Portable resonance eliminator parameter measuring instrument

Abstract

The utility model discloses a portable resonance eliminator parameter measuring instrument, which comprises a lithium battery power supply, a digital adjustable alternating current power supply module, a boosting transformer, a relay and an ARM control chip, a direct current power supply is connected with the digital adjustable alternating current power supply module for driving, and the digital adjustable alternating current power supply is connected with the boosting transformer and then connected with the relay. The relay is connected with the detected resonance eliminator for detection, the ARM control chip is connected with the relay and used for controlling the relay to be connected or disconnected, one end of the relay is connected with the voltage transformer and the current transformer, and the voltage transformer and the current transformer are connected with the ARM control chip. Particularly, the output end of the boosting transformer is connected with the normally open contact of the relay, and the normally closed contact of the relay is connected in series with the resistor and then connected with the protection ground, so that residual voltage at two ends of the detected resonance eliminator flows into the protection ground through the resistor, thereby protecting personal safety. Set parameters can be input through the display touch screen, real-time data of the digital adjustable alternating current power supply can be inquired, and man-machine conversation can be carried out.

Description

Technical Field

[0001] The utility model relates to the technical field of harmonic elimination detection, in particular to a portable harmonic elimination parameter measuring instrument. Background Art

[0002] A harmonic eliminator is a reactive power compensation device used in power systems to reduce or eliminate harmonics and filter reactive power in power systems. Harmonics refer to voltage and current waveforms whose frequencies are integer multiples of the fundamental frequency in power systems. They can cause power loss, equipment failure, interference with other equipment, and other problems in power systems. Therefore, the use of harmonic eliminators can effectively improve the reliability and stability of power systems.

[0003] A nonlinear resistor detuning damping device (referred to as "detuning device") installed between the neutral point of the primary winding of a 6kV~35kV voltage transformer (referred to as "PT") and the ground, uses ultra-fine SiC particles as the substrate, is pressed into a high-density rectangular or round cake-shaped blank by a large-tonnage press, and is sintered at a high temperature of thousands of degrees under the action of reducing gas. The detuning device can achieve the purpose of suppressing inrush current and PT ferromagnetic resonance, but at the same time does not affect the normal operation of the voltage transformer.

[0004] Usually, the detuning device parameter tester is mainly used for factory tests and field performance tests of the detuning device to verify whether the detuning device is qualified, including checking its power frequency current and voltage parameters. During the use of the detuning device on site, its parameters will change due to the absorption of moisture in the air or the passage of a large current. If the parameter change exceeds the range in the manufacturer's technical parameter table, it should be repaired or replaced. However, the detuning device parameter tester needs to be connected to an adjustable AC power supply for testing, which makes it inconvenient to carry out. Therefore, a portable detuning device parameter measuring instrument is urgently needed. Utility Model Content

[0005] The content of this utility model is used to introduce the concepts in a brief form, which will be described in detail in the following specific implementation. The content of this utility model is not intended to identify the key features or essential features of the technical solution claimed for protection, nor is it intended to limit the scope of the technical solution claimed for protection.

[0006] In view of the problems and shortcomings in the prior art, the utility model provides a portable harmonic elimination parameter measuring instrument, which uses a lithium battery power output connection to drive a digital adjustable AC power module to output AC voltage, outputs high-voltage AC power after being stepped up by a step-up transformer, and combines an ARM control chip to control the conduction or cutoff of a relay. After being turned on, the current transformer and voltage transformer are used to complete the detection of the harmonic elimination device under test, so as to solve the problems raised in the above background technology.

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: including a lithium battery power supply, a digitally adjustable AC power supply module, a step-up transformer, a relay and an ARM control chip, the DC power supply is electrically connected to the digitally adjustable AC power supply module for driving, the digitally adjustable AC power supply is electrically connected to the step-up transformer and then electrically connected to the relay, the ARM control chip is electrically connected to the relay for controlling the conduction or disconnection thereof, one end of the relay is electrically connected to a voltage transformer and a current transformer, and the voltage transformer and the current transformer are electrically connected to the ARM control chip, and the relay is electrically connected to the measured detuning device for detection.

[0008] Preferably, the normally open contact of the relay is electrically connected to the output end of the step-up transformer, and the normally closed contact of the relay is connected in series with a resistor and then connected to the protective ground. The output end of the step-up transformer is electrically connected to the normally open contact of the relay, and the normally closed contact of the relay is connected in series with resistors R7 and R8 and then connected to the protective ground. The residual voltage at both ends of the measured detuning device can flow into the protective ground through resistors R7 and R8 respectively, thereby protecting the personal safety of the detection personnel.

[0009] Preferably, the current transformer is connected in parallel with a resistor and then electrically connected to the output end of the voltage regulator. One end of the current transformer is connected in parallel with a resistor R5 and then electrically connected to the output end of the voltage regulator. The voltage regulator is a device that stabilizes the output voltage, that is, stabilizes the power supply voltage that fluctuates greatly and does not meet the requirements of the electrical equipment within its set value range, so that various circuits or electrical equipment can work normally under the rated working voltage. Therefore, the current transformer can work stably, improving the stability and safety during use.

[0010] Preferably, a Darlington tube consisting of two triodes is connected in series between the ARM control chip and the relay. The Darlington tube can amplify very small signals in a highly sensitive amplifier circuit, so it has a very high amplification factor, so that the ARM control chip can accurately control the conduction or disconnection of the relay.

[0011] Preferably, the ARM control chip is communicatively connected to the digital adjustable AC power module. The ARM control chip is communicatively connected to the digital adjustable AC power module via a serial UART. When in use, the ARM control chip learns the current gear selected by the user via the serial UART, and the ARM control chip sends an AC output voltage command corresponding to the gear to the digital adjustable AC power module via the serial UART.

[0012] Preferably, the ARM control chip is also connected to the display touch screen. The ARM control chip is connected to the touch display screen via the serial UART communication. When in use, the display touch screen can communicate with the ARM control chip via the serial UART, and the operator can input the parameters to be viewed or set through the display touch screen, query or modify the real-time data of the digital adjustable AC power supply, and conduct human-computer dialogue. At the same time, the voltage and current of the tested detuning device are also displayed on the display touch screen for the user to analyze and judge.

[0013] Preferably, the relay adopts a magnetic latching relay with double sets of switching contacts. The magnetic latching relay is an automatic switch that automatically connects and disconnects the circuit. The normally closed or normally open state of the magnetic latching relay completely depends on the action of the permanent magnet, and the switching state conversion is initiated by a pulse electrical signal of a certain width. It has the advantages of power saving, stable performance, small size and large carrying capacity. The double sets of switching contacts can control two circuits at the same time through double contact points, thereby controlling more electrical equipment.

[0014] Compared with the prior art, the beneficial effects provided by the utility model are:

[0015] The test instrument of the utility model can detect the corresponding voltage peak value or effective value of the harmonic elimination device when the current peak range is 0.3mA~10mA and various parameters are compared. The DC power supply output by the lithium battery drives the digital adjustable AC power supply module to output an adjustable AC power supply, and the output AC power supply outputs a high-voltage AC power supply via a step-up transformer. The output high-voltage AC power supply is connected to the normally open contact of the relay, and the common end of the relay is connected to the current transformer and the voltage transformer, and then the harmonic elimination device to be tested is connected to the common end of the relay, and the high-voltage current and voltage applied to the harmonic elimination device to be tested can be measured. The coil of the relay is connected to the ARM control chip, and the conduction or disconnection of the relay can be controlled by the ARM control chip. At the same time, the ARM control chip also connects the display touch screen and the digital adjustable AC power supply through the serial port UART communication, and the operator can input the parameters to be viewed or set through the touch screen, query or modify the real-time data of the digital adjustable AC power supply, and conduct human-computer dialogue. The lithium battery power supply can improve the portability of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a block diagram of the connection principle of the portable detuning device parameter measuring instrument of the utility model;

[0017] Figure 2 The utility model is a connection circuit diagram of a portable detuning device parameter measuring instrument. DETAILED DESCRIPTION

[0018] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for exemplary purposes and are not intended to limit the scope of protection of the present disclosure.

[0019] It should also be noted that, for ease of description, only the parts related to the invention are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other. Example

[0020] This embodiment provides a portable detuning parameter measuring instrument, referring to Figure 1 As shown, it includes an ARM control chip, a lithium battery power supply, a digital adjustable power module, a step-up transformer, a relay, a voltage transformer and a current transformer. The DC power supply is electrically connected to the digital adjustable AC power supply to power it, the digital adjustable AC power module is electrically connected to the step-up transformer, the step-up transformer is electrically connected to the relay and then connected to the measured detuning device. The ARM control chip is electrically connected to the relay to control it, and one end of the relay is electrically connected to the ARM control chip through the voltage transformer and the current transformer respectively. The voltage transformer and the current transformer are used to realize analog-to-digital conversion through the ADC analog-to-digital conversion module of the ARM control chip peripheral, that is, to convert the analog signal in the circuit into a digital signal that can be recognized by the ARM control chip, so as to realize the reading of the measured parameters of the measured detuning device. The lithium battery power supply is a 12V lithium battery module, and the lithium battery has the characteristics of large capacity, light weight and small size, so it can improve the portability of the detuning device parameter measuring instrument of the utility model. The relay adopts a magnetic latching relay, which has the advantages of power saving, stable performance, small size and large carrying capacity.

[0021] Reference Figure 2As shown, the power supply terminal and ground terminal of the lithium battery power supply BT1 are electrically connected to the input 12V terminal and the ground GND terminal of the digital adjustable AC power supply M1, the ACL live wire terminal and the ACN neutral wire terminal of the digital adjustable AC power supply M1 are electrically connected to the two input terminals of the transformer T1, the two input terminals of the transformer T1 are electrically connected to the two normally open contacts of the relay K1, and the two common control terminals of the relay K1 are electrically connected to the measured detuning device XXQ1. One of the common control terminals of the relay K1 is connected in series with the current transformer CT1, and the current transformer CT1 is connected in parallel with the resistor R5 and then electrically connected to the output terminal of the voltage regulator VR1, and then one end of the resistor R5 is electrically connected to the analog-to-digital conversion terminal ADC2 of the ARM control chip. The two normally closed contacts of the relay K1 are connected in series with the resistor R7 and the resistor R8 respectively and then grounded, and the resistor R7 and the resistor R8 are connected in parallel. One output end of transformer T1 is connected in series with resistor R1, resistor R2, voltage transformer T1, resistor R4 and resistor R3, and then electrically connected to the other output end of voltage transformer T2. The other end of voltage transformer T2 is electrically connected to analog-to-digital conversion section AD1 of ARM control chip U1. GPIO1 end of ARM control chip is connected in series with resistor R6, transistor Q2 and transistor Q1, and then electrically connected to the coil of relay K1, and the coil of relay K1 is electrically connected to DC 12V.

[0022] Specifically, the digital adjustable AC power supply M1 adopts the Shidu 35~250V digital adjustable power supply module, which is used to output adjustable AC power to the step-up transformer. Transformer T1 adopts a 1:10 high-voltage step-up transformer, which is used to convert a low-value alternating voltage into another higher-value alternating voltage of the same frequency. For example, if the input is 10V, the output is 100V. Resistors R1, R2, R3, and R4 use 470kΩ2W current-limiting resistors to limit the current in the branch to prevent excessive current from burning out the components in series. Resistor R5 is a current sampling resistor, resistor R6 is a current limiting resistor, and resistor R7 uses a high-voltage release resistor.

[0023] Relay K1 uses two sets of conversion contact relays. The contactor coil of the main power supply goes through the normally open contact of the relay, and the contactor coil of the backup power supply goes through the normally closed contact of the relay. When the main line is powered on, the normally open contact is closed, the main line is turned on, the normally closed contact is disconnected, and the backup power supply does not work. When the main line is powered off, the relay is also powered off. The normally open contact returns to the initial disconnected state, the main line is disconnected, and the contactor of the backup circuit starts working through the normally closed contact of the relay. The current transformer CT1 uses a through-type current transformer, which is used for measurement of low-voltage systems and energy metering. The lithium battery power supply BT1 uses a 12V / 2.5Ah lithium battery, which is easy to use and carry, and is used to power the digital adjustable AC power supply M1. The voltage transformer T2 uses a 2mA:2mA voltage transformer, which is used to power measuring instruments and relay protection devices, to measure the voltage, power and energy of the line, or to protect the equipment and transformers in the line when a line fault occurs.

[0024] Transistors Q1 and Q2 are NPN transistors, and NPN transistor Q1 and NPN transistor Q2 form a Darlington tube. The Darlington tube is two transistors connected together, and the polarity is only recognized by the front transistor. In the utility model, the collector of transistor Q2 is connected to the base of transistor Q1, and the emitters of transistor Q1 and transistor Q2 are both grounded. The usage of the Darlington tube is the same as that of the transistor, but the amplification factor is the product of the amplification factors of the two transistors. The Darlington tube can amplify very small signals in a highly sensitive amplifier circuit, so it is characterized by a very high amplification factor. The voltage regulator VR1 adopts a three-terminal voltage regulator, and the three-terminal voltage regulator VR1 is used to output a stable voltage to the current transformer, so that the current transformer can work stably and improve the stability and safety during use.

[0025] The ARM control chip U1 also connects the display touch screen M2 and the digital adjustable AC power supply M1 through the serial port UART communication. The display touch screen M2 uses an LCD touch screen. The receiving end RXD2 and the transmitting end TXD2 of the ARM control chip U1 are connected to the TXD transmitting end and the RXD receiving end of the display touch screen M2. The receiving end RXD1 and the transmitting end TXD1 of the ARM control chip U1 are connected to the TXD transmitting end and the RXD receiving end of the digital adjustable AC power supply M1. The display touch screen M2 can communicate with the ARM control chip U1 through the UART serial port. The operator can input the parameters to be viewed or set through the touch screen, query or modify the real-time data of the digital adjustable AC power supply, and conduct human-computer dialogue.

[0026] Method of using the utility model

[0027] According to the current corresponding to the detuning parameters tested by the user, select the appropriate gear on the LCD screen M2, which are 0.3mA, 0.5mA, 1mA, 3mA, 5mA, and 10mA. The ARM control chip will send the TXD2 terminal and receive the RXD2 terminal through the serial port to learn the current gear selected by the user. The ARM control chip sends the TXD1 terminal and receives the RXD1 terminal through the serial port to send the AC output voltage command corresponding to the gear to the digital adjustable AC power supply module M1.

[0028] The AC voltage output by the digital adjustable AC power module M1 can be boosted by the 1:10 step-up transformer T1 to output high-voltage AC power. The output high-voltage AC power is connected to two normally open contacts of two sets of switching contact relays K1. One end of the relay coil is connected to the 12V DC power supply, and the other end is connected to the collector of the Darlington transistor Q2. The base of the transistor Q2 is controlled by the collector of the transistor Q1, and the base of the transistor Q1 is controlled by the current limiting resistor R6 and the GPIO1 input / output port of the ARM control chip.

[0029] When the GPIO1 port outputs a high level, after passing through the current limiting resistor R6, the voltage at the base of the transistor Q1 is 0.7V. At this time, the transistor Q1 is turned on, and the transistor Q2 is also turned on. Since one end of the relay K1 coil is connected to the DC 12V and the other end is connected to the collector of the transistor Q1, the relay K1 coil is energized and the high-voltage AC power supply is output. When the GPIO1 port of the ARM control chip outputs a low level, the base voltage of the transistor Q1 is low, the transistor Q1 is turned off, and the transistor Q2 is turned off at the same time. The relay K1 coil has no path, the relay K1 is released, the high-voltage AC power supply output is open, and the output ends of its step-up transformer T1 are respectively connected to the normally closed contacts of the relay K1.

[0030] The output high voltage is measured by a 2mA:2mA voltage transformer, and the current is measured by a through-type current transformer. The ARM control chip ADC analog-to-digital conversion peripheral reads the voltage of the AC high-voltage power supply from the voltage transformer, and the ARM control chip ADC analog-to-digital conversion reads the output current of the AC high-voltage power supply from the current transformer, thereby measuring the high-voltage current and voltage applied to the measured detuning device. The high-voltage AC power supply signal ARM control chip automatically adjusts the AC output voltage of the digital adjustable power supply through the serial port TXD1 terminal and the receiving RXD1 terminal according to the gear of the measured detuning device current, thereby adjusting the output current to meet the measurement requirements of the detuning device. At the same time, the voltage and current of the measured detuning device are displayed on the LCD touch screen for users to analyze and judge. Resistors R7 and R8 are high-voltage release resistors. When the test is completed, the residual voltage at both ends of the measured detuning device will flow into the protection ground through resistors R7 and R8 respectively, thereby protecting the personal safety of the detection personnel.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] In addition, in the present utility model, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can make the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0033] The above are only preferred embodiments of the present invention, and the present invention may also have other embodiments. For those skilled in the art, the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A portable detuning parameter measuring instrument, characterized in that: It includes a DC power supply, a digitally adjustable AC power supply module, a step-up transformer, a relay and an ARM control chip. The DC power supply is electrically connected to the digitally adjustable AC power supply module for driving. The digitally adjustable AC power supply is electrically connected to the step-up transformer and then electrically connected to the relay. The ARM control chip is electrically connected to the relay for controlling the on or off of the relay. One end of the relay is electrically connected to a voltage transformer and a current transformer, and the voltage transformer and the current transformer are electrically connected to the ARM control chip. The relay is electrically connected to the measured detuning device for detection.

2. A portable detuning device parameter measuring instrument according to claim 1, characterized in that: The normally open contact of the relay is electrically connected to the output end of the step-up transformer, and the normally closed contact of the relay is connected in series with a resistor and then connected to a protective ground.

3. A portable detuning parameter measuring instrument according to claim 1, characterized in that: The current transformer is electrically connected to the output end of the voltage regulator after being connected in parallel with the resistor.

4. A portable detuning parameter measuring instrument according to claim 1, characterized in that: A Darlington transistor consisting of two triodes is connected in series between the ARM control chip and the relay.

5. A portable detuning device parameter measuring instrument according to claim 1, characterized in that: The ARM control chip is communicatively connected with the digital adjustable AC power supply module.

6. A portable detuning parameter measuring instrument according to claim 5, characterized in that: The ARM control chip is also connected to the display touch screen for communication.

7. A portable detuning device parameter measuring instrument according to claim 2, characterized in that: The relay is a magnetic latching relay with double sets of switching contacts.

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