Ultrahigh voltage power frequency withstand voltage detection device

Abstract

The utility model belongs to the technical field of power systems, and particularly relates to an ultra-high voltage power frequency withstand voltage detection device, which comprises a power supply module with one output end connected with a load circuit; the detection circuit is connected with the power supply module, the detection circuit comprises a voltage regulation circuit and a control circuit, and the voltage regulation circuit and the control circuit are connected with the power supply module in parallel; and the protection circuit is connected in the control circuit in series, and when the current of the detection device is abnormal, the protection circuit starts protection and cuts off a power supply. The ultrahigh-voltage power-frequency withstand voltage detection device provided by the utility model avoids potential safety hazards and economic loss caused by an overheating phenomenon of a circuit due to overcurrent.

Description

Technical Field

[0001] This utility model belongs to the technical field of power systems, specifically relating to an ultra-high voltage power frequency withstand voltage testing device. Background Technology

[0002] The ultra-high voltage power frequency withstand voltage test device is a specialized device used to test the insulation performance and withstand voltage capability of electrical equipment and products under ultra-high voltage conditions (this device is a withstand voltage test device for products under long-term ultra-high voltage conditions). Due to its portability, high efficiency, and safety, it is widely used in the power, electronics, and communications fields, electrical manufacturing departments, power operation departments, research institutions, and universities.

[0003] However, in this circuit, when a large current flows through the circuit, a lot of heat will be generated. Especially when the test object breaks down, the current in the circuit increases sharply. Since the magnitude of the current in the circuit cannot be detected, the circuit cannot be protected in time when an overcurrent occurs. That is, it cannot limit and cut off the fault current in time. After long-term operation, overcurrent or overheating will occur, which can easily lead to damage to key components such as electronic components and windings in the equipment, causing the entire circuit to fail, causing serious damage to the equipment, shortening the service life of the equipment, and even easily causing unsafe accidents such as circuit fires or explosions.

[0004] To address the aforementioned problems, this invention provides an ultra-high voltage power frequency withstand voltage testing device. Utility Model Content

[0005] One object of this invention is to solve at least the aforementioned problems or defects and to provide at least the advantages described below.

[0006] Another objective of this invention is to provide an ultra-high voltage power frequency withstand voltage testing device to avoid overheating of the circuit due to overcurrent, thereby preventing safety hazards and economic losses.

[0007] To achieve these objectives and other advantages according to this utility model, this utility model provides an ultra-high voltage power frequency withstand voltage testing device, comprising:

[0008] The power module has one output end connected to the load circuit; the power module is connected to the circuit via a circuit breaker, and after the circuit breaker, a power-side ammeter is connected to the load-side circuit.

[0009] A detection circuit is connected to the power module. The detection circuit includes a voltage regulation circuit and a control circuit, which are connected to the power module in parallel.

[0010] A protection circuit, connected in series in the control circuit, activates to cut off the power supply when the current of the detection device is abnormal.

[0011] Preferably, the voltage regulation circuit includes a first AC contactor and an autotransformer. One end of the first AC contactor is connected to the power module, and the other end is connected to one end of the autotransformer. The other end of the autotransformer is connected to the power module.

[0012] Preferably, the protection circuit includes two DC / AC selector switches, an overcurrent relay, a first alarm self-locking relay, a DC relay, an AC relay, and two second time-delay relays. One end of each of the DC relays and the AC relays is connected to the two DC / AC selector switches, and the other end is connected to the two second time-delay relays. The coil of the first alarm self-locking relay is connected to its normally closed contact, the overcurrent relay, the DC relay, the AC relay, and the two second time-delay relays.

[0013] Preferably, the control circuit includes a start-up circuit, a stop-up circuit, and an alarm circuit, with the start-up circuit, the stop-up circuit, and the alarm circuit connected to the power supply module at both ends; the coil of the first alarm self-locking relay is connected to the alarm circuit, and the DC / AC selector switch is connected to the start-up circuit.

[0014] Preferably, the start / stop circuit includes a start button, an autotransformer switch, a second time-delay relay, a second AC contactor, a second alarm self-locking relay, and a stop button. One end of the autotransformer switch is connected to the power module, and the other end is connected to one end of the start button. The other end of the start button is connected to the second time-delay relay and the second AC contactor. One end of the second AC contactor is connected to one end of the stop button, and the other end of the stop button is connected to the power module.

[0015] Preferably, the alarm circuit includes a timer button, a timer relay, and an alarm. One end of the timer button is connected to the power module, and the other end is connected to the contacts and coil of the timer relay. The timer relay is connected to the alarm.

[0016] Preferably, it also includes multiple indicator lights connected to the autotransformer switch.

[0017] This utility model has at least the following beneficial effects:

[0018] During ultra-high voltage power frequency withstand voltage testing, if the current in the circuit exceeds the maximum current that the test object can withstand, the current detection protection circuit connected in series with the testing device will activate protection, automatically cut off the equipment operation, and issue an audible and visual alarm. Therefore, it will not cause damage to internal components due to overheating caused by overcurrent due to long-term operation, which could lead to the paralysis of the entire circuit and cause equipment and personal injury. It can achieve efficient and long-term protection for the power frequency withstand voltage testing circuit. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the ultra-high voltage power frequency withstand voltage testing device described in this utility model;

[0020] Figure 2 This is a schematic diagram of the circuit principle of the ultra-high voltage power frequency withstand voltage testing device described in this utility model;

[0021] Among them, SA1-timer button, SA2-DC / AC selector switch, SB1-stop button, SB2-start button, KI1-overcurrent relay, KI2-DC relay, KI3-AC relay, KT-time relay, KT1-timer relay, KT2-delay relay, KM1-first AC contactor, KM2-second AC contactor, QA-autotransformer switch, KA-first alarm self-locking relay, KA1-second alarm self-locking relay, BK-autotransformer, EL1-zero position indicator, EL2-power indicator, EL3-run indicator. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0023] In this specification, when an element is referred to as "connected to or coupled to" another element or "located in another element," it may be "directly" connected to or coupled to the other element or "directly" located in the other element. Alternatively, it may be connected to or coupled to the other element or located in the other element with other elements interposed therebetween, unless it is specifically described as "directly coupled to or connected to" the other element or "directly located" in the other element. Furthermore, it should be understood that when an element is referred to as "on another element," "above another element," "below another element," or "under another element," it may be in "direct" contact with the other element or in contact with the other element through which other elements are interposed, unless it is specifically referred to as being in direct contact with the other element.

[0024] like Figure 1 As shown, this utility model provides an ultra-high voltage power frequency withstand voltage testing device, comprising:

[0025] The power module has one output end connected to the load circuit. Specifically, the power module is connected to the circuit via a double-pole circuit breaker (connected to the power supply via a double-pole air switch to provide the electrical energy required for the circuit to operate). After the circuit breaker, the live wire L1 and the overcurrent relay power-side ammeter (KI1) are connected to the load-side circuit. The current transformer is used to detect the current in the circuit.

[0026] A detection circuit is connected to the power module. The detection circuit includes a voltage regulation circuit and a control circuit, which are connected to the power module in parallel.

[0027] A protection circuit, connected in series in the control circuit, activates to cut off the power supply when the current of the detection device is abnormal. By adding a current detection protection loop to the detection circuit, efficient and long-term protection is achieved for the electronic components and circuits in the ultra-high voltage power frequency detection device.

[0028] like Figure 2 As shown, the voltage regulation circuit includes a first AC contactor KM1 and an autotransformer BK. One end of the first AC contactor KM1 is connected to the power supply module, and the other end is connected to one end of the autotransformer BK. The other end of the autotransformer BK is also connected to the power supply module. A live wire L1 is connected to the main contacts of KM1, and the autotransformer BK is connected after the main contacts of KM1. The autotransformer BK is used to regulate the output voltage. The main contacts of KM1 are used to connect and disconnect the autotransformer BK from the power supply. When the coil of contactor KM1 is energized, the main contacts close, connecting the autotransformer to the circuit, thereby regulating the circuit voltage; when the coil is de-energized, the main contacts open, cutting off the power supply to the autotransformer.

[0029] Specifically, the protection circuit includes two DC / AC selector switches SA2, an overcurrent relay KI1, a first alarm self-locking relay KA, a DC relay KI2, an AC relay KI3, and two second time-delay relays KT2. One end of the DC relay KI2 and the AC relay KI3 are respectively connected to the two DC / AC selector switches SA2, and the other end is respectively connected to the two second time-delay relays KT2. The coil of the first alarm self-locking relay KA is connected to its normally closed contact, the overcurrent relay KI1, the DC relay KI12, the AC relay KI3, and the two second time-delay relays KT2.

[0030] The coil of the first alarm self-locking relay KA is connected to a circuit consisting of multiple contacts SA2, KI1, KI2, KI3, and KT2. SA2 is a selector switch; rotating the switch allows switching between different DC and AC circuits. The coils of current relays KI1, KI2, and KI3 are connected in series in the circuit to detect the current in different branches. When the current reaches a set value, the corresponding contacts activate, thus affecting the state of the entire control circuit. When the branch current reaches the set value of current relay KI1, its internal contacts activate (normally open contacts close or normally closed contacts open), converting the current signal into a switching signal to control the operation of other circuit components, achieving overcurrent protection or logic control based on current magnitude.

[0031] Specifically, the control circuit includes a start-up circuit, a stop-up circuit, and an alarm circuit. The two ends of the start-up circuit, the stop-up circuit, and the alarm circuit are respectively connected to the power supply module. The coil of the first alarm self-locking relay KA is connected to the alarm circuit, and the DC / AC selector switch SA2 is connected to the start-up circuit.

[0032] Specifically, the start / stop circuit includes a start button SB2, an autotransformer switch QA, a second time delay relay KT2, a second AC contactor KM2, a second alarm self-locking relay KA1, and a stop button SB1. One end of the autotransformer switch QA is connected to the power module, and the other end is connected to one end of the start button SB2. The other end of the start button SB2 is connected to the second time delay relay KT2 and the second AC contactor KM2. One end of the second AC contactor KM2 is connected to one end of the stop button SB1, and the other end of the stop button SB1 is connected to the power module.

[0033] The start button SB2 and the stop button SB1 are connected in series, and then in parallel with the coil of the first contactor KM1. When the start button SB2 is pressed, the microswitch at the origin of the QA autotransformer prevents high voltage from occurring. When it is at zero position, the switch is closed. Combined with pressing the SB2 button, the coil of the first contactor KM1 is energized, the main contacts of KM1 close, and the circuit is connected. When the stop button SB1 is pressed, the coil of KM1 is de-energized, the main contacts open, and the circuit stops. The normally open auxiliary contact of contactor KM1 is connected in parallel with the start button SB2 to achieve a self-locking function, ensuring that the circuit remains connected after SB2 is released.

[0034] The coil of time relay KT2 is connected in series with the coil of contactor KM. KT2 is used to control the delayed action of other circuits. Working in conjunction with contactor KM, it achieves timing control of the circuit. For example, after contactor KM has been closed for a period of time, the contacts of KT2 actuate, potentially controlling the on / off state of other circuits.

[0035] Specifically, the alarm circuit includes a timer button SA1, a timer relay KT, and an alarm HZ. One end of the timer button is connected to the power module, and the other end is connected to the contacts and coil of the timer relay. The timer relay is connected to the alarm. The timer relay KT has multiple contacts. The KT1 contact is connected in series with the buzzer HZ and may be used to trigger the buzzer alarm at a specific time. The KT2 contact participates in the logic control of relays KA, KI2, KI3, etc.

[0036] The coil of time relay KT1 is connected in series with buzzer HZ, and then in parallel with the normally open auxiliary contact of contactor KM. When the coil of KM is energized, the coil of KT1 and HZ are energized simultaneously, the time relay KT1 starts timing, and the buzzer HZ sounds, indicating that the circuit is in a certain working state or has reached a certain time point, thus serving as an alarm or reminder.

[0037] Specifically, it also includes multiple indicator lights, which are connected to the autotransformer switch.

[0038] Indicator lights EL1, EL2, and EL3 are controlled by different switches or contacts. EL1 is the zero-position indicator, EL2 is the power indicator, and EL3 is the running indicator. By observing the on / off status of these indicator lights, operators can intuitively understand the circuit's operating status, facilitating timely problem detection and maintenance.

[0039] This utility model provides a power-side overcurrent relay with powerful protection functions, superior performance, strong adaptability, high reliability, and easy maintenance. It is used to detect the current in a circuit, and when the current exceeds a set value, it can promptly cut off the circuit, effectively preventing equipment damage and safety accidents caused by circuit overload and short circuit. It can protect against short circuits and current overloads in the circuit, ensuring the stable operation of the power system. It features high accuracy, low energy consumption, accurate delay, and a high return coefficient, ensuring that the relay can reliably return to its un-energized released state after operation. The load-side ammeter has advantages such as directly reflecting the load status, high-precision measurement, real-time monitoring, easy installation and maintenance, multiple selectable measurement ranges, remote monitoring and automated control, and high safety. This is of great significance for monitoring and adjusting the operating status of the load, timely detection and handling of abnormal situations in the circuit, and realizing overload and short-circuit protection, improving the stability and safety of the system and ensuring the safe and stable operation of the circuit. This combination allows the tested product to distinguish between AC and DC detection, and to accurately and quickly cut off the circuit when an alarm is triggered. These components are characterized by high accuracy, high automation, and safety and reliability. Their combined use can significantly improve the accuracy of the protection and monitoring process, making it more adaptable and reliable, and providing a more reliable safety guarantee for the entire circuit protection system.

[0040] The working principle of this utility model is as follows:

[0041] When the double-pole circuit breaker is closed, the circuit is ready for power. Pressing the start button SB2 energizes the control circuit, energizing the coil of the first contactor KM1. The main contacts of KM1 close, connecting the autotransformer BK to the circuit. The autotransformer adjusts the voltage according to actual needs to meet the load's operating requirements. Simultaneously, the normally open auxiliary contact of KM1 closes, achieving self-locking. This ensures that even after the start button SB2 is released, current continues to flow through the KM1 coil in the control circuit, guaranteeing continuous and stable circuit operation. KT2 closes after a delay, and the normally closed contacts KI2 and KI3 open.

[0042] As the circuit operates, when an overcurrent occurs, current relays KI1, KI2, and KI3 detect the current in each branch. If the overall circuit current reaches the set value, the corresponding contact KI1 closes. When measuring DC current, if the branch current reaches the rated value, the normally closed contact KI2 opens; when measuring AC current, KI3 opens, de-energizing the coil of the alarm self-locking relay KA, causing KA to open and KI1 to open. When current flows through the ammeter KI1, the KI1 contact closes, energizing KA, causing KA to close, and the normally closed contact of KA1 below SB1 to open, triggering the HZ alarm.

[0043] When it is necessary to stop the circuit, press the stop button SB1. The contactor KM coil will be de-energized, the main contacts will open, and the entire circuit will stop working.

[0044] Although embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for this utility model. Other modifications can be readily implemented by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and examples shown and described herein.

Claims

1. An ultra-high voltage power frequency withstand voltage detection device, characterized in that, include: The power module has one output end connected to the load circuit. A detection circuit is connected to the power module. The detection circuit includes a voltage regulation circuit and a control circuit, which are connected to the power module in parallel. A protection circuit, connected in series in the control circuit, activates to cut off the power supply when the current of the detection device is abnormal. The protection circuit includes two DC / AC selector switches, an overcurrent relay, a first alarm self-locking relay, a DC relay, an AC relay, and two second time-delay relays. One end of each of the DC and AC relays is connected to the two DC / AC selector switches, and the other end is connected to the two second time-delay relays. The coil of the first alarm self-locking relay is connected to its normally closed contact, the overcurrent relay, the DC relay, the AC relay, and the two second time-delay relays.

2. The ultra-high voltage power frequency withstand voltage detection device of claim 1, wherein, The voltage regulation circuit includes a first AC contactor and an autotransformer. One end of the first AC contactor is connected to the power module, and the other end is connected to one end of the autotransformer. The other end of the autotransformer is connected to the power module.

3. The ultra-high voltage power frequency withstand voltage detection device of claim 1, wherein, The control circuit includes a start-up circuit, a stop-up circuit, and an alarm circuit. The two ends of the start-up circuit, the stop-up circuit, and the alarm circuit are respectively connected to the power supply module. The coil of the first alarm self-locking relay is connected to the alarm circuit, and the DC / AC selector switch is connected to the start-up circuit.

4. The ultra-high voltage power frequency withstand voltage detection device of claim 3, wherein, The start / stop circuit includes a start button, an autotransformer switch, a second time-delay relay, a second AC contactor, a second alarm self-locking relay, and a stop button. One end of the autotransformer switch is connected to the power module, and the other end is connected to one end of the start button. The other end of the start button is connected to the second time-delay relay and the second AC contactor. One end of the second AC contactor is connected to one end of the stop button, and the other end of the stop button is connected to the power module.

5. The ultra-high voltage power frequency withstand voltage testing device as described in claim 3, characterized in that, The alarm circuit includes a timer button, a timer relay, and an alarm. One end of the timer button is connected to the power module, and the other end is connected to the contacts and coil of the timer relay. The timer relay is connected to the alarm.

6. The ultra-high voltage power frequency withstand voltage testing device as described in claim 4, characterized in that, It also includes multiple indicator lights, which are connected to the autotransformer switch.

7. The ultra-high voltage power frequency withstand voltage testing device as described in claim 1, characterized in that, The power module is connected to the circuit via a bipolar circuit breaker, and after the circuit breaker, a power supply side ammeter is connected to the load circuit.

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