiring a pre-alarm based on the pre-alarm operation characteristics. The processing unit 10 outputs a pre-alarm if it determines that the load current is in a state requiring a pre-alarm.

[0046] Here, the overcurrent tripping operation characteristics and the advance warning operation characteristics are explained. Figure 2 1 is a diagram showing the overcurrent tripping operation characteristics and the pre-alarm operation characteristics involved in the first embodiment. Figure 2 In the figure, the horizontal axis represents the load current and the vertical axis represents the operation time.

[0047] The overcurrent tripping action characteristic is a characteristic that indicates the relationship between the overcurrent determination threshold used in determining whether an overcurrent is flowing and the tripping action time. The overcurrent tripping action characteristic of the electronic circuit breaker 1 includes an instantaneous tripping characteristic, a short-limit tripping characteristic, and a long-limit tripping characteristic. The instantaneous tripping characteristic specifies the overcurrent determination threshold for the tripping action, i.e., the instantaneous tripping action, in the instantaneous tripping area. The short-limit tripping characteristic specifies the overcurrent determination threshold for the tripping action, i.e., the short-limit tripping action, in the short-limit tripping area. The long-limit tripping characteristic specifies the overcurrent determination threshold for the tripping action, i.e., the long-limit tripping action, in the long-limit tripping area. In addition, the short-limit tripping area is sometimes recorded as the short-limit area, and the long-limit tripping area is sometimes recorded as the long-limit area.

[0048] The pre-alarm operation characteristic is a characteristic indicating the relationship between the pre-alarm threshold value smaller than the overcurrent determination threshold value and the pre-alarm operation time, and when a current for which an alarm should be issued flows through the circuit 6, an alarm is output from the electronic circuit breaker 1. This alarm is issued before an overcurrent flows in the circuit 6, and is therefore called a pre-alarm.

[0049] exist Figure 2In addition to the overcurrent tripping action characteristic and the pre-alarm action characteristic, the maximum load current time characteristic is also shown. The maximum load current time characteristic is a load current time characteristic obtained by measuring the load current value during the period when the load current becomes maximum, and shows the relationship between each load current value and the maximum power-on time. The load current time characteristic is a characteristic that shows the relationship between each load current value and the power-on time. The power-on time is the time compared with the action time in the overcurrent tripping action characteristic. When the power-on time exceeds the action time specified by the overcurrent tripping action characteristic, a tripping action is performed in the electronic circuit breaker 1.

[0050] Back to Figure 1 Next, the processing unit 10 of the electronic circuit breaker 1 is described. The processing unit 10 includes an AD (Analog-to-Digital) conversion unit 11, a peak value calculation unit 12, an effective value calculation unit 13, an instantaneous trip processing unit 14, a short-time limit trip processing unit 15, a long-time limit trip processing unit 16, a load current characteristic calculation unit 17, a pre-alarm processing unit 18, a recommended value calculation unit 19, an output unit 20, a communication unit 21, a setting unit 22, and a storage unit 23.

[0051] The AD converter 11 converts each of the plurality of analog voltage signals output from the current detection unit 7 into a digital signal for each preset period T1. The digital signal includes a digital value representing the instantaneous value of the load current. The period T1 is, for example, 1 [ms]. The AD converter 11 outputs the converted plurality of digital signals to the peak value calculation unit 12, the effective value calculation unit 13, and the instantaneous trip processing unit 14.

[0052] The peak value calculation unit 12 detects the load current peak value Ipeak which is the peak value of the load current flowing through the electric circuit 6 for each preset period T2 based on a plurality of digital signals output from the AD conversion unit 11. The period T2 is, for example, 20 [ms].

[0053] The peak value calculation unit 12 calculates the maximum value of the instantaneous value of the load current in the preset period T3 as the peak value, i.e., the load current peak value Ipeak, based on the multiple digital signals output from the AD conversion unit 11. The period T3 is, for example, 20 [msec] when the frequency of the AC voltage output from the power supply 2 is 50 [Hz].

[0054] In addition, the effective value calculation unit 13 calculates the load current effective value Irms, which is the effective value of the load current flowing through the circuit 6, based on the plurality of digital signals output from the AD conversion unit 11 for each period T2. For example, the effective value calculation unit 13 obtains a moving average of values ​​obtained by squaring the instantaneous value of the load current included in the digital signal output from the AD conversion unit 11, and calculates the square root of the result of the moving average, thereby being able to obtain the load current effective value Irms.

[0055] The instantaneous trip processing unit 14 determines whether the instantaneous value of the load current flowing through the circuit 6 exceeds the overcurrent determination threshold value specified by the instantaneous trip operation characteristic for each period T1 based on the plurality of digital signals output from the AD conversion unit 11. When the instantaneous trip processing unit 14 determines that the instantaneous value of the load current flowing through the circuit 6 exceeds the overcurrent determination threshold value, the output unit 20 outputs a trip signal S to the trip circuit 30.

[0056] The short time limit trip processing unit 15 determines whether an overcurrent flows in the short time limit region in the circuit 6 based on the load current peak value Ipeak. Specifically, the short time limit trip processing unit 15 outputs a trip signal S from the output unit 20 to the trip circuit 30 when the load current peak value Ipeak exceeds the overcurrent determination threshold value specified by the short time limit trip characteristic for each period T2.

[0057] The long-time trip processing unit 16 determines whether an overcurrent flows in the long-time region of the circuit 6 based on the load current effective value Irms. Specifically, the long-time trip processing unit 16 outputs a trip signal S from the output unit 20 to the trip circuit 30 when the load current effective value Irms exceeds the overcurrent determination threshold value specified by the long-time trip characteristic for each period T2. In addition, the long-time trip processing unit 16 can also determine whether an overcurrent flows in the long-time region of the circuit 6 based on the load current effective value Irms and the load current peak value Ipeak.

[0058] The load current characteristic calculation unit 17 calculates the load current time characteristic indicating the relationship between the load current and the energization time. The load current characteristic calculation unit 17 measures the load current value during the period when the load current is maximum, thereby being able to calculate the maximum load current time characteristic indicating the relationship between the load current and the maximum energization time.

[0059] Based on the load current peak value Ipeak, the load current time characteristic in the short-time region, i.e., the short-time load current characteristic, is calculated. In addition, the load current characteristic calculation unit 17 calculates the load current time characteristic in the long-time region, i.e., the long-time load current characteristic, based on the load current effective value Irms. The short-time load current characteristic is a characteristic indicating the relationship between the load current and the power-on time in the short-time region, and the long-time load current characteristic is a characteristic indicating the relationship between the load current and the power-on time in the long-time region.

[0060] As described above, the load current characteristic calculation unit 17 calculates the short-time load current characteristic based on the load current peak value Ipeak used for trip determination in the short-time trip processing unit 15, and calculates the long-time load current characteristic using the load current effective value Irms used for trip determination in the long-time trip processing unit 16. Thus, the electronic circuit breaker 1 can present the load current time characteristic that matches the overcurrent trip operation characteristic to the user, so that the user can appropriately adjust the overcurrent trip operation characteristic.

[0061] The load current characteristic calculation unit 17 calculates the long-time load current characteristic and the short-time load current characteristic when the user operates the measurement start button of the input unit 31. The user can operate the measurement start button at the start timing of the period when the load current becomes the maximum state, so that the load current characteristic calculation unit 17 calculates the maximum load current time characteristic. The load current characteristic calculation unit 17 associates the information of the calculated load current time characteristic with the information of the measurement period and stores it in the storage unit 23. In addition, the storage unit 23 stores the information of the overcurrent tripping action characteristic and the information of the advance warning action characteristic in addition to the information of the load current time characteristic.

[0062] The pre-alarm processing unit 18 determines whether to output the pre-alarm to the notification unit 32 based on the load current effective value Irms. The pre-alarm processing unit 18 has information on the pre-alarm action characteristics. Specifically, the pre-alarm processing unit 18 determines whether the load current effective value Irms exceeds the pre-alarm threshold value specified by the pre-alarm action characteristics. If the pre-alarm processing unit 18 determines that the load current effective value Irms exceeds the pre-alarm current threshold value Ip, the pre-alarm processing unit 18 outputs the pre-alarm to the notification unit 32.

[0063] The recommended value calculation unit 19 calculates the recommended value of the pre-alarm operation characteristic based on the information of the load current time characteristic and the information of the overcurrent tripping operation characteristic. For example, the recommended value calculation unit 19 calculates the recommended value of the pre-alarm operation characteristic in a manner that is an intermediate characteristic between the load current time characteristic and the overcurrent tripping operation characteristic. The recommended value calculation unit 19 stores the calculated recommended value of the pre-alarm operation characteristic in the storage unit 23. In addition, the electronic circuit breaker 1 may also be configured not to include the recommended value calculation unit 19.

[0064] The output unit 20 outputs the trip signal S to the trip circuit 30 based on the request from the instantaneous trip processing unit 14, the short-time limit trip processing unit 15, and the long-time limit trip processing unit 16. The communication unit 21 performs short-range wireless communication such as Bluetooth to communicate with the information processing device 50. For example, when the communication unit 21 receives a request for sending characteristic information, that is, an information sending request from the information processing device 50, the characteristic information representing the overcurrent tripping action characteristic, the advance alarm action characteristic, and the load current time limit characteristic stored in the storage unit 23 is sent to the information processing device 50.

[0065] The setting unit 22 can set the information of the overcurrent tripping action characteristics and the information of the pre-alarm action characteristics based on the operation of the user to the input unit 31 or the information output from the communication unit 21. For example, the setting unit 22 sets the new information of the overcurrent tripping action characteristics in the short-time limit tripping processing unit 15 and the long-time limit tripping processing unit 16 based on the operation of the user to the input unit 31 or the information output from the communication unit 21, and stores the new information of the overcurrent tripping action characteristics in the storage unit 23. In addition, the setting unit 22 sets the new information of the pre-alarm action characteristics in the pre-alarm processing unit 18 based on the operation of the user to the input unit 31 or the information output from the communication unit 21, and stores the new information of the pre-alarm action characteristics in the storage unit 23.

[0066] Upon receiving the characteristic information from the electronic circuit breaker 1 , the information processing device 50 displays the received characteristic information. Figure 3 This is a diagram showing an example of the configuration of an information processing device according to Embodiment 1. Figure 4 This is a diagram showing an example of characteristic information displayed by the information processing device according to the first embodiment. Figure 5 This is a diagram showing another example of the characteristic information displayed by the information processing device according to the first embodiment.

[0067] like Figure 3As shown, the information processing device 50 includes a communication unit 51, a display unit 52, an input unit 53, a control unit 54, and a storage unit 55. The communication unit 51 performs short-range wireless communication such as Bluetooth to communicate with the electronic circuit breaker 1. The display unit 52 is, for example, an LCD (Liquid Crystal Display) or an organic EL (ElectroLuminescence) display. The input unit 53 includes, for example, a keyboard, a mouse, an auxiliary keyboard, or a touch panel.

[0068] The control unit 54 causes the communication unit 51 to transmit a request for transmitting characteristic information, i.e., an information transmission request, to the electronic circuit breaker 1 based on a user operation on the input unit 53. The control unit 54 obtains the characteristic information transmitted from the electronic circuit breaker 1 in response to the information transmission request and received by the communication unit 51 from the communication unit 51, and causes the storage unit 55 to store the obtained characteristic information. The control unit 54 obtains the characteristic information from the storage unit 55 based on a user operation on the input unit 53, such as Figure 4 As shown, the acquired characteristic information is displayed on the display unit 52.

[0069] The control unit 54 also includes a display processing unit 60, a setting processing unit 61, and a recommended value calculation unit 62. The display processing unit 60 acquires information for generating characteristic information and an update image from the storage unit 55, and can cause the display unit 52 to display the update image based on the acquired information.

[0070] like Figure 5 As shown, the update image 70 displayed on the display unit 52 of the information processing device 50 includes a characteristic display area 71, a current setting value display area 72 indicating the current setting value, and a box display area 73 for inputting a new setting value. The update image 70 includes a setting value change bar 74, an acquisition button 75, a recommended value calculation button 76, a recommended value setting button 77, an update button 78, and a write button 79.

[0071] The graphs showing the overcurrent tripping action characteristics, the pre-alarm action characteristics and the load current time limit characteristics are arranged in the characteristic display area 71. The current setting values ​​of each characteristic, i.e., "Iu", "TL", "Is", "Ts", "Ii" and "Ip", are shown in the current setting value display area 72. "Iu" is the continuous current value, which is set within the range of 0.8 to 1.0 times the rated current In, for example.

[0072] "TL" is the long time limit tripping operation time that specifies the operation time in the long time limit tripping area. Figure 5The "Is" shown is the overcurrent judgment threshold in the short-time tripping area, i.e., the short-time operating current threshold, which is set, for example, in the range of 1.5 to 10 times the rated current In. "Ts" is the short-time tripping operating time that specifies the operating time in the short-time tripping area. "Ii" is the overcurrent judgment threshold in the instantaneous tripping area. "Ip" is the pre-alarm current threshold.

[0073] The frame display area 73 includes a text box in which a new setting value of each characteristic can be input, and the user of the information processing device 50 can input a new setting value into each text box by operating the input unit 53 .

[0074] The setting value change bar 74 is a GUI (Graphical User Interface) for changing the setting of a characteristic selected by operating the input unit 53 among the plurality of characteristics. The user of the information processing device 50 can change the setting value by operating the setting value change bar 74 by operating the input unit 53.

[0075] The acquisition button 75 is a GUI button for acquiring information on the load current time characteristics from the electronic circuit breaker 1. By operating the acquisition button 75, the user transmits a load characteristic transmission request for requesting information on the load current time characteristics to the electronic circuit breaker 1, and acquires the load current time characteristics information transmitted from the electronic circuit breaker 1 in response to the load characteristic transmission request.

[0076] The recommended value calculation button 76 is a GUI button for calculating the recommended value of the pre-alarm action characteristic. When the recommended value calculation button 76 is operated by the user, the recommended value calculation unit 62 of the control unit 54 calculates the recommended value of the pre-alarm action characteristic based on the information of the load current time characteristic and the information of the overcurrent tripping action characteristic. For example, the recommended value calculation unit 62 calculates the recommended value of the pre-alarm action characteristic in a manner that is an intermediate characteristic between the load current time characteristic and the overcurrent tripping action characteristic. Moreover, the display processing unit 60 configures the recommended pre-alarm action characteristic in the characteristic display area 71 based on the recommended value of the pre-alarm action characteristic calculated by the recommended value calculation unit 62. In addition, the display processing unit 60 can also input the recommended value of the pre-alarm action characteristic calculated by the recommended value calculation unit 62 into the text box of the box display area 73.

[0077] In addition, the information processing device 50 may be configured without the recommended value calculation unit 62. In this case, the control unit 54 of the information processing device 50 sends a recommended value calculation request to the electronic circuit breaker 1, so that the recommended value calculation unit 19 of the electronic circuit breaker 1 can calculate the recommended value of the pre-alarm operation characteristic. The recommended value calculation unit 19 sends the information of the recommended value of the pre-alarm operation characteristic to the information processing device 50 via the communication unit 21. The control unit 54 of the information processing device 50 obtains the information of the recommended value of the pre-alarm operation characteristic via the communication unit 51. The display processing unit 60 arranges the recommended pre-alarm operation characteristic in the characteristic display area 71 based on the recommended value of the pre-alarm operation characteristic calculated by the electronic circuit breaker 1. In addition, the display processing unit 60 can also input the recommended value of the pre-alarm operation characteristic calculated by the electronic circuit breaker 1 into the text box of the box display area 73.

[0078] The recommended value setting button 77 is a GUI button for setting the recommended value of the pre-alarm operation characteristic as a new setting value of the pre-alarm operation characteristic in the electronic circuit breaker 1. When the recommended value setting button 77 is operated by the user, the recommended value calculation unit 62 of the control unit 54 calculates the recommended value of the pre-alarm operation characteristic. Then, the setting processing unit 61 of the control unit 54 causes the communication unit 51 to transmit the setting request information including the recommended value of the pre-alarm operation characteristic to the electronic circuit breaker 1 as a new setting value of the pre-alarm operation characteristic. The setting unit 22 of the electronic circuit breaker 1 obtains the setting request information via the communication unit 21, and sets the recommended value of the pre-alarm operation characteristic included in the obtained setting request information as a new setting value of the pre-alarm operation characteristic in the pre-alarm processing unit 18.

[0079] The update button 78 is a GUI button for inputting a value corresponding to the position of the set value change bar 74 into the text box of the frame display area 73. When the update button 78 is operated by the user, the display processing unit 60 of the control unit 54 inputs the value corresponding to the position of the set value change bar 74 into the text box of the frame display area 73.

[0080] The write button 79 is a GUI button for setting the new setting value input to the text box of the frame display area 73 to the electronic circuit breaker 1. When the user operates the write button 79, the setting processing unit 61 of the control unit 54 causes the communication unit 51 to transmit setting request information including the new setting value input to the text box of the frame display area 73 to the electronic circuit breaker 1. The setting unit 22 of the electronic circuit breaker 1 obtains the setting request information via the communication unit 21, and sets the information included in the obtained setting request information to the short-time limit trip processing unit 15, the long-time limit trip processing unit 16, and the advance warning processing unit 18.

[0081] Next, the processing performed by the processing unit 10 of the electronic circuit breaker 1 will be described using a flowchart. Figure 6 This is a flowchart showing an example of processing performed by the processing unit of the electronic circuit breaker according to the first embodiment, and the processing is repeatedly executed for each processing routine time ΔTroop.

[0082] like Figure 6 As shown, the processing unit 10 sets the power-on time data Tx to 0 and performs initialization (step S10). The power-on time data Tx includes data of the power-on time TxP[i] and data of the power-on time TxS[i] for each current level Ilevel[i]. "i" is an arbitrary integer from "1" to "n", and the power-on time data Tx includes data of the power-on time TxP[1] to TxP[n] and data of the power-on time TxS[1] to TxS[n] for current levels Ilevel[1] to [n].

[0083] n is the maximum value of the current level Ilevel. The maximum value of the current level Ilevel is Figure 2 The value obtained by dividing the maximum value of the horizontal axis of the graph shown by the unit current value Imin. The unit current value Imin is Figure 2 The minimum unit of the value on the horizontal axis of the graph shown.

[0084] Next, the processing unit 10 calculates the load current effective value Irms based on the digital value output from the AD converter 11 (step S11). The processing unit 10 determines whether the load current effective value Irms calculated in step S11 exceeds the pre-warning current threshold value Ip (step S12).

[0085] When the processing unit 10 determines that the load current effective value Irms exceeds the pre-warning current threshold value Ip (step S12: Yes), it determines whether the load current effective value Irms calculated in step S11 exceeds the short-time action current threshold value Is (step S13). When the processing unit 10 determines that the load current effective value Irms exceeds the short-time action current threshold value Is (step S13: Yes), the processing routine time ΔTroop is multiplied by the square value Is of the short-time action current threshold value Is relative to the current accumulated current value S1. 2 The obtained current product is added to the previous integrated current value S2, and then, in order to perform the next processing routine, the previous integrated current value S2 is set to the same value as the current integrated current value S1 (step S14).

[0086] Here, the current integrated current value S1 will be described. Figure 7FIG. 1 is a diagram showing an example of the overcurrent tripping operation characteristics of the electronic circuit breaker according to Embodiment 1. Figure 7 When the load current with the load current effective value Irms1 shown in FIG. 1 continues to flow during the time Te2, the current cumulative current value S1 is a line segment from 0 to Te2 on the vertical axis and from 0 to Irms1 on the horizontal axis. 2 The area of ​​the rectangle enclosed by the line segment to the left can be calculated by S1 = Te2 × Irms1 2 express.

[0087] exist Figure 6 In step S13 shown in FIG. 1 , when the processing unit 10 determines that the load current effective value Irms does not exceed the short-time operating current threshold value Is (step S13: No), the overcurrent excess flag Flg is set to "1" (step S15). Furthermore, the processing unit 10 multiplies the processing routine time ΔTroop by the square value Irms of the load current effective value Irms with respect to the current accumulated current value S1. 2 The obtained current product is added to the previous integrated current value S2, and then, in order to perform the next processing routine, the previous integrated current value S2 is set to the same value as the current integrated current value S1 (step S16).

[0088] When the processing unit 10 determines that the load current effective value Irms does not exceed the pre-warning current threshold value Ip (step S12: No), it determines whether the overcurrent excess flag Flg is "1" (step S18). When the processing unit 10 determines that the overcurrent excess flag Flg is "1" (step S18: Yes), it jumps to the residual current product correction process in step S19.

[0089] Specifically, the processing unit 10 subtracts the current product obtained by multiplying the processing routine time ΔTroop by the heat dissipation coefficient P from the previous cumulative current value S2 with respect to the current cumulative current value S1, and then sets the previous cumulative current value S2 to the same value as the current cumulative current value S1 in order to perform the next processing routine (step S19). By subtracting the current product obtained by multiplying the processing routine time ΔTroop by the heat dissipation coefficient P from the previous cumulative current value S2, when the load current effective value Irms is less than or equal to the pre-alarm current threshold value Ip, a value corresponding to cooling can be subtracted from the current cumulative current value S1. The heat dissipation coefficient P is a heat dissipation coefficient per unit time. The unit time is, for example, 1 second.

[0090] Next, the processing unit 10 determines whether the current accumulated current value S1 is less than "0" (step S20). When the processing unit 10 determines that the current accumulated current value S1 is less than "0" (step S20: Yes), the current accumulated current value S1 and the previous accumulated current value S2 are set to "0" (step S21), and the overcurrent excess flag Flg is set to "0" (step S22).

[0091] When the processing of step S14 is completed or when the processing of step S16 is completed, the processing unit 10 determines whether the current cumulative current value S1 is greater than or equal to a constant K (step S17). The constant K is an overcurrent determination threshold value specified by a preset long-time limit trip characteristic in the overcurrent trip operation area. The long-time limit trip characteristic is based on Figure 5 The value of "TL" shown in FIG. 1 is set according to the value of "TL". "TL" represents the long time limit tripping operation time when a load current twice the rated current In flows, for example.

[0092] exist Figure 7 In the long-time tripping characteristic, the long-time tripping action time Te1 is expressed as Te1 = K / Irms1 2 The constant K is equivalent to Figure 7 The area S0 is the value of the area S0 shown. The area S0 is the line segment from 0 to Te1 on the vertical axis and from 0 to Irms1 on the horizontal axis. 2 That is, the constant K is given by K = S0 = Te1 × Irms1 2 Represents the value.

[0093] When the processing unit 10 determines that the current accumulated current value S1 is not greater than or equal to the constant K (step S17: No), when it is determined that the overcurrent excess flag Flg is not "1" (step S18: No), when it is determined that the current accumulated current value S1 is not less than "0" (step S20: No), or when the processing of step S22 is completed, the short-time counter processing is performed (step S23). The short-time counter processing is Figure 8 The processing of steps S30 to S33 shown will be described in detail later.

[0094] Next, the processing unit 10 determines whether the current short-time limit counter STD1 is greater than or equal to a constant L (step S24). The constant L is a value specified by a preset short-time limit trip characteristic in the overcurrent tripping operation area. For example, the constant L is an overcurrent determination threshold value obtained by multiplying the short-time limit operation current threshold Is by the short-time limit operation time Ts.

[0095] When the short-time limit trip processing unit 15 determines that the current short-time limit counter STD1 is not greater than or equal to the constant L (step S24: No), the processing unit 10 performs a load current characteristic calculation process (step S25) and jumps to the process to step S11. Fig. 9 The processing of steps S40 to S44 shown will be described in detail later.

[0096] When the processing unit 10 determines that the current short-time counter STD1 is greater than or equal to the constant L (step S24: Yes), or when the processing unit 10 determines that the current accumulated current value S1 is greater than or equal to the constant K (step S17: Yes), the processing unit 10 outputs the trip signal S to the trip circuit 30, causing the trip device 5 to change the switch contact 4 from the closed state to the open state (step S26), and ends. Figure 6 Processing shown.

[0097] In addition, the processing of step S11 is performed by the effective value calculation unit 13 of the processing unit 10, and the processing of steps S12 to S22 is performed by the long-time limit trip processing unit 16 of the processing unit 10. In addition, the processing of steps S23 and S24 is performed by the peak value calculation unit 12 and the short-time limit trip processing unit 15 of the processing unit 10, and the processing of step S25 is performed by the load current characteristic calculation unit 17. In addition, the processing of step S26 is performed by the output unit 20 of the processing unit 10.

[0098] Figure 8 FIG. 1 is a flowchart showing an example of short time limit counter processing performed by the processing unit of the electronic circuit breaker according to Embodiment 1. Figure 8 As shown, the peak value calculation unit 12 of the processing unit 10 calculates the load current peak value Ipeak based on the digital value output from the AD conversion unit 11 (step S30).

[0099] Next, the short-time trip processing unit 15 of the processing unit 10 determines whether the load current peak value Ipeak calculated in step S30 exceeds the short-time action current threshold value Is (step S31). When the short-time trip processing unit 15 determines that the load current peak value Ipeak exceeds the short-time action current threshold value Is (step S31: Yes), the value obtained by adding "1" to the value of the previous short-time counter STD2 is set as the value of the current short-time counter STD1, and then the value of the previous short-time counter STD2 is set to the same value as the current short-time counter STD1 in order to perform the next processing routine (step S32).

[0100] In addition, when the short-time trip processing unit 15 determines that the load current peak value Ipeak does not exceed the short-time operating current threshold value Is (step S31: No), the value obtained by subtracting "1" from the value of the previous short-time counter STD2 is set as the value of the current short-time counter STD1, and then, in order to perform the next processing routine, the value of the previous short-time counter STD2 is set to the same value as the current short-time counter STD1 (step S33). When the processing of step S32 is completed, or when the processing of step S33 is completed, the processing unit 10 ends. Figure 8 Processing shown.

[0101] Fig. 9 FIG. 1 is a flowchart showing an example of a load current characteristic calculation process performed by a processing unit of the electronic circuit breaker according to Embodiment 1. Fig. 9 As shown, the load current characteristic calculation unit 17 of the processing unit 10 performs TxS update processing (step S40) in order to obtain the energization time TxS[i].

[0102] In step S40, the load current characteristic calculation unit 17 calculates the current level I1level by dividing the current cumulative current value S1 by the unit current value Imin. The load current characteristic calculation unit 17 obtains information on the current cumulative current value S1 from the long-time limit trip processing unit 16. In addition, the load current characteristic calculation unit 17 may also be configured to calculate the current cumulative current value S1 by the same calculation as the long-time limit trip processing unit 16.

[0103] Furthermore, the load current characteristic calculation unit 17 calculates the power-on time TxS[1] to TxS[I1level]. If the current level Ilevel less than or equal to the current current level I1level is set to "x", the load current characteristic calculation unit 17 calculates the power-on time TxS[x] by the operation of the following formula (1). "x" is an integer from "1" to "I1level" and represents the current level Ilevel.

[0104] TxS[x]=ΔTroop×S1 / (x×Imin) 2 ···(1)

[0105] Specifically, the load current characteristic calculation unit 17 divides the current accumulated current value S1 by the square of the value obtained by multiplying each of the multiple current levels Ilevel[1] to Ilevel[I1level] up to the current current level I1level by the unit current value Imin, thereby obtaining the value of the maximum current counters Icntm[1] to Icntm[I1level]. Furthermore, the load current characteristic calculation unit 17 multiplies the value of each maximum current counter Icntm[1] to Icntm[I1level] by the processing routine time ΔTroop, thereby calculating the power-on time TxS[1] to TxS[I1level].

[0106] The current cumulative current value S1 is calculated based on the load current effective value Irms. Therefore, the power-on time TxS matching the long time limit tripping area of ​​the overcurrent tripping action characteristic can be obtained through step S40. However, if the load current less than or equal to the pre-alarm current threshold Ip continues to flow, the current value S1 is calculated based on the load current effective value Irms. Figure 6 The processing of step S19 shown in the figure. Therefore, when the load current less than or equal to the pre-alarm current threshold value Ip continues to flow, the current cumulative current value S1 becomes "0", so the power-on time TxS[x] cannot be calculated. In addition, in the short-time tripping area and the instantaneous tripping area, the overcurrent tripping action is performed based on the load current peak value Ipeak, so the power-on time matching the short-time tripping area and the instantaneous tripping area in the tripping action characteristics cannot be obtained.

[0107] Therefore, the load current characteristic calculation unit 17 performs a TxP update process for obtaining the energization time TxP[x] using the load current peak value Ipeak (step S41). Fig.10 The processing of steps S50 to S56 shown will be described in detail later.

[0108] Next, the load current characteristic calculation unit 17 determines whether the value of the power-on time TxS[x] is greater than the value of the power-on time TxP[x] for each current level Ilevel[x] (step S42). For example, the load current characteristic calculation unit 17 determines whether the value of the power-on time TxS[1] is greater than the value of the power-on time TxP[1], and determines whether the value of the power-on time TxS[I1level] is greater than the value of the power-on time TxP[I1level].

[0109] When the load current characteristic calculation unit 17 determines that the value of the power-on time TxS[x] is greater than the value of the power-on time TxP[x] (step S42: Yes), the load current characteristic calculation unit 17 sets the value of the power-on time TxS[x] to the value of the maximum power-on time Txmax[x] (step S43). For example, when the value of the power-on time TxS[1] is greater than the value of the power-on time TxP[1], the load current characteristic calculation unit 17 sets the value of the power-on time TxS[1] to the value of the maximum power-on time Txmax[1]. In addition, when the value of the power-on time TxS[I1level] is greater than the value of the power-on time TxP[I1level], the load current characteristic calculation unit 17 sets the value of the power-on time TxS[I1level] to the value of the maximum power-on time Txmax[I1level].

[0110] In addition, when the load current characteristic calculation unit 17 determines that the value of the power-on time TxS[x] is not greater than the value of the power-on time TxP[x] (step S42: No), the load current characteristic calculation unit 17 sets the value of the power-on time TxP[x] to the maximum power-on time Txmax[x] (step S44). For example, when the value of the power-on time TxS[1] is not greater than the value of the power-on time TxP[1], the load current characteristic calculation unit 17 sets the value of the power-on time TxP[1] to the maximum power-on time Txmax[1]. In addition, when the value of the power-on time TxS[I1level] is not greater than the value of the power-on time TxP[I1level], the load current characteristic calculation unit 17 sets the value of the power-on time TxP[I1level] to the maximum power-on time Txmax[I1level].

[0111] As described above, the load current characteristic calculation unit 17 uses the larger value of the power-on time TxS[x] and the power-on time TxP[x]. Thus, for example, in a case where there is a period when the load current periodically changes and is less than or equal to the pre-alarm current threshold value Ip, the power-on time TxP[x] is used. Therefore, for example, from the perspective of being used as a reference when setting the pre-alarm operation characteristic, the load current time characteristic can be calculated more appropriately.

[0112] When the process of step S43 is completed, or when the process of step S44 is completed, the load current characteristic calculation unit 17 stores the maximum power-on time Txmax[x] in the storage unit 55, and updates the information of the load current time characteristic (step S45). Fig. 9 Processing shown.

[0113] The load current characteristic calculation unit 17 repeats the above-described processing, thereby allowing the storage unit 55 to store information on the load current time characteristic including information on the maximum energization time Txmax[n] at each current level Ilevel.

[0114] In addition, the load current characteristic calculation unit 17 can use the power-on time TxP[k] in the short-time tripping area, and can use only the power-on time TxS[p] in the long-time tripping area and the area where the time is longer than the long-time tripping area. In addition, "k" is the current level Ilevel corresponding to the short-time tripping area, and "p" is the current level corresponding to the long-time tripping area and the area where the time is longer than the long-time tripping area.

[0115] Fig.10 FIG. 1 is a flowchart showing an example of TxP update processing performed by the processing unit of the electronic circuit breaker according to Embodiment 1. Fig.10 As shown, the load current characteristic calculation unit 17 calculates Figure 8 The load current peak value Ipeak calculated in step S30 is divided by the unit current value Imin, thereby calculating the current level I1level (step S50).

[0116] For example, when the range of the horizontal axis in the load current characteristic is set to 0 to 2000% of the rated current In and the unit current value Imin is set to 5% In, the range of the current level I1level becomes 1 to 400. When the load current peak value Ipeak is 1000% In, the current level I1level becomes 1000% In / 5% In = 200. In addition, "5% In" means 5% of the rated current In, and "1000% In" means 1000% of the rated current In.

[0117] Next, the load current characteristic calculation unit 17 adds “1” to the value of the current counter Icnt[x] that is less than or equal to the current level I1level among the current counters Icnt[1] to Icnt[n] (step S51 ). Fig.10 The "x" shown in step S51 is an integer from "1" to "I1level". Therefore, in the process of step S51, "1" is added to the value of each of the current counters Icnt[1] to Icnt[I1level] that are less than or equal to the current level I1level among the current counters Icnt[1] to Icnt[n].

[0118] Next, the load current characteristic calculation unit 17 determines whether the previous current level I0level is greater than the current current level I1level (step S52). When the processing unit 10 determines that the previous current level I0level is greater than the current current level I1level (step S52: Yes), the value of the current current counter Icnt, which has a current level Ilevel greater than the current current level I1level, is set to "0" (step S53).

[0119] Specifically, the load current characteristic calculation unit 17 returns the values ​​of current counters Icnt[I1level+1] to Icnt[I0level] corresponding to current levels Ilevel greater than the current level I1level in the current level range up to the previous current level I0level to “0”.

[0120] Next, when the processing of step S53 is completed, or when it is determined that the previous current level I0level is not greater than the current current level I1level (step S52: No), the load current characteristic calculation unit 17 determines whether the value of the current current counter Icnt[x] is greater than the value of the maximum current counter Icntm[x] (step S54).

[0121] Fig.10 The "x" shown in step S54 is an integer from "1" to "I1level". Therefore, in the process of step S54, it is determined whether the value of each of the current counters Icnt[1] to Icnt[I1level] is greater than the value of the corresponding maximum current counter Icntm among the multiple maximum current counters Icntm[1] to Icntm[I1level].

[0122] When the load current characteristic calculation unit 17 determines that the value of the current counter Icnt[x] is greater than the value of the maximum current counter Icntm[x] (step S54: Yes), it sets the value of the maximum current counter Icntm[x] to the same value as the current counter Icnt[x] (step S55).

[0123] For example, when the value of the current current counter Icnt[1] is greater than the value of the maximum current counter Icntm[1], the load current characteristic calculation unit 17 sets the value of the maximum current counter Icntm[1] to the same value as the current current counter Icnt[1]. In addition, when the value of the current current counter Icnt[1] is not greater than the value of the maximum current counter Icntm[1], the load current characteristic calculation unit 17 does not update the value of the maximum current counter Icntm[1].

[0124] In addition, when the value of the current current counter Icnt[I1level] is greater than the value of the maximum current counter Icntm[I1level], the load current characteristic calculation unit 17 sets the value of the maximum current counter Icntm[1] to the same value as the current current counter Icnt[I1level]. In addition, when the value of the current current counter Icnt[I1level] is not greater than the value of the maximum current counter Icntm[1], the load current characteristic calculation unit 17 does not update the value of the maximum current counter Icntm[I1level].

[0125] Next, when the processing of step S55 is completed, or when it is determined that the value of the current counter Icnt[x] is not greater than the value of the maximum current counter Icntm[x] (step S54: No), the load current characteristic calculation unit 17 calculates the value obtained by multiplying the value of the maximum current counter Icntm[x] by the processing routine time ΔTroop as the power-on time TxP[x] (step S56).

[0126] Fig.10 The "x" shown in step S56 is an integer from "1" to "I1level". Therefore, in the process of step S56, the load current characteristic calculation unit 17 calculates the power-on time TxP[1] to TxP[Ilevel] by multiplying the values ​​of the maximum current counters Icntm[1] to Icntm[Ilevel] by the processing routine time ΔTroop. When the load current characteristic calculation unit 17 ends the process of step S56, Fig.10 Processing shown.

[0127] Here, the TxP update process and the TxS update process are described in more detail. Fig.11 1 is a diagram showing an example of a load current when the load according to the first embodiment is a generator. Fig.11 The starting current flows as shown. Fig.11 In FIG. 1 , the vertical axis represents the instantaneous value of the load current, and the horizontal axis represents time. In addition, each cycle of the horizontal axis represents the cycle of the processing routine time ΔTroop.

[0128] exist Fig.11 In the example shown, the peak value of the load current is the largest in the first cycle, and then the peak value decreases as the generator accelerates to the rated speed. Fig.11The load current shown has a maximum peak value of 500% In in the first cycle. In addition, the extreme value of the load current decreases with the passage of time, and the peak value of the fifth cycle becomes 50% In, and the peak value of the sixth cycle and thereafter remains 50% In. "500% In" means a value of 500% of the rated current In, and "50% In" means a value of 50% of the rated current In.

[0129] Hereinafter, the unit current value Imin is set to 50% In. In the initial state, the initial value of each current counter Icnt[i] is "0", the initial value of each maximum current counter Icntm[i] is "0", and the initial value of each previous current level I0level[i] is "n".

[0130] Fig.12 It is used for Fig.11 The figure is used to explain the TxP update process of the first cycle. Fig.13 It is used for Fig.11 The figure illustrates the TxP update process of the second cycle. Fig.14 It is used for Fig.11 The figure illustrates the TxP update process of the third cycle. Fig.15 It is used for Fig.11 The figure illustrates the TxP update process of the 4th cycle. Fig.16 It is used for Fig.11 The figure shows the TxP update process of the 5th cycle. Fig.17 It is used for Fig.11 The figure shows the TxP update process of the 6th cycle. Fig.18 It is used for Fig.11 The figure shows the TxP update process of the 7th cycle. Fig.19 It is used for Fig.11 The figure shows the TxP update process of the 99th cycle.

[0131] In the first cycle, the load current peak value Ipeak is 500% In, so the processing unit 10 Fig.10 In the process of step S50 shown in FIG. 1 , the current current level I1level is calculated as “10” by the calculation of I1level=Ipeak / Imin=500%In / 50%In.

[0132] The current counters Icnt of the current level Ilevel that is less than or equal to the current level I1level are the current counters Icnt[1] to Icnt

[10] . Fig.10In step S51 shown, "1" is added to the values ​​of the current counters Icnt[1] to Icnt

[10] of this time.

[0133] In the first cycle, the previous current level I0level is "0". The processing unit 10 Fig.10 In step S52 shown in FIG. 1 , it is determined that I0level>I1level is not the case, and the process jumps to step S54. The processing unit 10 Fig.10 In step S54 shown, it is determined whether the value of each of the current current counters Icnt[1] to Icnt

[10] is greater than the value of the corresponding maximum current counter Icntm among the maximum current counters Icntm[1] to Icntm

[10] .

[0134] In the first cycle, the values ​​of the maximum current counters Icntm[1] to Icntm

[10] are "1". Therefore, the processing unit 10 Fig.10 In step S55 shown in FIG. 1 , the value of each maximum current counter Icntm[1] to Icntm

[10] , that is, "1", is set as the value of the current counter Icnt corresponding to the current counter Icnt[1] to Icnt

[10] .

[0135] Next, the processing unit 10 Fig.10 In step S56 shown, the processing routine time ΔTroop is multiplied by the value of the maximum current counter Icntm[1] to Icntm

[10] to calculate the power-on time TxP[1] to TxP

[10] . The processing routine time ΔTroop is 20 ms, so each power-on time TxP[1] to TxP

[10] is 20 ms.

[0136] Next, the processing of the processing unit 10 in the second cycle will be described. In the second cycle, the load current peak value Ipeak is 400%In, so the processing unit 10 Fig.10 In the process of step S50 shown in FIG. 1 , the current current level I1level is calculated as “8” by the calculation of Ipeak / Imin=400%In / 50%.

[0137] The current counters Icnt of the current level Ilevel that is less than or equal to the current level I1level are the current counters Icnt[1] to Icnt[8]. Fig.10 In step S51 shown in FIG. 1 , "1" is added to the current counters Icnt[1] to Icnt[8] at this time. The previous current level I0level was "10", so the processing unit 10 Fig.10In the process of step S53 shown in FIG. 1 , the values ​​of the current counters Icnt[9] and Icnt

[10] are set to “0”.

[0138] The processing unit 10 Fig.10 In step S54 shown in FIG. 1 , it is determined whether the value of each of the current current counters Icnt[1] to Icnt[8] is greater than the value of the corresponding maximum current counter Icntm among the maximum current counters Icntm[1] to Icntm[8]. The value of the current current counters Icnt[1] to Icnt[8] is "2", which is greater than the value of the maximum current counters Icntm[1] to Icntm[8]. Therefore, the processing unit 10 Fig.10 In step S55 shown in FIG. 1 , the value of each maximum current counter Icntm[1] to Icntm[8], that is, "2", is set as the value of the current counter Icnt corresponding to the current counter Icnt[1] to Icnt[8].

[0139] The processing unit 10 is as follows Figure 15 to Figure 19 As shown, for each cycle from the third cycle to the 99th cycle, the same processing as the first cycle and the second cycle is performed to calculate the conduction time TxP[1] to TxP

[10] . Thus, the processing unit 10 can calculate the conduction time TxP that matches the load current peak value Ipeak.

[0140] Next, the TxS update process is described. Fig. 20 It is used for Fig.11 The figure illustrates the TxS update processing of the first cycle and the second cycle. Fig.21 It is used for Fig.11 The figure illustrates the TxS update processing of the 3rd and 4th cycles shown. Fig. 22 It is used for Fig.11 The figure shows the TxS update process of the 5th and 6th cycles. Fig.23 It is used for Fig.11 The figure shows the TxS update processing of the 7th cycle and the 99th cycle.

[0141] The processing unit 10 Fig. 9 In the TxS update process shown, the value of each maximum current counter Icntm[x] is obtained by dividing the current accumulated current value S1 by the square of the value obtained by multiplying each of the multiple current levels Ilevel up to the current current level I1level by the unit current value Imin. In the following, the unit current value Imin is set to 50%In.

[0142] exist Fig. 20In the example shown, in the first cycle, the load current effective value Irms is 500%In, and the previous accumulated current value S2 is 0. Therefore, the current level I1level is 500%In / 50%In=10, and the current accumulated current value S1 is Irms 2 ×ΔTroop=500 2 ×0.02=5000.

[0143] The value of the current counter Icnt[1] is 5000÷(1×50) 2 =2, so the value of the maximum current counter Icntm[1] calculated by the processing unit 10 is as follows Fig. 20 The value of the current counter Icnt[2] is 5000÷(2×50). 2 =0.5, so the value of the maximum current counter Icntm[2] calculated by the processing unit 10 by rounding is as follows Fig. 20 "1" is shown.

[0144] In addition, the value of the current counter Icnt[3] is 5000÷(3×50) 2 =0.2, so by rounding, the value of the maximum current counter Icntm[3] calculated by the processing unit 10 is as follows: Fig. 20 Similarly, the values ​​of the maximum current counters Icntm[4] to Icntm

[10] calculated by the processing unit 10 are also as shown in Fig. 20 "0" is shown.

[0145] The processing unit 10 Fig. 9 In the TxS update process shown, the value of each maximum current counter Icntm[1] to

[10] is multiplied by the processing routine time ΔTroop, thereby calculating the power-on time TxS[1] to TxS

[10] . The power-on time TxS[1] is Icntm[1]×ΔTroop=2×20=40[ms]. The power-on time TxS[2] is Icntm[2]×ΔTroop=1×20=20[ms]. In addition, the power-on time TxS[3] to TxS

[10] is 0[ms].

[0146] exist Fig. 20 In the example shown, in the second cycle, the load current effective value Irms is 400% In. Therefore, the current level I1level is 400% In / 50% In=8, and the current cumulative current value S1 is S2+Irms 2 ×ΔTroop=5000+400 2 ×0.02=8200.

[0147] The value of the current counter Icnt[1] is 8200÷(1×50) 2 =3.28, so the value of the maximum current counter Icntm[1] calculated by the processing unit 10 is as follows Fig. 20 The value shown is "3". In addition, the value of the current counter Icnt[2] is 8200÷(2×50) 2 =0.82, so the value of the maximum current counter Icntm[2] calculated by the processing unit 10 is rounded off as follows: Fig. 20 "1" is shown.

[0148] In addition, the value of the current counter Icnt[3] is 8200÷(3×50) 2 =0.36, so by rounding off, the value of the maximum current counter Icntm[3] calculated by the processing unit 10 is as follows: Fig. 20 Similarly, the values ​​of the maximum current counters Icntm[4] to Icntm

[10] calculated by the processing unit 10 are also as shown in Fig. 20 "0" is shown.

[0149] The processing unit 10 multiplies the value of each maximum current counter Icntm[1] to

[10] by the processing routine time ΔTroop, thereby calculating the power-on time TxS[1] to TxS

[10] . The power-on time TxS[1] is Icntm[1]×ΔTroop=3×20=60[ms]. The power-on time TxS[2] is Icntm[2]×ΔTroop=2×20=20[ms]. In addition, the power-on time TxS[3] to TxS

[10] is 0ms.

[0150] The processing unit 10 is as follows Figure 21 to Figure 23 As shown, for each cycle from the third cycle to the 99th cycle, the same processing as the first and second cycles is performed to calculate the conduction time TxS[1] to TxS

[10] . Thus, the processing unit 10 can calculate the conduction time TxS that matches the load current effective value Irms.

[0151] Fig.24 FIG. 1 is a diagram showing an example of a hardware configuration of a processing unit of an electronic circuit breaker according to Embodiment 1. Fig.24 As shown, the processing unit 10 of the electronic circuit breaker 1 includes a computer having a processor 101 , a memory 102 , an AD converter 103 , an input / output interface 104 , and a communication device 105 .

[0152] The processor 101, the memory 102, the AD converter 103, the input / output interface 104, and the communication device 105 can transmit and receive data to each other through the bus 106, for example. The AD converter 11 is implemented by the AD converter 103. The communication unit 21 is implemented by the communication device 105. The output unit 20 is implemented by the input / output interface 104. The processor 101 reads and executes the program stored in the memory 102, thereby executing the functions of the peak value calculation unit 12, the effective value calculation unit 13, the instantaneous trip processing unit 14, the short-time limit trip processing unit 15, the long-time limit trip processing unit 16, the load current characteristic calculation unit 17, the advance warning processing unit 18, the recommended value calculation unit 19, and the setting unit 22. The processor 101 is, for example, an example of a processing circuit, and includes one or more of a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and a system LSI (Large Scale Integration).

[0153] The memory 102 includes one or more of RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory) and EEPROM (registered trademark) (Electrically Erasable Programmable Read Only Memory). In addition, the memory 102 includes a recording medium having a computer-readable program recorded thereon. The recording medium includes one or more of a nonvolatile or volatile semiconductor memory, a magnetic disk, a flexible memory, an optical disk, a compact disk and a DVD (Digital Versatile Disc). In addition, the electronic circuit breaker 1 may include an integrated circuit such as an ASIC (Application Specific Integrated Circuit) and an FPGA (Field Programmable Gate Array).

[0154] In addition, the control unit 54 of the information processing device 50 is composed of Fig.24 The processor 101 shown is composed of a memory 102, an AD converter 103, an input / output interface 104, and a bus 106. The processor 101 reads out and executes a program stored in the memory 102, thereby executing the functions of the display processing unit 60, the setting processing unit 61, and the recommended value calculation unit 62.

[0155] As described above, the electronic circuit breaker 1 according to the first embodiment includes the switch contact 4, the trip device 5, the current detection unit 7, the peak value calculation unit 12, the effective value calculation unit 13, the short-time trip processing unit 15, the long-time trip processing unit 16, the load current characteristic calculation unit 17, and the output unit 20. The switch contact 4 opens and closes the circuit 6 between the power supply 2 and the load 3. The trip device 5 changes the switch contact 4 from the closed state to the open state. The current detection unit 7 detects the current flowing in the circuit 6. The peak value calculation unit 12 calculates the load current peak value Ipeak which is the peak value of the current detected by the current detection unit 7. The effective value calculation unit 13 calculates the load current effective value Irms which is the effective value of the current detected by the current detection unit 7. When the short-time trip processing unit 15 determines that an overcurrent flows in the circuit 6 in the short-time region based on the load current peak value Ipeak, it causes the trip device 5 to change the switch contact 4 from the closed state to the open state. When it is determined based on the load current effective value Irms that an overcurrent flows in the circuit 6 in the long time region, which is a time region longer than the short time region, the long time region, the long time limit trip processing unit 16 causes the trip device 5 to change the switch contact 4 from the closed state to the open state. The load current characteristic calculation unit 17 calculates the current characteristic of the load 3 in the short time region, i.e., the short time limit load current characteristic, based on the load current peak value Ipeak, and calculates the current characteristic of the load 3 in the long time region, i.e., the long time limit load current characteristic, based on the load current effective value Irms. The output unit 20 outputs information on the load current time characteristic including the short time limit load current characteristic and the long time limit load current characteristic calculated by the load current characteristic calculation unit 17. Thus, the electronic circuit breaker 1 can present the load current time characteristic that matches the overcurrent tripping action characteristic to the user, so that the user can appropriately perform the overcurrent tripping action characteristic.

[0156] In addition, the load current characteristic calculation unit 17 calculates the long-time load current characteristic based on the load current effective value Irms and the load current peak value Ipeak. Thus, the electronic circuit breaker 1 can calculate the long-time load current characteristic with high accuracy.

[0157] In addition, the electronic circuit breaker 1 includes a pre-alarm processing unit 18 and a recommended value calculation unit 19. The pre-alarm processing unit 18 determines whether a pre-alarm is necessary based on the pre-alarm operating characteristic that is defined by the pre-alarm current threshold Ip, which is a threshold lower than the overcurrent determination threshold defined by the overcurrent trip operating characteristic. The recommended value calculation unit 19 calculates the recommended value of the pre-alarm operating characteristic based on the information of the load current time characteristic and the information of the overcurrent trip operating characteristic. Thus, in the electronic circuit breaker 1, the user can appropriately adjust the pre-alarm operating characteristic.

[0158] In addition, the circuit breaker system 100 according to the first embodiment includes an electronic circuit breaker 1 and an information processing device 50 connected to the electronic circuit breaker 1 so as to be communicable. The electronic circuit breaker 1 includes a pre-alarm processing unit 18 that determines whether a pre-alarm is necessary based on a pre-alarm operation characteristic that specifies a pre-alarm current threshold Ip, which is a threshold lower than the overcurrent determination threshold specified by the overcurrent trip operation characteristic. The information processing device 50 includes a communication unit 51 and a recommended value calculation unit 62. The communication unit 51 receives information on the load current time characteristic and the overcurrent trip operation characteristic from the electronic circuit breaker 1. The recommended value calculation unit 62 calculates a recommended value of the pre-alarm current threshold Ip based on the information on the load current time characteristic and the overcurrent trip operation characteristic received by the communication unit 51. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristic.

[0159] In addition, the communication unit 51 transmits the recommended value information including the information of the recommended value of the pre-alarm current threshold Ip calculated by the recommended value calculation unit 62 to the electronic circuit breaker 1. The electronic circuit breaker 1 includes a setting unit 22 that sets the information of the pre-alarm operation characteristics in the pre-alarm processing unit 18 based on the recommended value information transmitted from the information processing device 50. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristics.

[0160] In addition, the communication unit 51 transmits the recommended value information including the information of the recommended value of the pre-alarm current threshold Ip calculated by the recommended value calculation unit 62 to the electronic circuit breaker 1. The electronic circuit breaker 1 has an input unit 31 having a dial for setting the information of the pre-alarm operation characteristics in the pre-alarm processing unit 18. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristics.

[0161] The configuration described in the above embodiment is an example of the content of the present invention, and can be combined with other known technologies. Part of the configuration can be omitted or changed without departing from the scope of the present invention.

[0162] Description of the label

[0163] 1 Electronic circuit breaker, 2 Power supply, 3 Load, 4, 41, 42, 43 Open / Close contacts, 5 Trip device, 6, 61, 62, 63 Circuit, 7 Current detection unit, 9 Voltage conversion unit, 10 Processing unit, 11 AD conversion unit, 12 Peak value calculation unit, 13 Effective value calculation unit, 14 Instantaneous trip processing unit, 15 Short-time trip processing unit, 16 Long-time trip processing unit, 17 Load current characteristic calculation unit, 18 Pre-alarm processing unit, 19, 62 Recommended value calculation unit, 20 Output unit, 21, 51 Communication unit, 22 Setting unit, 30 Trip circuit, 31, 53 Input unit, 32 Notification unit, 50 Information processing device, 52 Display unit, 54 Control unit, 55 Storage unit, 60 Display processing unit, 61 Setting processing unit, 100 Circuit breaker system

Claims

1. An electronic circuit breaker, characterized in that: have: Open and close contacts, which open and close the circuit between the power source and the load; a tripping device that sets the switch contacts from a closed state to an open state; a current detection unit for detecting a current flowing in the circuit; a peak value calculation unit that calculates a peak value of the current detected by the current detection unit; an effective value calculation unit that calculates an effective value of the current detected by the current detection unit; a short-time limit trip processing unit that causes the trip device to change the switching contact from a closed state to an open state when it is determined that an overcurrent flows in the circuit in a short-time limit region based on the peak value calculated by the peak value calculating unit; a long-limit time trip processing unit for causing the trip device to change the switch contact from a closed state to an open state when it is determined based on the effective value calculated by the effective value calculation unit that an overcurrent flows in the circuit in a region of a long limit time that is longer than the short limit time; a load current characteristic calculation unit that calculates the current characteristic of the load in the short-time region, i.e., the short-time load current characteristic, based on the peak value calculated by the peak value calculation unit, and calculates the current characteristic of the load in the long-time region, i.e., the long-time load current characteristic, based on the effective value calculated by the effective value calculation unit; an output unit that outputs information on the load current time characteristics including the short-term load current characteristics and the long-term load current characteristics calculated by the load current characteristics calculation unit, a pre-alarm processing unit that determines whether a pre-alarm is necessary based on a pre-alarm operation characteristic that specifies a pre-alarm current threshold value, the pre-alarm current threshold value being a threshold value lower than an overcurrent determination threshold value specified by an overcurrent trip operation characteristic including the overcurrent detection characteristics of each of the short-time limit trip processing unit and the long-time limit trip processing unit; as well as a recommended value calculation unit that calculates a recommended value of the advance warning action characteristic based on the information of the load current time characteristic and the information of the overcurrent trip action characteristic, The output unit outputs the recommended value calculated by the recommended value calculation unit.

2. The electronic circuit breaker according to claim 1, characterized in that The load current characteristic calculation unit calculates the long-time load current characteristic based on the effective value calculated by the effective value calculation unit and the peak value calculated by the peak value calculation unit.

3. A circuit breaker system comprising: The electronic circuit breaker according to claim 1 or 2; and an information processing device connected to the electronic circuit breaker so as to be communicable, The electronic circuit breaker includes a pre-alarm processing unit that determines whether a pre-alarm is necessary based on a pre-alarm operation characteristic that specifies a pre-alarm current threshold value, the pre-alarm current threshold value being a threshold value lower than an overcurrent determination threshold value specified by an overcurrent trip operation characteristic including the overcurrent detection characteristics of each of the short-time limit trip processing unit and the long-time limit trip processing unit, The information processing device comprises: a communication unit that receives the information of the load current time characteristic and the information of the overcurrent tripping operation characteristic from the electronic circuit breaker; and A recommended value calculation unit calculates a recommended value of the advance warning current threshold value based on the information on the load current time characteristic and the information on the overcurrent tripping operation characteristic received by the communication unit.

4. The circuit breaker system according to claim 3, characterized in that the communication unit transmits recommended value information including information on the recommended value of the advance warning current threshold value calculated by the recommended value calculation unit to the electronic circuit breaker; The electronic circuit breaker includes a setting unit that sets the information of the advance warning operation characteristics in the advance warning processing unit based on the recommended value information transmitted from the information processing device.

5. The circuit breaker system according to claim 3, characterized in that the communication unit transmits recommended value information including information on the recommended value of the advance warning current threshold value calculated by the recommended value calculation unit to the electronic circuit breaker; The electronic circuit breaker includes an input unit having a dial for setting the information of the advance warning operation characteristics in the advance warning processing unit.

Images