JPS6258209B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a protective relay device that allows inspection to be performed with high accuracy and improves reliability.

In recent years, many protective relay devices for protecting power systems are equipped with so-called monitoring functions such as constant monitoring and automatic inspection in order to improve their reliability. Under normal conditions, when the device input is not at its operating level, constant monitoring will detect malfunctions of the device, and automatic inspection will check whether the device is operating correctly when the device input is at its operating level. Detection of malfunction or malfunction is performed by applying a check input.

FIG. 1 shows the configuration of such a conventional protective relay device. In the figure, 1 is a switching circuit equipped with a changeover switch SW. In a normal state, the changeover switch SW is on the C1 side, and the amount of electricity (voltage in the figure) S ₀ of the power system (not shown) is transferred to the input transformer 2. Added. And this input transformer 2
The determination unit 3 converts it into a predetermined amount of electricity by
will be introduced in Next, in the determination section 3, the output electricity quantity of the input transformer 2 and the output electricity quantity S1 of the reference quantity output circuit 4, in which the reference quantity S1 of the magnitude corresponding to the relay operation setting value is set, are determined. By comparing the sizes, the operation of the relay is determined. On the other hand, when the inspection command signal S2 is applied to the switching circuit 1, the changeover switch SW is switched to the C2 side. As a result, from the inspection circuit 5, a voltage signal obtained by dividing the voltage of the power supply E by the first resistor R1 and the second resistor 2 is transmitted to the input transformer 2 as the inspection input S3 via the changeover switch SW. added to. In this case, since the inspection input S3 is set to a value at which the relay should operate (for example, a value greater than S1 above), the inspection input at the operating level is sent from the input transformer 2 to the determination unit 3. The system can be inspected by checking whether the determining section 3 operates correctly.

By the way, in such a protective relay device, as mentioned above, the magnitude of the inspection input S3 is determined by the voltage division ratio of each resistor R1 and R2 in the inspection circuit 5, and therefore, inspection at a certain level is not possible. Since only the input S3 can be inspected, it is impossible to strictly inspect the relay operation with respect to the level of the reference electric quantity S1 of the reference quantity output circuit 4 whose setting is changed in response to changes in the operating setting value. be.
Therefore, as a countermeasure to this problem, the first or second resistor R1 or R2 of the inspection circuit 5 should be made variable, and when the setting of the reference electricity quantity S1 is changed, the magnitude thereof should be changed to match it. Bye. According to such a means, it is possible to apply the inspection input S3 of a magnitude that matches the level of the reference electricity quantity S1, that is, the operation setting value of the relay, and it becomes possible to perform accurate inspection.

However, in such means, when changing the setting of the reference electrical quantity S1 of the reference quantity output circuit 4, the first or second resistor R1,
The setting of R2 must also be changed, which is very troublesome. Further, if a circuit is constructed so as to be able to vary the resistors R1 and R2, there is a drawback that the construction of the inspection circuit 5 becomes complicated and large.

The present invention has been made in view of the above circumstances, and provides a protective relay device for protecting an electric power system, in which the magnitude of the inspection input can be changed in accordance with changes in the operating setting value of the device. The purpose of the present invention is to provide a protective relay device which eliminates the need to change the setting of the inspection input even when changing the setting of the operation setting value and allows accurate inspection with a simple circuit configuration. do.

In order to achieve the above object, the protective relay device of the present invention includes a reference quantity output circuit that outputs a reference quantity of electricity of a magnitude corresponding to a relay operation setting value whose setting can be changed; An inspection input/output means that receives a reference quantity of electricity as an input and outputs an inspection input that changes in accordance with the magnitude of the reference quantity of electricity, the inspection input from this inspection input/output means, and the electricity of the power system to be protected. The input is a switching circuit that switches and outputs the electrical quantity of the power system at all times and the inspection input when an inspection command is applied, the output from this switching circuit, and the reference electrical quantity from the reference quantity output circuit. , and determining means for comparing the magnitude relationship between the two to make a relay determination.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows the configuration of the protective relay device, and the figure shows the case of an overvoltage detection relay. In the figure, 6 is a switching circuit whose inputs are a voltage S ₀ ' of a power system (not shown) applied via an input transformer 7 and an inspection input (voltage) S4, which will be described _later. Also, during inspection, the inspection input S4 is switched and sent as the husband output S6 in accordance with the inspection command S5. Further, 8 is a reference quantity output circuit that outputs a reference quantity of electricity S7 of a magnitude corresponding to the relay operation setting value, and inputs this reference quantity of electricity S7 to the determination section 9, and an amplifier circuit 10 which is an inspection input/output means. is input to obtain the inspection input S4. The determination section 9 receives the output S6 of the switching circuit 6 and the output S7 of the reference amount output circuit 8 as inputs, and determines whether or not to operate based on these inputs. In the above, the amplification degree of the amplifier circuit 10 is set so that the inspection input S4 causes the reference electrical quantity S7 to be a value slightly larger than the relay operation setting value. Further, as the reference amount output circuit 8, a well-known reference amount setting circuit that is set by changing the resistance value that divides the power supply voltage is used.

Next, the operation of this configuration will be described. First, the system input S ₀ ' converted into a predetermined electrical quantity from the switching circuit 6 through the input transformer 7 is normally applied to the determination section 9 as S6. Further, a reference quantity of electricity S7 is also applied from the reference quantity output circuit 8 to the determination section 9. Then, the determination unit 9 compares the magnitude of the output S6 of the switching circuit 6 and the reference electricity amount S7 to perform a relay determination.

Next, at the time of inspection, input switching is performed by giving an inspection command S5 to the switching circuit 6, and the inspection input S4 obtained by multiplying the output S7 of the reference amount output circuit 8 by a certain value through the amplifier circuit 10 is determined as the output S6. Added to section 9. Then, in the determination section 9, a relay determination is performed in the same manner as described above with respect to the reference electricity quantity S7, and as a result, inspection is performed by confirming whether or not the determination section 9 operates.

On the other hand, when the magnitude of the reference electricity quantity S7 of the reference quantity output circuit 8 is changed to S7' in order to change the relay operation setting value, the inspection input S4
The magnitude of is also changed in setting S4' through the amplifier circuit 10 in conjunction with the magnitude corresponding to the magnitude of the reference electric quantity S7' whose setting has been changed. As described above, since the magnitude of the inspection input S3 is set to be slightly larger than the relay operation setting value, the inspection input S3 is introduced into the determination unit 9 at the time of inspection.
Even if the relay operation setting value is changed, the value is always slightly larger than the reference electricity quantity S7, and accurate relay operation can be checked.

In this way, the switching circuit 6 switches between the voltage electricity quantity S ₀ ' of the power system and the inspection input S4, and the reference quantity output sends out the reference electricity quantity S7 corresponding to the magnitude of the relay operation setting value whose setting can be changed. A circuit 8, a determination unit 9 that performs a relay determination by comparing the magnitude of the output S6 of the switching circuit 6 and the output S7 of the reference amount output circuit 8, and a determination unit 9 that makes a relay determination by comparing the magnitude of the output S6 of the switching circuit 6 and the output S7 of the reference amount output circuit 8, and a determination section 9 that makes a relay determination by comparing the magnitude of the output S6 of the switching circuit 6 and the output S7 of the reference amount output circuit 8; An overvoltage relay device is constructed from an amplifier circuit 10 that sets a large value to a large value and sends it out as the above-mentioned inspection input S4, so that the magnitude of the inspection input S4 changes in accordance with the setting change of the relay operation setting value. It is.

Therefore, since the magnitude of the inspection input S4 at the time of inspection is always a slightly larger value than the reference electricity quantity S7, that is, the relay operation setting value, the inspection input is also required when changing the setting of the reference electricity quantity S7, that is, the relay operation setting value. The relay operation can be accurately inspected without changing the setting each time, and its reliability can be improved. Further, when changing the relay operation setting value, there is no need to change the resistance value as in the conventional case, and the troublesome handling can be solved. Furthermore, since it is only necessary to provide the amplifier circuit 10 in place of the inspection circuit 5, which has a complicated configuration, the circuit configuration becomes simple and is extremely advantageous economically.

Next, a second embodiment of the present invention will be described. FIG. 3 is a block diagram showing the configuration of the overvoltage relay device, and the same parts as those in FIG. 2 are given the same reference numerals and their explanations are omitted, and only the different parts will be described here. In other words, in addition to FIG. 2, FIG. 3 uses the output S7 of the reference amount output circuit 8 as an input,
An attenuation circuit 11 is provided to obtain a second inspection input S8 whose magnitude is attenuated by a certain ratio, and the output S8 is
is added to the switching circuit 6. This attenuation circuit 11 outputs S8
is used to attenuate the reference electrical quantity S7 to a value slightly smaller than the relay operation setting value. In addition, inspection input S4 in the switching circuit 6,
The switching of S8 is performed by an inspection command S5 given at each inspection step.

With such a configuration, during inspection, the first inspection input S4, which has a value slightly larger than the relay operation setting value, and the second inspection input S4, which also has a slightly smaller value than the relay operation setting value, are used as inspection inputs. The inspection input S8 is sequentially given to the determination section 9 according to the inspection step. The magnitude of each of these inspection inputs S4 and S8 is determined by the reference amount output circuit 8.
Since it changes in conjunction with the magnitude corresponding to the magnitude of the reference electric quantity S7, it is possible to accurately check both the "operation" and "non-operation" of the relay. Therefore, in this embodiment, in addition to the effects of the first embodiment, the inspection range is expanded and the inspection function is improved.

Next, a third embodiment of the present invention will be described. FIG. 4 shows the configuration of the overvoltage relay device, and the same parts as in FIG. 2 are designated by the same reference numerals. That is, FIG. 4 shows a configuration in which a digital arithmetic processing device such as a microcomputer, the details of which will be described later, is used as the determination section 9'. Further, in the figure, a reference quantity output circuit _8D is for sending out a digital reference quantity of electricity _S7D . 12 is the above reference electric quantity S7 which is a digital quantity.
A digital-to-analog conversion circuit (hereinafter referred to as a D/A conversion circuit) that receives _D as an input converts the input into an analog quantity and uses it as an inspection input S9 in the switching circuit 6
It is added to. Note that this D/A conversion circuit 12 is configured to convert the reference electrical quantity _S7D so that the magnitude of its output S9 becomes a value slightly larger than the relay operation setting value. Note that the reference amount output circuit _8D may be configured with a digital switch, a rotary switch, or the like.

FIG. 5 shows the circuit configuration of the determination section 9'.
In the figure, reference numeral 91' inputs the output S6 of the switching circuit 6, and inputs it to a digital quantity S9 proportional to the output S6.
This is an analog-to-digital converter (hereinafter referred to as an A/D converter) that converts the signal into 1'. Reference numeral 92' denotes a digital arithmetic processing section which receives the output S91' of the A/D converter 91' and the reference electric quantity _S7D as input, and has a built-in regular arithmetic program and an inspection arithmetic program, respectively. This digital calculation processing section 92'
Normally, relay determination is performed by calculation processing based on a regular calculation program, and when inspection command S5 is applied, switching is made to the inspection calculation program, and relay determination is performed by calculation processing based on the inspection calculation program.

In this configuration, the system input S ₀ ′, which is converted into a predetermined amount of electricity from the switching circuit 6 through the input transformer 7, is normally sent to the A/D converter 9 in the determination unit 9′.
1', and here it is converted into a digital quantity S91' proportional to it, which is then introduced into the digital arithmetic processing section 92'. Then, this digital calculation processing section 92' calculates the magnitude of the reference electricity quantity _S7D applied from the reference quantity output circuit _8D and the output S91' of the A/D conversion section 91' based on the commonly used calculation program. A relay determination is made by performing arithmetic processing and comparing the results.

Next, at the time of inspection, input switching is performed by applying an inspection command S5 to the switching circuit 6, and the output _S7D of the reference amount output circuit _8D is sent to the D/A conversion circuit 12.
The inspection input S9, which is converted into an analog quantity and multiplied by a certain value, is then applied to the digital arithmetic processing section 92' of the determination section 9' through the same process as described above. On the other hand, in this digital arithmetic processing section 92', the arithmetic program is switched to the inspection arithmetic program by the application of the inspection command S5. As a result, the digital calculation processing section 9
In step 2', the magnitude of the reference electrical quantity _S7D and the output 91' of the A/D converter 91' are compared by performing arithmetic processing based on the inspection arithmetic program, and a relay judgment is made. . In addition, in this case, as the inspection input S9, the reference amount output circuit 8 is used as described above.
Since the reference electricity quantity S7 of _D changes in conjunction with _D and has a value slightly larger than the relay operation setting value is constantly applied to the judgment section 9', it is possible to check whether or not the relay operation judgment is performed correctly. Can be inspected accurately. Therefore, in addition to the effects of the above-mentioned embodiments, this embodiment can be applied to a wider variety of relays, that is, it can be applied to digital relay devices as well.

Next, a fourth embodiment of the present invention will be described. FIG. 6 shows the configuration of the overvoltage relay device. The same parts as those in FIG. 4 are given the same reference numerals, and the explanation thereof will be omitted, and only the different parts will be described here. In other words, in addition to FIG. 4, FIG. 6 uses the output reference electric quantity S7 _D of the reference quantity output circuit 8 _D as input,
Converting it into an analog quantity and obtaining a second inspection input S10 whose magnitude is attenuated by a certain value D/
An A conversion circuit 13 is provided, and its output S10 is applied to the switching circuit 6. This D/A conversion circuit 13 converts the reference electric quantity _S7D so that its output S10 becomes a value slightly smaller than the relay operation setting value. In addition, the inspection input S9 in the switching circuit 6,
The switching in S10 is performed by an inspection command S5 given at each inspection step.

With such a configuration, during inspection, the first inspection input S9, which has a value slightly larger than the relay operation setting value, and the second inspection input S9, which also has a slightly smaller value than the relay operation setting value, are used as inspection inputs. The inspection input S10 is sequentially applied to the determination section 9' according to the inspection step. Since the magnitude of each of these inspection inputs S9 and S10 changes in conjunction with the magnitude of the reference electrical quantity _S7D of the reference quantity output circuit _8D , the "operation" of the relay changes.
and “non-operation” inspections can be performed accurately. Therefore, in this embodiment, in addition to the effects of the third embodiment, the inspection range is expanded and the inspection function is improved.

Next, a fifth embodiment of the present invention will be described. FIG. 7 shows the configuration of the overvoltage relay device in block form, and the same parts as in FIG. 4 are designated by the same reference numerals. In the figure, 9'' is a determination unit whose circuit configuration is exactly the same as that shown in FIG.
The output S applied via the A/D converter 91'
91' and the above-mentioned reference electricity quantity _S7D are input, and a regular calculation program and an inspection program are built in, respectively, as described above, but in addition, when the inspection command S5 is applied during inspection, the The difference is that a calculation processing function is provided to output two types of inspection inputs S11 having different values as digital quantities based on the reference electric quantity _S7D according to the inspection step. On the other hand, in the figure, 14 is a D/A conversion circuit that receives the inspection input S11 output from the digital arithmetic processing section 92'', and converts it into an analog quantity and outputs the inspection input S11.
It is configured to be added to the switching circuit 6 as a. Here, in the above two types of inspection inputs S11 having different values, the determination unit 9'' is the reference electricity amount S7 _D
The output is slightly larger and the output is slightly smaller than the relay operation setting value when relay judgment is performed by introducing .

With such a configuration, at the time of inspection, an inspection input that is slightly larger than the relay operation setting value or an inspection input that is slightly smaller than it is applied to the determination unit 9'' depending on the inspection step, In addition, since the magnitude of the inspection input S11 is changed in conjunction with the magnitude of the reference electrical quantity _S7D of the reference quantity output circuit _8D , the relay's "operation" and "non-operation" can be changed. Both determination functions can be checked accurately, and the same effects as in the second and fourth embodiments can be obtained.

Next, a sixth embodiment of the present invention will be described. FIG. 8 shows the configuration of the overvoltage relay device, and the same parts as in FIG. 4 are designated by the same reference numerals. In other words, the difference between FIG. 8 and FIG. 4 is that the switching circuit 6' receives a plurality of electric quantities of the power system, for example, voltages S _R , S _S , _ST corresponding to each of the three phases of the power system.
The input transformers 7 _R , 7 _S , and 7 _T are configured to introduce the inputs S _R ′, S _S ′, and S _T ′ by a switching signal S13 as an input selection signal, which will be described later. The output can be switched. Further, the circuit configuration of the determining section 9 is the same as that shown in FIG. 4, but the function of the digital arithmetic processing section 92 is different. That _is , in addition to the functions described in FIG. ₄ , a switching signal (for example, " ₀₀ ”, “01”,
S13 (corresponding to "10" and "11") is provided with a function to be given to the switching circuit 6'. In other words, normally three types of switching signals S13, "00", "01", and "10" are sequentially sent out cyclically, while when the inspection command S5 is applied, "11" is sent out as switching signals S13, respectively. It is composed of

In this configuration, the switching signal S13 is normally sent from the determination unit 9 to the switching circuit 6' as "00", "01",
A value of “10” is given to each cycle in sequence. As a result, in the switching circuit 6', the switching signal S1
3, and each phase voltage S applied through each input transformer 7 _R , 7 _S , 7 _T
R ′, S _S ′, and S _T ′ are sequentially cyclically output S
6' is added to the determination unit 9. In this determination section 9, the output S of the switching circuit 6'
6' and the reference electric quantity _S7D of the reference quantity output circuit _8D are compared by performing arithmetic processing based on a commonly used arithmetic program, and a relay determination is made.

Next, at the time of inspection, an inspection command S5 is given to the determination section 9, so that the calculation program is switched to the inspection calculation program, and the switching signal S13 is applied as "11" to the switching circuit 6'. Then, the switching circuit 6' performs input switching based on the switching signal S13, and the output reference electric quantity _S7D of the reference quantity output circuit _8D is changed from this to the inspection input S9 obtained through the D/A conversion circuit 12. It is added to the determination section 9 as an output S6'.
As a result, the determination section 9 performs arithmetic processing based on the inspection program to compare the magnitudes of the reference electricity quantity _S7D and the output S6' of the switching circuit 6', and the relay determination is performed correctly. It is checked whether or not.

Therefore, with such a configuration, in addition to the effects of the third embodiment, it is possible to obtain effects that can be similarly applied to a miniaturized device in which relay judgment is performed for a plurality of relay inputs by one judgment section. It is something.

In each of the above embodiments, the case of DC inspection was described in which the inspection input was applied from the secondary side of the input transformer, but next, the inspection input was applied from the primary side of the input transformer. An example of the case will be described with reference to the drawings. FIG. 9 shows the configuration of the overvoltage relay device. In the figure,
The switching circuit 6 inputs the grid voltage S ₀ , inspection input S12, and switching signal S14. Normally, the switching circuit 6 receives the grid voltage S ₀ , while during inspection by applying the inspection command S5, the switching signal S14 changes the inspection input S12 to the input transformer. The signal is switched and sent to the determination section 9 as an output S6' via S7'. In addition, the determination unit 9 also outputs an inspection instruction S5 at the time of inspection.
By adding this, the built-in inspection calculation program sends out the switching signal S14 and performs calculation processing based on the switching signal S14.

In such a configuration, since the inspection input S12 is applied from the primary side of the input transformer 7', the above-mentioned DC inspection is impossible and it is necessary to use an AC inspection. The inspection input S12 for this AC inspection can be obtained by controlling the inspection input S11 using the built-in program of the determination unit 9. That is, by changing the magnitude of the inspection input S11 in time series and converting it into an analog quantity through the D/A conversion circuit 14, the inspection input S12 of the alternating current amount can be obtained. The magnitude of this inspection input S12 is determined by the determination unit 9 as a reference electric quantity S.
When relay determination is performed by introducing _7D , the determination unit 9 can control to a value slightly larger or slightly smaller than the relay operation setting value.

FIG. 10 shows an operation time chart for the above configuration. In other words, in the figure, time
When the inspection command S5 is applied to the determination section 9 at _t0 , the switching signal S14 is applied to the switching circuit 6. Then, before time t ₀ , the system voltage S ₀ was sent out from the switching circuit 6 as its output S6, but after time t ₀ , the inspection input S12 is sent out. On the other hand, the inspection input S11 is based on the built-in inspection calculation program of the determination unit 9, and after time _t0 , digital quantity values (0, N, _2N , 3N, ...) is sent. The D/A conversion circuit 14 receives this inspection input S1.
1 to an analog quantity and check input of AC quantity S1
Send as 2. Then, the magnitude of the peak value of the inspection input S12 between time t ₀ and _{t 1} (3N, −3N)
is slightly larger than the relay operation setting value, and the peak value (3M, -3M) of the inspection input S12 between time t ₁ and _{t 2} is slightly smaller than the relay operation setting value. It is set as follows. With this setting, it is possible to check whether the relay is operating correctly or incorrectly using two cycles of inspection input. When the inspection is completed at time _t2 , the switching signal S14 is no longer applied from the determining section 9 to the switching circuit 6, and the switching circuit 6 outputs the system voltage _S0 again.

Therefore, with such a configuration, the reference electricity amount S7 _D
A check input S12 linked to the setting of the relay operation can be applied from the primary side of the input transformer 7', and the value of the check input S12 can also be set to a value slightly larger or smaller than the relay operating setting value. It can also be set to a value, allowing accurate checking of relay operation and non-operation.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be similarly implemented in the following manner.

(1) In each of the above embodiments, an overvoltage relay has been described as an example, but the present invention is not limited to this in any way. For example, in a relay that detects undervoltage in the configuration shown in FIG. 2, an attenuation circuit 11 as shown in FIG. 3 may be used instead of the amplifier circuit 10 to check the operation of the relay. The good news is obvious.

(2) It is also clear that the switching circuit 6' of FIG. 8 described in the sixth embodiment above can be used as the switching circuit 6 in the configurations of FIGS. 4, 6, and 7. be.

(3) In the embodiment configuration shown in Fig. 8 above, when multiple relay elements are used as relay inputs, if multiple reference amount output circuits are provided corresponding to the relay inputs, the same inspection can be performed for each relay element. It is also clear that it is possible to do

(4) In the embodiment configuration shown in FIG. 7 above, the inspection input S11 as a digital quantity outputted from the determination section 9'' is converted into an analog quantity by the D/A conversion circuit 14, and the inspection input S11 is converted into an analog quantity by the D/A conversion circuit 14. However, the means for outputting the inspection input is not limited to this in any way. For example, FIG. 11 shows the configuration of the output circuit for the inspection input. In the input/output circuit 15, the resistors R11 to R1N are connected in series and provided between the power supply bus lines (V _CC , O ^V ).
Each connection point P ₁ to P _N- of each of these resistors R11 to R1N
₁ voltage is introduced into each output selection circuit 15. Then, each voltage value is determined by the reference amount output circuit 8.
Each setting point in _D is set so that the inspection output S12 becomes a value slightly larger than the relay operation setting value when the determination unit introduces the reference electricity amount _S7D . Therefore, when the determination section introduces the reference quantity of electricity _S7D , the inspection input S12 having a value slightly larger than the relay operation setting value in this reference quantity of electricity _S7D is selectively sent out from the output selection circuit 15'. The check signal S15 is given to the output selection circuit 15'.

(5) In the configuration of (4) above, the settings of each resistor R11 to R1N are set so that the inspection input S12 of a value slightly smaller than the relay operation setting value at each setting point of the reference amount _S7D is sent out. It is also possible to do so. In addition, this inspection input S1
2, it is also possible to set each of the resistors R11 to R1N so that both a value slightly larger and a value slightly smaller than the relay operation setting value can be sent out.

(6) In the configuration (4) above, the output selection circuit 1
The inspection input S15 output from the determination section 9 is input as a signal for selecting the output S12 of the 5', but it is also possible to replace this with the reference electric quantity S7 _D , which is a digital quantity. In this case, the D/A conversion circuits 12 and 13 in FIGS. 4, 6, and 8 can be replaced with the configuration shown in FIG. 11.

(7) In the configuration shown in FIG. 11 in (4) above, the selection circuit 15' is used to select the inspection input S12, but the configuration is configured to use a contact that is linked to the setting of the reference amount output circuit _8D . It is okay to do so.

(8) In the third to sixth embodiments described above, the case where the inspection command S5 at the time of inspection is given from the outside has been described, but the inspection command is sent from the determination unit at regular time intervals and processed within the device. The arithmetic program may be configured to obtain the following information.

In addition, the present invention can be modified and implemented in various ways without changing the gist thereof.

As explained above, according to the present invention, there is provided a reference quantity output circuit that outputs a reference quantity of electricity of a magnitude corresponding to a relay operation setting value whose setting can be changed, and a reference quantity of electricity from this reference quantity output circuit. , an inspection input output means that outputs an inspection input that changes in accordance with the magnitude of the reference electricity quantity, and an inspection input from this inspection input output means and the electricity quantity of the electric power system to be protected, and constantly inputs the amount of electricity in the power system, and a switching circuit that switches and outputs the inspection input when an inspection command is applied, the output from this switching circuit, and the reference amount of electricity from the reference amount output circuit, and calculates the magnitude relationship between the two. Since it is equipped with a judgment means for comparing and making a relay judgment, there is no need to change the setting of the inspection input even when changing the setting of the above-mentioned operation setting value, and accurate inspection can be performed with a simple circuit configuration. It is possible to provide a protective relay device with extremely high reliability.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a conventional protective relay device, Fig. 2 is a configuration block diagram showing an embodiment of the present invention, and Fig. 3 is a diagram showing a conventional protective relay device.
4 and 6 to 11 are diagrams showing other embodiments of the present invention, and FIG. 5 is a block diagram showing the configuration of the determination section in FIG. 4. 6, 6'... switching circuit, 7, 7'... input transformer,
9,9'-9...Judgment section, 8,8 _D ...Reference amount output circuit, 10...Amplification circuit, 11...Attenuation circuit, 12,1
3, 14...D/A conversion circuit, 15...Inspection output circuit, 15'...Output selection circuit, 91'...A/D conversion section, 92'...Digital calculation processing section, R11-R1
N...Resistance.

Claims (1)

[Claims] 1 Relay operation whose setting can be changed A reference quantity output circuit that outputs a reference quantity of electricity corresponding to the set value, and a reference quantity of electricity from this reference quantity output circuit as input, and follows the size of the reference quantity of electricity. An inspection input/output means outputs an inspection input that changes based on the input, and the inspection input from this inspection input/output means and the amount of electricity of the power system to be protected are input, and the amount of electricity of the power system is always output as an inspection command. a switching circuit that switches and outputs the inspection input when the voltage is applied; and a determining means that inputs the output from this switching circuit and the reference quantity of electricity from the reference quantity output circuit, and compares the magnitude relationship between the two to make a relay judgment. A protective relay device comprising: