JP5839834B2 - Parallel operation controller for inverter generator - Google Patents

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.

  Inverter generators that can be operated in parallel are well known, and examples thereof include the technology described in Patent Document 1. In the technique described in Patent Document 1, a single-phase two-wire inverter generator enables parallel operation by matching the phase and voltage amplitude with the counterpart machine.

Japanese Patent No. 2996542

  As described above, in Patent Document 1, parallel operation is possible by matching the phase and voltage amplitude with the counterpart device that operates in parallel in the single-phase two-wire inverter generator, but outputs three-phase alternating current. In the case of the inverter generator, it is necessary to match the phase of the three-phase alternating current and the voltage amplitude, so that it is difficult to perform parallel operation with the technique described in Patent Document 1.

  Accordingly, an object of the present invention is to provide a parallel operation control device for an inverter generator that solves the above-described problems and enables parallel operation of a plurality of inverter generators that output three-phase alternating current.

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. Connected, the alternating current output from the first, second, and third windings is DC / AC converted using a switching element to output alternating current power, both of which can be configured as a master and the rest as slaves The first, second, and third inverters and the first, second, and second switching elements of the first, second, and third inverters are controlled to be turned on and off, and are connected to each other via CANBUS. , A third control unit, and a terminal group connected to the first, second, and third inverters to output the AC output as one of the U phase, V phase, and W phase, and the neutrality of the terminal group Output terminal connected to each terminal And an inverter generator A capable of operating in parallel with at least one inverter generator B having the same configuration with three-phase AC output, wherein the U-phase, V-phase, and W-phase terminals of the output terminals are the generator When connected to the U-phase, V-phase, and W-phase terminals of B via connection cables, the first, second, and third control units are connected to the first and second of the generator B via CANBUS. are connected to the third control unit, the generator said first of said generator a from B via the connecting cable, the second, the first of the generator B to be inputted to the third inverter, Further comprising an interphase voltage / interphase current detecting means for detecting an interphase voltage and an interphase current of the second and third inverters, respectively, the first, second and third control units start generating power from the generator B When the generator A starts generating power, the power generation The first A, the second, the first, second, phase voltage of the third inverter of the generator B detected by the phase voltage and phase current of the third inverter is the phase voltage, phase current detecting means It said generator the first a to synchronize the respective phases current, second, and as configured to control the on and off switching elements of the third inverter.

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

  In the inverter generator parallel operation control device according to claim 3, the first control unit of the generator B generates a reference signal and 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 device according to claim 4, a 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 device according to claim 5, 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 inverter generator parallel operation control device 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 is output from them. The alternating current is converted into direct current / alternating current by using a switching element to output alternating current power, and the first, second, and third inverters, and the first, second, and third inverters, each of which can constitute a master and the remainder are slaves. Controls on / off of switching elements of the three inverters, and is connected to the first, second and third control units connected to each other via CANBUS and the first, second and third inverters, respectively. And an output terminal connected to each of the neutral terminals and a terminal group that outputs an alternating current output as any of the U phase, V phase, and W phase, and at least one inverter power generation having the same configuration Machine B Inverter generator A capable of parallel operation with three-phase AC output, output terminal U phase, V phase, and W phase terminals connected to U phase, V phase, and W phase terminals of generator B via connection cables, respectively When connected, the first, second and third control units are connected to the first, second and third control units of the generator B via CANBUS, respectively , and from the generator B via a connection cable. The interphase voltage and interphase current of the first, second, and third inverters of the generator B that are input to the first, second, and third inverters of the generator A are detected, and the generator B starts power generation. When the power generation of the generator A is started later, the interphase voltage and interphase current of the first, second and third inverters of the generator A are detected in the first, second and third inverters of the generator B detected . first, second, third-in generator a to synchronize each interphase voltage and phase current Since the three-phase output is controlled independently in each phase in each of the first, second, and third inverters, the three-phase output is controlled. The voltage and phase of the alternating current can be easily matched, so that a plurality of inverter generators that output three-phase alternating current, for example, two, can be operated in parallel.

The first, second, and third control units are connected to the first, second, and third control units of the generator B via CANBUS, respectively, and the generator A is connected from the generator B via a connection cable. After detecting the interphase voltage and the interphase current of the first, second, and third inverters of the generator B input to the first, second, and third inverters of the generator, When starting the power generation of A, the phase voltage and phase current of the first, second and third inverters of the generator A are detected as the phase voltage of the first, second and third inverters of the generator B detected. first generator a to synchronize the respective phases current, second, Owing to this arrangement to control the on and off switching elements of the third inverter, first in other words, the second, each of the third inverter The three-phase AC output is controlled independently in Therefore, even in an unbalanced load state other than a three-phase load, for example, when supplying power to a single-phase load, even in a load state where the interphase output is unbalanced, the parallel operation can be performed independently without affecting the output of other phases. In addition, it is possible to reliably avoid an increase in unbalance current during parallel operation and a cross current with the other aircraft.

In the inverter generator parallel operation control apparatus according to claim 2, the first, second, and third control units of the generator B are configured such that the first inverter constitutes the master when the first inverter constitutes the master. Since the on / off of the switching element is controlled so that the phase of the output of the second and third inverters becomes the target value with reference to the output from the inverter, in addition to the above-described effects, the first, second, The three-phase AC voltage and phase output from each of the third inverters can be accurately matched.

  In the inverter generator parallel operation control device according to claim 3, the first control unit of the generator B generates a reference signal and 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 4, 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 apparatus according to claim 5, 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 similarly operated in parallel. It is a figure which shows an output waveform when carrying out parallel operation by the process of the flowchart of FIG. Similarly, it is a figure which shows an output waveform when carrying out a parallel operation by the process of the flowchart of FIG.

  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). Or inverter generator) 22a, 22b, 22c, an inverter unit 22 having three sets of inverters, and a filter unit having three sets of filters, first, second and third filters 24a, 24b, 24c. 24, 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. CPU22a2,22b2,22c2 are communicably connected to each other by the communication line 2 2 d.

  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 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. , Generating synchronization signals 1 and 2 (shown in FIG. 9) for synchronizing the phase of the output on the slave side to that of the master side (having a predetermined phase difference with respect to the reference signal), and transmitting them to the CPUs 22b2 and 22c2. A synchronization signal control unit 22a23 and a communication control unit 22a24 that controls transmission / reception (communication) of a synchronization signal generated via the communication line 22d.

  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 whose phases are always shifted by 120 degrees with respect to the reference signal (in other words, having a predetermined phase difference with respect to the reference signal) are generated and transmitted.

  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. The CPUs 22a2, 22b2, and 22c2 of the first, second, and third inverters 22a, 22b, and 22c of the generator 10A on the slave side function as a generator parallel operation control device in this embodiment.

As shown in FIG. 13, the U, V, and W phase terminals 26a1, 26b1, and 26c1 of the generator 10A and the neutral points 26a2, 26b2, and 26c2 are connected to the corresponding U and V of the generator 10B via the connection cable 34, respectively. Connected to the V and W phase terminals 26a1, 26b1, 26c1 and the neutral points 26a2, 26b2, 26c2, respectively, and the single phase AC outputs from the output terminals of the generators 10A, 10B are combined into U, V , W-phase output terminal (three-phase AC output terminal) 26e. Output terminal 26e is connected to an electrical load 32 through the connection cable 34.

  Specifically, in the generators 10A and 10B connected in parallel as shown in the figure, after the user starts one generator, for example, the engine 12 of the master generator 10B and starts power generation, the slave side When the engine 12 of the generator 10A is started and the generator 10A starts generating power, the U, V, and W-phase alternating currents output from the inverters 22a, 22b, and 22c of the generator 10B correspond to the generator 10A. The phase voltage / phase current sensors 22a3, 22b3, and 22c3 detect the CPU 22a2, 22b2, and 22c2 (first, second, and third control units) of the generator 10A. Based on the switching element of the corresponding inverter (the SCR and H bridge of the mixed bridge circuits 22a11, 22b11, 22c11). The FETs of the circuits 22a12, 22b12, and 22c12) are independently controlled to turn on and off independently, and the single-phase alternating currents output from the inverters 22a, 22b, and 22c are detected. The inverters 22a, 22b, and 22c of the generator 10B are detected. Parallel operation is performed so that the single-phase alternating current and voltage and phase output from the power supply are synchronized.

  That is, the CPUs 22a2, 22b2, and 22c2 of the generator 10A are output from the inverters 22a, 22b, and 22c of the generator 10B based on the outputs of the phase voltage and phase current sensors 22a3, 22b3, and 22c3 of the generator 10A, respectively. U, V output from the first, second and third inverters 22a, 22b, 22c of the corresponding self (generator 10A) based on the detected zero cross timing based on the detected zero cross timing. The switching elements such as the bridge circuits 22a12, 22b12, and 22c12 of the first, second, and third inverters 22a, 22b, and 22c are independently controlled to be synchronized with the W-phase AC.

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 controllers 22a2, 22b2, and 22c2 of the generator 10A on the slave side are connected to the generators 10B that correspond to the outputs of the first, second, and third inverters 22a, 22b, and 22c. The parallel operation with the three-phase AC output of the generators 10A and 10B can be ensured only by controlling so as to synchronize with the output and phase of the inverter.

  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 drawing, the generator 10A and the generator 10B, more particularly CPU22a2,22b2,22c2 generator 10B and the generator 10A are connected by CANBUS36, power generation of the generator 10B and the slave side of the master side at the time of parallel operation 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 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 that is operated in parallel 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. 14, the CPU 22a2 determines whether or not the generator 10B is in parallel operation in S (step) 10. 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 phase voltage / phase current sensor 22a3 via the connection cable 34.

  When the result in S10 is negative, the subsequent processing is skipped. On the other hand, when the result is affirmative and it is determined that the generator 10B is in parallel operation, the process proceeds to S12 and the output of the self (first inverter 22a of the generator 10A) 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 S12 is affirmative, the subsequent processing is skipped, while when the result is negative, the process proceeds to S14, 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.

  If the result in S14 is affirmative, the process proceeds to S16, 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 S18, the same control is executed by transmitting to the generator 10B to increase and correct the output current value INV_B of the generator 10B.

  FIGS. 15 and 16 are diagrams showing output waveforms when two generators 10A and 10B according to this embodiment are operated in parallel.

  In this embodiment, the waveforms drawn with solid lines in FIGS. 15 and 16 represent the voltage waveforms obtained by adding the outputs of the generators 10A and 10B in parallel operation, and the waveforms drawn with broken lines represent the combined current waveforms. 15 shows a case where the generators 10A and 10B are not connected to the electric load 32 (during no-load operation), and FIG. 16 shows that the generators 10A and 10B have an electric load 32, which has a resistance of 4 kW in this example. The case where it is in contact with the electrical load 32 (during load operation) is shown. From FIG. 15, it appears that a current flows through the load 32 even during no-load operation, but the current indicated by a broken line in FIG. 15 indicates a cross current flowing between the generators 10 </ b> A and 10 </ b> B.

  Also, as shown in FIG. 16, when the generators 10A and 10B are connected to the load 32, the combined output current from the generators 10A and 10B is supplied to the load 32. As shown, the inverters 22a, 22b, and 22c are controlled so that the output voltage in each phase is equal and the output current is equally distributed among the phases, that is, the load current is shared.

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 converted into switching elements (the SCRs of the mixed bridge circuits 22a11, 22b11, and 22c11 and the H bridge circuits 22a12, 22b12, and 22c12). The first, second, and third inverters 22a, 22b, and 22c that can constitute a master and the rest are slaves, and the first and second inverters 22a, 22b, and 22c. , Controls on / off of the switching elements of the second and third inverters 22a, 22b, 22c, and communicates with each other via the CANBUS 28a. The first, second and third control units (CPUs 22a2, 22b2 and 22c2) connected to the first and second and third inverters 22a, 22b and 22c are connected to the U-phase. And a terminal group 26d that outputs as either V phase or W phase and an output terminal (three-phase output terminal 26e, single-phase output terminal 26f) respectively connected to the neutral terminal of the terminal group. An inverter generator A (10A) capable of operating in parallel with at least one inverter generator B (10B) having a configuration and three-phase AC output, wherein the U-phase, V-phase, and W-phase terminals of the output terminals are the power generation units When connected to the U-phase, V-phase, and W-phase terminals of the machine B via the connection cable 34, the first, second, and third control units are connected to the first, The second and third control units Each is connected, the generator said first of said generator A from B through the connection cable 34, the second, the first of the generator B to be inputted to the third inverter, the second, 3 further includes phase voltage / phase current detection means (phase voltage / phase current sensor) 22a3, 22b3, 22c3 for detecting the phase voltage and phase current of the three inverters, and the first, second, and third control units are When the power generation of the power generator A is started after the power generation of the power generator B is started, the interphase voltage and the interphase current of the first, second, and third inverters of the generator A are detected as the interphase voltage / interphase current. Switching elements of the first, second and third inverters of the generator A so as to be synchronized with the interphase voltage and interphase current of the first, second and third inverters of the generator B detected by the means , respectively. On / off Since it is configured to control, the three-phase AC voltage and phase output by controlling the three-phase output independently in each phase in each of the first, second, and third inverters 22a, 22b, and 22c. Therefore, a plurality of, for example, two inverter generators 10 that output a three-phase alternating current can be operated in parallel.

The first, second, and third control units are connected to the first, second, and third control units of the generator B via the CANBUS when operated in parallel with the generator B, respectively. From (10B), the interphase voltage and interphase current input to the first, second, and third inverters 22a, 22b, and 22c are detected, respectively, and the first and second are synchronized with the detected interphase voltage and interphase current. 2. Since the switching elements of the third inverters 22a, 22b, and 22c are controlled to be turned on / off, in other words, the three-phase alternating current outputs are output from the first, second, and third inverters 22a, 22b, and 22c, respectively. Because it is configured to control the power supply independently, the output of other phases can be achieved even in an unbalanced load state other than a three-phase load, for example, in a load state where the interphase output is unbalanced, such as when power is supplied to a single-phase load. Affects Ku independent it is possible to realize a parallel operation, it is possible to reliably avoid lateral flow increased and destination machine unbalanced current during parallel operation.

In addition, the first, second, and third control units (CPUs 22b2 and 22c2) of the generator B are configured such that when the first inverter constitutes the master, the output from the first inverter 22a that constitutes the master is used as a reference. As described above, the on / off of the switching element is controlled so that the phase of the output of the second and third inverters 22b and 22c becomes a target value. The voltage and phase of the three-phase AC output from each of the three inverters 22a, 22b, and 22c can be accurately matched.

The first control unit (CPU 22a2) 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 generate the second and third control units (CPU 22b2, CPU 22b2). 22c2), so that the first, second and third control units are based on the output from the first inverter 22a constituting the master based on the reference signal and the synchronization signal. Since the ON / OFF of the switching element is controlled so that the phase of the output of 22b, 22c becomes a target value, in addition to the above effect, the first, second, third inverters 22a, 22b, 22c The voltage and phase of the three-phase alternating current output in each can be matched more accurately.

  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 (5)

The AC output from the first, second, and third windings is connected to the first, second, and third windings wound around the power generation unit that is driven by the engine. / AC conversion and AC power is output, and the first, second, and third inverters that can both constitute a master and the rest can constitute a slave, and the switching elements of the first, second, and third inverters are turned on. The first, second, and third control units that are controlled to be turned off and connected to each other via CANBUS, and the first, second, and third inverters, respectively, and the AC output At least one inverter generator B having the same configuration, and a terminal group that outputs the U as a U-phase, V-phase, or W-phase, and an output terminal connected to the neutral terminal of the terminal group, Parallel operation with three-phase AC output Inverter generator A, when the U-phase, V-phase, and W-phase terminals of the output terminal are connected to the U-phase, V-phase, and W-phase terminals of the generator B via connection cables, respectively, first, second, third control unit, the first of the generator B via the CANBUS, second, is connected to the third control unit, the power from the generator B via the connecting cable Interphase voltage / interphase current detection means for detecting the interphase voltage and interphase current of the first, second, and third inverters of the generator B input to the first, second, and third inverters of the machine A The first, second, and third control units may further include the first, second, and third control units of the generator A when starting the power generation of the generator A after starting the power generation of the generator B. The interphase voltage and interphase current of the third inverter are the interphase voltage and interphase current detecting means. The first more detected said generator B, the second, the first of the generator A to synchronize each interphase voltage and phase current of the third inverter, the second switching elements of the third inverter An inverter generator parallel operation control device characterized by controlling on / off.   When the first inverter constitutes the master, the first, second, and third control units of the generator B are configured so that the second and third inverters are based on an output from the first inverter that constitutes the master. The inverter generator parallel operation control device according to claim 1, wherein on / off of the switching element is controlled so that a phase of the output of the inverter becomes a target value.   The first control unit of the generator B generates the 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 first, second, and third control units are configured such 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 based on the reference signal and the synchronization signal. 3. The inverter generator parallel operation control device according to claim 2, wherein the switching element is turned on and off.   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.