Charging voltage display device and power equipment

Abstract

To provide a charging voltage display device that can clearly determine the discharge state of a storage unit.SOLUTION: A charging voltage display device includes a power storage unit 10, a power storage unit discharge circuit 20 connected in parallel to the power storage unit 10 and configured to discharge charge of the power storage unit 10, and a first series circuit connected in parallel to the power storage unit 10 and connecting a charging voltage display circuit 30 for the power storage unit 10 in series to a Zener diode 50. The Zener voltage threshold Vz of the Zener diode 50 is set to be greater than the turn-off voltage Voff of the charging voltage display circuit 30 and equal to or less than the working upper limit voltage Vwork.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a charging voltage display device and an electric power device. [Background technology]

[0002] Conventionally, a power conversion device includes a power converter including a main circuit including a capacitor, a discharge circuit provided to discharge the charge of the capacitor, and a capacitor voltage monitoring circuit connected in parallel with the capacitor, The capacitor voltage monitoring circuit includes a first series circuit including a plurality of first light emitting elements connected in series; a second series circuit connected in parallel to the first series circuit and including a plurality of second light-emitting elements connected in series; There has been a device in which the magnitude of the voltage across the first series circuit when a current flows that causes the first light-emitting element to emit light is different from the magnitude of the voltage across the second series circuit when a current flows that causes the second light-emitting element to emit light (see Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-102905 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional patent documents mentioned above, when the remaining voltage of the capacitor is very small, the on / off state of the light-emitting element (LED, etc.) of the capacitor voltage monitoring circuit becomes unclear and indistinguishable, and there is a possibility that an operator may misjudge whether the light is off, i.e., whether the capacitor is in a discharged state.

[0005] The present disclosure discloses a technique for solving the above-mentioned problems, and aims to provide a charging voltage display device and power equipment that can clearly determine the discharge state of a power storage unit. [Means for solving the problem]

[0006] The charging voltage display device of the present disclosure includes: A power storage unit; a power storage unit discharge circuit connected in parallel to the power storage unit and configured to discharge the charge of the power storage unit; a first series circuit connected in parallel to the power storage unit, in which a charging voltage display circuit for the power storage unit and a Zener diode are connected in series; The Zener voltage threshold of the Zener diode is set to be higher than the light-off voltage of the charging voltage display circuit and lower than the upper working voltage limit.

[0007] The electric power device of the present disclosure includes the charging voltage display device, and also includes an electromagnetic operation mechanism that is operated by energy stored in the power storage unit of the charging voltage display device. [Effects of the Invention]

[0008] The charging voltage display device and power device of the present disclosure have the effect of making it possible to clearly determine the discharge state of the power storage unit. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 10 is a diagram showing the configuration of a charging voltage display device according to a reference example. [Figure 2] 10 is a graph showing the voltage during discharge of the storage unit and the on / off state of the charging voltage display circuit in the charging voltage display device according to the reference example. [Figure 3] 1 is a diagram showing a configuration of a charging voltage display device according to a first embodiment. [Figure 4] 4 is a graph showing the voltage during discharge of the power storage unit and the on / off state of the charging voltage display circuit in the charging voltage display device in accordance with Embodiment 1. [Figure 5] FIG. 4 is a diagram showing another configuration of the charging voltage display device in accordance with the first embodiment. [Figure 6]FIG. 4 is a diagram showing another configuration of the charging voltage display device in accordance with the first embodiment. [Figure 7] FIG. 10 is a diagram showing the configuration of a charging voltage display device according to a second embodiment. [Figure 8] FIG. 10 is a diagram showing the configuration of an electric power device equipped with a charging voltage display device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] References to this disclosure. Before describing the embodiments of the present disclosure, a charging voltage display device according to a reference example will be described in order to clarify the features of the embodiments of the present disclosure. FIG. 1 is a diagram showing the configuration of a charging voltage display device according to a reference example, and FIG. 2 is a graph showing the on / off state of a charging voltage display circuit when a power storage unit in the charging voltage display device according to the reference example is being discharged.

[0011] A charging voltage display device 1100 of the reference example shown in FIG. 1 includes a capacitor 10 as a power storage unit between a positive electrode terminal 1 and a negative electrode terminal 2. Charging voltage display device 1100 also includes a storage unit discharge circuit 20 connected in parallel to capacitor 10 to discharge the charge of capacitor 10. The power storage unit discharge circuit 20 has a discharge switch 200 and a discharge resistor 210 . Furthermore, the charging voltage display device 1100 includes a charging voltage display circuit 30 connected in parallel to the capacitor 10. The charging voltage display circuit 30 includes a limiting resistor 300 and a light-emitting element circuit configured with a light-emitting element 310 (e.g., an LED (Light Emitting Diode)). Although FIG. 1 shows an example in which the light emitting element circuit is configured from one light emitting element 310, a plurality of light emitting elements 310 may be connected in series.

[0012] Next, the operation of the charging voltage display device according to the reference example of FIG. 1 will be described. Here, an example will be described in which a circuit breaker having an electromagnetic operation mechanism is connected as power equipment to the positive terminal 1 and the negative terminal 2 of the capacitor 10. As will be described in the following embodiment 3, in a circuit breaker having an electromagnetic operating mechanism, energy stored in capacitor 10 through charging is passed through a coil to generate electromagnetic force, which then operates the circuit breaker. The capacitor 10 for driving the circuit breaker is always in a charged state in order to drive the circuit breaker, and when in a charged state, the light emitting element 310 is turned on. Incidentally, when a circuit breaker is inspected or replaced at regular or irregular intervals, the connection wire of the capacitor 10 may be disconnected, and during the disconnection work, the capacitor 10 needs to be discharged. In this case, it is conceivable to press the discharge switch 200 of the storage unit discharge circuit 20 to discharge the capacitor 10 via the discharge resistor 210, and determine whether the charging voltage of the capacitor 10 has dropped to a voltage at which work can be performed by checking the on and off states of the light-emitting element 310.

[0013] FIG. 2 is a graph showing the voltage during discharge of the power storage unit and the on and off states of the charging voltage display circuit in the charging voltage display device according to the reference example. 2, the vertical axis represents the voltage V of the power storage unit (capacitor 10), and the horizontal axis represents time t. The turn-off voltage of charging voltage display circuit 30 is represented by Voff. Area A represents the lit area of the charging voltage display circuit 30, area B represents the unclear area where the charging voltage display circuit 30 is lit or not lit, and area C represents the not lit area of the charging voltage display circuit 30.

[0014] In Figure 2, the light-emitting element 310 of the charging voltage display circuit 30, for example an LED element, lights up even with a very small current, so there are areas where it is difficult for the operator to visually determine whether the element is on or off, and there is always an area B where it is unclear whether the element is on or off. In other words, when the remaining voltage of the capacitor 10 is very small, the on / off state of the charging voltage display circuit 30 becomes unclear and unclear, and there is a possibility that different operators will make different judgments as to whether the charging voltage display circuit 30 is off, i.e., whether the capacitor 10 is in a discharged state.

[0015] The embodiment of the present disclosure described below has been made to solve the problems of the charging voltage display device of the reference example of Figures 1 and 2, and makes it possible to clearly determine the discharge state of the storage unit.

[0016] Embodiment 1 FIG. 3 is a diagram showing the configuration of the charging voltage display device according to embodiment 1, and FIG. 4 is a graph showing the voltage when the storage unit is discharging in the charging voltage display device according to embodiment 1 and the on / off state of the charging voltage display circuit.

[0017] The charging voltage display device 1000 of the first embodiment shown in FIG. 3 includes a capacitor 10 as a power storage unit between the positive electrode terminal 1 and the negative electrode terminal 2. The capacitor 10 serves as a power storage unit. Charging voltage display device 1000 also includes a power storage unit discharge circuit 20 that is connected in parallel to capacitor 10 as a power storage unit and that discharges the charge of capacitor 10. The power storage unit discharge circuit 20 has a discharge switch 200 and a discharge resistor 210 . Furthermore, the charging voltage display device 1000 includes a charging voltage display circuit 30 connected in parallel to the capacitor 10. The charging voltage display circuit 30 includes a limiting resistor 300 and a light-emitting element circuit configured with a light-emitting element 310 (e.g., an LED (Light Emitting Diode)). Although FIG. 3 shows an example in which the light emitting element circuit is configured from one light emitting element 310, a plurality of light emitting elements 310 may be connected in series.

[0018] The above configuration is the same as the reference example in Figure 1, but in embodiment 1, a Zener diode 50 is connected in series to the charging voltage display circuit 30, and is connected in parallel to the capacitor 10 as the storage unit, thereby providing a first series circuit 60 consisting of the charging voltage display circuit 30 and the Zener diode 50. The Zener voltage threshold Vz of the Zener diode 50 is set to be greater than the turn-off voltage Voff of the charging voltage display circuit 30 and equal to or less than the working upper limit voltage Vwork.

[0019] FIG. 4 is a graph showing the voltage during discharge of the power storage unit and the on / off state of the charging voltage display circuit in the charging voltage display device in accordance with Embodiment 1. In FIG. 4, the vertical axis represents the voltage V of the capacitor 10 as the power storage unit, and the horizontal axis represents time t. The upper working voltage limit is represented by Vwork, the Zener voltage threshold is represented by Vz, and the off voltage of the charging voltage display circuit 30 is represented by Voff. Area A represents the lit area of the charging voltage display circuit 30, area B represents the unclear area where the charging voltage display circuit 30 is lit or not lit, and area C represents the not lit area of the charging voltage display circuit 30. 4, when the charging voltage of capacitor 10 serving as the power storage unit falls below Zener voltage threshold Vz, the current flowing to charging voltage display circuit 30 becomes zero, and charging voltage display circuit 30 turns off. The Zener voltage threshold Vz can be selected when selecting Zener diode 50, and is set so that Zener voltage threshold Vz is equal to or lower than the upper working voltage Vwork. The Zener voltage threshold Vz is also set so that it is greater than the turn-off voltage Voff of charging voltage display circuit 30.

[0020] Here, the charging voltage of capacitor 10 as the power storage unit is assumed to be 150 volts to 190 volts in the case of a capacitor for driving a circuit breaker, for example. The off voltage Voff of the charging voltage display circuit 30 is assumed to be, for example, about 1 volt when the Zener diode 50 is not provided. The upper limit work voltage Vwork is a voltage that will not injure the worker, and although it varies depending on the situation, it is assumed to be around 10 volts. The Zener voltage threshold Vz is assumed to be 5 to 10 volts.

[0021] As described above, in the first embodiment, it is possible to determine whether the charging voltage display circuit 30 is on or off when the charging voltage of the capacitor 10 serving as the power storage unit reaches the Zener voltage threshold Vz, thereby eliminating variations in the on and off states due to visual inspection by the operator.

[0022] Furthermore, in the reference example charging voltage display device 1100 of Figures 1 and 2, in order to ensure work safety, the worker does not visually determine whether the charging voltage display circuit 30 is on or off, but instead presses the discharge switch 200 during the discharge time T2 of the capacitor 10 shown in Figure 4 to sufficiently lower the work upper limit voltage Vwork before starting work. In contrast to this, in the first embodiment, the time required to press the discharge switch 200 is only the discharge time T1, which is shorter than the previous discharge time T2, and the working time can be shortened.

[0023] In the above description of the first embodiment (FIGS. 3 and 4), a capacitor 10 (e.g., an aluminum electrolytic capacitor, a ceramic capacitor, etc.) is used as the power storage unit. However, as shown in FIG. 5, a capacitor 11 (e.g., an electric double layer capacitor, a lithium ion capacitor, etc.) may be used as the power storage unit. Also, as shown in FIG. 6, a storage battery 12 may be used as the power storage unit. Note that in FIGS. 5 and 6, the configuration other than the capacitor 11 and storage battery 12 as the power storage unit is the same as the configuration in FIGS. 3 and 4.

[0024] As described above, according to the first embodiment, the power storage unit and a power storage unit discharge circuit connected in parallel to the power storage unit and configured to discharge the charge of the power storage unit; a first series circuit connected in parallel to the power storage unit, in which a charging voltage display circuit for the power storage unit and a Zener diode are connected in series; The Zener voltage threshold of the Zener diode is set to be higher than the light-off voltage of the charging voltage display circuit and lower than the upper working voltage limit. This has the effect of making it possible to clearly determine the discharge state of the power storage unit.

[0025] Embodiment 2 FIG. 7 is a diagram showing the configuration of a charging voltage display device according to the second embodiment. The light emitting element circuit of the charging voltage display device of the second embodiment is configured by arranging light emitting element series circuits, each of which has a plurality of light emitting elements connected in series, in parallel in multiple rows.

[0026] In the example shown in Figure 7, the light-emitting element circuit is constructed by arranging in parallel a light-emitting element series circuit in which two light-emitting elements 311 and 312 are connected in series, and a light-emitting element series circuit in which two light-emitting elements 321 and 322 are connected in series.

[0027] Here, a light emitting element (for example, an LED element) may have an open circuit failure or a short circuit failure mode. An open circuit failure of a light emitting element is a failure in which current cannot be supplied to the light emitting element due to a broken wire or the like, and the light emitting element is no longer able to emit light. A short circuit failure of a light emitting element is a failure in which a short circuit occurs due to melting of a wire or a joint, etc., and current cannot be supplied to the light emitting element, making it unable to emit light. In this embodiment, even if a light-emitting element constituting a light-emitting element circuit suffers an open circuit failure or a short circuit failure, it is possible to enable other light-emitting elements constituting the light-emitting element circuit to emit light.

[0028] 7, if capacitor 10 is in a charged state and light-emitting element 311 experiences an open circuit fault, light-emitting elements 311 and 312 are turned off and light-emitting elements 321 and 322 are turned on. In other words, the two light-emitting elements 321 and 322 are turned on, so the charged state of capacitor 10 can be determined. When capacitor 10 is in a charged state and light-emitting element 311 experiences a short-circuit failure, light-emitting element 311 goes out and light-emitting elements 312, 321, and 322 go on. That is, the three light-emitting elements 312, 321, and 322 are in a lit state, so the charged state of capacitor 10 can be determined. If both light-emitting element 311 and light-emitting element 321 experience an open circuit failure, all four light-emitting elements 311, 312, 321, and 322 will be turned off even if capacitor 10 is in a charged state. However, since the probability of two light-emitting elements simultaneously experiencing an open circuit failure is low in a parallel circuit of light-emitting element series circuits, this can be excluded from consideration. However, even in this case, the problem can be resolved by arranging light-emitting element series circuits, in which multiple light-emitting elements are connected in series, in parallel in three or more rows.

[0029] As described above, according to the second embodiment, the light-emitting element circuit is configured by arranging a plurality of light-emitting element series circuits, each of which has a plurality of light-emitting elements connected in series, in parallel in a plurality of rows. Even if an open circuit failure or a short circuit failure occurs in a light emitting element constituting the light emitting element circuit, it is possible to enable other light emitting elements constituting the light emitting element circuit to emit light.

[0030] Embodiment 3 Embodiment 3 describes an electric power device that includes the charging voltage display device described in embodiment 1 or 2 and also has an electromagnetic operating mechanism that is operated by energy stored in the storage unit of the charging voltage display device.

[0031] FIG. 8 is a diagram showing the configuration of an electric power device including a charging voltage display device according to the third embodiment. In FIG. 8, a vacuum circuit breaker will be described as an example of power equipment having an electromagnetic operation mechanism that is operated by the energy of a charged power storage unit.

[0032] As shown in FIG. 8, the vacuum circuit breaker 1030 is installed in a tank shielding wall 1011 and includes a vacuum switch tube 1015 in which a fixed contact 1012 and a movable contact 1014 attached to a movable shaft 1013 are opened and closed. An electromagnetic operating mechanism 1025 having the function of opening and closing contacts 1012 and 1014 of a vacuum switch tube 1015 is disposed outside the tank shielding wall 1011 . The electromagnetic operating mechanism 1025 comprises a fixed core 1016, a tripping coil 1017 and a closing coil 1018 installed within the fixed core 1016, a capacitor 10 within the charging voltage display device 1000 that supplies power to the tripping coil 1017, a movable shaft 1021 installed so as to pass through the tripping coil 1017 and the closing coil 1018, a permanent magnet 1022 attached to the movable shaft 1021, and a movable core 1023, and serves to open and close the contacts 1012, 1014 of the vacuum switch tube 1015 using a contact pressure spring 1024 attached to the movable shaft 1021. The configuration of the charging voltage display device 1000 is the same as that of the first embodiment, and therefore a description thereof will be omitted.

[0033] Next, the operating principle of the vacuum circuit breaker according to the third embodiment will be described with reference to FIG. The opening and closing operation of the vacuum circuit breaker 1030 is performed by the electromagnetic force of coils 1017 and 1018 of an electromagnetic operating mechanism 1025, and the open / closed state is maintained by the magnetic force of a permanent magnet 1022. A tripping coil 1017 and a closing coil 1018 are provided on the fixed core 1016, and a movable shaft 1021 to which a movable core 1023 and a permanent magnet 1022 are attached is set so as to be able to move between the tripping coil 1017 and the closing coil 1018, and this movable shaft 1021 is connected via a contact pressure spring 1024 to a movable shaft 1013 on the vacuum switch tube 1015 side which is connected to a movable contact 1014 opposing a fixed contact 1012 of the vacuum switch tube 1015. When the vacuum switch tube 1015 is in the closed state, the movable iron core 1023 is attracted and held by the permanent magnet 1022 on the closed side of the fixed iron core 1016 . When a tripping command is issued to open the vacuum switch tube 1015, the tripping coil 1017 is energized from the capacitor 10 via the switch 1019, and the magnetic force attracts the movable core 1023 to the open side, and the movable core 1023 is attracted and held on the open side by the permanent magnet 1022 even after the current to the tripping coil 1017 is stopped. This causes the movable shaft 1021 to which the movable core 1023 is attached to move, and the contacts of the vacuum switch tube 1015 are opened.

[0034] Although the above embodiment has been described as being applied to a charge voltage display device for a storage battery unit used to drive a vacuum circuit breaker as an example of power equipment, the present invention can also be applied to other power equipment that uses a storage battery unit as a driving energy source. Furthermore, when applied to a storage battery unit for a vehicle such as an automobile, the present invention has the effect of enabling the discharge state of the storage battery unit to be clearly determined when disconnecting the storage battery unit.

[0035] As described above, according to the third embodiment, it is possible to provide an electric power device that includes the charging voltage display device of the first and second embodiments and also includes an electromagnetic operation mechanism that is operated by the energy stored in the storage unit of the charging voltage display device. This has the effect of making it possible to clearly determine the discharge state of the storage unit when performing work to unwind the storage unit.

[0036] Although the present disclosure describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not exemplified are conceivable within the scope of the technology disclosed in this specification, including, for example, cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with components of another embodiment.

[0037] Various aspects of the present disclosure are summarized below as appendices.

[0038] (Appendix 1) A power storage unit; a power storage unit discharge circuit connected in parallel to the power storage unit and configured to discharge the charge of the power storage unit; a first series circuit connected in parallel to the power storage unit, in which a charging voltage display circuit for the power storage unit and a Zener diode are connected in series; A charging voltage display device in which the Zener voltage threshold of the Zener diode is set to be higher than the light-off voltage of the charging voltage display circuit and lower than the upper operating voltage limit. (Appendix 2) 2. The charging voltage display device according to claim 1, wherein the charging voltage display circuit is configured by connecting a limiting resistor and a light-emitting element circuit in series. (Appendix 3) 3. The charging voltage display device according to claim 2, wherein the light-emitting element circuit is configured by arranging a plurality of light-emitting element series circuits, each of which has a plurality of light-emitting elements connected in series, in parallel in multiple rows. (Appendix 4) 4. The charging voltage display device according to claim 1, wherein the power storage unit discharge circuit includes a discharge switch and a discharge resistor. (Appendix 5) An electric power device comprising the charging voltage display device according to any one of Supplementary Note 1 to Supplementary Note 4, and also comprising an electromagnetic operating mechanism that is operated by energy stored in the storage unit of the charging voltage display device. (Appendix 6) The electric power device according to claim 5, wherein the electric power device is a circuit breaker, and the electromagnetic operation mechanism performs an opening and closing operation of the circuit breaker. [Explanation of symbols]

[0039] 1 positive terminal, 2 negative terminal, 10 capacitor, 11 capacitor, 12 storage battery, 20 storage unit discharge circuit, 30 charging voltage display circuit, 50 Zener diode, 60 first series circuit, 200 discharge switch, 210 discharge resistor, 300 limiting resistor, 310,311,312,321,322 Light emitting element, 1000 Charging voltage indicator.

Claims

1. A power storage unit; a power storage unit discharge circuit connected in parallel to the power storage unit and configured to discharge the charge of the power storage unit; a first series circuit connected in parallel to the power storage unit, the first series circuit including a charging voltage display circuit for the power storage unit and a Zener diode connected in series; A charging voltage display device in which the Zener voltage threshold of the Zener diode is set to be higher than the light-off voltage of the charging voltage display circuit and lower than the upper operating voltage limit.

2. 2. A charging voltage display device according to claim 1, wherein said charging voltage display circuit is constructed by connecting a limiting resistor and a light emitting element circuit in series.

3. 3. A charging voltage display device according to claim 2, wherein said light emitting element circuit is configured by arranging a plurality of light emitting element series circuits, each of which has a plurality of light emitting elements connected in series, in parallel in a plurality of rows.

4. The charging voltage display device according to claim 1 , wherein the electric storage unit discharge circuit includes a discharge switch and a discharge resistor.

5. 4. An electric power device comprising the charging voltage display device according to claim 1, and an electromagnetic operation mechanism operated by energy stored in a power storage unit of the charging voltage display device.

6. 6. The electric power device according to claim 5, wherein the electric power device is a circuit breaker, and the electromagnetic operation mechanism performs an opening and closing operation of the circuit breaker.

Images