JP4068624B2 - Electrostatic high voltage synchronous phase detection method and apparatus - Google Patents

Description

  The present invention relates to an electrostatic high-voltage synchronous phase detection method according to a power generation facility used in a utility power plant, a mobile power generation facility, and the like, and an electrostatic high-voltage synchronous phase detection device used directly for the implementation.

  Currently, when operating generators in grid-connected utility power stations and mobile power generation facilities, it is common practice to use multiple small-capacity high-voltage generators to increase efficiency at low loads. is there.

  As a specific operation method, a method in which individual generators are arranged in parallel to the bus is used, and this parallel operation is performed by automatically starting a stopped generator in accordance with an increase in load, and providing synchronization with each generator. The device (automatic parallel device) is set to automatically parallel when the three elements of voltage, frequency and phase difference fall within the specified conditions. Then, as the above value decreases, the line is disconnected and the system waits for the next activation.

  In the conventional power generation facility, as shown in FIG. 8, a plurality of generators G ′ (1, 2,... N) are individually dispersed in a package shape, and three copper bars γ corresponding to a three-phase bus Ln. (1, 2... N) arranged in an orderly manner was used, but now, as shown in the parallel connection wiring diagram of FIG. A method is used in which three high-voltage cables of the core are sequentially connected in parallel with a triplex twisted together. In the figure, Ld indicates a load, and W indicates a power meter.

The method for confirming the synchronization timing and voltage will be described with reference to FIG. 9A. The generator G ′ is provided with a composite instrument synchronizer D and an instrument transformer Vt for detecting the bus voltage. On the secondary side of the instrument transformer (P ₁ , P ₂ , P _{3 in the} figure), a voltmeter, a wattmeter, a protection device, etc. (not shown) that require voltage elements are sequentially connected in parallel.

Also, academically, phase rotation is turned to the left or right in the order of RST or UVW with reference to the R phase, so that RST (UVW) is the secondary of the instrument transformer Vt as shown in FIG. 9B. corresponds to the side _{P 1,} P 2, _{P 3,} by measuring the values of _{P 1,} P 2, _{P 3} of the bus side, has been performed to confirm the synchronization.

  FIG. 10 is a layout diagram of a conventional power generation facility combined with the above system. The power generation facility β ′ includes a generator G ′, a parallel breaker δ ′, a generator high-voltage line 17, a generator output cable 11 ′, and a bus. The cable 12 'and the instrument transformer Vt are provided, and the high voltage output from the generator G' flows through the generator high voltage line 17 to the parallel breaker δ ', the generator output cable 11', and the bus cable 12 '. The synchronization time was confirmed through a series of means of measuring the voltage transformed through the instrument transformer Vt.

  Here, as a problem that occurs in the test process until the completion of the grid-connected utility power station or mobile power generation equipment using the power generation equipment described above, the synchronization device is connected in parallel after the single unit test run is completed. If it does, the phase rotation will be reversed and a synchronization failure will occur, and the power generation equipment may cause an instantaneous short circuit.

  When an instantaneous short-circuit is caused, for example, a shear pin (a device that disconnects when an abnormal load is applied) in a gas turbine engine or a crankshaft in a diesel engine breaks. In the case of breakage, there is a risk of causing personal injury of workers involved in the inspection and adjustment of the device due to excessive connecting rods breaking through the oil pan and popping out.

  In addition, because it was disconnected by an electrical protection device, even if it did not cause a failure in appearance, it could not be predicted that a problem remained in the mechanically vulnerable part, and the remaining problem could not be solved in the future. There are also issues related to quality assurance and maintenance that can cause serious failures.

  The synchronization failure that causes this momentary short circuit occurs most often before the parallel breaker is disconnected, and is most often caused by the phase rotation being reversed at the connection between the bus and the generator and the high-voltage cable.

  First, the cause of synchronization failure is a high-voltage cable identification error. In general, colors are assigned to RST or UVW wiring cables of each power source and recognized.

  For example, generator manufacturers and high voltage wiring operators customarily use RST (UVW) arrangements of red, white, blue or black, respectively. However, as shown in Table 1 below, electric utilities and telecommunications companies traditionally use their own identification display, and sometimes there is an error in the recognition of the identification display on both ends of the high-voltage cable between the two. And cause the phase rotation to be reversed.

Further, on the secondary side (P ₁ , P ₂ , P ₃ ) of the instrument transformer Vt described in FIG. 9B, the reverse of the phase rotation is reversed until P ₁ and P ₂ reach the synchronizer D. May cause.

  In a synchronous device in recent years, as described above, even if a connection difference occurs between the high voltage side (shown by dotted line V′1 in FIG. 9) and the low voltage side (shown by dotted line V′2 in FIG. 9), If the voltage, frequency, and phase difference, which are the three phases of the single-phase instrument transformer Vt at both ends of the circuit breaker δ ′, coincide with each other, even if the phase rotation is reversed, as shown in FIG. Since it is possible to generate a parallel signal even at about 180 °, synchronization failure occurs due to a difference in connection.

  However, there are cases where input errors in the combined instrument and sequencer cannot be avoided even with careful pre-inspection.

  Therefore, as the most accurate method for preventing synchronization failure, the investigator starts up the bus Ln and the generator G ′ at the installation site, and uses the bus Ln of the parallel breaker δ ′ and the high-pressure three-phases at both ends of the generator G ′. A method of actual measurement is used.

  At present, a high-voltage detector phase detector that can detect the phase rotation and synchronization timing at both ends of the parallel breaker δ 'at the same time is an undeveloped field, so a voltage detector phase detector for high-voltage overhead lines and underground lines is used. ing

  FIG. 12 shows an example of the voltage detection phase detector A (1, 2, 3), and its structure and shape are various as shown in (a) to (c). Contact portions A11, A21, A31 are present at the tip of the container A, and the voltage is inspected by directly contacting the contact portions A11, A21, A31 with the terminals.

  In this case, the voltage detector / phase detector A has a constant frequency electrically, and the detection part is structurally a hanging type or a contact type, so that the investigator does not touch the track (c) It is made as long as possible using A32 or the like.

  However, in the detection of the phase rotation and the synchronization timing, as shown in the layout diagram of the power generation equipment in FIG. 10, high voltage wiring such as an instrument transformer Vt is intertwined around the parallel circuit breaker δ ′, and each component Is fixed with bolts, but is fixed with vinyl tape to connect the tip of voltage detector phase detector A for high-voltage lines without fixing method to the terminal of parallel breaker δ ', and the barrel to other parts Detection is performed while being tied and fixed with an insulating string or the like.

  This method causes unstable conduction due to unstable fixation, and attention is paid to reworking. Despite wearing insulating gloves, the body accidentally touches other high-voltage lines, resulting in an electric shock. There is a fear of triggering.

  In addition, in the synchronization failure described in the above example, the investigator's mistake is first suspected as the cause, so that the cause elucidation is delayed.

  In addition, once a synchronous link is established in a permanent power plant, the coordinator will not be exposed to high pressure. However, if a power plant is expanded or the factory is upgraded, the same risk will arise in the subsequent parallel adjustment. In addition, in the mobile power generation device, it is necessary to perform parallel adjustment at the destination of the movement, and therefore the risk frequency is further increased.

  Here, the main objects to be solved by the present invention are as follows.

  That is, the first object of the present invention is to detect the phase rotation of the high-voltage circuit and the appropriate synchronization timing without the investigators approaching the high-voltage terminals at both ends of the parallel breaker, and the parallel signal generated by the synchronizer is appropriate. It is intended to provide a synchronous phase detection method and apparatus for determining whether or not.

  The second object of the present invention is to provide a synchronous phase detection method and apparatus that enables easy confirmation of the synchronization timing and measurement of high-pressure three-phase without installing new large-scale equipment. is there.

  The third object of the present invention is to provide a synchronous phase detection method and apparatus only with a switch operation that does not use a voltage detection phase detector having an unstable operation at work.

  Other objects of the present invention will become apparent from the specification, drawings, and particularly the description of each claim.

  In the device of the present invention, high voltage is converted into low voltage minute current to electrostatic synchronous phase detection device α in a normal or mobile power generation facility, and the combined current on the generator side and bus side of the converted low voltage minute current is An electrostatic type instrument transformer to be calculated, a bus side, a generator side, a main changeover switch circuit for switching the combined current, and an N / R switch circuit for self-diagnosis of the phase rotation synchronization state are combined. An ammeter group A that displays the value of the current conducted by the main changeover switch circuit that switches the switching information downward among the low voltage board circuit and the four patterns of the generator side, bus side, synchronous state, and off state. And a means for providing means.

  Further, in the method of the present invention, an electrostatic instrument transformer is arranged on each of the three phases on the bus side and the generator side of the connected parallel circuit breaker connected to the generator in the power generation facility, and high voltage is applied. By measuring the total current of the three phases converted into the low-voltage current with an ammeter, the method has a feature that it is possible to check the three-phase rotation and the synchronization timing.

  More specifically, in order to solve the problem, the present invention achieves the above-mentioned object by adopting a novel characteristic configuration method or means ranging from the superordinate concept listed below to the subordinate concept. Is done.

  That is, the first feature of the device of the present invention is that in a power generation facility such as a grid-connected utility power plant or a mobile power generator, a static connection for confirming a phase rotation of a plurality of high-voltage generators connected in parallel and an appropriate synchronization timing is provided. This is an electric high-voltage synchronous phase detector, and the high voltage of each three-phase RST (UVW) output through the generator on the generator side on both sides sandwiching the connected parallel circuit breaker and the busbar side, respectively. Transform to a low-voltage micro-current, and calculate each combined current of the low-voltage micro-current on the generator side and bus side, and each low-voltage micro-current on the generator side and bus side, and A low-voltage board circuit that switches the value of each of the three phases of the combined current of the low-voltage microcurrent, and an ammeter group that visually displays the value of the combined current switched by the low-voltage board circuit, The low-voltage board circuit is connected to the generator side and bus side of each of the three phases. Normal by switching the N and R contacts based on the main changeover switch circuit that switches the low-voltage microcurrent and the value of the combined current, and the value indicated by the other phase based on the maximum value of each phase ON / OFF switching information on the generator side, bus side, synchronized state, and off state in the low-voltage panel circuit. The main changeover switch circuit is configured to be freely switchable in accordance with the configuration of an electrostatic high voltage synchronous phase detector.

  A second feature of the method of the present invention is that the electrostatic instrument transformer according to the first feature of the device of the present invention is an electrostatic insulator and constitutes a zero-phase voltage detection capacitor. The configuration of the electric high-voltage synchronous phase detector is adopted.

  The third feature of the device according to the present invention is that the electrostatic insulator in the first feature of the device according to the present invention has an outer diameter, except that the number of ridges and valleys in the middle outer periphery is larger than that of a general-purpose insulator generally used. The configuration of the electrostatic high-voltage synchronous phase detector is an indoor insulator having almost the same length.

  A fourth feature of the device of the present invention is that the main changeover switch circuit according to the first or second feature of the device of the present invention described above is switching information of four patterns of the generator side, the busbar side, the synchronized state, and the off state. Therefore, the electrostatic high-voltage synchronous phase detection device is employed as an interlocking switch that transmits the value of the low-voltage microcurrent that has been conducted in response to the current meter group to measure and display the value.

  A fifth feature of the device of the present invention is that the main changeover switch circuit according to the first, second, third or fourth feature of the device of the present invention is formed by a small relay or a cam switch. It is in the configuration adoption of the synchronous phase detector.

  The sixth feature of the device of the present invention is the fear of electric shock that can be easily monitored when the ammeter group in the first, second or third feature of the present invention device is installed near the parallel breaker. The configuration of the electrostatic high-voltage synchronous phase detector is installed at a position where there is no gap.

  That is, the first feature of the method of the present invention is that in a power generation facility such as a grid-connected utility power plant or a mobile power generator, a static connection for confirming a phase rotation of a plurality of high-voltage generators connected in parallel and an appropriate synchronization timing is provided. Electrostatic high-voltage synchronous phase detection method, comprising electrostatic transformers for each of the three phases of the high-voltage terminal RST (UVW) on the high-voltage generator side and the bus-bar side on both sides sandwiching the parallel circuit breaker The high voltage of the generator is converted into a low-voltage microcurrent, and the calculated current is calculated as a combined current using a main changeover switch circuit in the low-voltage board circuit, and the generator side and the bus side respectively. Switching between the low-voltage microcurrent and the calculated combined current, and when the combined current reaches the maximum value is set as a healthy synchronous start-up time of the parallel breaker, the three phases of the high-voltage generator are in phase Determine whether the rotation status is normal or abnormal Comprising Confirm the synchronization state of the power plant by, in the configuration adopting the electrostatic high-voltage synchronization Kensho method.

  A second feature of the device of the present invention is that when the combined current of the low-voltage microcurrent in the first feature of the method of the present invention is measured with each phase ammeter within about 1 mA, and the phase rotation is in a normal state, The configuration of the electrostatic high-voltage synchronous phase detection method, in which when the three phases coincide and amplitude, and the phase rotation is abnormal, the three phases are offset by 120 ° and the phase rotation is confirmed. Adopted.

  According to a third feature of the method of the present invention, in the first or second feature of the method of the present invention, the main changeover switch circuit is configured to reduce the low-voltage microcurrent on the generator side and the busbar side, and the combined current. In order to prevent the induction of high-voltage current directly connected to the displayed ammeter group, the configuration of the electrostatic high-voltage synchronous phase detection method, in which two of the four contacts of the main changeover switch circuit are normally closed, is adopted. is there.

  A fourth feature of the method of the present invention is that the ammeter group according to the first, second or third feature of the method of the present invention is configured such that all the contact groups of the main changeover switch circuit are in an ON state, When the parallel breaker is turned on after establishing the voltage of the generator before connection of the three, if normal, the three-phase shows the highest value of the sum of the low-voltage microcurrents on the generator side and the bus side The configuration of the electrostatic high-voltage synchronous phase detection method.

  A fifth feature of the method of the present invention is that the electrostatic instrument transformer according to the first, second, third, or fourth feature of the method of the present invention includes an electrostatic insulator that forms a zero-phase voltage detection capacitor. When using, it replaces the existing support insulator installed around the parallel breaker, or adopts the configuration of the electrostatic high-voltage synchronous phase detection method that is additionally used.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to determine the appropriateness | suitability of the parallel signal of a safe synchronizer, without an operator being exposed to a dangerous material in the case of parallel adjustment of power generation equipment.

  In addition, by using a low-voltage microcurrent as a measurement value, an accurate numerical value can be derived, and it is possible to easily check the synchronous on-off region of the parallel breaker and its timing. It is possible to ensure stable and safe driving.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings and examples of the apparatus and corresponding methods.

(Example of equipment)
First, an outline of this apparatus example will be described with reference to FIG. FIG. 1 is a configuration diagram showing an arrangement configuration in a power generation facility β according to the present invention.

  As shown in the figure, the power generation facility β includes a generator G, a parallel breaker δ, and an electrostatic high-voltage synchronous phase detector α, and the generator high-voltage line 17 generates power via the parallel breaker δ. It is divided into the machine output cable 11 and the bus cable 12 and enters the electrostatic high voltage synchronous phase detector α, and the high voltage is converted into a low voltage micro current by the electrostatic insulator 13a, which is the sum of the currents on the generator side and the bus side. After the combined current is calculated, the value is visually displayed on the ammeters AR, AS, and AT groups mounted on the panel 16.

  The electrostatic high-voltage synchronous phase detector α includes an electrostatic insulator 13a and a low-voltage board circuit 14. FIGS. 2 (a1) and 2 (a2) are a front view and a side view of the electrostatic insulator 13a used in the present invention. It is a block diagram, (b1), (b2) is the front view and side block diagram of the general purpose insulator 13b generally used. (A), (b) As shown in both drawings, the outer diameter and length of the electrostatic insulator 13a used in the present invention and the outer diameter and length of the general-purpose insulator 13b are substantially the same. Therefore, it is not necessary to provide a new installation place for the electrostatic insulator 13a in the parallel breaker δ, and the general-purpose insulator 13b and the electrostatic insulator 13a that are installed regularly around the parallel breaker δ can be easily replaced. It is possible. The difference between the electrostatic insulator 13a and the general-purpose insulator 13b is that the number of ridges and valleys on the intermediate outer periphery is large, and the distance between the bolt holes provided in a pair on the tip surface is slightly increased to improve the transformation function characteristics.

  In addition, compared with the generally used instrument transformer Vt, the electrostatic insulator 13a is small and light and relatively inexpensive. Therefore, the electrostatic insulator 13a is arranged not only for replacement but also for additional installation. There is no problem in space.

  Next, the low voltage board circuit 14 is a circuit for displaying the low voltage minute current converted from the high voltage by the electrostatic insulator 13a on the ammeters AR, AS, AT of the panel 16 as a voltmeter. It includes a main changeover switch circuit 15a for switching not only current but also voltage values of the bus cable 12 and the generator G, respectively. In this case, a small relay, a cam switch or the like may be used as the contact of the main changeover switch circuit 15a.

  FIG. 3 shows an example of a panel 16 for an investigator to visually confirm the three-phase synchronization timing. The panel 16 includes a main switching rotary switch 15b and a low-pressure micro switch corresponding to each phase. Ammeters AR, AS, and AT are mounted. In the figure, 18 is an N / R snap switch, and 19 and 20 are a generator side connection terminal group and a bus side connection terminal group, respectively.

  The panel 16 is installed near the parallel breaker δ. The installation position of the panel 16 in FIG. 1 is an example, and the installation position is not specified and can be easily monitored by an investigator. If it is installed in a position where there is no fear of electric shock, it can be said that the safety at the time of inspection increases. .

  The main switching rotary switch 15b has four patterns of bus, generator, synchronous, and off. When the rotary switch 15b is rotated and switched, the current value on the bus side, the current value on the generator side, and the low-voltage minute current between the bus and the generator are combined. Switching information is transmitted to the ammeters AR, AS, and AT groups so as to display the current value.

  The ammeters AR, AS, AT are transmitted to the main changeover switch circuit 15a by the turning operation of the main changeover rotary switch 15b, and visually indicate the current values of the three phases of the power supplies R, S, T introduced from the main changeover switch 15a. In the state where the synchronous N / R snap switch 18 is selected to close the N contact, it is determined that the parallel breaker δ should be closed as the synchronous closing region B when all the values become the maximum value. .

(Example method)
Next, an embodiment according to the method of the present invention to which the above apparatus example is applied will be described with reference to FIGS.

  FIG. 4 is an electric circuit diagram of the electrostatic high-voltage phase detector α and the parallel breaker δ, (a) is a wiring diagram showing details of the connection contents, and (b) is an R phase and a U phase. It is a circuit diagram about only the case. As shown in FIG. 4A, an electrostatic insulator 13 is connected to each phase of the bus-side power sources R, S, T and the generator-side power sources U, V, W of the parallel breaker β, Each is connected to a low voltage board circuit 14.

  In FIG. 4A, the extracted R phase and U phase portions are shown in FIG. 4B. In this case, when the electrostatic capacity of the electrostatic insulator 13 is 250 PF in the R phase, the operating voltage is 6600 V and 50 Hz or less. When the calculation is applied to Equation 1 below, a ground current of about 0.3 mA is derived and can be measured with an ammeter AR of about 1 mA.

上記数式１において、Ｉ_ＣＯは対地電流値を示し、Ｉ_ＣＯは電圧Ｅと、周波数ｆによって導き出される。

In Equation 1 above, I _CO represents a ground current value, and I _CO is derived from the voltage E and the frequency f.

  Based on the numerical value derived from Equation 1, when the bus cable 12 and the generator G are connected in parallel at the same voltage and the same phase (0 degree position), 0.6 mA is the maximum value and 0 mA is the minimum value from Equation 2 below. As derived. The state of this maximum value is the synchronization input area B that is the timing of synchronization.

このとき、Ｉ_ＲはＲ相における低圧微小電流の値を表す。Ｉ_ＣＲは母線側の低圧微小電流の値、Ｉ_ＣＵは発電機側の低圧微小電流の値をそれぞれ指し示し、母線側と発電機側の低圧微小電流の合計電流の和が最大値、つまり位相差φ＝０゜のとき、同期投入領域Ｂとなり、位相差φ＝１８０゜のときは最小値０が導き出される。

In this case, I _R represents the value of the low-pressure micro-current in the R phase. I _CR is the value of the low small current of the bus side, I _CU points to the value of the low small current on the generator side, respectively, bus side and sum maximum of the total current of low voltage small current on the generator side, i.e. the phase difference When φ = 0 °, the synchronous input region B is obtained. When the phase difference φ = 180 °, the minimum value 0 is derived.

  FIG. 5 is a waveform diagram of the phase rotation applied to the S phase and the T phase in the same manner as the R phase as in the R phase. FIG. 5A is a normal phase state, and FIG. 5B is a reverse phase (reverse phase rotation). ) State and (c) are waveform diagrams of beat voltages when a conventional instrument transformer is used.

  When the phase rotation is in the normal phase state, 0.6 mA is calculated to be the maximum value when the phase difference φ is 0 ° from the above formulas 1 and 2, and the synchronous input region B is set when the phase difference is the maximum value. Along with the phase shift, the current decreases, and shows a minimum value of 0 mA when the phase difference φ is 180 °.

  In the state of FIG. 5A, when the phase rotations coincide (in the normal phase state), the three-phase ammeters AR, AS, AT show approximately the same value, and perform amplitude according to the difference in frequency. As the frequency of the phase approaches, the maximum value persists, and the synchronous input region B becomes apparent. When the phase rotation is reversed (anti-phase state), the three phases shift in amplitude by about 120 ° and perform amplitude.

  In the conventional method using an instrument transformer, the synchronous input region B is set when the voltage indicates the minimum value (zero beat), but it is difficult to confirm the minimum voltage value at the high voltage. On the other hand, in the present invention, since the range of the current value is within 1 mA, the point that the maximum value can be easily confirmed is also effective.

  By connecting the wiring based on the above principle, the low-voltage minute current converted from the high voltage of the bus cable 12 and the generator G is rotated and switched by the main changeover switch circuit 15a and the main changeover rotary switch 15b. It is possible to measure with a total of AR, AS, and AT.

  The N / R switch circuit in the low voltage board circuit 14 establishes the voltage of the generator G before connecting to the bus cable 12 and then turns on the parallel breaker δ. Both show the maximum value in the synchronous input region (on the approximately 0 ° line).

  When the N / R switch circuit 21 is switched to the R (reverse) side, the R phase shows the highest value in the healthy synchronous input region (on the approximately 0 ° line), and the other S and T phases have significantly different values ( Each phase difference of 120 ° is indicated, and can be used as a criterion.

上記表において、１はＯＮ、０はＯＦＦ状態を示す。 FIG. 6 shows an example of use when a small relay is used for the main changeover switch circuit 15a. As shown in Table 2 below, the main changeover rotary switch 15b is set to one of bus, generator, synchronous, and off. Check phase rotation and synchronization timing.

In the above table, 1 indicates ON and 0 indicates OFF state.

  FIG. 7 shows an example in which a cam switch is used for the main changeover switch circuit 15a. 1 is a busbar, 2 is a generator, 3 is off, 4 is a synchronous state, and the small relay is shown. As in the case of using it, it is possible to confirm whether the phase rotation and synchronization timing are normal by setting the main switching rotary switch 15b to each part.

In this case, Y _P of the main change-over switch circuit _15a, the contacts _{of the} Y G causes the closing always performed to prevent high pressure dielectric.

  The above is an example of the apparatus according to the present invention and the embodiment according to the method of the present invention. However, the present invention is not necessarily limited to the above-described means and methods, and may be appropriately selected within the scope of the above-described effects. It is possible to implement changes.

It is a schematic diagram of the electric power generation equipment carrying the electrostatic type high voltage | pressure synchronous phase detection apparatus which concerns on the example of an apparatus of this invention. It is explanatory drawing which shows the electrostatic insulator which concerns on the example of an apparatus of this invention, (a1), (a2) is each a front view and side view of the electrostatic insulator used for this invention, (b1), (b2) These are a front view and a side view, respectively, of a generally used insulator. It is explanatory drawing of the example of mounting arrangement on the panel which concerns on the apparatus example of this invention. It is explanatory drawing of the electrostatic high voltage | pressure synchronization method which concerns on the embodiment of this invention, (a) is a circuit diagram, (b) is the circuit diagram which extracted only the part which concerns on R phase and U phase. It is explanatory drawing of the phase rotation of the three-phase which concerns on the example of embodiment of this invention method, (a) is a waveform diagram at the time of coincidence of phase rotation (normal phase), (b) is at the time of reverse (antiphase) of phase rotation (C) is a waveform diagram of a beat voltage used in a conventional instrument transformer. It is circuit explanatory drawing at the time of using a small relay for the main changeover switch circuit concerning the example of an embodiment of the present invention. It is circuit explanatory drawing at the time of using a cam switch for the main changeover switch circuit concerning the example of an embodiment of the present invention. It is arrangement | positioning block diagram of the parallel connection apparatus in the conventional power generation equipment. It is a block diagram of the parallel connection of the generator in the conventional power generation equipment. It is explanatory drawing of the synchronizer using the instrument transformer in the conventional power generation equipment, (a) is a circuit diagram of parallel connection, (b) is explanatory drawing of the phase rotation direction of a bus-line and a generator. It is explanatory drawing of the synchronizer in the conventional power generation equipment, (a) is explanatory drawing of the normal connection at the time of normal connection, (b) is explanatory drawing of the anti-connection at the time of abnormal connection. (A), (b), (c) is explanatory drawing of the various voltage detectors in the conventional power generation equipment, and is a block diagram of the high voltage voltage detection rod for high voltage overhead lines or underground lines.

Explanation of symbols

α ... electrostatic high-voltage synchronous phase detector β, β '... power generation equipment G, G' ... generators γ1, γ2, γn ... copper bars δ, δ '... parallel breakers A1, A2, A3 ... high-voltage detection rod A11 , A21, A31 ... contact part A32 ... relay rod AR, AS, AT ... low-voltage microammeter Vt ... instrument transformer D ... compound instrument synchronizer Ln ... bus Ld ... load W ... wattmeter 11 ... generator output cable 12 ... bus bar cable 13a ... electrostatic insulator 14 ... low voltage board circuit 15a ... main changeover switch circuit 15b ... main changeover rotary switch 16 ... panel 17 ... generator high voltage line 18 ... N / R snap switch 19 ... generator side connection terminal group 20 ... Bus side connection terminal group 21 ... N / R switch circuit

Claims (11)

In a power generation facility such as a grid-connected utility power plant or a mobile power generator, an electrostatic high-voltage synchronous phase detector that performs phase rotation of a parallel connection of a plurality of high-voltage generators and confirmation of an appropriate synchronization timing,
The high voltage of each three-phase RST (UVW) output through the generator on both the generator side and the busbar side with the parallel parallel breaker in between is converted into a low-voltage microcurrent, and the generator side , An electrostatic instrument transformer for calculating each combined current of the low-voltage microcurrent on the bus side,
A low-voltage board circuit for switching the values of the three phases of the low-voltage microcurrent on the generator side and the bus-bar side and the combined current of the low-voltage microcurrent;
An ammeter group for visually displaying the value of the combined current switched by the low-voltage board circuit;
The low-voltage board circuit is a main changeover switch circuit for switching the value of the low-voltage microcurrent on the generator side of each of the three phases, the bus-side, and the combined current;
N / R switch for self-determination of whether or not phase rotation is normally performed by switching the N and R contacts based on the value indicated by the other phase based on the maximum value of each phase A circuit,
The main changeover switch circuit is configured to be freely switchable according to ON / OFF switching information of the generator side, bus side, synchronous state, and off state in the low-voltage board circuit.
An electrostatic high-voltage synchronous phase detector. The electrostatic instrument transformer is:
An electrostatic insulator that constitutes a zero-phase voltage detection capacitor;
The electrostatic high-voltage synchronous phase detector according to claim 1. The electrostatic insulator is
It is an indoor insulator that has almost the same outer diameter and length, except that there are a large number of steps in the middle and outer circumference than the general-purpose insulator that is generally used.
The electrostatic high-voltage synchronous phase detection device according to claim 1, wherein: The main selector switch circuit is
An interlocking switch that transmits to the ammeter group that measures and displays the value of the low-voltage microcurrent that is conducted according to the switching information of the four patterns of the generator side, the bus side, the synchronous state, and the off state,
The electrostatic high-voltage synchronous phase detector according to claim 1 or 2. The main selector switch circuit is
Formed with small relays or cam switches,
5. The electrostatic high-voltage synchronous phase detection device according to claim 1, 2, 3 or 4. The ammeter group is:
When installing in the vicinity of the parallel breaker, install in a position where there is no fear of electric shock that can be easily monitored,
The electrostatic high-voltage synchronous phase detector according to claim 1, 2, or 3. An electrostatic type high-voltage synchronous phase detection method for confirming appropriate synchronous timing and phase rotation of parallel connection of a plurality of high-voltage generators in a power generation facility such as a grid-connected utility power plant or a mobile power generator,
An electrostatic instrument transformer is connected to each of the three phases of the high-voltage terminal RST (UVW) on each of the high-voltage generator side and the bus-bar side on both sides of the parallel circuit breaker, and each high voltage of the generator is What is converted into a low-voltage minute current and calculated as a combined current is
Using the main changeover switch circuit in the low voltage board circuit, switching the low voltage minute current on each of the generator side and the bus side and the calculated composite current,
On the basis of the time when the combined current becomes the maximum value as a time for a healthy synchronous closing of the parallel breaker,
Confirming the synchronized state of the power generation equipment by judging whether the phase of the three phases of the high-voltage generator is normal or abnormal,
An electrostatic high-voltage synchronous phase detection method characterized by the above. The combined current of the low-voltage microcurrent is
Measured with each phase ammeter within about 1 mA, and when the phase rotation is in a normal state, the three phases coincide and amplify,
When the phase rotation is in an abnormal state, the three phases are offset by 120 ° and the amplitude is checked.
The electrostatic high-voltage synchronous phase detection method according to claim 7. The main selector switch circuit is
Directly connected to the low-voltage microcurrent on the generator side and the busbar side, and an ammeter group that displays the combined current,
In order to prevent induction of high voltage current, two of the four contacts of the main changeover switch circuit are normally closed.
The electrostatic high-voltage synchronous phase detection method according to claim 7 or 8. The ammeter group is:
When all the contact groups of the main changeover switch circuit are in the ON state, and the parallel breaker is turned on after establishing the voltage of the generator before connection with the bus,
If normal, the three phases show the highest value of the sum of the low-voltage microcurrents on the generator side and the bus side,
The electrostatic high-voltage synchronous phase detection method according to claim 7, 8 or 9. The electrostatic instrument transformer is:
When using an electrostatic insulator that forms a zero-phase voltage detection capacitor, it replaces the existing support insulator installed around the parallel breaker or uses it in addition.
The electrostatic high-voltage synchronous phase detection method according to claim 7, 8, 9, or 10.

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