CN104360134A - A live voltage measurement device capable of preventing transient overvoltage - Google Patents

Abstract

A voltage live measuring device capable of preventing transient overvoltage, comprising a closed insulating casing, a voltage measuring device arranged in the casing, first and second shielding sleeves set on the casing, the voltage measuring The device is provided with first and second test lines extending to the outside of the casing, and the outer peripheral surface of the second test line, the voltage measuring device and the first test line in the casing is wrapped with a third shielding sleeve, and the first and second test lines The two shielding sleeves are correspondingly electrically connected to the first test line and the third shielding sleeve, the first and second shielding sleeves are spaced apart to form a barrier gap, and the opposite annular edges of the first and second shielding sleeves are respectively formed with at least A discharge lobes, the discharge lobes of the first and second shielding sleeves are arranged opposite to each other to form a discharge gap, the discharge gap can discharge when a transient overvoltage occurs, lead the fault arc to the outside of the shell, and prevent the arc from damaging the shell A voltage measuring device in the body.

Description

A live voltage measurement device capable of preventing transient overvoltage

technical field

The invention relates to a voltage live measuring device capable of preventing transient overvoltage, in particular to a device for measuring the terminal voltage of a contact resistance to calculate the resistance value of the contact resistance.

Background technique

People usually hope that the resistance of electrical contacts to the circuit at the contact point is zero, that is, the contact resistance is zero. However, a large number of experiments have shown that the resistance of electrical contact parts exists more or less, and the influence on the circuit cannot be ignored. Therefore, it is very important to study the contact resistance of electrical appliances to reduce the influence on the circuit.

Contact resistance is the resistance generated by two contact elements at the contact position. Whether the contact element is reliable or not, the normal diversion circuit is generally several to tens of micro-ohms, and hundreds or even thousands of micro-ohms appear, which essentially lies in Whether the resistivity, pressure, and effective cross-section of the contact part are stable or not, the contact resistance is the ratio of the potential difference on both sides of the contact surface to the current passing through the contact surface, which conforms to Ohm's law, that is, R _X = U/I, the current measurement of contact resistance The methods are all carried out offline (offline). The measuring device provides a DC power supply to both ends of the contact resistance, and U and I are measured by the ammeter and voltmeter, and then the contact resistance R _X is calculated. Due to the potential difference of the contact resistance measurement under the strong current in the power system, it is necessary to consider the interference under the strong electric field and the strong magnetic field and the safety of the measuring device to the system and the measuring device itself, so the prior art is not charged. Method and device for measuring contact resistance potential difference.

Contents of the invention

The purpose of the present invention is to provide a measuring device capable of measuring the contact resistance potential difference with electricity, aiming at the deficiencies of the prior art.

The purpose of the present invention is achieved through the following technical solutions:

A voltage live measurement device capable of preventing transient overvoltage, used to measure the voltage of the contact resistance of a high-voltage circuit to calculate the resistance value, is characterized in that it includes a closed insulating casing, a voltage measuring device arranged in the casing, The first and second shielding sleeves are sleeved on the housing, the voltage measuring device is provided with first and second test lines extending to the outside of the housing, the second test line, the voltage measuring device and the The outer peripheral surface of the first test line is wrapped with a third shielding sleeve, the first and second shielding sleeves are correspondingly electrically connected to the first test line and the third shielding sleeve, and the first and second shielding sleeves are arranged at intervals to form a barrier In the gap, at least one discharge lobes are respectively formed on the opposite annular edges of the first and second shielding sleeves, and the discharge lobes of the first and second shielding sleeves are oppositely arranged to form a discharge gap.

Further, the present invention also includes a first wireless communication module disposed in the housing and connected to the voltage measurement device, and a terminal device provided with a second wireless communication module, and the voltage measurement device communicates with the voltage measurement device through the first and second wireless communication modules. Terminal equipment realizes data transmission.

Further, the housing is provided with an insulating operating rod, and the second shielding sleeve is provided with an escape hole for the insulating operating rod to pass through, and the first wireless communication module transmits data through the escape hole.

Further, the discharge gap is equal to 1/5-3/5 of the barrier gap.

Further, the discharge lobes are arc-shaped.

Further, the opposite annular edges of the first and second shielding sleeves are respectively formed with three discharge lobes distributed at equal intervals.

Further, the first and second wireless communication modules are Bluetooth communication modules or WiFi communication modules.

Further, at least one of the first and second shielding sleeves is movably sleeved on the casing to adjust the size of the discharge gap.

Further, the first and second shielding sleeves are both composed of a collar surrounding the outer peripheral surface of the shell and a sealing plate closing the end surface of the collar.

Further, the barrier gaps between the opposite annular edges of the first and second shielding sleeves are equal everywhere.

The present invention has following beneficial effect:

Set the voltage measuring device in the casing, and set the first and second shielding sleeves outside the casing, the first and second test lines and the outer peripheral surface of the voltage measuring device are wrapped with a third shielding sleeve, which can shield the electric field and magnetic field to prevent the voltage measuring device from being disturbed by the electric field and magnetic field, and ensure the measurement accuracy of the voltage measuring device; several groups of relative discharge lobes are set between the first and second shielding sleeves, and a discharge gap is formed between the relative discharge lobes , the discharge gap can be discharged when a transient overvoltage occurs, leading the fault arc to the outside of the shell, preventing the arc from damaging the voltage measuring device inside the shell, and the arc-shaped design of the discharge lobes can make the electric field of the discharge gap uniform, ensuring discharge The gap has good discharge repeatability; the discharge gap can also be adjusted to adapt to different working conditions; an insulating operating rod is set on the shell, which is convenient for the operator to carry out high-level live measurement and ensures operational safety; the voltage measurement device passes The wireless communication module realizes wireless communication with the terminal equipment, and can transmit the measurement data to the terminal equipment, so as to observe and record the measurement results conveniently.

Description of drawings

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Fig. 1 is a structural schematic diagram of the present invention.

Fig. 2 is a functional block diagram of the present invention.

Fig. 3 is a cross-sectional view of the present invention.

Detailed ways

Referring to Fig. 1, Fig. 2 and Fig. 3, a voltage live measuring device capable of preventing transient overvoltage includes an insulating housing 1, a voltage measuring device 3, a first shielding sleeve 21, a second shielding sleeve 22, a first Three shielding sleeves 52, insulators 53, the first bluetooth communication module 4 and the mobile phone 6, wherein the first shielding sleeve 21, the second shielding sleeve 22, and the third shielding sleeve 52 are metal materials such as copper and aluminum.

The casing 1 is cylindrical, and an insulating operating rod 11 is arranged below it. The insulating operating rod 11 can be a telescopically adjustable rod-shaped body. The casing 1 can be lifted to a high position through the insulating operating rod 11 to measure the The potential difference of the contact resistance R, the first and second shielding sleeves 21, 22 are set outside the housing 1, and the first shielding sleeve 21 is formed by the ring 211 surrounding the outer peripheral surface of the housing 1 and the sealing ring 211 end surface. plate 212, the second shielding sleeve 22 is composed of a collar 222 surrounding the outer peripheral surface of the housing 1 and a sealing plate 223 closing the end face of the collar 222, and the second shielding sleeve 22 is provided with a space for the insulating operating rod 11 to pass through. The hole 221, the voltage measuring device 3 is arranged inside the housing 1, and the first and second test lines 31 and 32 extending to the outside of the housing 1 are provided for measuring the potential difference between the two ends of the contact resistance R. The housing 1 and the sealing Plates 212, 223 are formed with relief holes for the first and second test lines 31, 32 to pass through, the third shielding sleeve 52 wraps the second test line 32, the voltage measuring device 3 and part of the first test line 31, and the insulator 53 A central hole for the first test line 31 to pass through is formed on the housing 1, wherein the first and second shielding sleeves 21, 22 correspond to the first test line 31 and the third shielding sleeve 52 through wires 331, 332 Conductive connection, the first and second shielding sleeves 21, 22 are arranged at intervals to form a barrier gap D, the barrier gap D between the opposite annular edges of the first and second shielding sleeves 21, 22 is equal everywhere, the first and second shielding Three discharge lobes 211 , 221 at equal intervals are respectively formed on opposite ring edges of the sleeves 21 , 22 .

The first bluetooth communication module 4 is arranged in the casing 1 and is connected with the voltage measuring device 3, and the transmitting antenna 41 of the first bluetooth communication module 4 is arranged near the hole 221, and the measurement data is sent to the outside through the hole 221, and the mobile phone 6 has a built-in second Bluetooth communication module 61, and the voltage measurement device 3 realizes data transmission with the mobile phone 6 through the first and second Bluetooth communication modules 4, 61, and the mobile phone 6 receives the data and displays the measurement results.

The specific measurement method is: the housing 1 is lifted to a high position through the insulating operating rod 11, and the two test lines 31, 32 of the voltage measuring device 3 are conductively connected with the two ends of the contact resistance R, and the voltage measuring device 3 passes the measurement result through the first 1. The second bluetooth communication module 4, 61 sends it to the mobile phone 6, and the mobile phone 6 receives and displays the measurement result. When a lightning strike causes a transient overvoltage, the discharge gap L is discharged to lead the fault arc to the outside of the housing 1. The arc is prevented from damaging the voltage measuring device 3 inside the housing 1 .

The above is only a preferred embodiment of the present invention, so it cannot limit the scope of the present invention, that is, equivalent changes and modifications made according to the patent scope of the present invention and the content of the specification should still belong to the present invention covered by the patent.

Claims (10)

1. A voltage live measuring device capable of preventing transient overvoltage, used to measure the voltage of the contact resistance of the high-voltage circuit to calculate the resistance value, is characterized in that: it includes a closed insulating casing, a voltage measuring device arranged in the casing device, the first and second shielding sleeves set on the casing, the voltage measurement device is provided with first and second test lines extending to the outside of the casing, the second test line, the voltage measurement device and the casing The outer peripheral surface of the first test line is wrapped with a third shielding sleeve, and the first and second shielding sleeves are correspondingly electrically connected to the first test line and the third shielding sleeve, and the first and second shielding sleeves are arranged at intervals of A barrier gap is formed, and at least one discharge lobes are respectively formed on opposite annular edges of the first and second shielding sleeves, and the discharge lobes of the first and second shielding sleeves are oppositely arranged to form a discharge gap. 2. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, characterized in that: it also includes a first wireless communication module arranged in the casing and connected to the voltage measurement device, and a second The terminal equipment of the wireless communication module, the voltage measurement device realizes data transmission with the terminal equipment through the first and second wireless communication modules. 3. A voltage live measurement device capable of preventing transient overvoltage according to claim 2, characterized in that: the housing is provided with an insulating operating rod, and the second shielding sleeve is provided with an insulating operation lever. A relief hole through which the rod passes, and the first wireless communication module transmits data through the relief hole. 4. A voltage charging measuring device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that: the discharge gap is equal to 1/5-3/5 of the barrier gap. 5. A voltage electrification measuring device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that: the discharge lobes are arc-shaped. 6. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that: the opposite annular edges of the first and second shielding sleeves are respectively formed with equidistant distribution The three discharge lobes. 7. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, 2 or 3, wherein the first and second wireless communication modules are Bluetooth communication modules or WiFi communication modules. 8. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that at least one of the first and second shielding sleeves is movably sleeved on the casing to adjust the size of the discharge gap. 9. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that: the first and second shielding sleeves are both made of a collar surrounding the outer peripheral surface of the housing It is composed of a sealing plate that closes the end face of the collar. 10. A voltage live measurement device capable of preventing transient overvoltage according to claim 1, 2 or 3, characterized in that: the barrier gap between the opposite annular edges of the first and second shielding sleeves is everywhere equal.