CN107271831A - A kind of novel transformer substation secondary cable alignment device and method - Google Patents

Abstract

The invention discloses a new type of substation secondary cable alignment device, which includes a side end and a measuring end respectively arranged at both ends of the secondary cable to be tested and a voltage measuring device for measuring the voltage at both ends of the secondary cable. The said side end is provided with a power supply, a switch K1, N terminals and N+1 connection resistors connected in series on both sides of the power supply and the switch, and the N terminals are respectively connected to any two adjacent connection resistors. Nodes are connected. In the present invention, by setting the wiring terminals and setting the wiring resistance between the wiring terminals, and then connecting all the wiring resistances in series at a certain voltage, the voltage value between any two points of each wiring terminal can be determined. Therefore, it is possible to formulate a voltage difference table, and then measure the voltage at the other end of the secondary cable to be tested, and determine the corresponding label through the table look-up method, so that the alignment of the cable can be completed. The two are convenient and fast as a whole, and the cost is low ,High precision.

Description

A new substation secondary cable alignment device and method

technical field

The invention relates to the technical field of electric power system maintenance equipment, in particular to a novel substation secondary cable alignment device and method.

Background technique

At present, in the construction and renovation of substations, a large number of secondary cables are used to connect different power equipment. For the sake of beauty, the cables are usually laid in cable trenches. Therefore, when laying secondary cables, marks will be made on both sides of the same cable to facilitate identification of the cable direction. After the cable is laid, in order to connect accurately, the staff will carry out alignment work at the working positions on both sides of the same cable, that is, to confirm the one-to-one correspondence of each core wire one by one, and make identification marks. The common practice is that one person short-circuits two core wires on one side of the cable, and the other person uses a multimeter on the opposite side to measure the two short-circuited core wires, and uses a walkie-talkie to communicate. In order to save manpower, the wiring device is also used in actual work, but the wireless transmission technology is generally used, and the use of wireless communication equipment is prohibited in the relay protection room of the substation. However, some substation relay protection rooms use more electromagnetic relays, and wireless communication equipment may affect the stable operation of substations. Therefore, the State Grid Corporation of China prohibits the use of wireless communication equipment in substation relay protection rooms.

Contents of the invention

The purpose of the present invention is to provide a new type of substation secondary cable alignment device and method, which can mark each core wire on the side of the secondary cable at the same time without using wireless transmission technology, so that each core wire can be connected to a different potential , through the secondary cable itself to form a path, measure the voltage of any two core wires on the other side of the secondary cable, and determine the mark of the selected core wire through the look-up table method. This method can well meet the working environment of the substation relay protection room, and can quickly and accurately complete the secondary cable alignment work, saving manpower.

The technical scheme adopted in the present invention is:

A new type of substation secondary cable alignment device, including a side end and a measurement end respectively arranged at both ends of the secondary cable to be tested and a voltage measuring device for measuring the voltage at both ends of the secondary cable. The end is provided with a power supply, a switch K1, N terminals and N+1 wiring resistors connected in series on both sides of the power supply and the switch, and the N terminals are respectively connected to the wiring nodes of any two adjacent wiring resistors, And the N terminals are correspondingly provided with labels; the measuring terminal is a measuring line plug-in strip with a label, and the number of plug-in jacks is not less than N; the voltage value between any two terminals not equal.

The voltage value of the power supply is equal to the sum of the resistance values of the N+1 wiring resistors.

The voltage measuring device is a multimeter.

It also includes an LED indicator light, and the LED indicator light L1 is connected in parallel with a series circuit composed of N+1 wiring resistors.

A novel substation secondary cable alignment method includes the following steps:

A: First, determine the number N of core wires of the secondary cable to be tested, select N+1 wiring resistors, calculate the resistance and M of the N+1 wiring resistors, select a power supply with a power supply value of M, and pass the series circuit The principle of voltage division can calculate the voltage value between both ends of any wiring resistance and between any end of any wiring resistance and any section of other wiring resistances, distinguish the two contacts of voltage measurement, and formulate a voltage difference table;

B: Then connect N+1 wiring resistors in series between the power supplies through the switch, and at the same time connect one end of the core wire of the N secondary cables to the wiring node between any two wiring resistors, and connect the wiring nodes in turn serial number;

C. Use a voltage measuring device to measure the voltage at the other end of the core wires of any two secondary cables to be tested, and compare the measurement results with the voltage difference table to obtain the corresponding numbers of the two core wires currently being tested. Then measure and look up the table (N-2)/2 or (N-1)/2 times in sequence to realize the alignment of the core wires.

The voltage measuring device is a multimeter.

It also includes an LED indicator light, which is connected in parallel with a series circuit composed of N+1 wiring resistors.

In the present invention, by setting the wiring terminals and setting the wiring resistance between the wiring terminals, and then connecting all the wiring resistances in series at a certain voltage, the voltage value between any two points of each wiring terminal can be determined. Therefore, it is possible to formulate a voltage difference table, and then measure the voltage at the other end of the secondary cable to be tested, and determine the corresponding label through the table look-up method, so that the alignment of the cable can be completed. The two are overall convenient and fast, and the cost is low ,High precision.

Description of drawings

Fig. 1 is a schematic block diagram of the circuit structure of the present invention;

Fig. 2 is a flowchart of the present invention.

detailed description

As shown in Figure 1, the present invention includes the side end and the measuring end respectively arranged at the two ends of the secondary cable to be tested and a voltage measuring device for measuring the voltage at both ends of the secondary cable, and the said side end is provided with power supply, switch K1, N terminals, and N+1 wiring resistors connected in series on both sides of the power supply and the switch, the N terminals are respectively connected to the wiring nodes of any two adjacent wiring resistors, and N Labels are correspondingly provided on the terminals; the measuring terminal is a measuring line plug-in strip with a label, and the number of plug-in jacks is not less than N. The voltage value of the power supply is equal to the sum of the resistance values of the N+1 wiring resistors. If they are set to be equal, the measured voltage values can be integers, which is convenient for checking. However, the voltage values between any two terminals are not equal, by considering the unequal voltage values between any two terminals when setting the resistance, the unique correspondence of the voltage values can be determined, and it can also be used for checking table method lays the foundation.

The voltage measuring device is a multimeter, and since the multimeter itself has two measuring terminals, red and black, it is convenient for measurement and comparison.

It also includes an LED indicator light, which is connected in parallel with a series circuit composed of N+1 wiring resistors.

The tested terminal of the present invention is composed of a DC voltage source Vdc, a power control switch K1, a power indicator light L1 and resistors R1-R11. A terminal block with 10 holes is reserved. The test terminal is a terminal block with 10 holes.

The terminal under test divides the DC voltage source through 11 resistors to obtain 10 potential values, which are respectively connected to the 1~10 holes of the terminal block of the terminal under test. Peel off the cable sheath at both ends of the secondary cable respectively, so that the core wire exposes a section of bare copper wire and connect it to the terminal under test and the test end.

Before starting work, mark each secondary cable core wire at the tested end, and determine the tested end mark of the tested core wire by measuring the potential difference between the two core wires at the measuring end.

A novel substation secondary cable alignment method includes the following steps:

A: First, determine the number N of core wires of the secondary cable to be tested, select N+1 wiring resistors, calculate the resistance and M of the N+1 wiring resistors, select a power supply with a power supply value of M, and pass the series circuit The principle of voltage division can calculate the voltage value between the two ends of any wiring resistance and any end of any wiring resistance and any section of other wiring resistance, and formulate the voltage difference table; since the number of secondary cable cores N to be tested is determined, it is expected to pass Different potentials are applied to each core wire of the secondary cable, so that the potential difference (voltage) between any two core wires is unique. Considering the measurement error, the accuracy of each potential value should not be less than 1V. In this way, the voltage value obtained by using the multimeter to measure any two core wires is in one-to-one correspondence with the number of the corresponding core wires of the red and black test pens, and there will be N×(N−1) corresponding relationships, which can be drawn into a table. These potential values can be obtained by using one or more DC voltage sources through multiple resistors in series to divide the voltage. The number of resistors should not be less than (N-1), and common k-ohm resistors can be used.

B: Then connect N+1 wiring resistors in series between the power supplies through the switch, and at the same time connect one end of the core wire of the N secondary cables to the wiring node between any two wiring resistors, and connect the wiring nodes in turn serial number;

C. Use a voltage measuring device to measure the voltage at the other end of the core wires of any two secondary cables to be tested, and compare the measurement results with the voltage difference table to obtain the corresponding numbers of the two core wires currently being tested. Then measure in sequence to realize the alignment of the core wires.

The voltage measuring device is a multimeter. The multimeter can detect voltage, and the stylus comes with classification marks (red pen, black pen) which are more convenient to use.

It also includes an LED indicator light, which is connected in parallel with a series circuit composed of N+1 wiring resistors.

Take a 10-core secondary cable as an example for specific wiring, let Vdc=100V, R1=1kΩ, R2=1kΩ, R3=2kΩ, R4=4kΩ, R5=5kΩ, R6=8kΩ, R7=10kΩ, R8= 14kΩ, R9=21kΩ, R10=26kΩ, R11=8kΩ. After the secondary cable is connected to the wire alignment device, the core wires corresponding to holes 1 to 9 of the terminal row under test are marked as 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 respectively. After measuring that Vdc is 100V, close K1. After finding that L1 is lit, the staff goes to the measurement end of the secondary cable, uses a multimeter to measure any two core wires, and obtains a voltage value. Take 17V as an example, through the look-up table method Determine the marks of the two core wires to be tested. The black test pen of the multimeter measures the core wire as 6, and the red test pen of the multimeter measures the core wire as 3. The marks of all the core wires can be determined by measuring a total of 5 times. If the measured voltage is negative, just reverse the red and black test leads. Take -17V as an example. At this time, the red test lead of the multimeter measures 6, and the black test lead of the multimeter measures 3. By analogy, by specific data measurement, the table used by the table look-up method is shown in the following table 1 in this embodiment:

The terminal under test is composed of DC voltage source Vdc, power control switch K1, power indicator light L1 and resistors R1~R11. A terminal block with 10 holes is reserved. The test terminal is a terminal block with 10 holes.

The terminal under test divides the DC voltage source through 11 resistors to obtain 10 potential values, which are respectively connected to the 1~10 holes of the terminal block of the terminal under test. Peel off the cable sheath at both ends of the secondary cable respectively, so that the core wire exposes a section of bare copper wire and connect it to the terminal under test and the test end.

Before starting work, mark each secondary cable core wire at the tested end, and determine the tested end mark of the tested core wire by measuring the potential difference between the two core wires at the measuring end.

Claims (7)

1. a kind of novel transformer substation secondary cable alignment device, it is characterised in that：Including being separately positioned on secondary cable two to be measured The voltage measuring apparatus measured by side and measurement end and to secondary cable both end voltage at end, it is described to be set by side It is equipped with power supply, switch K1, N number of terminals and is connected on power supply and switchs N+1 connection resistance of both sides, described N number of wiring Hold the wiring node of connection resistance adjacent with any two to be respectively connected, and label is correspondingly arranged on N number of terminals；Described Measurement end is that with labelled survey line insert row, and the number of insert row jack is not less than N；Electricity between any two terminals Pressure value is unequal.

2. novel transformer substation secondary cable alignment device according to claim 1, it is characterised in that：The electricity of described power supply Pressure value size is equal with the resistance value sum of N+1 connection resistance.

3. novel transformer substation secondary cable alignment device according to claim 2, it is characterised in that：Described voltage measurement Device is universal meter.

4. novel transformer substation secondary cable alignment device according to claim 3, it is characterised in that：Also include LED to refer to Show lamp, the series circuit that the LED light L1 is constituted with N+1 connection resistance is in parallel.

5. a kind of novel transformer substation secondary cable is to line method, it is characterised in that：Comprise the following steps：

A：First, the cored wire quantity N of secondary cable to be measured is determined, N+1 connection resistance is chosen, N+1 connection resistance of calculating Resistance and M, choose the power supply that power values are M, any one connection resistance two can be calculated to obtain by the voltage divider principle of series circuit Magnitude of voltage between end and the either end and other connection resistance either segments of any connection resistance, distinguish voltage measurement two Contact, and formulate voltage difference table；

B：Then N+1 connection resistance is connected between the power supplies, while one end of the cored wire N number of secondary cable by switch Wiring node is connected between any two connection resistances respectively, and butted line node number consecutively respectively；

C, carries out voltage measurement, according to survey using voltage measuring apparatus to the other end of the cored wire of any two secondary cable to be measured Amount result by with voltage difference table compare so as to obtain currently be tested two cored wires reference numeral, then again successively measurement and Table look-up（N-2）/ 2 or (N-1)/2 time be can be achieved cored wire to line.

6. novel transformer substation secondary cable according to claim 5 is to line method, it is characterised in that：Described voltage measurement Device is universal meter.

7. novel transformer substation secondary cable according to claim 6 is to line method, it is characterised in that：Also include LED to refer to Show lamp, the series circuit that the LED light is constituted with N+1 connection resistance is in parallel.