SU661414A1 - Arrangement for measuring electric network insulation resistance - Google Patents

Description

The first additional block is comparable to the Sh y gvorgvogbumnnzhzhytel whose output is connected to the second input of the comparison unit associated with its output with the first input of the second divider, the output of the latter is connected to the recording device and the first inputs of the third divider, the second multiplier and adder, and the outputs of the second multiplier and the adder is connected to the first and second inputs of the third divider respectively, the output of the latter is connected with the first additional recording device, the input of the second additional register The device is connected to the second inputs of the second multiplier and madator, as well as to the output of the third divider, the second input of which is connected to the output of the second storage unit and the first input of the first additional comparison unit, the output of the latter connected to: the first input of the third multiplier, connected the output with the second input of the second divider, the second input of the third multiplier is connected to the output of the fourth multiplier, both inputs of the last are connected to the first input of the comparator unit and to the second input of the first multiplier, while The output of the inverter is connected to the input of the fourth key, the first output of which is connected via the first constant resistor to the case, the second output of the fourth key is connected to the second input of the third key, the first output of the first key and to the input of the clock distributor, the output of the last connected NC to the second input of the second key connected to the output of the second storage unit, and the second output of the first key through the second constant resistor is connected to the housing.

The drawing shows a functional diagram of the device.

A device for measuring the insulation resistance of electrical networks consists of a source of adjustable voltage 1, a recording device 2 and a unit of comparable. neither, 3. In order to increase speed, while improving accuracy and expanding the field of application, four keys 4–7, two permanent resistors 8, 9, two additional recording devices 10, II, a clock distributor 12, four dividers 13–16, four multipliers 17 are entered into the device. -20, comparison unit 21, two storage units 22, 23, adder 24, inverter 25. Moreover, input terminal 26 through inverter 25 is connected to the first input of divider 13 and via switch 4 to resistor 8, and input terminal 27 is connected to second input divider 13 and through key 5 with re stories 9, resistors 8 and 9 are connected with a common schinoy device-, yield divider 13 through the key 6 is connected to the input of the memory unit 22 and simultaneously through the switch 7 - to the input of the storage unit 23, the output of which

connected to the first input of block 3, the output of which is connected to the first input of multiplier 17, the output of storage unit 22 is connected to the second input of block 3 and simultaneously with the first input of multiplier 18. The output of adjustable source. constant voltage 1 is connected to two inputs of multiplier 19 and simultaneously with the second input of the multiplier 18 and with the first input of the block 21, and the total source of this source 1 is connected to the earth terminal of the device. The output of the multiplier 18 is connected to the second input of the block 21. The output of the multiplier 19 is connected to the second input of the multiplier 17, the output of which is connected to the first input of the divider 14.

5 The output of block 21 is connected to the second.

the input of the divider 14, the output of which is connected to the registering device 2 and simultaneously with the first inputs of the multiplier 20, the adder 24 and the divider 15. The output of the divider 15 is connected to the device 10 and

. at the same time with the second inputs of the adder .24 and multiplier 20, the output of which is connected by the first input of the divider 16. The output of the adder 24 is connected to the second input of the divider 16, the output of which is connected

5 with the device 11. The control inputs of the keys 4, 5, 6 are connected by the inverter output of the clock distributor 12, the direct output of which is connected to the control input of the key 7. - When measuring the insulation resistance

0 AC power input terminal 26 is connected to the inverter 25 through the filter 28, and the input terminal 27 is connected to the key 6 and the second input of the dividing device 17 through Phil, Tr. 29.

 The device works as follows. The input terminals 26 and 27 are connected to both poles of the measured connection, and the earth on the device terminal is connected to the earth bar of the network. At time tn,

where n 1, 3, 5, 7 ... the voltage drop гг of the insulation resistance of the first pole (Ui) is inverted by inverter 25 and fed to the first input of the divider 13, and the voltage applied to the insulation resistance of the second pole (Uj) enters the second entrance

5 divider 13, which produces a signal A equal to the voltage ratio () .- And through the key 7 goes to the analog storage unit 23, which stores this signal before the next one arrives. At the next time point Tn + i, the insulation resistance of the first pole is shunted through the key 4 with the known resistance of the resistor 8, and the insulation resistance of the second pole through the key. 5 with the known resistance of the resistor 9. The voltage drop across the insulation resistance of the first pole, shunted by the resistance of resistor 8 (Uii), is fed to the first input of the divider 13, and the voltage drop across the insulation resistance of the second pole, shunted by the resistance of resistor 9 (Uai arrives at the second input of the divider 13, which produces a signal (Ao) equal to the ratio () and through the key 6 enters the analog storage unit 22, which stores this signal before the next one arrives.

The signal (A |) from the storage unit 23 is fed to the first input of block 3, and the signal (To) from block 22 to the second input of block 3, which generates a signal equal to the difference (Ai-AO).

From the output of an adjustable DC source 1, a signal equivalent to the known resistance is fed to both inputs of multiplier 19, which generates a signal (R), the output of which is fed to the input of multiplier 17, to the other input which receives a signal (A | -AO) from block 3. The multiplier .17 forms the signal R (Ai-AO). From the output of block 22, the signal (Ao) is fed to one input of the multiplier. 18, the second input of which receives the signal (R) of the adjustable source 1.

The multiplier 18 generates a signal (AgR).

From the adjustable source 1, the signal (R) is fed to the first input of block 21, to the second input of which a signal (AoR) is received from the multiplier 18. Block 21 generates a signal (R-AoR).

The signal R (A | - AO) from the output of the multiplier 17 is fed to the first input of the divider 14, the second input of which receives the signal (R - AoR) from block 21. The divider 14 generates a signal (Rxi), which goes to the device 2, showing the value insulation resistance of the first pole.

The signal (Rxt) from divider 14 goes to the first input of divider 15, the second input of which receives a signal (Ai) from the output of block 23. Divider 15 generates a signal (RXS) to the device 10, showing the value of the insulation resistance of the second pole.

The signal (Rxi) from the output of the divider 14 is fed to the first inputs of the multiplier 20 and the adder 24, the second inputs of which receive a signal (RHD) from the output of the divider 15.

The multiplier generates a signal (RxjRxi.) Arriving at the first input of the divider 16.

The adder 24 generates a signal (Rxj supplied to the second input of the divider 16, which generates a signal (RitaxS) fed to the device 11, indicating the value of the equivalent insulation resistance.

When measuring insulation resistance in AC networks, the device is connected through filters 28 and 29.

A device for measuring the insulation resistance of electrical networks allows an individual continuous measurement of the insulation resistance of the two poles of the electric network, providing complete automation and high speed, which is of great importance on ships. At the same time, the obtained information on the magnitude of the insulation resistance of each of the poles makes it possible to carry out repair work in a shorter time, as indicated by the isolation of which of the network poles is to be restored.

This factor contributes to a significant economic effect, not to mention the effect created by the increase in speed, which allows the use of one device to monitor the state of isolation of a large number of networks.

Claims (2)

1. Tsapenko, EF. Insulation resistance control in networks up to 100 V M, Energie, 1972, p. 126. 2. Device for automatically measuring the resistance of the insulation of DC networks. USSR Author's Certificate No. 460514, MKI G 01 R 27/18, 05/29/73.