JP2008199750A - Parallel operation connecting apparatus of power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parallel operation connecting apparatus of a power generator, in which a private connection terminal is not required when a plurality of power generators are connected by plugs and are operated in parallel, and output of the other power generator is prevented from appearing in a terminal of one plug as it is when it comes off. <P>SOLUTION: The parallel operation connecting apparatus of the power generator is provided with a conductive line 14 which connects at least two plugs Pa and Pb and at least one output electrical outlet Oe, and outputs of at least two power generators A and B, which are inputted through the at least two plugs Pa and Pb, to an electric load 12 through at least one output electrical outlet Oe, current sensors 16 (16a, 16b) which are arranged in the conductive line 14 and detect current flowing in the conductive line 14, and an interrupting device 20 interrupting the conductive line when current is not detected. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a generator parallel operation connection device, and more specifically to an apparatus for connecting a plurality of generators to perform parallel operation.

  When a plurality of generators are connected and operated in parallel, if the plug connected to one of the generators is removed, the output of the other generator will appear as it is at the terminal (blade). A connection terminal dedicated to parallel operation covered with an insulating cover was provided on the machine, and it was connected with a dedicated cable during parallel operation.

In addition, as described in Patent Documents 1 and 2 below, it is equipped with two plugs that can be connected to the output outlets of two generators and one output outlet that can be connected to an electrical load. In addition to the plug ground terminal, a dedicated ground terminal, full-wave rectifier circuit, etc. are provided, and the generator, plug ground terminal and dedicated ground terminal are closed. When the circuit is formed, in other words, when the plug is not removed, the relay is turned on by passing a low-voltage current from the full-wave rectifier circuit. The output of the other generator is prevented from appearing as it is at the terminal of the plug.
Japanese Patent No. 2869905 Japanese Patent No. 2947492

  In the above-described prior art, it is complicated in configuration and lacks versatility to provide a dedicated connection terminal for parallel operation that is covered with an insulating cover in advance on a generator. In addition, the techniques described in Patent Documents 1 and 2 are also difficult to avoid the same inconvenience in that a grounding terminal is required.

  Therefore, the object of the present invention is to solve the above-mentioned problems, and when a plurality of generators are connected in parallel with a plug, without requiring a dedicated connection terminal or the like, even when one of the plugs comes off, It is an object of the present invention to provide a generator parallel operation connecting device in which the output of the other generator does not appear as it is at the terminal (blade) of the disconnected plug.

  In order to solve the above-described problem, in claim 1, in the connection device for connecting at least two generators A and B and operating them in parallel, output outlets of the at least two generators A and B are provided. At least two plugs Pa and Pb connectable to Oa and Ob respectively, at least one output outlet Oe connectable to an electric load, the at least two plugs Pa and Pb, and the at least one output outlet Oe And the output of the at least two generators A and B input through the at least two plugs Pa and Pb is output to the electric load through the at least one output outlet Oe. A current sensor disposed in the conductive path and detecting a current flowing through the conductive path; and interrupting the conductive path when the current is not detected It was composed as and a disconnection device.

  In the generator parallel operation connecting device according to claim 1, at least two plugs Pa and Pb connectable to the output outlets Oa and Ob of at least two generators A and B, respectively, and an electric load A conductive path for connecting to at least one connectable output outlet Oe, a current sensor for detecting a current flowing through the conductive path, and a shut-off device for cutting off the conductive path when the current is not detected are provided. Since the current is not detected when one of the plugs is removed, the conductive path is cut off, so that the other plug's terminal (blade) does not require a dedicated connection terminal and the other power generation It is possible to prevent the output of the machine from appearing as it is. Moreover, since a dedicated connection terminal or the like is not required, the configuration is simple, and it is possible to connect to an ordinary generator that does not have a dedicated connection terminal.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best mode for carrying out a generator parallel operation connecting apparatus according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a block diagram generally showing a generator parallel operation connecting apparatus according to an embodiment of the present invention.

  As shown in the figure, a generator parallel operation connecting device (denoted by reference numeral 10) is a connecting device for connecting at least two generators A and B to operate them in parallel. The two generators A and B are both generators driven by an internal combustion engine (not shown). For example, single-phase AC100V / 200V generates an AC output of about 4.5 kVA.

  The generators A and B are provided with output outlets Oa and Ob for taking out their outputs. The output terminals Oa and Ob include voltage terminals Oa1 and Oa2 or Ob1 and Ob2, a single-phase three-wire terminal including a neutral terminal Oa3 or Ob3 in between, and ground terminals Oa4 and Ob4.

  The apparatus 10 includes at least two plugs Pa and Pb that can be connected to the output outlets Oa and Ob of the two generators A and B, at least one output outlet Oe that can be connected to the electrical load 12, and 2 Conductive path 14 that connects the plugs Pa and Pb and the output outlet Oe, and outputs the output of the generators A and B input through the two plugs Pa and Pb to the electric load 12 through the output outlet Oe. A current sensor 16 that is connected to the conductive path 14 and generates an output when current flows from one of the plugs Pa and Pb to the other, and a blocking device 20 that blocks the conductive path 14 when the current sensor 16 does not generate an output. Prepare.

  These will be described individually below.

  Plugs Pa and Pb correspond to the output outlets Oa and Ob of the generators A and B, and are single-phase three-wire terminals composed of voltage terminals Pa1, Pa2 or Pb1, Pb2, and neutral terminals Pa3 or Pb3 in between. A ground terminal Pa4 or Pb4 is provided. The structures of the plugs Pa and Pb and the output outlets Oa and Ob of the generators A and B are known and general.

  Similarly to the output outlets Oa and Ob on the generator side, the output outlet Oe of the device 10 includes a single-phase three-wire terminal including a voltage terminal Oe1 and Oe2, a neutral terminal Oe3 in between, and a ground terminal Oe4. The output outlet Oe is connected to the electric load 12 by inserting a plug (not shown) of the electric load 12.

  A conductive path that connects two plugs Pa, Pb and an output outlet Oe, and outputs the output of the generators A, B input via the two plugs Pa, Pb to the electric load 12 via the output outlet Oe. 14, voltage lines 14 a 1 and 14 b 1 that connect the high voltage sides of both voltage terminals, low voltage lines 14 a 2 and 14 b 2 that connect the low voltage sides of the voltage terminals, and neutral terminals that connect the neutral terminals. It consists of wires 14a3 and 14b3 and ground wires 14a4 and 14b4 that connect the ground terminals.

  The voltage lines 14a1, 14b1, the low-voltage lines 14a2, 14b2, the neutral lines 14a3, 14b3, and the ground lines 14a4, 14b4 are connected (joined) at the connection point 14c. The wires 14a2, the neutral wire 14a3, and the ground wire 14a4 are collected, and the combined power generation output of the two generators A and B is output to the output outlet Oe through them.

  The ground wires 14a4 and 14b4 are grounded to the housings (not shown) of the generators A and B via the second ground terminals 14a5 and 14b5 on the input side, and the third ground terminal 14e on the output side. And grounded to the housing (not shown) of the apparatus 10.

  In the conductive path 14, a main switching device 22 is inserted upstream of the connection point 14c, and a leakage breaker 24 is inserted downstream thereof. Current sensors 16 a and 16 b are arranged on the upstream side of the main switching device 22 in the conductive path 14, more specifically, the voltage lines 14 a 1 and 14 b 1 in the conductive path 14. The current sensors 16 a and 16 b are connected to the interruption device 20. An operating power generation circuit 26 that generates an operating power source such as the shut-off device 20 is connected downstream of the main switching device 22.

  The main switchgear 22 includes a relay 22a. The relay 22a includes a coil 22a1 and a contact 22a2 interposed between the voltage lines 14a1, 14b1, 14a2, and 14b2. The contact 22a2 of the relay 22a is normally closed, and as long as the coil 22a1 is demagnetized, it is closed and sends the outputs of the generators A and B to the output outlet Oe.

  On the other hand, when the coil 22a1 is excited, the contact 22a2 is opened (the conductive path 14 is interrupted), and the supply of the output of the generators A and B to the output outlet Oe is blocked. The contact 22a2 can be opened and closed manually. In addition, the coil 22b arrange | positioned upstream of the contact 22a2 in the main switchgear 22 is for an electrical leakage detection. The coil 22a1 of the relay 22a of the main switchgear 22 is connected to the shut-off device 20 via connectors 22c and 22d.

  The earth leakage breaker 24 also has a structure similar to the main switchgear 22, and when the electric load 12 is overloaded due to earth leakage or the like, the voltage lines 14a1 and 14a2 are interrupted. However, since the structure and operation are known, Description is omitted. Note that double circles on both sides of the main switching device 22 and the earth leakage breaker 24 indicate terminals.

  FIG. 2 is a circuit diagram showing a configuration of the operation power supply generation circuit 26.

  The operating power generation circuit 26 includes a transformer 26a, and the voltage AC200V between terminals of the voltage lines 14a1 and 14a2 is stepped down to AC10V by the transformer 26a. A rectifier circuit 26b is connected to the transformer 26a, and the transformer output that has been stepped down to AC10V is converted into a direct current of about DC12V by the rectifier circuit 26b and output from the first operating voltage terminal 26c.

  A voltage regulator 26d is connected to the rectifier circuit 26b, and the output of the rectifier circuit converted to DC12V is stepped down to DC5V by the voltage regulator 26d and output from the second operating voltage terminal 26e. As shown in FIG. 1, the operating power supply generation circuit 26 is connected to the conductive path 14 and the breaking device 20 via connectors 26f and 26g.

  FIG. 3 is a circuit diagram showing configurations of the current sensor 16 and the interrupting device 20.

  The current sensor 16a includes a current transformer 16a1 disposed on the voltage line 14a1, and the current obtained through the current transformer 16a1 is converted into a direct current by the rectifier circuit 16a2 and then input to the positive phase input terminal of the operational amplifier 16a3. Then, the voltage is compared with the reference voltage input from the negative phase input terminal.

  Similarly, the current sensor 16b also includes a current transformer 16b1 disposed on the voltage line 14b1, and the current obtained through the current transformer 16b1 is converted into a direct current by the rectifier circuit 16b2, and then the positive phase input terminal of the operational amplifier 16b3. Is compared with the reference voltage input from the negative phase input terminal.

  A reference voltage obtained by dividing the output of the second operating power supply terminal 26e with a resistor is input to the negative phase input terminals of the operational amplifiers 16a3 and 16b3. The reference voltage is set to a value that can determine whether or not a current flows through the voltage lines 14a1 and 14b1. The operational amplifiers 16a3 and 16b3 generate an L level output when the input value from the positive phase input terminal is equal to or lower than a reference voltage input from the negative phase input terminal, and generate an H level output when exceeding the reference voltage.

  The cutoff device 20 includes an EX-OR (exclusive OR) circuit 20a and a transistor 20b. The outputs of the operational amplifiers 16a3 and 16b3 are input to the EX-OR circuit 20a. The EX-OR circuit 20a generates an H level output only when an H level output is input from any one of the operational amplifiers 16a3 and 16b3.

  The output of the EX-OR circuit 20a is connected to the base terminal of the transistor 20b. The transistor 20b is of an npn type, and its emitter terminal is connected to the first operating voltage terminal 26c via the coil 22a1 of the relay 22a of the main switch 22 described above, while its collector terminal is grounded.

  The operational amplifier 16a3, 16b3 of the current sensor 16 and the EX-OR circuit 20a of the cutoff device are applied with the voltage of the second operating voltage terminal 26e as the operating voltage.

  Next, the operation of the apparatus 10 according to this embodiment will be described.

  After the generators A and B are driven by the internal combustion engine to start power generation, the plugs Pa and Pb are inserted into the output outlets Oa and Ob of the generators A and B, and a plug (not shown) of the electric load 12 is connected. The parallel operation of the generators A and B is started by being inserted into the output outlet Oe. The outputs of the generators A and B are combined by the device 10 and supplied to the electric load 12. When the generators A and B are operated in parallel, the generators A and B are operated synchronously so that the magnitudes of the output voltages are equal, the frequencies of the output voltages are equal, and the phases of the output voltages are equal.

  In the parallel operation, one of the plug Pa connected to the generator A via the output outlet Ob and the plug Pb connected to the generator B via the output outlet Ob, for example, the plug Pb is mistakenly connected from the output outlet Ob. If it is detached (withdrawn), the output generated by the generator A may appear as it is at the voltage terminals Pb1 and Pb2 of the plug Pb.

  Referring to FIG. 3, as long as the plugs Pa and Pb are connected to the output outlets Oa and Ob of the generators A and B that are operated in parallel, the outputs of the generators A and B are connected to the voltage lines 14a1 and 14b1. Since current flows through the output outlet Oe, the current sensors 16a and 16b generate outputs, and the outputs are rectified and sent to the operational amplifiers 16a3 and 16b3, which generate an H level output.

  In addition, when the generators A and B are operated in parallel, their power generation outputs are always in an unbalanced state although they are very small. Therefore, the voltage lines 14a1 and 14b1 have a reactive circulation current called a cross current from one of the plugs Pa and Pb to the other. However, since the current due to the generator output is larger, the current sensors 16a and 16b generate outputs mainly according to the current due to the generator output.

  The H level outputs of the operational amplifiers 16a3 and 16b3 are input to the EX-OR circuit 20a. The EX-OR circuit 20a produces an L level output when both input values are at an H level, which is output to the transistor 20b. Therefore, the transistor 20b does not conduct, and therefore the relay 22a of the main switching device 22 does not conduct. The coil 22a1 is not excited, the contact 22a2 remains closed, and the conductive path 14 is not interrupted.

  On the other hand, when one of the plugs Pa, Pb, for example, the plug Pb is dropped (unplugged) from the output outlet Ob of the generator B, the output of the generator B does not flow through the voltage line 14b1, so the current sensor 16b outputs the output. The output of the operational amplifier 16b3 also becomes L level. On the other hand, since the plug Pa is connected to the output outlet Oa of the generator A, the output of the operational amplifier 16a3 remains at the H level.

  Therefore, the EX-OR circuit 20a generates an H level output when one of the input values is at the L level, and outputs it to the transistor 20b. Therefore, the transistor 20b is turned on, and the first operation power supply terminal 26c. The coil 22a1 of the relay 22a is energized to open the contact 22a2.

  As a result, the conductive path 14 is cut off and the input from the generator A is also cut off. Therefore, it is possible to prevent the output generated by the generator A from appearing as it is at the voltage terminals Pb1 and Pb2 of the plug Pb.

  In this embodiment, as described above, in the connection device 10 for connecting at least two generators A and B and operating them in parallel, the output outlets Oa and Ob of the at least two generators A and B can be connected respectively. At least two plugs Pa, Pb, at least one output outlet Oe connectable to the electrical load 12, and the at least two plugs Pa, Pb and at least one output outlet Oe are connected, and the at least two A conductive path 14 for outputting the outputs of the at least two generators A and B inputted through the plugs Pa and Pb to the electric load 12 through the at least one output outlet Oe; A current sensor 16 (16a, 16b) that is disposed in the path 14 and detects a current flowing through the conductive path 14, and when the current is not detected, Since it is configured to include the blocking device 20 that blocks the conductive path, the current is not detected when one of the plugs Pa and Pb is disconnected, so the conductive path 14 is blocked, and thus a dedicated connection terminal is required. Thus, it is possible to prevent the output of the other generator from appearing as it is at the terminal (blade) of the disconnected plug. Moreover, since a dedicated connection terminal or the like is not required, the configuration is simple, and it is possible to connect to an ordinary generator that does not have a dedicated connection terminal.

  In the above-described embodiment, the case where two generators A and B are operated in parallel has been described. However, the present invention is also applicable when three or more generators are operated in parallel. Referring to FIG. 3, if a third current sensor is arranged on the voltage line of the third generator and its operational amplifier is connected to the base terminal of the transistor 20b in parallel with the EX-OR circuit 20a. good.

  In the above description, the shut-off device 20 is configured by an electronic circuit, but the transistor 20b may be operated using a microcomputer or the like.

It is a block diagram which shows generally the parallel operation connection apparatus of the generator which concerns on the Example of this invention. FIG. 2 is a circuit diagram illustrating a configuration of an operation power generation circuit in the apparatus illustrated in FIG. 1. It is a circuit diagram which shows the structure of the current sensor and interruption | blocking apparatus in the apparatus shown in FIG.

Explanation of symbols

  10 generator parallel operation connection device, 12 electrical load, 14 conductive path, 14a1, 14a2, 14b1, 14b2 voltage line, 14a3, 14b3 neutral wire, 14a4, 14b4 ground wire, 16 current sensor, 20 interrupting device, 20a EX -OR circuit, 20b transistor, 22 main switchgear, 22a relay, 22a1 coil, 22a2 contact, 24 earth leakage breaker, 26 operating power generation circuit

Claims (1)

  In a connecting device for connecting at least two generators A and B and operating them in parallel, at least two plugs Pa and Pb that can be connected to output outlets Oa and Ob of the at least two generators A and B, respectively, The at least one output outlet Oe that can be connected to an electric load, the at least two plugs Pa and Pb, and the at least one output outlet Oe are connected and input via the at least two plugs Pa and Pb. A conductive path that outputs the output of the at least two generators A and B to the electric load via the at least one output outlet Oe, and a current that is disposed in the conductive path and that flows through the conductive path. A parallel operation of a generator comprising: a current sensor to detect; and a shut-off device that shuts off the conductive path when the current is not detected Connection devices.

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