Flowmeter with induction electricity taking device

Abstract

The utility model provides a flow meter with an induction electricity taking device, the flow meter comprises the induction electricity taking device and a flow meter body, and the induction electricity taking device comprises an electromagnetic induction device, a protection circuit, a rectification filter circuit, a voltage protection energy discharge circuit and a voltage conversion circuit which are connected in sequence. The electromagnetic induction device is nested on a high-voltage bus to generate a first alternating-current voltage, the protection circuit limits the first alternating-current voltage within a first voltage range, and the rectification filter circuit converts the first alternating-current voltage within the first voltage range into a first direct-current voltage. The voltage protection energy leakage circuit limits the first direct-current voltage within a second voltage range, the voltage conversion circuit reduces the first direct-current voltage within the second voltage range to a third voltage range, output voltage is generated, and power is stably supplied to the flowmeter body. According to the flow meter, a battery does not need to be frequently replaced, safe current is stably obtained from a high-voltage bus for a long time through the induction electricity taking device, and the safety and continuity of the flow meter are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent meter, and particularly to a flowmeter with an inductive power taking device. BACKGROUND

[0002] Intelligent flowmeters (such as intelligent gas meters, intelligent water meters, and intelligent electricity meters, hereinafter referred to as flowmeters) are generally powered by batteries, and the service life of the battery is generally three to five years. When the battery is damaged or runs out of power, the device will not work normally, and battery replacement is required at this time.

[0003] The service life of the battery is affected by various factors. For example, when the frequency of use of the flowmeter is high or frequent communication with the outside is required, the battery power will be depleted faster. For example, alkaline batteries will perform significantly worse in low-temperature environments, and if the flowmeter is used in cold regions, the battery will be damaged faster. Shortening the service life of the battery means that the flowmeter needs to be replaced more frequently, resulting in higher maintenance costs, and the process of replacing the battery for the flowmeter is cumbersome and requires consideration of battery compatibility with the flowmeter. For example, for a gas meter, when replacing the battery, the valve needs to be closed first, the small cover needs to be opened, and the sulfuric acid paper bag inside needs to be removed. If the battery is installed incorrectly or an incompatible battery is installed, it will affect the normal use of the gas meter. CONTENT OF THE INVENTION

[0004] The present application provides a flowmeter with an inductive power taking device to improve the safety and sustainability of the flowmeter.

[0005] The present application provides a flowmeter with an inductive power taking device, comprising: an inductive power taking device and a flowmeter body;

[0006] The inductive power taking device comprises an electromagnetic induction device, a protection circuit, a rectifier filter circuit, a voltage protection energy discharge circuit, and a voltage conversion circuit connected in sequence;

[0007] The electromagnetic induction device is used to be nested on a high-voltage bus and generates a first alternating voltage based on the principle of electromagnetic induction;

[0008] The protection circuit is used to limit the first alternating voltage generated by the electromagnetic induction device within a first voltage range when a surge current occurs on the high-voltage bus, and output a second alternating voltage within the first voltage range to the rectifier filter circuit;

[0009] The rectifier filter circuit converts the second alternating voltage into a first direct current voltage and outputs the first direct current voltage to the voltage protection energy discharge circuit;

[0010] The voltage protection energy discharge circuit is configured to limit the first DC voltage within a second voltage range when a surge current occurs in the high-voltage bus, and output a second DC voltage within the second voltage range to the voltage conversion circuit;

[0011] The voltage conversion circuit is configured to reduce the second DC voltage to a third voltage range, and generate an output voltage;

[0012] The output voltage of the voltage conversion circuit is used to power the flowmeter body.

[0013] In an implementation, the flowmeter further comprises an energy storage device,

[0014] The output voltage of the voltage conversion circuit is used as a charging power source of the energy storage device.

[0015] In an implementation, the flowmeter further comprises a power supply switching circuit, the power supply switching circuit comprising an input end and an output end,

[0016] The output end of the power supply switching circuit is connected to a voltage input end of the flowmeter body,

[0017] The input end of the power supply switching circuit is connected to the output end of the voltage conversion circuit and a voltage output end of the energy storage device, respectively,

[0018] The power supply switching circuit is configured to switch a power supply of the flowmeter body.

[0019] In an implementation, the flowmeter body comprises an electronic watch head and a flowmeter device, the electronic watch head comprising a control unit;

[0020] The control unit is configured to control the power supply switching circuit to switch the power supply of the flowmeter body to the energy storage device when the output voltage of the voltage conversion circuit is lower than a preset voltage threshold.

[0021] In an implementation, the control unit is further configured to:

[0022] When the electronic watch head communicates with an external device, control the power supply switching circuit to switch the power supply of the flowmeter body to the energy storage device;

[0023] The energy storage device is any one of an alkaline battery, a lithium battery, a nickel-hydrogen battery, and a super capacitor.

[0024] In an implementation, the protection circuit comprises a surge protector,

[0025] The surge protector is used to limit the transient overvoltage generated by the electromagnetic induction device to the first voltage range when the surge current is generated on the high-voltage bus, and output a second alternating voltage in the first voltage range.

[0026] In an implementation manner, the protection circuit includes a flat wave reactance, the flat wave reactance is connected in series with the electromagnetic induction device, an output of the flat wave reactance is connected with an input of the surge protector,

[0027] The flat wave reactance is used to share the transient overvoltage generated by the electromagnetic induction device when the surge current is generated on the high-voltage bus.

[0028] In an implementation manner, the rectification filter circuit includes a rectification circuit and a filter circuit,

[0029] An input end of the rectification circuit is connected with an output end of the protection circuit, the rectification circuit converts the second alternating voltage into a third direct current voltage, and outputs the third direct current voltage to the filter circuit;

[0030] An output end of the filter circuit is connected with an input end of the voltage protection energy discharge circuit, the filter circuit filters the third direct current voltage, and outputs a first direct current voltage to the voltage protection energy discharge circuit.

[0031] In an implementation manner, the voltage protection energy discharge circuit includes a zener diode, a field effect tube, a power resistor, a first voltage dividing resistor, a second voltage dividing resistor and a current limiting resistor,

[0032] A cathode of the zener diode is connected with an output end of the rectification filter circuit, an anode of the zener diode is connected with a first end of the first voltage dividing resistor, a second end of the first voltage dividing resistor is connected with a first end of the second voltage dividing resistor, a second end of the second voltage dividing resistor is grounded, and the zener diode is turned on when the first direct current voltage exceeds a breakdown voltage of the zener diode.

[0033] A first end of the power resistor is connected with the output end of the rectification filter circuit, a source of the field effect tube is connected with a second end of the power resistor, a gate of the field effect tube is connected with a first end of the current limiting resistor, a drain of the field effect tube is grounded, and a second end of the current limiting resistor is connected with the second end of the first voltage dividing resistor, the field effect tube is turned on when the zener diode is turned on, and the power resistor consumes the first direct current voltage.

[0034] In an implementation manner, the flow meter body is a gas meter.

[0035] The application provides a flowmeter with an inductive power taking device, which comprises an inductive power taking device and a flowmeter body. The inductive power taking device comprises an electromagnetic induction device, a protection circuit, a rectification filter circuit, a voltage protection energy discharge circuit and a voltage conversion circuit connected in sequence. The electromagnetic induction device is used for being nested on a high-voltage bus and generating a first alternating voltage based on the electromagnetic induction principle. The protection circuit is used for limiting the first alternating voltage in a first voltage range when a surge current occurs on the high-voltage bus, so as to ensure that the circuit is not impacted by transient overvoltage. The rectification filter circuit is used for converting the first alternating voltage in the first voltage range into a first direct current voltage, and the first direct current voltage may contain transient overvoltage which is missed by the protection circuit. The voltage protection energy discharge circuit is used for consuming the transient overvoltage in the first direct current voltage and limiting the first direct current voltage in a second voltage range. The voltage conversion circuit is used for reducing the first direct current voltage in the second voltage range to a third voltage range and generating an output voltage, so that the output voltage meets the power demand of the flowmeter body and stably supplies power to the flowmeter body. The flowmeter does not need to frequently replace batteries, and the inductive power taking device can obtain a safe current from the high-voltage bus for a long time, thereby improving the safety and continuity of the flowmeter. BRIEF DESCRIPTION OF DRAWINGS

[0036] The drawings incorporated into the specification and forming a part thereof, illustrate preferred embodiments and, together with the description, serve to explain the principles of the application. It is to be expressly understood that the drawings are some embodiments and that they are, therefore, to be interpreted not in an absolutely literal and / or exclusive sense.

[0037] Figure 1 A structural schematic diagram of a flowmeter with an inductive power taking device provided by the application;

[0038] Figure 2 A structural schematic diagram of a through-type current transformer provided by the application;

[0039] Figure 3 A structural schematic diagram of another flowmeter with an inductive power taking device provided by the application;

[0040] Figure 4 A schematic diagram of a voltage protection energy discharge circuit provided by the application.

[0041] Explanation of reference signs:

[0042] 10 - inductive power taking device; 20 - flowmeter body; 30 - high-voltage bus; 40 - energy storage device; 50 - power supply switching circuit;

[0043] 101 - electromagnetic induction device; 102 - protection circuit; 103 - rectification filter circuit; 104 - voltage protection energy discharge circuit; 105 - voltage conversion circuit;

[0044] 1011 - inductive core; 1012 - induction coil;

[0045] 1021 - flat wave reactance; 1022 - surge protector;

[0046] 1031 - rectification circuit; 1032 - filter circuit;

[0047] 1041 - voltage stabilizing diode; 1042 - field effect transistor; 1043 - power resistor; 1044 - first voltage dividing resistor; 1045 - second voltage dividing resistor; 1046 - current limiting resistor;

[0048] 201 - electronic meter; 202 - flow metering device;

[0049] 2011 - control unit.

[0050] The above-described embodiments have been shown by the accompanying drawings, and will be described in more detail hereinafter. The accompanying drawings and the written description are not to be understood as limiting the scope of the present application in any way, but are merely constructed to explain the concept of the present application to one of ordinary skill in the art by referring to a particular embodiment. DETAILED DESCRIPTION

[0051] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The following description is made with reference to the accompanying drawings in which like reference numerals refer to like elements, and the term "exemplary" is used herein to mean "serving as an example, instance, or illustration." The following description is not intended to limit the scope of the present application in any way, but rather is intended to provide a description of the concepts of the present application in the context of particular embodiments. Accordingly, known methods, structures, devices, and

[0052] Second, it should be noted that in the description of the present application, the terms "inner", "outer" and the like indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings, which is merely for the convenience of description, and does not indicate or imply that the device or component must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0053] Furthermore, it should be noted that, in the description of the embodiments of this application, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0054] Smart flow meters (such as smart gas meters, smart water meters, and smart electricity meters, hereinafter referred to as flow meters) are usually powered by batteries. When the battery is damaged or the power is exhausted, the flow meter will not work properly and the battery needs to be replaced.

[0055] Battery lifespan is affected by various factors. For example, when the flow meter is used frequently or needs to communicate with external devices often, the battery will deplete more quickly. Alkaline batteries, for instance, experience a significant performance drop in low temperatures; if the flow meter operates in cold regions, the battery will be damaged more rapidly. A shorter battery life means more frequent battery replacements, leading to higher maintenance costs. Furthermore, replacing batteries is a complex process that requires consideration of battery and flow meter compatibility. For example, with gas meters, replacing the battery requires closing the valve, opening the small cover, and removing the sulfuric acid paper bag. Incorrect battery installation or the use of an incompatible battery will affect the normal operation of the gas meter.

[0056] To address the aforementioned technical problems, this application proposes a flowmeter with an inductive power extraction device. The flowmeter includes an inductive power extraction device and a flowmeter body. The inductive power extraction device comprises, in sequence, an electromagnetic induction device, a protection circuit, a rectifier and filter circuit, a voltage protection energy discharge circuit, and a voltage conversion circuit. Specifically, the electromagnetic induction device is nested within a high-voltage busbar and generates a first AC voltage based on the principle of electromagnetic induction; the protection circuit limits the first AC voltage to a first voltage range when a surge current occurs on the high-voltage busbar, ensuring the circuit is protected from transient overvoltages; the rectifier and filter circuit converts the first AC voltage within the first voltage range into a first DC voltage, which may contain transient overvoltages missed by the protection circuit; the voltage protection energy discharge circuit dissipates the transient overvoltages present in the first DC voltage, limiting the first DC voltage to a second voltage range; and the voltage conversion circuit reduces the first DC voltage within the second voltage range to a third voltage range, generating an output voltage that meets the power requirements of the flowmeter body and stably supplies power to the flowmeter body. This flow meter does not require frequent battery replacements and obtains a safe current from the high-voltage busbar through an inductive power supply device, thus improving the safety and sustainability of the flow meter.

[0057] In addition, in the case of abnormal situations such as short circuit or impact current of the circuit, the inductive power taking device can protect the circuit through the protection circuit and the voltage protection energy discharge circuit, so as to prevent the circuit or electronic device from being damaged, and further improve the safety.

[0058] When the flow meter with the inductive power taking device is installed, there is no need to additionally lay power supply lines, so that the purchase and construction cost of cables, pipes and other materials is reduced, and the installation cost is low; and the inductive power taking device has a relatively simple structure, and is installed at a position of power transmission line which is easy to observe and maintain, so that the daily maintenance workload is small, and there is no need to frequently install and replace the battery, thereby saving the maintenance cost.

[0059] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] Figure 1 A structure schematic diagram of a flow meter with an inductive power taking device is provided for the embodiments of the present application. The embodiments of the present application provide a flow meter with an inductive power taking device, referring to Figure 1 , the flow meter with the inductive power taking device 1 comprises an inductive power taking device 10 and a flow meter body 20.

[0061] The flow meter body 20 can be a gas flow meter, a liquid flow meter, an electric flow meter or other flow meters, and the type of the flow meter body 20 in the embodiment is not limited, for example, the flow meter body 20 can be a gas meter, a water meter or an electric meter.

[0062] The inductive power taking device 10 comprises an electromagnetic induction device 101, a protection circuit 102, a rectifier filter circuit 103, a voltage protection energy discharge circuit 104 and a voltage conversion circuit 105 connected in sequence.

[0063] In this embodiment, the electromagnetic induction device 101 is used to generate an induced AC voltage. The protection circuit 102 is connected in parallel with the electromagnetic induction device 101. When the generated induced AC voltage is too large, it consumes the excess AC voltage and outputs an AC voltage within the allowable range of the protection circuit 102, preventing transient overvoltages generated by the electromagnetic induction device 101 from impacting the circuit or electronic devices. The input of the rectifier-filter circuit 103 is the output of the protection circuit 102. It is used to rectify and filter the AC voltage output by the protection circuit 102 and output a smooth DC voltage. The input of the voltage protection energy discharge circuit 104 is the output of the rectifier-filter circuit 103. When the DC voltage output by the rectifier-filter circuit 103 is too large, it consumes the excess DC voltage and outputs a DC voltage within the allowable range of the voltage protection energy discharge circuit 104, preventing transient overvoltages missed by the protection circuit 102 from being converted into DC voltage by the rectifier-filter circuit 103 and impacting the circuit or electronic devices with excessive DC voltage. The input of the voltage conversion circuit 105 is the output of the voltage protection energy discharge circuit 104, which is used to reduce the DC voltage output by the voltage protection energy discharge circuit 104 to the voltage range available to the flow meter body 20.

[0064] The electromagnetic induction device 101 is used to be nested on the high-voltage bus 30 to generate a first AC voltage based on the principle of electromagnetic induction. The electromagnetic induction device 101 can be any device that generates an induced voltage based on electromagnetic induction; this embodiment does not limit its use.

[0065] For example, the electromagnetic induction device 101 can be a through-type current transformer. Figure 2 A schematic diagram of the structure of the through-hole current transformer provided in the application embodiment is shown below. Figure 2 As shown, the through-core current transformer includes an inductive core 1011 and an induction coil 1012. The induction coil 1012 is wound around the inductive core 1011, and the high-voltage bus 30 passes through the middle of the inductive core 1011. When alternating current flows through the high-voltage bus 30, the induction coil 1012 will induce the magnetic field generated by the current in the high-voltage bus 30, thereby generating an induced alternating voltage (i.e., the first alternating voltage).

[0066] The electromagnetic induction device 101 can also be an induction coil 1012 directly wound on the high-voltage bus 30, or other devices that can sense the magnetic field generated by the current in the high-voltage bus 30 and generate an induced AC voltage.

[0067] It should be noted that the high-voltage bus 30 can be a power line of a residential building, an office building, or other places where the flow meter 1 is installed, and the present embodiment does not limit this. For example, the high-voltage bus 30 can be a power line connected to a public area lighting lamp or a public appliance, to ensure that the high-voltage bus 30 is often in an electrified state, so that the electromagnetic induction device 101 can induce a first alternating voltage.

[0068] In the present embodiment, the electromagnetic induction device is used to take power, which, compared with the prior art of using a battery to supply power, does not need to frequently replace the battery, avoids user battery installation errors or battery incompatibility, and thus optimizes the user's use experience.

[0069] In the present embodiment, after the electromagnetic induction device 101 induces a first alternating voltage, the first alternating voltage is output to the protection circuit 102, and the protection circuit 102 receives the first alternating voltage and processes the first alternating voltage.

[0070] The protection circuit 102 is configured to limit the first alternating voltage induced by the electromagnetic induction device 101 to be within a first voltage range when a surge current occurs in the high-voltage bus 30, and output a second alternating voltage within the first voltage range to the rectification and filtering circuit 103. Limiting the first alternating voltage to be within the first range prevents transient overvoltage generated by the electromagnetic induction device 101 from impacting the circuit or electronic device.

[0071] When the high-voltage bus 30 is struck by lightning or instantaneously short-circuited due to other reasons, the high-voltage bus 30 will generate a surge current, thereby causing the electromagnetic induction device 101 to generate a transient overvoltage. At this time, the protection circuit 102 provides a short-circuit path to guide excess electrical energy to the ground, thereby protecting the circuit and electronic device from the impact of transient overvoltage or surge current.

[0072] When the high-voltage bus 30 does not have a surge current, the protection circuit 102 does not work and does not consume or process the first alternating voltage, that is, the second alternating voltage output by the protection circuit 102 to the rectification and filtering circuit 103 is the first alternating voltage itself.

[0073] The protection circuit 102 can be any circuit that provides a short-circuit path to consume power when a transient overvoltage is received, and the present embodiment is not limited in this regard. For example, the protection circuit 102 can be a circuit containing electronic devices such as a smoothing reactor (i.e., an inductor), a voltage-dependent resistor, and a gas discharge tube. The smoothing reactor can generate a reverse voltage opposite to the transient overvoltage, thereby limiting the rate of change of current and mitigating the impact of the inrush current. When the voltage input to the protection circuit 102 exceeds the voltage threshold corresponding to the voltage-dependent resistor, the voltage-dependent resistor is turned on, forming a short-circuit path, so that the protection circuit 102 can direct the inrush current to the ground. When the voltage input to the protection circuit 102 exceeds the operating voltage of the gas discharge tube, the gas discharge tube discharges, forming a low-impedance path, and directs the transient overvoltage or inrush current to the ground.

[0074] It should be noted that different protection circuits 102 contain different electronic devices and circuit structures, and consume different amounts of power, i.e., the protection circuit 102 consumes different degrees of the first alternating voltage when the inrush current occurs in the high-voltage bus 30, and the corresponding first voltage range is also different. In actual applications, different protection circuits 102 can be selected according to the needs of the first voltage range to limit the first alternating voltage within the required voltage range.

[0075] In the present embodiment, the second alternating voltage within the first voltage range output by the protection circuit 102 is input to the rectifier filter circuit 103, which rectifies and filters the second alternating voltage. The rectifier filter circuit 103 converts the second alternating voltage into a first direct current voltage and outputs the first direct current voltage to the voltage protection energy discharge circuit 104. Converting the second alternating voltage into the first direct current voltage allows the alternating current power generated by the electromagnetic induction device 101 to be converted into direct current power that can stably power the flowmeter body 20.

[0076] The rectifier filter circuit 103 can be any circuit for converting alternating voltage to direct current voltage and filtering the direct current voltage, and the present embodiment is not limited in this regard.

[0077] For example, the rectification filter circuit 103 can be a half-wave rectification filter circuit, which includes a diode and a capacitor. The diode is used to rectify one half cycle of the second alternating voltage, convert the second alternating voltage into a direct voltage, and the direct voltage can contain an alternating voltage, which is manifested as fluctuation or pulsation, and needs to be filtered to obtain a smooth direct voltage; the capacitor is used to filter the converted direct voltage, and convert the converted direct voltage into a smooth direct voltage (i.e. the first direct voltage). The rectification filter circuit 103 can also be a bridge rectification filter circuit, which includes four diodes and a capacitor, and can rectify and filter both half cycles of the second alternating voltage, and convert the second alternating voltage into the first direct voltage.

[0078] In this embodiment, the first direct voltage output by the rectification filter circuit 103 is input to the voltage protection energy discharge circuit 104, and the voltage protection energy discharge circuit 104 performs voltage processing on the first direct voltage.

[0079] The voltage protection energy discharge circuit 104 is used to limit the first direct voltage within the second voltage range when the surge current occurs in the high-voltage bus 30, and output the second direct voltage within the second voltage range to the voltage conversion circuit 105.

[0080] In this embodiment, when the surge current occurs in the high-voltage bus 30, part of the transient overvoltage may not be consumed after the protection circuit 102 consumes the first alternating voltage output by the electromagnetic induction device 101, so that the second alternating voltage output by the protection circuit 102 contains an excessive alternating voltage, and then the first direct voltage output by the rectification filter circuit 103 contains an excessive direct voltage. When the first direct voltage contains an excessive direct voltage, the voltage protection energy discharge circuit can consume the first direct voltage, thereby protecting the circuit and the electronic device from the impact of the transient overvoltage or the surge current.

[0081] When the high-voltage bus 30 does not have a surge current or the first direct voltage does not contain an excessive direct voltage, the voltage protection energy discharge circuit 104 does not work, and does not consume or process the first direct voltage, i.e. the second direct voltage output by the voltage protection energy discharge circuit 104 to the rectification filter circuit 103 is the first direct voltage itself.

[0082] The voltage protection energy discharge circuit 104 is any circuit that provides a short-circuit path to consume electrical energy when receiving a transient overvoltage, and the present embodiment does not limit this. It should be noted that the voltage protection energy discharge circuit 104 can have the same circuit structure as the protection circuit 102, or can have a different circuit structure from the protection circuit 102.

[0083] It should be noted that different voltage protection energy discharge circuits 104 contain different electronic devices and circuit structures, and different electric energy can be consumed, that is, when the inrush current occurs in the high-voltage bus 30, the voltage protection energy discharge circuit 104 consumes the first alternating voltage to different degrees, and the corresponding second voltage range is also different. In actual application, different voltage protection energy discharge circuits 104 can be selected according to the needs of the second voltage range to limit the first direct current voltage within the required voltage range.

[0084] In this embodiment, the transient overvoltage generated by the inductor caused by the inrush current in the high-voltage bus is doubly protected by the protection circuit and the voltage protection energy discharge circuit. The protection circuit consumes alternating voltage, and the voltage protection energy discharge circuit protects the converted direct current voltage, so that the circuit is not impacted by transient overvoltage or transient large current, thereby being able to work stably.

[0085] In this embodiment, the second direct current voltage in the second voltage range output by the voltage protection energy discharge circuit 104 is input to the voltage conversion circuit 105, and the voltage conversion circuit 105 performs voltage processing on the second direct current voltage.

[0086] The voltage conversion circuit 105 reduces the second direct current voltage to a third voltage range to generate an output voltage. The second direct current voltage in the third range is the output voltage of the inductive power taking device 10. It should be noted that the third voltage range can be determined according to the allowable or safe voltage range of the flowmeter body 20. Different flowmeter bodies 20 correspond to different third voltage ranges, and different voltage conversion circuits 105 can be selected to reduce the second direct current voltage to different third voltage ranges.

[0087] In this embodiment, the output voltage generated by the voltage conversion circuit 105 is the final output voltage of the inductive power taking device 10, which can be used to power the flowmeter body 20.

[0088] In this embodiment, the second direct current voltage output by the rectifier filter circuit 103 increases with the increase of the current in the high-voltage bus 30. The current in the high-voltage bus 30 changes in a large range, so that the range of the second direct current voltage is also large, for example, the range of the second direct current voltage is [13V, 400V]. The voltage required by the flowmeter body 20 is low, so it is necessary to reduce the second direct current voltage to a low voltage range (i.e. a third voltage range). For example, the second direct current voltage in the range of [13V, 400V] is reduced to the range of [3V, 12V].

[0089] The voltage conversion circuit 105 can be any circuit for reducing a direct current voltage to a low voltage range, and the embodiment is not limited in this regard. For example, the voltage conversion circuit 105 can be a linear voltage regulator, a step-down converter or other step-down conversion circuit. The linear voltage regulator reduces the voltage by adjusting the voltage difference between the input voltage and the output voltage; the step-down converter converts the input higher direct current voltage to a lower direct current voltage by controlling the on-time of the switch in the circuit, adjusting the inductance and capacitance in the circuit.

[0090] It should be noted that different voltage conversion circuits 105 have different electronic devices and circuit structures, and can reduce the direct current voltage to different ranges, i.e., corresponding to different third voltage ranges. In actual application, different voltage conversion circuits 105 can be selected according to the needs of the third voltage range to reduce the second direct current voltage to a voltage range allowed or safe for the flowmeter body 20 to work.

[0091] The output voltage of the voltage conversion circuit 105 supplies power to the flowmeter body 20.

[0092] The output voltage of the voltage conversion circuit 105 is a direct current voltage in the third voltage range, which can meet the power demand of the flowmeter body 20 and stably supply power to the flowmeter body 20.

[0093] In the embodiment, the flowmeter includes an inductive power taking device and a flowmeter body. The inductive power taking device includes an electromagnetic induction device, a protection circuit, a rectification filter circuit, a voltage protection energy discharge circuit and a voltage conversion circuit connected in sequence. The electromagnetic induction device is used to be nested on a high-voltage bus and generate a first alternating current voltage based on the principle of electromagnetic induction. The protection circuit is used to limit the first alternating current voltage in a first voltage range when a surge current occurs in the high-voltage bus, so as to protect the circuit from the impact of transient overvoltage. The rectification filter circuit is used to convert the first alternating current voltage in the first voltage range into a first direct current voltage, which may have transient overvoltage that is missed by the protection circuit. The voltage protection energy discharge circuit is used to consume the transient overvoltage in the first direct current voltage and limit the first direct current voltage in a second voltage range. The voltage conversion circuit is used to reduce the first direct current voltage in the second voltage range to a third voltage range and generate an output voltage, so that the output voltage meets the power demand of the flowmeter body and stably supplies power to the flowmeter body. The flowmeter does not need to frequently replace the battery, and the inductive power taking device can obtain a safe current from the high-voltage bus for a long time, thereby improving the safety and persistence of the flowmeter.

[0094] In addition, in the case of abnormal conditions such as short circuit or impact current in the circuit, the inductive power taking device can protect the circuit through the protection circuit and the voltage protection energy discharge circuit, so as to prevent the circuit or electronic device from being damaged, thereby further improving the safety.

[0095] When installing a flow meter with an inductive power supply device, there is no need to lay additional power lines, which reduces the purchase and construction costs of materials such as cables and pipes, resulting in low installation costs. Furthermore, the inductive power supply device has a relatively simple structure and is installed in easily observable and maintainable locations such as power transmission lines, resulting in less daily maintenance workload and no need to replace batteries, thus saving maintenance costs.

[0096] It should be noted that the inductive power supply device is not limited by natural conditions such as weather and sunlight. It can achieve stable and efficient power supply in sunny, cloudy, rainy or snowy weather, and can adapt to changes in current within a certain range to provide a stable power supply for the flow meter body.

[0097] Figure 3 This is a schematic diagram of another flow meter with an inductive power extraction device provided in an embodiment of this application. In an optional implementation, refer to... Figure 3 The flow meter 2 with inductive power extraction device may also include an energy storage device 40.

[0098] In this embodiment, the output voltage of the voltage conversion circuit 105 can not only power the flow meter body 20, but also be used as a charging power source for the energy storage device 40 to charge the energy storage device 40.

[0099] The energy storage device 40 can be any type of electronic device capable of storing electrical energy, and this embodiment does not limit the type of energy storage device 40. For example, the energy storage device 40 can be an alkaline battery, a lithium battery, a nickel-metal hydride battery, or a supercapacitor, which has a short charging time, fast energy release, and long cycle life.

[0100] It should be noted that this embodiment does not limit the use of the energy storage device 40. For example, the energy storage device 40 can be used as a backup power source or supplementary power source for the flow meter body 20.

[0101] Optionally, refer to Figure 3 The flow rate 2 with inductive power extraction device may also include a power supply switching circuit 50.

[0102] The power supply switching circuit 50 includes an input terminal and an output terminal. The output terminal of the power supply switching circuit 50 is connected to the voltage input terminal of the flow meter body 20. The input terminal of the power supply switching circuit 50 is connected to the output terminal of the voltage conversion circuit 105 and the voltage output terminal of the energy storage device 40, respectively. The power supply switching circuit 50 is used to switch the power supply of the flow meter body 20.

[0103] The power supply switching circuit 50 is any circuit capable of receiving a control signal for power supply switching and switching power supply according to the control signal, which is not limited in the embodiment. For example, the power supply switching circuit 50 can be a relay switching circuit. When the relay switching circuit receives the control signal, the contacts of the relay will change the circuit connection state, so as to select different power supply. The power supply switching circuit 50 can also be a transistor switching circuit, which uses a transistor as a switching element and adjusts the conduction and shutdown of the transistor through the control signal, so as to realize the switching of different power supplies.

[0104] In the embodiment, when the power supply switching circuit 50 receives the control signal for power supply switching, the power supply of the flowmeter body 20 is switched to the inductive power pickup device 10 or the energy storage device 40.

[0105] The flowmeter body 20 includes an electronic watch head 201 and a flowmeter device 202, and the electronic watch head 201 includes a control unit 2011. The control unit 2011 is configured to control the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the energy storage device 40 when the output voltage of the voltage conversion circuit 105 is lower than the preset voltage threshold.

[0106] In the embodiment, the output voltage of the voltage conversion circuit 105 is positively correlated with the size of the current in the high-voltage bus 30, that is, the output voltage of the voltage conversion circuit 105 increases with the increase of the current in the high-voltage bus 30 and decreases with the decrease of the current in the high-voltage bus 30. That is, when there is no current or a small current in the high-voltage bus 30, the output voltage of the voltage conversion circuit 105 will be insufficient to maintain the normal operation of the flowmeter body 20, and the power supply of the flowmeter body 20 is switched to the energy storage device 40, so that the energy storage device 40 supplies power to the flowmeter body 20 to ensure the normal operation of the flowmeter body 20.

[0107] The control unit 2011 can monitor the output voltage of the voltage conversion circuit 105 in real time and compare the size of the output voltage of the voltage conversion circuit 105 with the preset voltage threshold.

[0108] When the output voltage of the voltage conversion circuit 105 is lower than the preset voltage threshold, the control unit 2011 sends a control signal for power supply switching to the power supply switching circuit 50, and the control signal instructs the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the energy storage device 40. The preset voltage threshold can be set according to the actual application, which is not limited in the embodiment.

[0109] When the output voltage of the voltage conversion circuit 105 is higher than or equal to the preset voltage threshold, the control unit 2011 sends a power supply switching control signal to the power supply switching circuit 50, and the control signal instructs the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the inductive power device 10.

[0110] The control unit 2011 is also used to switch the power supply of the flowmeter body 20 to the energy storage device 40 when the electronic meter 201 communicates with the outside.

[0111] In this embodiment, the electronic meter 201 can communicate with the outside wirelessly. For example, for a gas meter, the electronic meter 201 of the gas meter can use a wireless data transmission method such as NB (Narrowband Internet of Things), 4G (Fourth Generation Mobile Communication), 5G (Fifth Generation Mobile Communication), or LORA (Long Range Wide Area Network) to communicate wirelessly with a cloud monitoring system. When communicating wirelessly, the electronic meter 201 needs a larger current to transmit and receive data, and the gas meter needs a smaller current when not communicating wirelessly and transmitting and receiving data. The current used by the inductive power device 10 to power the flowmeter body 20 is usually small, which can meet the power demand of the gas meter when not communicating wirelessly, but cannot meet the power demand of the electronic meter 201 when communicating wirelessly. Therefore, when the electronic meter 201 communicates with the outside, the power supply of the flowmeter body 20 is switched to the energy storage device 40 to meet the power demand of the flowmeter body 20 when the electronic meter 201 communicates with the outside.

[0112] When the electronic meter 201 communicates with the outside, the control unit 2011 sends a power supply switching control signal to the power supply switching circuit 50, and the control signal instructs the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the energy storage device 40.

[0113] Taking a gas meter as an example, the electronic meter 201 of the gas meter reports gas data to a cloud monitoring system at regular intervals. Within a preset time period before the electronic meter 201 reports data, the control unit 2011 sends a power supply switching control signal to the power supply switching circuit 50 before the electronic meter 201 reports data, and the control signal instructs the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the energy storage device 40. The preset time period can be set according to actual application needs, which is not limited in this embodiment.

[0114] After the communication between the electronic meter 201 and the cloud monitoring system ends, the control unit 2011 sends a power supply switching control signal to the power supply switching circuit 50, and the control signal instructs the power supply switching circuit 50 to switch the power supply of the flowmeter body 20 to the induction power device 10.

[0115] In this embodiment, when the surge current is generated in the high-voltage bus 30, the electromagnetic induction device 101 generates a transient overvoltage, that is, a high-amplitude fluctuation or a spike suddenly appearing in the circuit in a very short time, which may cause damage to electrical equipment, shorten the service life, interfere with normal work, and even cause fire safety hazards.

[0116] The protection circuit 102 includes a surge protector 1022, which is used to limit the transient overvoltage to a first voltage range when the electromagnetic induction device 101 generates a transient overvoltage, and output a second alternating voltage in the first voltage range. The output of the surge protector 1022 is the output of the protection circuit 102, that is, the surge protector 1022 outputs the second alternating voltage in the first voltage range.

[0117] Optionally, the protection circuit 102 can further include a smoothing reactor 1021, which is connected in series with the electromagnetic induction device 101, and the smoothing reactor 1021 is used to share the transient overvoltage generated by the electromagnetic induction device 101 when the surge current is generated in the high-voltage bus 30.

[0118] The smoothing reactor 1021 can generate a reverse voltage opposite to the transient overvoltage, thereby limiting the rate of change of current and slowing down the impact of the surge current, playing a role of current limiting and voltage dividing, sharing a large part of the high voltage induced by the induction coil 1012, and limiting the transient large current output of the induction coil 1012, ensuring that the circuit can work normally when the surge current is generated in the high-voltage bus 30, and further enabling the induction power device 10 to supply power stably.

[0119] Further, the output of the smoothing reactor 1021 is connected to the input of the surge protector 1022, and the surge protector 1022 limits the output voltage of the smoothing reactor 1021 to the first voltage range when the transient overvoltage appears in the output of the smoothing reactor 1021, and outputs a second alternating voltage in the first voltage range. The output of the surge protector 1022 is the output of the protection circuit 102, that is, the surge protector 1022 outputs the second alternating voltage in the first voltage range.

[0120] In this embodiment, the flat wave reactor 1021 and the surge protector 1022 are connected in series. When a surge current occurs in the high-voltage bus 30, the flat wave reactor 1021 is used to divide the transient overvoltage and transient large current generated by the induction coil 1012 and limit the current, and when the flat wave reactor 1021 still outputs the transient overvoltage, the surge protector 1022 provides a short-circuit path to guide the transient large current to the ground and consume part of the voltage, thereby limiting the voltage of the surge protector 1022 within the first voltage range.

[0121] In this embodiment, the surge protector 1022 can be selected according to the actual application, and can be selected according to the demand for the first voltage range, which is not limited in this embodiment. For example, the surge protector 1022 can be a pressure-sensitive resistor, a gas discharge tube, or a silicon transient suppression diode, or a combination of a pressure-sensitive resistor, a gas discharge tube, and a silicon transient suppression diode.

[0122] In an optional embodiment, on the basis of any of the preceding embodiments, the rectifying and filtering circuit 103 includes a rectifying circuit 1031 and a filtering circuit 1032.

[0123] In this embodiment, the input end of the rectifying circuit 1031 is connected to the output end of the protection circuit 102, and the rectifying circuit 1031 converts the second alternating voltage into a third direct current voltage and outputs the third direct current voltage to the filtering circuit 1032.

[0124] In this embodiment, the rectifying circuit 1031 can be any circuit for converting alternating voltage into direct current voltage, which is not limited in this embodiment. For example, the rectifying circuit 1031 can be a half-wave rectifying circuit, a full-wave rectifying circuit, or a bidirectional rectifying circuit.

[0125] The output end of the filtering circuit 1032 is connected to the input end of the voltage protection energy discharge circuit 104, and the filtering circuit 1032 filters the third direct current voltage and outputs a first direct current voltage to the voltage protection energy discharge circuit 104.

[0126] The rectifying circuit 1031 rectifies the second alternating voltage output by the surge protector 1022 and outputs a third direct current voltage, which is usually pulsating. In order to obtain a smooth direct current voltage, the filtering circuit 1032 is also needed to smooth the direct current voltage, and the filtering circuit 1032 outputs a smooth first direct current voltage to ensure that the induction power taking device 10 can be stably powered.

[0127] In this embodiment, when a surge current occurs in the high-voltage bus 30, after the transient overvoltage generated by the induction coil 1012 is consumed by the flat wave reactor 1021 and the surge protector 1022, there may still be a transient overvoltage that is missed and converted into a first direct current voltage.

[0128] When there is a transient overvoltage in the first DC voltage output by the filtering circuit 1032, the voltage protection energy discharge circuit 104 is used to consume the first DC voltage, thereby protecting the circuit and electronic device from the impact of transient overvoltage or inrush current.

[0129] The voltage protection energy discharge circuit 104 limits the first DC voltage within a second voltage range, and the voltage conversion circuit 105 outputs a second DC voltage within the second voltage range. The voltage conversion circuit 105 reduces the second DC voltage to a third voltage range, generating an output voltage to power the flowmeter body 20 and the energy storage device 40.

[0130] The working principles of the voltage protection energy discharge circuit 104 and the voltage conversion circuit 105 can be referred to the related content in the foregoing embodiments, which will not be repeated here.

[0131] In the embodiment, in the case of insufficient current in the high-voltage bus or lack of power in the high-voltage bus, the power supply switching circuit switches the power supply of the flowmeter body to the energy storage device, so that the flowmeter body can always have stable power supply and will not be out of power due to problems of the inductive power taking device. When the electronic watch head of the flowmeter body needs to communicate with the outside and requires a larger current, the power supply switching circuit switches the power supply of the flowmeter body to the energy storage device, so that the electronic watch head of the flowmeter body can normally communicate with the outside, and the flowmeter body is provided with sufficient and stable power supply. Moreover, the electronic watch head of the flowmeter body adopts a high-performance control unit, and the power supply switching circuit adopts a high-performance circuit design, which can quickly respond to the change of the power supply in a short time, and realize stable power supply for the flowmeter body.

[0132] Figure 4 A schematic diagram of a voltage protection energy discharge circuit provided in the embodiment of the present application is shown in FIG. 10. In an alternative implementation, referring to FIG. 10, Figure 4 The voltage protection energy discharge circuit 104 includes a zener diode 1041, a field effect transistor 1042, a power resistor 1043, a first voltage dividing resistor 1044, a second voltage dividing resistor 1045, and a current limiting resistor 1046.

[0133] The cathode of the zener diode 1041 is connected to the output end of the rectifier filtering circuit 103 (indicated by "+" in the figure), and the anode of the zener diode 1041 is connected to the first end of the first voltage dividing resistor 1044. The second end of the first voltage dividing resistor 1044 is connected to the first end of the second voltage dividing resistor 1045, and the second end of the second voltage dividing resistor 1045 is grounded (indicated by "-" in the figure). When the first DC voltage exceeds the breakdown voltage of the zener diode, the zener diode 1041 is turned on. Figure 4 Figure 4

[0134] ​​When the first direct current voltage output by the rectifier filter circuit 103 exceeds the breakdown voltage of the voltage stabilizing diode 1041, the voltage stabilizing diode 1041 is turned on, so that the current can flow through the voltage stabilizing diode 1041, the first voltage dividing resistor 1044 and the second voltage dividing resistor 1045 to the ground, to avoid the impact of transient large current on the circuit. Among them, the first voltage dividing resistor 1044 and the second voltage dividing resistor 1045 are used to share the first direct current voltage, to ensure that the voltage stabilizing diode 1041 can work normally within its allowable voltage range, and avoid damage or failure to work normally due to excessive voltage.

[0135] The first end of the power resistor 1043 is connected to the output end of the rectifier filter circuit 103, the source of the field effect transistor 1042 is connected to the second end of the power resistor 1043, the gate of the field effect transistor 1042 is connected to the first end of the current limiting resistor 1046, the drain of the field effect transistor 1042 is grounded, and the second end of the current limiting resistor 1046 is connected to the second end of the first voltage dividing resistor 1044. When the voltage stabilizing diode 1041 is turned on, the field effect transistor 1042 is turned on, and the power resistor 1043 consumes the first direct current voltage.

[0136] When the voltage stabilizing diode 1041 is turned on, the current can also pass through the current limiting resistor 1046 to the gate of the field effect transistor 1042, so that the gate voltage is greater than the threshold voltage of the field effect transistor 1042, and the field effect transistor 1042 is turned on, thereby enabling the current to flow from the power resistor 1043, and the power resistor consumes the first direct current voltage. Among them, the current limiting resistor 1046 is used to reduce the current flowing through the gate of the field effect transistor 1042, to ensure that the field effect transistor 1042 can work normally within its allowable current range, and avoid damage or failure to work normally due to excessive current.

[0137] Among them, the field effect transistor 1042 can be any type of field effect transistor, and the present embodiment does not limit it, for example, the field effect transistor 1042 can be a metal oxide semiconductor field effect transistor, a junction field effect transistor or a silicon-based field effect transistor, etc.

[0138] In the present embodiment, when the first direct current voltage is too large, the voltage stabilizing diode is turned on, so that the excessive current can be guided to the ground to protect the circuit from the impact of excessive current; when the voltage stabilizing diode is turned on, the field effect transistor is also turned on, so that the power resistor can consume the excessive voltage to protect the circuit from the impact of excessive voltage.

[0139] Those skilled in the art, after considering the specification and practicing the technical solutions disclosed herein, will easily think of other embodiments of the present application.

[0140] Embodiments of the application are intended to cover any variations, uses, or adaptations of embodiments of the application following, in general, the principles of embodiments of the application and including such

[0141] The specification and examples are to be regarded in an illustrative manner and the true scope and spirit of embodiments of the application are indicated by the following claims.

[0142] It should be understood that the application is not limited to the precise construction and compositions described above and shown in the attached drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is indicated by the claims appended hereto.

Claims

1. A flow meter with an inductive power-generating device, characterized in that, include: Inductive power supply device and flow meter body; The inductive power extraction device includes an electromagnetic induction device, a protection circuit, a rectifier and filter circuit, a voltage protection energy discharge circuit, and a voltage conversion circuit connected in sequence. The electromagnetic induction device is used to be nested on the high-voltage busbar and generates a first AC voltage based on the principle of electromagnetic induction. The protection circuit is used to limit the first AC voltage generated by the electromagnetic induction device to a first voltage range when a surge current occurs on the high-voltage bus, and to output a second AC voltage within the first voltage range to the rectifier and filter circuit. The rectifier and filter circuit converts the second AC voltage into a first DC voltage and outputs the first DC voltage to the voltage protection energy discharge circuit. The voltage protection energy discharge circuit is used to limit the first DC voltage to a second voltage range when a surge current occurs on the high voltage bus, and output a second DC voltage within the second voltage range to the voltage conversion circuit. The voltage conversion circuit reduces the second DC voltage to a third voltage range to generate an output voltage. The output voltage of the voltage conversion circuit powers the flow meter body.

2. The flow meter according to claim 1, characterized in that, Also includes: Energy storage devices The output voltage of the voltage conversion circuit is used as the charging power for the energy storage device.

3. The flow meter according to claim 2, characterized in that, Also includes: The power supply switching circuit includes an input terminal and an output terminal. The output terminal of the power supply switching circuit is connected to the voltage input terminal of the flow meter body. The input terminal of the power supply switching circuit is connected to the output terminal of the voltage conversion circuit and the voltage output terminal of the energy storage device, respectively. The power supply switching circuit is used to switch the power supply to the flow meter body.

4. The flow meter according to claim 3, characterized in that, The flow meter body includes: an electronic meter head and a flow metering device, wherein the electronic meter head includes a control unit; The control unit is used to control the power supply switching circuit to switch the power supply of the flow meter body to the energy storage device when the output voltage of the voltage conversion circuit is lower than a preset voltage threshold.

5. The flow meter according to claim 4, characterized in that, The control unit is also used for: When the electronic meter head communicates with the outside, the power supply switching circuit controls the power supply of the flow meter body to the energy storage device. The energy storage device can be any one of an alkaline battery, a lithium battery, a nickel-metal hydride battery, or a supercapacitor.

6. The flow meter according to claim 1, characterized in that, The protection circuit includes a surge protector. The surge protector is used to limit the transient overvoltage generated by the electromagnetic induction device to the first voltage range when a surge current is generated on the high-voltage bus, and output a second AC voltage within the first voltage range.

7. The flow meter according to claim 6, characterized in that, The protection circuit includes a smoothing reactor, which is connected in series with the electromagnetic induction device. The output of the smoothing reactor is connected to the input of the surge protector. The smoothing reactor is used to share the transient overvoltage generated by the electromagnetic induction device when a surge current is generated on the high-voltage bus.

8. The flow meter according to claim 1, characterized in that, The rectifier-filter circuit includes a rectifier circuit and a filter circuit. The input terminal of the rectifier circuit is connected to the output terminal of the protection circuit. The rectifier circuit converts the second AC voltage into a third DC voltage and outputs the third DC voltage to the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the voltage protection energy discharge circuit. The filter circuit filters the third DC voltage and outputs the first DC voltage to the voltage protection energy discharge circuit.

9. The flow meter according to claim 1, characterized in that, The voltage protection energy discharge circuit includes a Zener diode, a field-effect transistor, a power resistor, a first voltage divider resistor, a second voltage divider resistor, and a current-limiting resistor. The cathode of the Zener diode is connected to the output terminal of the rectifier filter circuit, the anode of the Zener diode is connected to the first terminal of the first voltage divider resistor, the second terminal of the first voltage divider resistor is connected to the first terminal of the second voltage divider resistor, and the second terminal of the second voltage divider resistor is grounded. When the first DC voltage exceeds the breakdown voltage of the Zener diode, the Zener diode conducts. The first end of the power resistor is connected to the output end of the rectifier filter circuit, the source of the field-effect transistor is connected to the second end of the power resistor, the gate of the field-effect transistor is connected to the first end of the current-limiting resistor, the drain of the field-effect transistor is grounded, and the second end of the current-limiting resistor is connected to the second end of the first voltage divider resistor. When the Zener diode is turned on, the field-effect transistor is turned on, and the power resistor consumes the first DC voltage.

10. The flow meter according to any one of claims 1-9, characterized in that, The flow meter body is a gas meter.

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