JP2012244693A - Parallel operation controller of inverter generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a parallel operation controller of an inverter generator configured so that a desired output can be obtained even if it is connected arbitrarily with an output terminal, when a plurality of inverter generators outputting three-phase AC are operated in parallel.SOLUTION: In an inverter generator comprising first, second and third inverters 22a, 22b, 22c each connected with three windings wound around an engine-driven power generation part and outputting an AC power by performing DC/AC conversion of an output AC power by using switching elements, and first, second and third control units performing on/off control of these switching elements, and can be operated in parallel with an inverter generator 10B of the same configuration, the phase of a single-phase AC power input from the generator 10B is determined when the output terminal is connected arbitrarily with that of the generator 10B, and on/off of the switching elements are controlled so that the AC outputs have predetermined phases and output orders with reference to any one of the single-phase AC thus determined.

Description

  The present invention relates to a parallel operation control device for an inverter generator, and more particularly to a parallel operation control device for a generator that enables parallel operation of an inverter generator that outputs a three-phase alternating current.

  As for the parallel operation of the inverter generator that outputs three-phase alternating current, for example, the technique described in Patent Document 1 below can be cited. In the technique described in Patent Document 1, the output phases of the generators operated in parallel are automatically matched.

Japanese Patent No. 3363170

  In the technique described in Patent Document 1, it is necessary to accurately connect the output terminals of the inverter generators operated in parallel according to the output phase relationship, and the procedure is cumbersome, and the connection terminals are mistakenly connected. If this happens, the desired output cannot be obtained.

  Therefore, the object of the present invention is to solve the above-mentioned problems, and when operating a plurality of inverter generators that output three-phase alternating current in parallel, an inverter that can obtain a desired output even if an output terminal is arbitrarily connected. The object is to provide a parallel operation control device for a generator.

  In order to solve the above-described problem, in the parallel operation control apparatus for an inverter generator according to claim 1, the first, second and third windings wound around the power generation unit driven by the engine are respectively provided. First, second, and third inverters that are connected and that convert alternating current output from the first, second, and third windings into direct current / alternating current using a switching element to output alternating current power; and The first, second, and third control units that control ON / OFF of the switching elements of the first, second, and third inverters and that are communicably connected to each other, and the first, second, and third units A terminal group that is connected to each inverter and outputs the AC output as one of the U-phase, V-phase, and W-phase, and an output terminal that is connected to the neutral terminal of each of the terminal groups; And at least one inverter generator B Inverter generator A that can be operated in parallel with phase AC output, wherein the first, second, and third control units are configured such that the terminal group of the output terminal is connected to the terminal group of the output terminal of the generator B, respectively. Is connected to the first, second, and third inverters from the generator B, and any one of the determined single-phase alternating currents is determined. Is used to control ON / OFF of the switching elements of the first, second, and third inverters so that the single-phase AC outputs of the first, second, and third inverters are in a predetermined phase and output order. It was configured as follows.

  In the inverter generator parallel operation control device according to claim 2, the first, second, and third control units are input from the generator B to the first, second, and third inverters. An inter-phase voltage / inter-phase current detecting means for detecting an inter-phase voltage and an inter-phase current, respectively, and on / off of switching elements of the first, second and third inverters so as to be synchronized with the detected inter-phase voltage and inter-phase current It was constituted so as to control.

  In the inverter generator parallel operation control apparatus according to claim 3, the first, second, and third control units of the generator B are configured based on the output from the first inverter that constitutes the master. 2. The on / off state of the switching element is controlled so that the phase of the output of the third inverter becomes a target value.

  In the parallel operation control apparatus for an inverter generator according to claim 4, the first control unit of the generator B generates a reference signal and also generates a synchronization signal having a predetermined phase with respect to the reference signal. To the second and third control units, and thus the first, second and third control units are based on the output from the first inverter constituting the master based on the reference signal and the synchronization signal. The on / off of the switching element is controlled so that the phase of the output of the second and third inverters becomes a target value.

  In the inverter generator parallel operation control apparatus according to claim 5, the terminal group of the first, second, and third inverters includes any one of the U-phase, V-phase, and W-phase, and the neutral terminal. The output terminal is configured to be a three-phase four-wire system connected to the terminal group and the neutral terminal.

  In the inverter generator parallel operation control apparatus according to claim 6, the first, second, and third control units output the first, second, and third inverters of the generator B. Switching between the first, second, and third inverters so as to correct at least one of the voltage amplitude amount and the voltage phase amount of the AC output when different from the outputs of the corresponding first, second, and third inverters. The device is configured to control on / off of the element.

  In the parallel operation control apparatus for an inverter generator according to claim 1, the inverter generator is connected to the first, second, and third windings wound around the power generation unit driven by the engine, and outputs from them. ON / OFF of the first, second, and third inverters, and the first, second, and third inverters that output AC power by DC / AC conversion using switching elements. In addition, the first, second, and third control units connected to each other so as to communicate with each other, and the first, second, and third inverters are connected to the AC outputs for the U-phase, V-phase, and W-phase, respectively. Inverter generator having a terminal group that outputs as either one and an output terminal connected to each of the neutral terminals, and capable of operating in parallel with at least one inverter generator B having the same configuration and three-phase AC output A, no. The second and third control units are connected to the first, second, second from the generator B when the terminal groups of the output terminals are arbitrarily connected to the terminal groups of the output terminals of the generator B via connection cables, respectively. The phase of the single-phase AC input to the three inverters is discriminated, and the single-phase AC output of the first, second, and third inverters has a predetermined phase and output order based on any one of the discriminated single-phase ACs. Since the switching elements of the first, second, and third inverters are controlled to be turned on and off, the output terminal group is arbitrarily connected to the output terminal group of the generator B. In other words, even when the U-phase and V-phase terminals, the V-phase and W-phase terminals, and the W-phase and U-phase terminals are connected, the phase of the output single-phase AC is determined, and the determined single-phase AC Any one of the first, second, and third inverters, for example, U phase AC By controlling on / off of the switching elements of the first, second, and third inverters so that the AC output is in a predetermined phase and output order, three-phase AC can be generated no matter how the output terminals are connected. A plurality of inverter generators for output, for example, two, can be operated in parallel.

  Further, the interphase voltage and interphase current input from the generator B to the first, second, and third inverters are detected, respectively, and the first, second, and third are synchronized with the detected interphase voltage and correlation current. It is also possible to control the ON / OFF of the switching element of the inverter, thereby causing an unbalanced load state other than a three-phase load, for example, a load where the interphase output is unbalanced, such as when power is supplied to a single-phase load. Even in the state, parallel operation can be realized independently without affecting the output of other phases, and an increase in unbalance current during parallel operation and a cross current with the counterpart machine can be reliably avoided.

  In the inverter generator parallel operation control apparatus according to claim 2, the first, second, and third control units include the interphase voltage input from the generator B to the first, second, and third inverters. An interphase voltage / interphase current detection means for detecting the interphase current is provided, and the on / off of the switching elements of the first, second, and third inverters is controlled so as to be synchronized with the detected interphase voltage and interphase current. Therefore, in addition to the effects described above, the voltage and phase of the three-phase alternating current output from each of the first, second, and third inverters can be accurately matched.

  In the parallel operation control apparatus for an inverter generator according to claim 3, the first, second and third control units of the generator B are the second, based on the output from the first inverter constituting the master. Since the on / off of the switching element is controlled so that the phase of the output of the third inverter becomes the target value, in addition to the above-described effects, the three outputs output from each of the first, second, and third inverters. Phase AC voltage and phase can be matched more accurately.

  In the inverter generator parallel operation control apparatus according to claim 4, the first control unit of the generator B generates a reference signal and also generates a synchronization signal having a predetermined phase with respect to the reference signal. The first, second and third control units transmit to the second and third control units, so that the second and third inverters are based on the output from the first inverter constituting the master based on the reference signal and the synchronization signal. In addition to the above-described effects, the three-phase alternating current output from each of the first, second, and third inverters is controlled. The voltage and phase can be matched more accurately.

  In the inverter generator parallel operation control apparatus according to claim 5, the terminal group of the first, second, and third inverters is a single phase composed of any one of the U phase, the V phase, and the W phase and a neutral terminal. In addition to the effects described above, the output terminal is configured as a three-phase four-wire system that is connected to the terminal group and the neutral terminal. A plurality of inverter generators can be operated in parallel.

  In the inverter generator parallel operation control device according to claim 6, the first, second, and third control units are configured so that the outputs of the first, second, and third inverters correspond to the generator B. When the output is different from the output of the first, second, and third inverters, the switching elements of the first, second, and third inverters are turned on / off so as to correct at least one of the voltage amplitude amount and the voltage phase amount of the AC output. In addition to the above-described effects, a plurality of inverter generators can be reliably operated in parallel.

It is a block diagram which shows the inverter generator which concerns on the Example of this invention. It is a top view of the crankcase of the engine of the inverter generator of FIG. It is a circuit diagram which shows the structure of the inverter part of the inverter generator of FIG. 1 in detail. It is explanatory drawing explaining operation | movement of the inverter part of the inverter generator of FIG. It is a circuit diagram which shows the structure of the filter part of the inverter generator of FIG. 1 in detail. Similarly, it is a circuit diagram showing in detail the configuration of the filter section of the inverter generator of FIG. It is explanatory drawing which shows operation | movement of the engine control part of the inverter generator of FIG. It is a block diagram which shows more concretely the operation | movement of the control part of the inverter part of the inverter generator of FIG. FIG. 9 is a time chart for explaining a reference signal and a synchronization signal used in the configuration of FIG. 8. FIG. 8 is a time chart showing switching from three-phase output to single-phase output by the operation of FIG. 7. FIG. 8 is a time chart showing switching from single-phase output to three-phase output by the operation of FIG. 7. It is a perspective view of an inverter generator which shows the case where two inverter generators of FIG. 1 are operated in parallel. It is a block diagram which shows operation | movement of the control part of an inverter part when carrying out the parallel operation of the two inverter generators shown in FIG. 13 is a flowchart showing the operation of the control unit of the inverter unit when the two inverter generators shown in FIG. 12 are operated in parallel. FIG. 13 is a diagram showing an output waveform when the two inverter generators shown in FIG. 12 are operated in parallel. 13 is a flow chart showing the operation of the control unit of the inverter unit when the two inverter generators shown in FIG. 12 are similarly operated in parallel.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment for carrying out the operation of an inverter generator parallel operation control device according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram generally showing an inverter generator according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes an inverter generator. The inverter generator 10 includes an engine (internal combustion engine) 12 and has a rated output of about 5 kW (50 A at 100 V AC). The engine 12 is a spark ignition type air-cooled engine using gasoline as fuel.

  A throttle valve 12b and a choke valve 12c are disposed in the intake pipe 12a of the engine 12. The throttle valve 12b is connected to a step (throttle) motor 12d. The choke valve 12c is also connected to a choke motor (also comprising a step motor) 12e.

  The engine 12 includes a battery 14 having a capacity of about 12V, and when the step motor 12d and the choke motor 12e are energized from the battery 14, the throttle valve 12b and the choke valve 12c are driven to open and close. The engine 12 includes a power generation unit (shown as “ALT”) 16.

  FIG. 2 is a plan view of the crankcase 12f of the engine 12 shown in FIG.

  As shown in the figure, the power generation unit 16 includes a stator 16a fixed to the crankcase 12f and a rotor 16b that also serves as a flywheel and is rotatably disposed around the stator 16a.

  The stator 16a includes 30 protrusions, 27 of which 3 sets of three-phase output windings (main windings) 18 composed of U, V, and W phases are wound, and 3 Similarly, a set of three-phase output windings (sub-windings) 20 consisting of U, V, and W are wound. Three sets of output windings 18 consist of 18a, 18b and 18c.

  Inside the rotor 16b arranged outside the stator 16a, a plurality of pairs of permanent magnets 16b1 are alternately attached to the magnetic poles magnetized in the radial direction so as to face the output windings 18 and 20.

  In the power generation unit 16, the permanent magnet of the rotor 16b rotates around the stator 16a, so that the U-phase and V-phase are output from the 27 three-phase output windings 18 (more specifically, 18a, 18b, and 18c). The AC power composed of the W phase is output (power generation), and the AC power of each phase is similarly output from the three sub-windings 20.

  Returning to FIG. 1 and continuing the description, the inverter generator 10 according to this embodiment is roughly divided into an output winding 18 wound around the power generation unit 16, an inverter unit (indicated as "INV") 22, , A filter unit (shown as “Filter”) 24, an output unit (shown as “OUT”) 26, an engine control unit (shown as “ECU”) 28, and a control panel unit (shown as “Control Panel”) 30. Is provided. ECU (Electronic Control Unit) means an electronic control unit and includes a CPU as described later.

  As shown in the figure, the characteristic of the inverter generator 10 according to this embodiment is that three sets (three) of single-phase inverter generators (inverters) are connected in parallel, and the desired voltage and phase are output from the output. The three-phase alternating current and single-phase alternating current can be selectively and reliably output.

  That is, the inverter generator 10 includes three sets of windings composed of first, second, and third output windings 18a, 18b, and 18c connected in parallel, and first, second, and third inverters (inverters). Part or inverter generator) 22a, 22b, 22c provided with three sets of inverters, and first, second and third filters 24a, 24b, 24c provided with three sets of filters 24 And an output unit 26 having a three-phase output terminal 26e and a single-phase output terminal 26f, an engine control unit 28 for controlling the operation of the engine 12, and a single control panel unit 30.

  Specifically, the inverter unit 22 and the like are composed of a semiconductor chip mounted on a printed board housed in a case provided at an appropriate position of the engine 12, and the control panel unit 30 is positioned at an appropriate position of the engine 12. And a panel connected to the semiconductor chip.

  As shown in the figure, the output winding 18, the inverter unit 22, the filter unit 24, and the output unit 26, each having three sets, are connected to each other with the sets having common subscripts a, b, and c. Configured as follows.

  The first, second, and third inverters 22a, 22b, and 22c constituting the inverter unit 22 are each composed of a single-phase two-wire inverter, and an FET (field effect transistor) and SCR (thyristor) integrated power module. 22a1, 22b1, 22c1, 32-bit CPUs 22a2 (first control unit), 22b2 (second control unit), 22c2 (third control unit), and interphase voltage / interphase for detecting the interphase voltage and interphase current of the power generation output Current sensors 22a3, 22b3, and 22c3 are provided. The CPUs 22a2, 22b2, and 22c2 are connected to each other via a communication line 28d so that they can communicate with each other.

  FIG. 3 is a circuit diagram showing the configuration of the inverter unit 22 in detail. Hereinafter, the group a will be described as an example, but the configuration of each group is basically the same, and therefore the description of the group a is valid for the groups b and c.

  As shown in FIG. 3, the power module 22a1 includes a mixed bridge circuit 22a11 in which three SCRs (thyristors (switching elements for DC conversion)) and DI (diodes) are bridge-connected, and four FETs (field effect transistors). (Switching element for AC conversion) is configured from an H-bridge circuit 22a12 that is H-bridge connected.

  Three-phase AC power output (generated) from the U-phase winding 18a, V-phase winding 18b, and W-phase winding 18c of the output winding 18 wound around the power generation section 16 is supplied to the corresponding first inverter 22a. And is input to the midpoint of the SCR and DI in the mixed bridge circuit 22a11 of the power module 22a1.

  In the mixed bridge circuit 22a11, the gate of the SCR is connected to the battery 14 via a driver circuit (not shown). Energization (ON, conduction (ignition)) and energization stop (OFF (non-conduction)) from the battery 14 via the driver circuit are controlled by the CPU 22a2.

  That is, the CPU 22a2 conducts (ignites) the SCR gate at a conduction angle (ignition angle) corresponding to the target output voltage based on the output of the interphase voltage / interphase current sensor 22a3, and inputs from the output winding 18a. Is converted to a direct current of the output voltage.

  The DC output from the mixing bridge circuit 22a11 is input to the H bridge circuit 22a12 of the FET. In the H-bridge circuit 22a12, the FET is connected to the battery 14, and the energization (ON (conduction)) and energization stop (OFF (non-conduction)) are controlled by the CPU 22a2, so that the input direct current The output is converted into alternating current at a predetermined frequency (for example, a commercial frequency of 50 Hz or 60 Hz).

  FIG. 4 is an explanatory diagram for explaining the operation of the H-bridge circuit 22a12.

  That is, the CPU 22a2 generates and generates a reference sine wave (signal wave, indicated by a solid line at the top) of a predetermined frequency (that is, commercial frequency 50 Hz or 60 Hz) of the target output voltage waveform as shown in FIG. A reference sine wave is input, and a comparator (not shown) is compared with a carrier (for example, a 20 kHz carrier wave) to generate a PWM (Pulse Width Modulation) signal, and an H bridge is generated based on the generated PWM signal. The FET of the circuit 22a12 is turned on / off.

  In FIG. 4, the broken line at the bottom shows the target output voltage waveform. The period T (step) of the PWM signal (PWM waveform) is actually much shorter, but is exaggerated in the figure for convenience of understanding.

  The inverter unit 22 is connected to the filter unit 24.

  The filter unit 24 includes LC filters (low-pass filters) 24a1, 24b1, and 24c1 for removing harmonics and noise filters 24a2, 24b2, and 24c2 for removing noise, and the AC output converted by the inverter unit 22 is an LC filter 24a1. , 24b1, 24c1 and noise filters 24a2, 24b2, 24c2 to remove harmonics and noise.

  FIG. 5 shows a circuit configuration of the LC filter 24a1, and FIG. 6 shows a circuit configuration of the noise filter 24a2. Although not shown, the circuit configurations of the LC filters 24b1 and 24c1 and the noise filters 24a2, 24b2, and 24c2 are the same.

  The inverter unit 22 is connected to the output unit 26 via the filter unit 24.

  As shown in FIG. 1, the output unit 26 is connected to the first, second, and third inverters 22a, 22b, and 22c, respectively, and outputs an AC output as one of the U phase, V phase, and W phase. 26a, 26b, 26c and a neutral terminal 26d of the terminal group are connected in series to a three-phase output terminal (output terminal) 26e, connected in parallel to the terminal group, and connected in series to the neutral terminal. Single-phase output terminal (output terminal) 26f.

  More specifically, the output unit 26 is connected to the first inverter 22a and outputs an AC output as a U phase, and is connected to the second inverter 22b and outputs an AC output as a V phase. The V-phase terminal 26b1, the W-phase terminal 26c1 connected to the third inverter 22c and outputting the AC output as the W-phase, and the neutral points 26a2, 26b2, and 26c2 of the first, second, and third inverters. A three-phase output terminal 26e (four wires) connected in series to a neutral O-phase terminal 26d.

  Further, the output unit 26 is connected in parallel to the U-phase terminal 26a1, the V-phase terminal 26b1, and the W-phase terminal 26c1, and is connected in series to the O-phase terminal 26d (two-wire) single-phase output terminal 26f; A switching mechanism 26g for switching between the three-phase output terminal 26e and the single-phase output terminal 26f is provided.

  The three-phase output terminal 26e and the single-phase output terminal 26f are connected to the electric load 32 via a connector (not shown).

  Similarly, the engine control unit 28 includes a 32-bit CPU 28c to control the operation of the engine 12, and the CPUs 22a2, 22b2, and 22c2 of the inverters 22a, 22b, and 22c, a CAN (Control Area Network) BUS (bus) 28a, and a CAN / The CPU 22a2, 22b2, and 22c2 (first, second, and third control units) are communicably connected to each other through an F (Interface) 28b. The output of the output winding (sub-winding) 20 is supplied to these CPUs 22a2, 22b2, 22c2, and 28c as operating power.

  The engine control unit 28 includes a starter generator driver (STG DRV) 28d that operates the output winding 18c as a starter (starter) of the engine 12 in addition to the operation as a generator (generator). That is, in this embodiment, the power generation unit 16 is also operated as an electric motor by energizing any one of the output windings 18a, 18b, and 18c (for example, the output winding 18c).

  The starter generator driver 28d includes a DC / DC converter 28d1. As will be described later, the DC / DC converter 28d1 boosts the output of the battery 14 to about 200V and energizes the output winding 18c in accordance with an instruction from the CPU 28c, and rotates the rotor 16b of the power generation unit 16 relative to the stator 16a. Then, the engine 12 is started.

  The engine control unit 28 further includes a TDC circuit (not shown) for detecting TDC from the output of a pulser (not shown) comprising a magnetic pickup disposed between the stator 16a and the rotor 16b, and a U of the output winding 18c. A rotational speed detection circuit 28e is connected to the terminal and detects the rotational speed of the engine 12 from its output.

  The engine control unit 28 further drives a communication (COM) I / F 28f, a sensor (Sensor) I / F 28g, a display (DISP) I / F 28h, a SW (switch) I / F 28i, and a step motor 12d. Driver circuit 28j, driver circuit 28k for driving choke motor 12e, and ignition driver circuit 28l for driving an ignition device (not shown).

  The CPU 28c determines the opening degree of the throttle valve 12b so that the target rotational speed is calculated according to the AC output to be supplied to the electric load 32, and supplies it to the step motor 12d via the driver circuit 28j. To control.

  The control panel unit 30 is provided separately from the engine 12, and is connected to a remote control box (not shown) that can be carried by the user via a wireless (or wired) wireless (remote) I / F 30a, and an LED 30b. And an LCD 30c, a KEY switch (main switch) 30d for instructing operation (start) / stop of the inverter generator 10 that can be operated by the user, and between the three-phase AC and the single-phase AC of the output of the inverter generator 10 Is provided with a three-phase / single-phase changeover switch 30e.

  The control panel unit 30 and the engine control unit 28 are communicably connected via wireless (or wired), and the engine control unit 28 outputs the outputs of the KEY switch 30d and the changeover switch 30e of the control panel unit 30 via the switch I / F 28i. To control the blinking of the LED 30b and the LCD 30c of the control panel unit 30 via the display I / F 28h.

  FIG. 7 is an explanatory diagram for explaining the operation of the engine control unit 28.

  As described above, since the present invention can selectively and reliably output a three-phase alternating current and a single-phase alternating current of a desired voltage, in this embodiment, the inverter unit 22 is divided into three sets of single-phase inverters (first 1, second and third inverters) 22 a, 22 b, 22 c, and the CPU 28 c of the engine control unit 28 operates the switching mechanism 26 g of the output unit 26 in accordance with the output of the changeover switch 30 e to provide a three-phase output terminal And single-phase output terminal.

  Further, in the inverter unit 22, one of the three sets of single-phase inverters 22a, 22b, and 22c, for example, 22a is a master and the remaining is a slave, and three sets of single-phase inverters are used according to communication from the CPU 28c of the engine control unit 28. When the CPUs 22a2, 22b2, and 22c2 of the inverter output a three-phase alternating current, as shown in the figure, based on the output from the U-phase output unit 26a on the master side, the V-phase and W from the slave-side 26b and 26c, W The operation of the inverter unit 22 is controlled so as to shift the phase of the phase output by 120 degrees.

  On the other hand, when it is determined that switching to single-phase alternating current is instructed, the CPUs 22a2, 22b2, and 22c2 respond to communication from the CPU 28c and the slave side 26b is based on the output from the U phase terminal 26a on the master side. , 26c controls the operation of the inverter unit 22 so that the V-phase and W-phase outputs are synchronized with the U-phase, and outputs a single-phase alternating current from the single-phase output terminal 26f.

  FIG. 8 is a block diagram showing the operation of the three sets of CPUs 22a2, 22b2, and 22c2, more specifically, the operation of the generator self-sustaining operation control. FIG. 9 shows the reference signal and the synchronization signal used in the operation of FIG. It is a time chart to explain.

  As shown in the figure, the CPU 22a2 of the first inverter 22a on the master side includes a reference signal generator 22a21 that generates a reference signal of a predetermined frequency (shown in FIG. 9), and a PWM controller 22a22 that performs PWM control according to the PWM signal of FIG. Synchronized signals 1 and 2 (shown in FIG. 9) for synchronizing the output phase on the slave side with that on the master side (having a predetermined phase with respect to the reference signal) and transmitting them to the CPUs 22b2 and 22c2. The signal control part 22a23 and the communication control part 22a24 which controls transmission / reception (communication) of the synchronous signal produced | generated via the communication line 22d are provided.

  The second and third inverters 22b and 22c on the slave side also include similar PWM control units 22b22 and 22c22, synchronization signal control units 22b23 and 22c23, and communication control units 22b24 and 22c24, except for the reference signal generation unit. .

  When the three-phase alternating current is instructed (switched) via the changeover switch 30e, the synchronization signal control unit 22a23 has a predetermined frequency (FIG. 9A), for example, when the frequency is decreased (FIG. 9A). Even in (b)), the synchronization signals 1 and 2 are always generated and transmitted whose phases are always shifted by 120 degrees with respect to the reference signal (in other words, having a predetermined phase with respect to the reference signal).

  When it is determined that switching to single-phase alternating current is instructed, the CPU 22a2 communicates with the CPUs 22b2 and 22c2 to output the V-phase and W-phase from 26b and 26c based on the output from the U-phase terminal 26a. Are controlled so as to match in phase, and single-phase alternating current is output from the single-phase output terminal 26f.

  That is, the CPU 22a2 generates a reference signal having a predetermined frequency, generates a synchronization signal having a predetermined phase (more precisely, the same phase) with respect to the reference signal, and transmits the synchronization signal to the CPUs 22b2 and 22c2. Based on the output from the terminal 26a, the operation of the inverter unit 22 is controlled so that the V-phase and W-phase outputs from 26b and 26c coincide in phase, and single-phase AC is output from the single-phase output terminal 26f.

  FIG. 10 is a waveform diagram showing switching from three-phase to single-phase output in this embodiment, and FIG. 11 is a waveform diagram showing switching in the opposite case. When the user operates the change-over switch 30e of the control panel unit 30, three-phase alternating current and single-phase alternating current with a desired voltage are selectively output as shown in the figure.

  Since the feature of the present invention is that a plurality of the inverter generators 10 are operated in parallel, this will be described below.

  12 is a perspective view of the inverter generator 10 showing a case where a plurality of the inverter generators 10 of FIG. 1 are operated in parallel, more specifically, two generators 10A and 10B. FIG. 13 is a diagram showing FIG. It is a block diagram which shows operation | movement of the control part of the inverter part 22 when carrying out the parallel operation of the two inverter generators 10A and 10B. In this embodiment, the generator 10A is a slave machine and the generator 10B is a master machine.

  The generator 10 </ b> A and the generator 10 </ b> B are connected by a dedicated connection cable 34 and also connected by an external communication line (CANBUS) 36. In addition, CPU22a2, 22b2, 22c2 of the inverter part 22 of 10 A of slave side generators functions as a parallel operation control apparatus of the generator in this Example.

  As shown in FIG. 13, the U, V, and W phase terminals 26a1, 26b1, and 26c1 of the terminal group 26d of the three-phase output terminal 26e of the generator 10A and the neutral points 26a2, 26b2, and 26c2 respectively connect the connection cable 34. Are connected to the U, V, W phase terminals 26a1, 26b1, 26c1 of the terminal group 26d of the corresponding three-phase output terminal 26e of the generator 10B and the neutral points 26a2, 26b2, 26c2, respectively, Single-phase AC outputs from the output terminals of the generators 10A and 10B are combined to form an output terminal (three-phase AC output terminal) 26e composed of U, V, and W phases. The output terminal 26e is supplied to the electric load 32 via the connection cable 34.

  Here, “arbitrarily connected” means that in this embodiment, the U-phase terminals 26a1, the V-phase terminals 26b1, and the W-phase terminals 26c1 may be connected as expected as shown. Alternatively, it means that the U-phase terminal 26a1 and the V-phase terminal 26b1, the V-phase terminal 26b1 and the W-phase terminal 26c1, and the W-phase terminal 26c1 and the U-phase terminal 26a1 may be connected by mistake.

  The single-phase AC output of each phase of U, V, and W synchronized for each corresponding inverter 22 between the generators 10A and 10B is sent from the three-phase AC output terminal 26e to the electric load 32 via the connection cable 34. Supplied.

  As illustrated, the neutral points 26a2, 26b2, and 26c2 of the generator 10A and the corresponding neutral points 26a2, 26b2, and 26c2 of the generator 10B are connected by the connection cable 34 and supplied to the electric load 32. That is, the generators 10A and 10B operated in parallel supply power to the electric load 32 as a three-phase four-wire inverter generator.

  Further, as shown in the figure, the generator 10A and the generator 10B, more specifically, the CPUs 22a2, 22b2, and 22c2 of the generator 10A and the generator 10B are connected by a CANBUS 36. During parallel operation, power generation on the master side, the generator 10B, and the slave side Information such as generated voltage and generated current is transmitted and received between the machines 10A. As a result, when the output of the master side generator 10B and the slave side generator 10A is smaller than that of the counterpart machine, the FETs such as the H bridge circuits 22a12, 22b12, 22c12 are turned on / off to control the voltage amplitude amount. The voltage phase amount is corrected to suppress unbalance current and cross current.

  FIG. 14 is a flowchart showing the operations of the first, second, and third control units 22a2, 22b2, and 22c2 of the inverter unit when the two generators 10A and 10B are operated in parallel.

  When parallel operation control of the generator 10A and the generator 10B is started, in S (step) 10, the first, second, and third inverters 22a, 22b, their own first, second, and third inverters 22a, 22b, The phase of the single-phase AC output of the first, second, and third inverters 22a, 22b, and 22c of the generator 10B that is input to 22c is discriminated, and the first, second, and third inverters 22a and 22b of its own. , 22c, an inverter to which U-phase alternating current is input is specified.

  Specifically, the CPU 22a2, CPU 22b2, and 22c2 of the generator 10A are respectively connected from the inverters 22a, 22b, and 22c of the generator 10B via the connection cable 34 based on the outputs of the phase voltage / phase current sensors 22a3, 22b3, and 22c3. The detected zero-cross timing of the U, V, and W-phase alternating current is detected, and is input to the first, second, and third inverters 22a, 22b, and 22c of the self (generator 10A) based on the detected zero-cross timing. The phase of the single-phase AC output of the first, second, and third inverters 22a, 22b, and 22c of the generator 10B is determined, and the U-phase of the first, second, and third inverters 22a, 22b, and 22c is determined. Specify the inverter to which AC is input.

  Next, the process proceeds to S12, and the outputs from the first, second, and third inverters 22a, 22b, and 22c are input via the connection cable 34 based on the detected zero cross timing and the determined phase. An output signal is generated that is synchronized with the output, phase, and output order from the first, second, and third inverters 22a, 22b, and 22c of the generator 10B.

  More specifically, a U-phase alternating current of the generator 10B is output based on any one of the outputs of the first, second, and third inverters 22a, 22b, and 22c of the generator 10A. Based on the output of the inverter connected to the inverter 22, it outputs the U-phase, and thereafter synchronizes with the U-phase, V-phase, and W-phase single-phase alternating current of the generator 10 </ b> B that is input, An output signal including the phases of the remaining two inverters and the output order (the operation order of the first, second, and third inverters 22a, 22b, and 22c) is generated.

  Next, the process proceeds to S14, and after starting the synchronous operation with the corresponding inverter of the generator 10B based on the inverter that outputs the U-phase alternating current based on the output signal generated in S12, the V-phase and W-phase alternating currents are similarly obtained. Parallel operation with the generator 10B is performed by communicating with the CPUs 22b2 and 22c2 and controlling on / off of these switching elements so that the output inverter is also synchronized with the single-phase AC output of the corresponding inverter of the generator 10B. Realize.

  FIG. 15 is a diagram showing output waveforms of the generator 10A and the generator 10B in this embodiment. In the figure, an alternating current waveform represented by a solid line represents an output from the first inverter 22a of the generators 10A and 10B, and an alternating current waveform represented by a broken line represents an output from the second inverter 22b of the generators 10A and 10B. Represents the output from the third inverter 22c of the generators 10A and 10B.

  In the illustrated example, the first inverter 22a of the generator 10B, the third inverter 22c of the generator 10A, the second inverter 22b of the generator 10B, and the first inverter 22a of the generator 10A are connected to the generator 10B. The state where the 3rd inverter 22c and the 2nd inverter 22b of the generator A were connected is represented.

  As shown in the figure, in this embodiment, regardless of how the output terminals of the generator 10A and the generator 10B are connected, the inverters 22a, 22b, 22c of the generator 10A are connected to each other. Synchronous operation of the output, phase, and output order of the first, second, and third inverters 22a, 22b, and 22c of the generator 10B (in the illustrated example, the output order of the generator 10A is 3, 1, and 2) is possible. Therefore, the generator 10A and the generator 10B can be reliably operated in parallel.

  Moreover, since the generator 10B on the master side performs the above-described independent operation control, and the three-phase alternating current output from the generator 10B is controlled by the CPU 22a2 (first control unit) of the generator 10B, The first, second, and third control units 22a2, 22b2, and 22c2 of the generator 10A on the slave side are connected to the inverters of the generator 10B to which the first, second, and third inverters 22a, 22b, and 22c correspond. The parallel operation with the three-phase AC output of the generators 10A and 10B can be reliably performed only by controlling the output and the phase so as to be synchronized.

  FIG. 16 is a flowchart for explaining the operation of the first, second, and third control units (CPUs 22a2, 22b2, and 22c2) of the generator 10A. The illustrated program is repeatedly executed at a predetermined cycle after the engine 12 of the generator 10A is started.

  Hereinafter, the CPU 22a2 (first control unit) of the generator 10A will be described as an example. However, since the configuration of each control unit is basically the same, the description of the CPU 22a2 is CPU 22b2, 22c2 (second and third control). Part).

  As shown in FIG. 16, the CPU 22a2 determines whether or not the generator 10B is in parallel operation in S100. Specifically, this is performed, for example, by determining whether or not the output of the first inverter 22a of the generator 10B is detected by the interphase voltage / interphase current detection sensor 22a3 via the connection cable 34.

  When the result in S100 is negative, the subsequent processing is skipped, while when the result is affirmative and it is determined that the generator 10B is in parallel operation, the process proceeds to S102, and the output of the self (the first inverter 22a of the generator 10A) is output. It is determined whether the current value INV_A and the output current value INV_B of the first inverter 22a of the generator 10B are the same or substantially the same.

  When the result in S102 is affirmative, the subsequent processing is skipped. When the result is negative, the process proceeds to S104, and it is determined whether or not its own output current value INV_A is smaller than the output current value INV_B of the generator 10B.

  When the result is affirmative in S104, the process proceeds to S106, and the ON / OFF of the FETs of the H bridge circuits 22a12, 22b12, and 22c12 is controlled to increase and correct the output current value INV_A. Proceeding to S108, the same control is executed by transmitting to the generator 10B, and the output current value INV_B of the generator 10B is increased and corrected.

  As described above, in the parallel operation control apparatus for the inverter generator 10 in this embodiment, the first, second, and third windings (output windings) wound around the power generation unit 16 driven by the engine 12. 18a, 18b, and 18c), and the alternating current output from the first, second, and third windings is connected to the switching elements (the SCRs of the mixed bridge circuits 22a11, 22b11, and 22c11 and the H bridge circuits 22a12, 22b12). , 22c12 FET), and the first, second, and third inverters 22a, 22b, and 22c that output DC power by performing DC / AC conversion, and the first, second, and third inverters 22a, 22b, and 22c. The first, second, and third control units (CPUs 22a2, 22b2, and 22c) that are connected to each other so as to be able to communicate with each other. ), A terminal group 26d that is connected to the first, second, and third inverters 22a, 22b, and 22c, respectively, and outputs the AC output as one of the U phase, the V phase, and the W phase, and the terminal group Output terminals (three-phase output terminal 26e, single-phase output terminal 26f) connected to the neutral terminal, respectively, and in parallel with at least one inverter generator B (10B) having the same configuration and three-phase AC output The inverter generator A (10A) is operable, and the first, second, and third control units (CPUs 22a, 22b2, and 22c2) are configured such that the terminal group 26d of the output terminal 26e is the generator B (10B). Are arbitrarily connected to the terminal groups of the output terminals via the connection cable 34, and are input from the generator B (10B) to the first, second, and third inverters 22a, 22b, and 22c. The phase of the single-phase alternating current is determined, and the single-phase alternating current output of the first, second, and third inverters 22a, 22b, and 22c is output with a predetermined phase and output based on any one of the determined single-phase alternating currents. Since the switching elements of the first, second, and third inverters 22a, 22b, and 22c are controlled so as to be in order, the terminal group 26d of the output terminal 26e is connected to the generator B (10B). Are arbitrarily connected to the terminal group 26d of the output terminal 26e, in other words, even when erroneously connected to the U-phase and V-phase terminals, the V-phase and W-phase terminals, the W-phase and U-phase terminals, etc. The phase of the output single-phase alternating current is determined, and any one of the determined single-phase alternating currents, for example, the input to the first inverter 22a is used as a reference for the first, second, and third inverters 22a, 22b, and 22c. Single-phase AC output is By controlling on / off of the switching elements of the first, second, and third inverters 22a, 22b, and 22c so as to be in order of power, three-phase alternating current is output regardless of how the output terminals are connected. A plurality of, for example, two inverter generators 10 can be operated in parallel.

  Further, as described with reference to FIG. 15, the interphase voltage and the interphase current input from the generator B (10B) to the first, second, and third inverters 22a, 22b, and 22c are detected and detected. It is also possible to control on / off of the switching elements of the first, second, and third inverters 22a, 22b, and 22c so as to synchronize with the interphase voltage and the correlation current, thereby unbalanced loads other than the three-phase load. Even in a load state where the output between phases is unbalanced, such as when power is supplied to a single-phase load, parallel operation can be realized independently without affecting the output of other phases. Increase in unbalance current and cross current with the other aircraft can be avoided reliably.

  The first, second, and third control units (CPUs 22b2 and 22c2) of the generator B (10B) are configured to output the second and third inverters 22b, 22b, Since the ON / OFF of the switching element is controlled so that the phase of the output of 22c becomes a target value, in addition to the above-described effects, in each of the first, second, and third inverters 22a, 22b, and 22c The voltage and phase of the output three-phase alternating current can be accurately matched.

  The first control unit (CPU 22a2) of the generator B (10B) generates a reference signal and generates a synchronization signal having a predetermined phase with respect to the reference signal to generate the second and third control units. (The CPUs 22b2 and 22c2), so that the first, second, and third control units use the outputs from the first inverter 22a that constitutes the master based on the reference signal and the synchronization signal as the second, Since the ON / OFF of the switching element is controlled so that the phase of the output of the third inverters 22b and 22c becomes a target value, in addition to the above effects, the first, second and third inverters 22a and 22b , 22c can be more precisely matched to the three-phase AC voltage and phase output.

  Further, the terminal groups 26a, 26b, and 26c of the first, second, and third inverters 22a, 22b, and 22c are each a single-phase two-wire composed of any one of the U-phase, V-phase, and W-phase and the neutral terminal 26d. Since the output terminal (three-phase output terminal 26e, single-phase output terminal 26f) is configured to be a three-phase four-wire system connected to the terminal group and the neutral terminal, respectively, In addition, a plurality of three-phase four-wire inverter generators 10 can be operated in parallel with a simple configuration.

  The first, second, and third control units (CPUs 22a2, 22b2, and 22c2) are configured so that outputs (output current values INV_A and INV_B) of the first, second, and third inverters 22a, 22b, and 22c are When the output is different from the corresponding outputs of the first, second, and third inverters 22a, 22b, and 22c of the generator B (10B), more specifically, at least one of the voltage amplitude amount and the voltage phase amount of the AC output. Is configured to control on / off of the switching elements of the first, second, and third inverters 22a, 22b, and 22c so as to correct both of them (S10 to S18). A plurality of generators 10 can be reliably operated in parallel.

  In the above description, the FET is used as the switching element of the inverter unit 22. However, the present invention is not limited to this, and an IGBT (insulated gate bipolar transistor) may be used.

  Although the generator 10A has been mainly described, since the generator 10B operated in parallel has the same configuration as the generator 10A, the same effect can be obtained even if the generators 10A and 10B are replaced. Needless to say.

  In the above embodiment, the case where the two generators 10A and 10B are controlled in parallel connection has been described as an example. However, the number of generators that are operated in parallel is not limited to two, and may be any number. In that sense, claim 1 is expressed as at least one generator.

  10, 10A, 10B Inverter generator, 12 engine (internal combustion engine), 14 battery, 16 power generation unit, 16a stator, 16b rotor, 18 output winding (main winding, winding), 18a first winding, 18b first 2 windings, 18c 3rd winding, 20 output winding (sub-winding), 22 inverter section, 22a first inverter, 22a1 power module, 22a2 CPU (first control section), 22a3 phase voltage / phase current sensor, 22b 2nd inverter, 22b1 power module, 22b2 CPU (2nd control part), 22b3 phase voltage / phase current sensor, 22c 3rd inverter, 22c1 power module, 22c2 CPU (3rd control part), 22a11, 22b11, 22c11 mixing Bridge circuit (its SCR (switching element)), 2a12, 22b12, 22c12 H bridge circuit (FET (switching element)), 22c3 phase voltage / phase current sensor, 24 filter unit (filter), 26 output unit, 26a U phase terminal, 26b V phase terminal, 26c W phase terminal , 26d O-phase terminal, 26e three-phase output terminal, 26f single-phase output terminal, 26g switching mechanism, 28 engine control unit, 28c CPU, 30 control panel unit, 30d KEY switch, 30e changeover switch, 32 load (electric load), 34 Connection cable, 36 CANBUS

Claims (6)

  A switching element is used to connect the alternating current output from the first, second, and third windings to the first, second, and third windings that are wound around the power generation unit that is driven by the engine. The first, second, and third inverters that convert direct current to alternating current and output alternating current power, and the switching elements of the first, second, and third inverters are controlled on and off, and can communicate with each other. Terminals connected to the connected first, second, and third control units and the first, second, and third inverters, respectively, and outputting the AC output as one of the U phase, V phase, and W phase An inverter generator A having an output terminal connected to a group and a neutral terminal of the terminal group, and capable of operating in parallel with at least one inverter generator B having the same configuration and a three-phase AC output, , The first, second and third control units When the terminal group of the output terminals is arbitrarily connected to the terminal group of the output terminal of the generator B via the connection cable, the single input from the generator B to the first, second, and third inverters. The phase of the alternating current is determined, and the single-phase alternating current output of the first, second, and third inverters is in a predetermined phase and output order based on any one of the determined single-phase alternating currents. A parallel operation control device for an inverter generator that controls on / off of switching elements of the first, second, and third inverters.   The first, second, and third control units include an interphase voltage / interphase current detection unit that detects an interphase voltage and an interphase current input from the generator B to the first, second, and third inverters, respectively. A parallel operation control device for an inverter generator, wherein on / off of the switching elements of the first, second and third inverters is controlled so as to be synchronized with the detected interphase voltage and interphase current.   The first, second, and third control units of the generator B perform the switching so that the output phase of the second and third inverters becomes a target value based on the output from the first inverter that constitutes the master. 2. The inverter generator parallel operation control device according to claim 1, wherein on / off of the elements is controlled.   The first control unit of the generator B generates a reference signal, generates a synchronization signal having a predetermined phase with respect to the reference signal, and transmits the synchronization signal to the second and third control units. The second and third control units are configured so that the output phase of the second and third inverters becomes a target value based on the output from the first inverter constituting the master based on the reference signal and the synchronization signal. The parallel operation control device for an inverter generator according to claim 2, wherein on / off of the switching element is controlled.   The terminal group of the first, second, and third inverters is a single-phase two-wire system including any one of the U-phase, V-phase, and W-phase and the neutral terminal, and the output terminal is connected to the terminal group. The parallel operation control device for an inverter generator according to any one of claims 1 to 3, wherein the parallel operation control device is a three-phase four-wire system connected to a neutral terminal.   The first, second, and third control units may be configured such that the outputs of the first, second, and third inverters are different from the corresponding outputs of the first, second, and third inverters of the generator B. 5. The on / off control of the switching elements of the first, second, and third inverters is controlled so as to correct at least one of a voltage amplitude amount and a voltage phase amount of the AC output. The parallel operation control apparatus of the inverter generator in any one of.