JP2010259169A - Protective relay device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective relay device which allows early parallel-off of an electric installation and quick restoration of a power system without complicating the configuration of the device. <P>SOLUTION: The protective relay device is applied to an electric installation connected to a power system and including at least one generator. In the electric installation 6, there are provided an undervoltage relay 11 that detects a voltage drop at a point of linkage with the power system and a V/F relay 12 that detects V/F at the point of linkage. When the undervoltage relay 11 detects voltage drop at the point of linkage and V/F detected by the V/F relay 12 is normal, the protective relay device disconnects the linkage between the power system and the electric installation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a protective relay device applied to electrical equipment connected to a power system.

  Conventionally, it is a device applied to electrical equipment connected to the power system, for example, provided with means for disconnecting the electrical equipment from the power system when an accident occurs on the power system side and the power system side becomes a non-powered state There was a device called an isolated operation detection device (for example, Patent Document 1).

  The technique shown in this Patent Document 1 periodically gives a sway signal to the generator, and this sway signal is absorbed into the generator output by the synchronization power on the power system side when connected to the power system, This is an application of the fact that it appears as a generator output when the power system is in a non-powered state. Note that, as in Patent Document 1, a device that actively detects an isolated operation by giving a shaking signal to the generator side is called an active isolated operation detection device or an active isolated operation prevention device. ing.

  On the other hand, devices that do not use such a complicated method include a device that eliminates the interconnection with the power system by operating signals from a ground fault overvoltage relay, undervoltage relay, short-circuit direction relay, underfrequency relay, etc. (For example, Patent Document 2).

  In addition, the electric equipment which the said patent documents 1, 2 assumes is an electric equipment in which the generator is installed in the electric equipment premise, for example. For such electrical equipment, that is, electrical equipment that may supply power from the premises to the power system side when the power system becomes unpowered, installation requirements and technical requirements are stipulated. (For example, Non-Patent Document 1).

JP-A-7-31197 JP-A-9-275638

Grid interconnection rules Grid-interconnection Code JEAC 9701-2006, Japan Electric Association Grid interconnection specialist group (Ohm), pp14, 66, 67, 72, 73, 122-125, 138-141

  However, since the above Patent Documents 1 and 2 do not require immediate disconnection of electrical equipment, there are restrictions such as cooperation with protection on the power system side (accident removal in the power system) and safe stop of the generator. The operation time was from several hundred milliseconds to several seconds. Therefore, during this operation time period, the form of supplying electric power from the electric facility premises to the electric power system side continues.

  On the other hand, recovery (recovery operation) from the power system side is required to be quick, and during power recovery, the internal phase angle of the generator and motor in the electrical equipment and the voltage phase angle on the power system side If there is a phase difference greater than a certain value, there is a possibility of damage to the equipment, so an early disconnection of the electrical equipment was necessary.

  In addition, the active isolated operation prevention device represented by Patent Document 1 requires a complicated control circuit, and thus has a drawback that the device is enlarged.

  Moreover, in the conventional methods according to Patent Documents 1 and 2 described above, power is supplied to the power system in spite of the state where the power generation capacity and the load in the electrical equipment should be balanced. There were also drawbacks such as the loss of balance.

  The present invention has been made in view of the above, and provides a protective relay device that enables early disconnection of electrical equipment and quick restoration of a power system without complicating the configuration of the device. For the purpose.

  In order to solve the above-described problems and achieve the object, a protective relay device according to the present invention is connected to an electric power system and applied to an electrical facility including at least one generator. In the electrical equipment, there are an undervoltage detection unit that detects a voltage drop at a connection point with the power system, and a V / F detection unit that detects a voltage frequency ratio (V / F) at the connection point. The power system and the electrical equipment when the undervoltage detection unit detects a voltage drop at the interconnection point and the voltage frequency ratio detected by the V / F detection unit is normal. It is characterized by cutting off the connection with.

  According to the protective relay device according to the present invention, it is possible to provide a protective relay device that enables early disconnection of electrical equipment and quick restoration of the power system without complicating the configuration of the device. There is an effect.

FIG. 1 is an overall configuration diagram of a power system including electrical equipment to which the protective relay device according to the first embodiment is applied. FIG. 2 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit) applied in the protective relay device according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit) applied in the protective relay device according to the second embodiment. FIG. 4 is a diagram illustrating an example of a connection configuration of an undervoltage relay and a V / F relay in the third embodiment. FIG. 5 is an overall configuration diagram of an electric power system including electric equipment to which the protective relay device according to the fourth embodiment is applied. FIG. 6 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit and generator cutoff signal generation circuit) applied in the protective relay device according to the fourth embodiment. FIG. 7 is a diagram illustrating a configuration of a logic circuit (a connection point cutoff signal generation circuit and a generator cutoff signal generation circuit) applied in the protective relay device according to the fifth embodiment. FIG. 8 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit and generator cutoff signal generation circuit) applied in the protective relay device according to the sixth embodiment of the present invention. FIG. 9 is a diagram illustrating a configuration of a logic circuit (a connection point cutoff signal generation circuit and a generator cutoff signal generation circuit) applied in the protective relay device according to the seventh embodiment of the present invention. FIG. 10: is a partial block diagram in the electric power grid | system including the electrical installation with which the protective relay apparatus concerning Embodiment 8 of this invention is applied. FIG. 11: is a partial block diagram in the electric power grid | system including the electrical installation with which the protection relay apparatus concerning Embodiment 9 of this invention is applied.

  Hereinafter, a protective relay device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

Embodiment 1 FIG.
FIG. 1 is an overall configuration diagram of a power system including electrical equipment to which a protective relay device according to a first embodiment of the present invention is applied. In FIG. 1, both the electrical equipment 6 in which the generator 15 is installed and the electrical equipment 7 in which no generator is installed are connected to the substations 1 and 5 of the power system via the transmission line 3. The substations 1 and 5 are respectively provided with sending circuit breakers 2 and 4 for shutting off in the event of a power transmission line accident, as well as an electrical installation 6 where a generator is installed and an electrical installation 7 where no generator is installed. The interconnection point breaker 8 as the first breaker is provided at each interconnection point with the power system.

  The electrical facility 6 includes a power receiving point bus 9 for power distribution connection, and includes a load 17 and a generator 15 connected from the power receiving point bus 9 via a transformer 16 in the electrical facility. In addition, the generator 15 is the structure connected to the transformer 16 in an electrical installation via the connection point circuit breaker 14 which is a 2nd circuit breaker.

  An undervoltage relay 11 and a V / F relay 12 are connected to the power receiving point bus 9 via an instrument transformer 10. Here, the V / F relay 12 is a relay that compares the voltage / frequency ratio (voltage frequency ratio) with a set value.

  In addition, the thick line arrow schematically shown in FIG. 1 represents the interruption signal (interconnection point interruption signal) 13 output from the undervoltage relay 11 and the V / F relay 12 to the interconnection point breaker 8. ing.

  Moreover, the structure by which the load 18 which is another electric equipment is connected to the electric equipment 7 which is not connected to the generator is shown.

  FIG. 2 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit) applied in the protective relay device according to the first embodiment of the present invention. As shown in FIG. 2, the output of the undervoltage relay 11 is input to one input terminal of the AND circuit 19 with a negative terminal, and the output of the V / F relay 12 is the other input terminal of the AND circuit 19 with a negative terminal. (Negative terminal) is input, and the output of the AND circuit with the negative terminal is the connection point cutoff signal 13.

  Next, the operation of the protective relay device according to the first embodiment will be described. Here, first, a brief description of the phenomenon described in the paragraph “0008” of the background art will be given.

  Assume that an accident occurs in the transmission line 3 of the power system. At this time, the power transmission line breakers 2 and 4 provided in the substations 1 and 5 are interrupted by the protective relay (not shown) installed in the substations 1 and 5. On the other hand, the substations 1 and 5 turn on the power transmission line breakers 2 and 4 after a certain time to re-apply (reclose) the power transmission line 3. Therefore, if the accident of the power transmission line 3 is restored at the time of reapplying power, power is supplied (recovered) to the electrical equipment connected as it is. In the period until the power transmission line 3 is reclosed, the electric facilities 6 and 7 remain connected to the power transmission line 3.

  Here, for example, when there is a generator in the facility as in the electrical facility 6, in this state, the accident current is supplied to the transmission line 3, the accident is minor, and after the natural disappearance, In some cases, power is supplied to other electrical equipment. In the latter case, among the devices connected to the power system, motors that are rotating with a load connected, etc., quickly stall due to voltage drop and stop automatically, etc., while the power generation and load of the generator And a balance is established between a constant power generation and a constant load, and operation may continue at a low frequency despite a voltage drop state.

  Note that the operating state as described above is an abnormal state for the generator, but only the frequency is low, and there is no other abnormality such as overexcitation. On the other hand, since this operation state is an operation in an area where the generator protection is necessary to avoid mechanical damage, the generator is necessarily stopped at a low speed according to the mechanical tolerance of the generator. As a result, the power application state may be long (several seconds or more).

  If re-closing is performed on the power system side in this operating state, power is restored in the state where the frequency difference and phase difference are generated, and excessive stress is applied to the generator. It is necessary to increase the time.

  Thus, when the generator is in a normal state, detecting that the voltage is in an abnormal state and thereby disconnecting the connection with the power system is the gist of the protective relay device in this embodiment. It is.

  Returning to FIG. 1, the description of the operation of the protective relay device will be continued. Even when the sending circuit breakers 2 and 4 of the substations 1 and 5 are opened, the electrical equipment 6 and the electrical equipment 7 are in an electrically connected state via the power transmission line 3. In this state, the generator 15 supplies necessary power to the load 17 in its own electrical equipment 6 and the load 18 in the electrical equipment 7. Depending on the situation, the generator 15 generally does not have the ability to supply rated power to the loads 17 and 18. However, when the voltage drops and the loads 17 and 18 are, for example, constant resistance loads, there may be a balance between supply and demand. At this time, although the generator 15 is in a state where the frequency is lowered as described above, it is normal in terms of excitation. Therefore, the V / F relay 12 does not operate because the frequency ratio to the voltage is within the specified range, and the undervoltage relay 11 operates because the voltage is reduced.

  When the undervoltage relay 11 operates and the V / F relay 12 does not operate, the logical product 19 with a negative terminal becomes “true”, and the connection point cutoff signal 13 is output. In addition, the connection point breaker 8 is cut off by the connection point cut-off signal 13, and the power source connected to the power transmission line 3 is lost. Therefore, the power transmission line 3 is in a completely non-powered state.

  Here, according to the technical matter described in the “system interconnection regulations” that is Non-Patent Document 1 described above, it is essential to operate the undervoltage relay. Therefore, when the operation in a state where supply and demand is balanced as described above continues, the electrical equipment 6 will eventually be disconnected from the power system.

  However, the decisive difference between the protective relay device that complies only with the “system interconnection regulations” and the protective relay device of the first embodiment is the difference in the time during which the power transmission line 3 is in a completely non-powered state. is there. That is, according to the protective relay device of the first embodiment, disconnection from the power system is possible after a transient confirmation time, whereas in the protective relay device that only complies with the “system interconnection regulations”, The disconnection from the power system is delayed.

  As described above, according to the protective relay device of the first embodiment, when the power transmission line 3 is in a non-powered state and the generator 15 is in an operating state at a low voltage and a low frequency, the generator 15 is installed. It is possible to quickly disconnect the existing electrical equipment 6 from the transmission line 3.

Embodiment 2. FIG.
In the first embodiment, it is assumed that the load capacities of the loads 17 and 18 are larger than the rated power of the generator 15. However, the second embodiment is different from the first embodiment in that the generator It is assumed that the rated power of 15 is larger than the load capacity of the loads 17 and 18, and FIG. 3 shows the configuration of a logic circuit (interconnection point cutoff signal generation circuit) corresponding to this embodiment. Specifically, in FIG. 3, instead of the undervoltage relay 11 of FIG. 2, an overvoltage relay 20 is connected to the AND circuit 19 with a negative terminal.

  Next, the operation of the protective relay device according to the second embodiment will be described. In the first embodiment, since the rated power of the generator 15 is smaller than the load capacity of the loads 17 and 18, the voltage is lowered and the supply and demand balance is shown. On the other hand, when the rated power of the generator 15 is larger than the load capacity of the loads 17 and 18, the voltage rises and the supply and demand balance is achieved. For this reason, in a state where supply and demand are balanced, the overvoltage relay 20 operates and the V / F relay 12 does not operate. At this time, the AND circuit 19 with a negative terminal becomes “true”, and the connection point cutoff signal 13 is output. In addition, the connection point breaker 8 is cut off by the connection point cut-off signal 13, and the power source connected to the power transmission line 3 is lost. Therefore, the power transmission line 3 is in a completely non-powered state.

  As described in the first embodiment, even if the protection relay device complies only with the “system interconnection regulations”, the electrical equipment 6 is disconnected from the power system after a certain amount of time has elapsed. However, when the protection relay device that complies only with the “system interconnection regulations” and the protection relay device of the second embodiment are compared, there is a great difference in the time for which the power transmission line 3 is in a completely non-powered state. In other words, according to the protective relay device of the second embodiment, disconnection from the power system is possible after a transient confirmation time, whereas in the protective relay device that only complies with the “system interconnection regulations”, The disconnection from the power system is delayed.

  As described above, in the protective relay device of the second embodiment, when the power transmission line 3 is in a non-powered state and the generator 15 is in an overvoltage and overfrequency operation state, the electrical equipment in which the generator 15 is installed. 6 can be quickly disconnected from the transmission line 3.

Embodiment 3 FIG.
In the first embodiment, the protective relay device including the undervoltage relay 11 and the V / F relay 12 has been described, but no reference is made to the number of phases in which the protective relay device is provided. In the “system interconnection regulations”, the number of phases is determined on the basis of three phases in order to ensure detection. Therefore, in the protective relay device of the third embodiment, the undervoltage relay 11 and the V / F relay 12 are used in different phases in order to implement the equivalent function required by the “system interconnection regulations”. A configuration in which one type of relay produces the same effect as using another phase is disclosed. In addition, the structure shown in FIG. 4 shows the example, the undervoltage relay 11 is arrange | positioned in ab phase, and the V / F relay 12 is arrange | positioned in bc phase.

  Next, the operation of the protective relay device according to the third embodiment will be described. In FIG. 4, when there is an abnormality in the phase a of the instrument transformer 10, the V / F relay 12 does not detect an abnormality, whereas the undervoltage relay 11 detects an abnormality. Further, when there is an abnormality in the phase b of the instrument transformer 10, both the V / F relay 12 and the undervoltage relay 11 detect the abnormality. Further, when there is an abnormality in the c phase of the instrument transformer 10, the undervoltage relay 11 does not detect an abnormality and the V / F relay 12 detects an abnormality, contrary to the case of the a phase.

  Thus, according to the protective relay device of the third embodiment, since each phase can be detected without installing each relay in all phases, without complicating the device configuration, Early disconnection of electrical equipment and quick restoration of the power system are possible.

  In the present embodiment, the configuration in which the phases used in the undervoltage relay and the V / F relay are different is illustrated, but the phase used in the overvoltage relay and the V / F relay may be different. It is possible and the same effect as this embodiment can be obtained.

Embodiment 4 FIG.
FIG. 5 is an overall configuration diagram of a power system including electrical equipment to which the protective relay device according to the fourth embodiment of the present invention is applied. The difference from FIG. 1 is that a generator cutoff signal 21 indicated by a thick arrow is added. That is, FIG. 5 shows an embodiment in which the connection point break signal 13 is output toward the connection point breaker 8 and the generator break signal 21 is output toward the connection point breaker 14.

  FIG. 6 is a diagram illustrating a configuration of a logic circuit (a connection point cutoff signal generation circuit and a generator cutoff signal generation circuit) applied in the protection relay device according to the fourth embodiment of the present invention. As shown in FIG. 6, the output of the undervoltage relay 11 is input to one input terminal of the AND circuit 19 with a negative terminal, and the output of the V / F relay 12 is the other input terminal of the AND circuit 19 with a negative terminal. (Negative terminal) is input, and the output of the AND circuit with the negative terminal is the connection point cutoff signal 13.

  Further, the output of the AND circuit 19 is input to one input terminal of the AND circuit 22, the connection point cutoff signal 13 is input to the other input terminal of the AND circuit 22, and the output of the AND circuit 22 generates power. The machine shutoff signal 21 is obtained.

  Next, the operation of the protective relay device according to the fourth embodiment will be described. In addition, the operation | movement until it interrupts | blocks the connection point circuit breaker 8 is the same as that of Embodiment 1, and abbreviate | omits description. When the connection point break signal 13 is output and the connection point breaker 8 is turned off, the electrical equipment 6 is disconnected from the power transmission line 3 of the power system. Electric power is supplied to the load 17 in the facility 6. In addition, the power source connected to the power transmission line 3 disappears, and the power transmission line 3 is in a completely non-powered state.

  At this time, if the states of the undervoltage relay 11 and the V / F relay 12 do not change, the operation output of the AND circuit 19 with a negative terminal continues, so the condition of the AND circuit 22 is satisfied and the generator cutoff signal 21 Is output. That is, if the state of the undervoltage relay 11 and the V / F relay 12 does not change after the connection point cutoff signal 13 is output, the generator cutoff signal 21 is output following the output of the connection point cutoff signal 13. Will be.

  In addition, as a prior art which disclosed the technique regarding generator protection, there exists "the Institute of Electrical Engineers technical report 898", for example (henceforth Nonpatent literature 2). According to Non-Patent Document 2, since the generator has an excitation loss that increases with respect to an overvoltage or a frequency drop, the V / F is measured, and control that does not exceed the tolerance of the generator based on the measured V / F. Is described as being possible. Therefore, if the undervoltage relay 11 operates and the V / F relay 12 operates, the generator 15 will eventually be stopped.

  However, the decisive difference between the protective relay device to which the technique of Non-Patent Document 2 is applied and the protective relay device of the fourth embodiment is the difference in time for determining the disconnection of the generator 15. That is, according to the protective relay device of the fourth embodiment, the control of stopping the operation of the generator after the transient confirmation time is possible, whereas the protective relay device to which the technique of Non-Patent Document 2 is applied. Then, the control for stopping the operation of the generator is delayed.

  As described above, according to the protective relay device of the fourth embodiment, when the transmission line 3 is in the non-feed state and the generator 15 is in the operation state at the low voltage and the low frequency, the operation of the generator 15 is performed. It becomes possible to stop immediately.

  In the present embodiment, the connection breaker 14 is shut off when the operation of the generator 15 is quickly stopped, but the present invention is not limited to this control. For example, a control signal may be output to another control device (not shown) that can quickly stop the operation of the generator 15, and the same effect as in the present embodiment can be obtained.

Embodiment 5 FIG.
In the fourth embodiment, it is assumed that the load capacity of the loads 17 and 18 is larger than the rated power of the generator 15 after the electrical equipment 6 is disconnected from the power system. In contrast to the fourth embodiment, it is assumed that the rated power of the generator 15 is larger than the load capacity of the loads 17 and 18, and a logic circuit (interconnection point cutoff signal generation circuit corresponding to the present embodiment). FIG. 7 shows the configuration of the generator cutoff signal generation circuit). Specifically, in FIG. 7, instead of the undervoltage relay 11 of FIG. 6, an overvoltage relay 20 is connected to the AND circuit 19 with a negative terminal.

  Next, the operation of the protective relay device according to the fifth embodiment will be described. In the fourth embodiment, since the rated power of the generator 15 is smaller than the load capacity of the loads 17 and 18, the voltage is reduced, and the supply and demand balance is shown. On the other hand, when the rated power of the generator 15 is larger than the load capacity of the loads 17 and 18, the voltage rises and the supply and demand balance is achieved. For this reason, in a state where supply and demand are balanced, the overvoltage relay 20 operates and the V / F relay 12 does not operate. At this time, the AND circuit 19 with a negative terminal becomes “true”, and the connection point cutoff signal 13 is output. In addition, the connection point breaker 8 is cut off by the connection point cut-off signal 13, and the power source connected to the power transmission line 3 is lost. Therefore, the power transmission line 3 is in a completely non-powered state.

  At this time, if the state of the overvoltage relay 20 and the V / F relay 12 does not change, the operation output of the AND circuit 19 with a negative terminal continues, so the condition of the AND circuit 22 is satisfied and the generator cutoff signal is satisfied. 21 is output. That is, if the state of the overvoltage relay 20 and the V / F relay 12 does not change after the connection point cutoff signal 13 is output, the generator cutoff signal 21 is output following the output of the connection point cutoff signal 13. As a result, the operation of the generator 15 can be promptly stopped.

  As described above, according to the protective relay device of the fifth embodiment, when the power transmission line 3 is in a non-powered state and the generator 15 is in an overvoltage and overfrequency operation state, the operation of the generator 15 is quickly performed. It becomes possible to stop.

  In the present embodiment, the connection breaker 14 is shut off when the operation of the generator 15 is quickly stopped, but the present invention is not limited to this control. For example, a control signal may be output to another control device (not shown) that can quickly stop the operation of the generator 15, and the same effect as in the present embodiment can be obtained.

  Moreover, although the said Embodiment 4, 5 demonstrated the case where the operation state before and after the electrical installation 6 was disconnected from an electric power grid | system was continued, it is not limited to those operation states, The electrical installation 6 May be different from the phenomenon that causes the electrical facility 6 to be disconnected from the power system and the phenomenon after the electrical facility 6 is disconnected from the power system. That is, the control of the fifth embodiment may be performed after the control of the first embodiment is performed, and conversely, the control of the second embodiment is performed after the control of the second embodiment is performed. The control may be performed.

Embodiment 6 FIG.
FIG. 8 is a diagram illustrating a configuration of a logic circuit (interconnection point cutoff signal generation circuit and generator cutoff signal generation circuit) applied in the protective relay device according to the sixth embodiment of the present invention. The difference from the logic circuit of the fourth embodiment shown in FIG. 6 is that the AND circuit 22 is omitted. That is, the logic circuit of the sixth embodiment is configured such that the generator cutoff signal 21 is output simultaneously with the output of the interconnection point cutoff signal 13.

  Next, the operation of the protective relay device according to the sixth embodiment will be described. The movement until the connection point breaker 8 is shut off is the same as that in the fourth embodiment, and the description thereof is omitted.

  On the other hand, the protective relay device of the sixth embodiment is configured such that the generator cutoff signal 21 is output simultaneously with the output of the connection point cutoff signal 13, so that the electrical equipment 6 is disconnected from the transmission line 3. In addition, the stop control of the generator 15 is performed immediately.

  Therefore, according to the protective relay device of the sixth embodiment, compared with the protective relay device of the first to fifth embodiments, the stop control of the generator 15 after the power transmission line 3 is in a non-powered state is more performed. The effect that it can be performed rapidly is acquired.

  In the present embodiment, the connection breaker 14 is shut off when the operation of the generator 15 is quickly stopped, but the present invention is not limited to this control. For example, a control signal may be output to another control device (not shown) that can quickly stop the operation of the generator 15, and the same effect as in the present embodiment can be obtained.

Embodiment 7 FIG.
In the sixth embodiment, it is assumed that the load capacities of the loads 17 and 18 are larger than the rated power of the generator 15, but the seventh embodiment is contrary to the sixth embodiment. It is assumed that the rated power of 15 is larger than the load capacity of the loads 17 and 18, and the configuration of the logic circuit (interconnection point cutoff signal generation circuit and generator cutoff signal generation circuit) corresponding to the present embodiment is configured. It is shown in FIG. Specifically, in FIG. 9, instead of the undervoltage relay 11 of FIG. 8, an overvoltage relay 20 is connected to the AND circuit 19 with a negative terminal.

  Next, the operation of the protective relay device according to the seventh embodiment will be described. In the sixth embodiment, the control mode in which both the connection point cutoff signal 13 and the generator cutoff signal 21 are output when the undervoltage relay 11 operates and the V / F relay 12 does not operate is shown. In the seventh embodiment, when the overvoltage relay 20 operates and the V / F relay 12 does not operate, both the connection point cutoff signal 13 and the generator cutoff signal 21 are output.

  Therefore, according to the protective relay device of the seventh embodiment, compared with the protective relay device of the first to fifth embodiments, the stop control of the generator 15 after the power transmission line 3 is in a non-powered state is more performed. The effect that it can be performed rapidly is acquired.

  In the present embodiment, the connection breaker 14 is shut off when the operation of the generator 15 is quickly stopped, but the present invention is not limited to this control. For example, a control signal may be output to another control device (not shown) that can quickly stop the operation of the generator 15, and the same effect as in the present embodiment can be obtained.

Embodiment 8 FIG.
FIG. 10 is a partial configuration diagram of an electric power system including an electrical facility to which the protective relay device according to the eighth embodiment of the present invention is applied, and is different from FIG. 5 in the overall configuration diagram shown in FIG. The part of the electrical equipment 6 which is a point is shown. Here, the difference from FIG. 5 is that the number of generators connected via the connection breaker is plural. Specifically, a generator 24 connected via the connection point breaker 23 and a generator 26 connected via the connection point breaker 25 are additionally connected. The eighth embodiment assumes that the total rated power by the generators 15, 24, and 26 is larger than the load capacity of the load 17.

  Next, the operation of the protective relay device according to the eighth embodiment will be described. The movement until the connection point breaker 8 is cut off is the same as in the first and fourth embodiments and the description thereof is omitted. When the connection point break signal 13 is output and the connection point breaker 8 is cut off, the electrical equipment 6 is disconnected from the power transmission line 3 (see FIG. 5 and the like) of the power system. The generators 15, 24, and 26 supply power to the load 17 in the electrical facility 6.

  Here, when a plurality of generators are connected as shown in FIG. 10, as the generator cutoff control, for example, the junction breakers 14, 23, and 25 are sequentially shut off. When such control is performed, the overvoltage is eliminated during the interruption control. As a result, when the overvoltage relay 20 is restored, the subsequent interruption is not performed. With this control, the generator is in a state in which continuous operation is possible, and thereafter, the generator is not shut off or stopped by other control, and the load 17 in the electrical equipment 6 is continuously operated safely. .

  In the present embodiment, when one or more of the generators 15, 24, and 26 are quickly stopped, one or more of the connection breakers 14, 23, and 25 are sequentially disconnected. However, the present invention is not limited to this control. For example, a control signal may be output to another control device (not shown) that can quickly stop the operation of the generators 15, 24, and 26, and the same effect as the present embodiment can be obtained. .

Embodiment 9 FIG.
FIG. 11 is a partial configuration diagram of an electric power system including an electrical facility to which the protective relay device according to the ninth embodiment of the present invention is applied. Of the entire configuration diagram shown in FIG. The part of the electrical equipment 6 which is a point is shown. Here, the difference from FIG. 5 is that the number of loads connected via the load circuit breaker is plural. Specifically, a load 30 connected via the load circuit breaker 28 is additionally connected. The ninth embodiment assumes a case where the rated power by the generator 15 is smaller than the load capacity of the loads 17, 30, and 31.

  Next, the operation of the protective relay device according to the ninth embodiment will be described. The movement until the connection point breaker 8 is cut off is the same as in the first and fourth embodiments and the description thereof is omitted. When the connection point break signal 13 is output and the connection point breaker 8 is cut off, the electrical equipment 6 is disconnected from the power transmission line 3 (see FIG. 5 and the like) of the power system. The generator 15 supplies power to the loads 17, 30, and 31 in the electrical facility 6.

  Here, when a plurality of loads are connected as shown in FIG. 11, as the load breaking control, for example, the load breakers 27, 28, and 29 are sequentially cut off in this order. When such control is performed, the undervoltage is eliminated during the interruption control. As a result, when the undervoltage relay 11 is restored, the subsequent interruption is not performed. With this control, the generator is in a state where continuous operation is possible, and thereafter, the load is not interrupted by other control, and the constant load in the electrical equipment 6 is safely operated continuously.

  In the present embodiment, one or more of the load circuit breakers 27, 28, and 29 are sequentially disconnected when one or more of the loads 17, 30, and 31 are quickly stopped. It is not limited to control. For example, a control signal may be output to another control device (not shown) that can quickly stop the load circuit breakers 27, 28, and 29, and the same effect as the present embodiment can be obtained.

  In the first to ninth embodiments, the undervoltage detection function at the connection point with the power system, the overvoltage detection function at the connection point, and the voltage frequency ratio detection function at the connection point are provided as undervoltage. Although the embodiment in which the relay 11, the overvoltage relay 20, and the V / F relay 12 are assigned to have been described, the undervoltage detection unit having the function of detecting the undervoltage at the connection point without using each of these relays, the connection point An overvoltage detection unit having an overvoltage detection function and a voltage frequency ratio (V / F) detection unit having a function of detecting a voltage frequency ratio (V / F) at a connection point are appropriately selected according to each embodiment. You may be the structure to provide.

  As described above, the protective relay device according to the present invention is useful as an invention that enables early disconnection of electrical equipment and quick restoration of a power system without complicating the configuration of the device.

1,5 Substation 2,4 Circuit breaker 3 Transmission line 6,7 Electrical equipment 8 Interconnection point circuit breaker (first circuit breaker)
9 Receiving point bus 10 Instrument transformer 11 Undervoltage relay 12 V / F relay 13 Interconnection point breaking signal 14, 23, 25 Junction breaker (second breaker)
DESCRIPTION OF SYMBOLS 15, 24, 26 Generator 16 Transformer 17 in electrical installation 17, 18, 30, 31 Load 19 AND circuit with negative terminal 20 Overvoltage relay 21 Generator cutoff signal 22 AND circuit 27, 28, 29 Load circuit breaker

Claims (12)

In a protective relay device connected to an electric power system and applied to electrical equipment including at least one generator,
In the electrical equipment, an undervoltage detection unit that detects a voltage drop at a connection point with the power system, a V / F detection unit that detects a voltage frequency ratio (V / F) at the connection point, Is provided,
When the undervoltage detection unit detects a voltage drop at the connection point and the voltage frequency ratio detected by the V / F detection unit is normal, the connection between the power system and the electrical equipment is established. A protective relay device characterized by being cut off.   The part of the phase in which the undervoltage detection unit detects an undervoltage and the part of the phase in which the V / F detection unit detects a voltage frequency ratio are different. Protective relay device.   When the state in which the undervoltage detection unit detects a voltage drop at the interconnection point and the state in which the voltage frequency ratio detected by the V / F detection unit is normal continue the generator The protective relay device according to claim 1, wherein the protective relay device is disconnected from the electrical equipment.   After the connection between the power system and the electrical equipment is cut off, a voltage drop at the connection point is detected by the undervoltage detection unit, and a normal voltage frequency ratio is detected by the V / F detection unit 3. The protective relay device according to claim 1, wherein the generator is disconnected from the electrical equipment when the operation is performed. 4. When a plurality of loads are connected in the electrical equipment,
The protective relay device according to any one of claims 1 to 4, wherein the load is sequentially cut off, and the cut-off control for the load is stopped when an insufficient voltage at the interconnection point is resolved. The electrical equipment is connected to the power system via a first circuit breaker, and the generator is connected to a bus in the electrical equipment via a second circuit breaker,
An undervoltage relay and a V / F relay are provided in the electrical equipment, and the function of the undervoltage detector is implemented by the undervoltage relay, and the function of the V / F detector is the V / F relay. When the configuration embodied by
When the first circuit breaker is operated and the interconnection between the power system and the electrical equipment is cut off, the undervoltage relay detects a voltage drop at the interconnection point, and the V / F 6. The protective relay device according to claim 5, wherein when the voltage frequency ratio detected by the relay is normal, the second circuit breaker is controlled to disconnect the generator from the electrical equipment. . In a protective relay device connected to an electric power system and applied to electrical equipment including at least one generator,
In the electrical equipment, an overvoltage detection unit that detects an overvoltage at a connection point with the power system, and a voltage frequency ratio detection unit that detects a voltage frequency ratio at the connection point are provided,
When the overvoltage detection unit detects an overvoltage at the connection point and the voltage frequency ratio detected by the V / F detection unit is normal, the connection between the power system and the electrical equipment is cut off. A protective relay device characterized by that.   The protection according to claim 6, wherein a part of the phase in which the overvoltage detection unit detects an overvoltage is different from a part of the phase in which the V / F detection unit detects a voltage frequency ratio. Relay device.   When the state in which the overvoltage detection unit detects an overvoltage at the interconnection point and the state in which the voltage frequency ratio detected by the V / F detection unit is normal continue the electric equipment The protective relay device according to claim 6 or 7, wherein the protective relay device is disconnected.   After the connection between the electric power system and the electrical equipment is cut off, an overvoltage at the connection point is detected by the overvoltage detection unit, and a normal voltage frequency ratio is detected by the V / F detection unit. 8. The protective relay device according to claim 6, wherein the generator is disconnected from the electrical equipment. When a plurality of generators are connected in the electrical equipment,
10. The protective relay device according to claim 6, wherein when the generator is sequentially shut down and the overvoltage at the interconnection point is resolved, the shut-off control for the generator is stopped. The electrical equipment is connected to the power system via a first circuit breaker, and the generator is connected to a bus in the electrical equipment via a second circuit breaker,
In the electrical equipment, an overvoltage relay and a V / F relay are provided, the function of the overvoltage detection unit is implemented by the overvoltage relay, and the function of the V / F detection unit is implemented by the V / F relay. When the configuration is
When the first circuit breaker is operated and the interconnection between the power system and the electrical equipment is cut off, the overvoltage relay detects an overvoltage at the connection point, and the V / F relay is The protective relay device according to claim 11, wherein when the detected voltage frequency ratio is normal, the second circuit breaker is controlled to disconnect the generator from the electrical equipment.

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