JP2013106447A - Method of controlling engine-driven inverter generator, and engine-driven inverter generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine-driven inverter generator that singly accommodates a wide range from a light load to a heavy load with fuel economy.SOLUTION: A generator 1 includes: input means 7 for inputting various settings and operational instructions for the generator; means for detecting a load side change; and a controller 8 for controlling the speed of an engine 21 on the basis of the input from the input means 7 and the detected load status. The input means 7 includes connected load setting means 74 for setting a size of load connected to the generator 1. The controller 8 is configured to execute, after starting the engine 21, a load startup mode of controlling the speed of the engine 21 at least to a load startup speed depending on the size of load set through the connected load setting means 74 in preparation for a load startup. When a load is started up, the engine is thus driven at the speed depending on the size of the connected load.

Description

  TECHNICAL FIELD The present invention relates to an engine-driven inverter generator control method and an engine-driven inverter generator, and more particularly, an engine control method mounted on an engine-driven inverter generator and an engine that executes the control method. The present invention relates to a drive type inverter generator.

  Engine-driven generators that generate power by driving the generator body with an engine are widely used as emergency power supplies in the event of a power failure, and in particular, components such as the engine and generator body are housed in a package. Package-type engine-driven generators are widely used because of their portability, such as in construction sites and event venues where it is necessary to secure power supplies outdoors.

  In such an engine-driven generator, when the AC generated in the generator body is output as it is, the frequency of the AC output from the generator body is determined by the rotational speed of the generator body. Therefore, it is necessary to perform “constant speed control” for maintaining the generator main body, and hence the engine speed at a constant speed.

  However, the generator itself in an operation state with a constant rotation speed shows a “drooping characteristic” in which the output voltage decreases as the load current increases and the output voltage increases as the load current decreases. When an engine-driven generator that is controlled in this way is connected to a load that consumes less power than the rated output power of the generator, the output voltage increases as the load current decreases. Thus, the amount of electric power supplied to the magnitude of the connected load becomes excessive by this voltage increase, and the engine consumes useless fuel.

  Therefore, without supplying the AC output from the generator itself to the load as it is, it is first converted to DC through a DC output section composed of diodes, etc., and then converted to AC at the desired frequency with an inverter. As a result, the frequency of the power supplied to the load is not determined by the rotational speed of the generator body, and the output voltage from the DC output unit is constant regardless of the size of the connected load. An engine-driven inverter generator that performs “constant voltage control” for controlling the rotational speed of the engine has been proposed (prior art of Patent Document 1).

  In other words, when such an engine-driven inverter generator is connected to a load that consumes less power than the rated output power of the generator, the output voltage of the DC output unit is reduced by the amount of power consumed by the load. Although the engine speed is controlled so that the output voltage of the DC output unit becomes constant by the constant voltage control described above, the engine speed can be reduced, and as a result, the load The fuel consumed by the engine can be reduced according to the decrease.

  In particular, in such an engine-driven inverter generator, a device equipped with a three-phase AC motor (hereinafter referred to as “motor load”) that requires a starting current several times the rated current is used. When the motor load is started and the load current is reduced when the motor load is shifted to the rated operation, the engine speed can be reduced correspondingly, and economical operation can be performed.

  It should be noted that in an engine-driven inverter generator that performs such constant voltage control, since the generator body is hardly loaded before starting the inverter after starting the engine, the DC output section of the generator is in this state. If the above-mentioned “constant voltage control” is performed so that the output voltage is constant, the rotation speed of the generator is reduced so that the voltage required to output the rated voltage from the inverter is reduced. When the inverter is started in this state without having reached the generated rotation speed, the inverter cannot output the rated voltage and the drive of the load may fail, and the load is connected to the inverter. When the inverter is started and the load is energized at the same time as the start-up, the load torque suddenly increases with the sudden increase in load current. In view of the possibility of stopping, the constant voltage control described above is not performed immediately after the engine is started, and the engine speed is set to the set speed, specifically, “the inverter is connected with the rated load connected to the inverter. The engine speed is set by operating in the constant speed control mode in which the output voltage is kept high enough to maintain a desired value (Patent Document 1 [0065] column). The inverter is started after the rotational speed is reached, and then, when a predetermined control mode transition condition such as a fixed time elapses after the start of the constant speed control mode, the above constant voltage control is performed. A control method has also been proposed (see Patent Document 1: Claims 1, 2, [0065] column).

JP 2005-137164 A

  In the engine-driven inverter generator described in Patent Document 1, the engine is operated in the constant speed control mode in which the engine is operated at the set rotational speed without performing constant voltage control until the control mode transition condition is satisfied after the engine is started. Since the inverter is started during operation in this constant speed control mode, the inverter can output the rated voltage immediately after startup, and the rated load (the maximum load that can be connected) is temporarily connected to the inverter. In addition, even when the energization of the load is started at the same time as the inverter is started, it is possible to suitably prevent output voltage shortage, load drive failure associated with this, engine stop due to increased load torque, etc. It has become something that can be done.

  However, in the constant speed control mode in Patent Document 1, in order to reliably prevent engine stop and load drive failure, connect the set rotational speed in the constant speed mode and the rated load (maximum load that can be connected). In such a state, it is necessary to set the rotation speed sufficiently high so that the output voltage of the inverter can be maintained at a desired value (Patent Document 1 [0065] column), that is, the rotation speed at which the inverter outputs the rated output power. is there.

  Therefore, in a conventional engine-driven inverter generator, the set rotational speed in the constant speed control mode is constant regardless of the size of the load that is actually connected. On the other hand, when a small load is connected and used, the rotational speed of the engine in the constant speed control mode becomes excessive with respect to the connected load, and therefore, wasteful fuel consumption is still performed.

  In the constant voltage control performed after the operation in the constant speed control mode, the rotational speed is controlled by adjusting the fuel injection amount of the engine in accordance with the output voltage of the DC output unit. If the change in voltage is rapid, there will be a slight delay in the change in engine speed.

  For this reason, if the engine speed is reduced to the minimum necessary in constant voltage control, if there is a sudden increase in load current due to additional connection of the load, etc., the sudden increase in load torque will cause the engine speed to increase. There is a risk that the engine will stop without catching up.

  Even if the engine can be stopped due to a sudden increase in load torque, the output voltage temporarily decreases while waiting for the engine speed to increase. There is also a risk of stopping the load.

  In particular, when the load to be additionally connected is a motor load that requires a large starting current, the increase in the load current due to the additional connection of the load becomes large, and the aforementioned engine stop and output voltage drop are likely to occur.

  For this reason, if it is to be surely prevented that the engine is stopped or the operating load is stopped, the engine rotation speed in constant voltage control is the engine required to supply the load side power consumption at that time. In addition, it is necessary to determine the rotation speed that can generate an output that adds an output margin that can correspond to the load fluctuation that can occur, and as the connected load becomes smaller than the rated load, Since the range of load fluctuation that can occur is also large, it is necessary to increase this margin.

  For this reason, even when the above-described constant voltage control is performed, useless fuel is still consumed for the above-described margin, and in particular, the load connected to the rated output power of the engine-driven inverter generator As the power consumption decreases, wasteful fuel consumption increases.

  In this way, in the conventional engine-driven inverter generator, if the engine is stopped or the load is stopped due to a drop in output voltage, the rated output power of the generator is used as a reference. Regardless of the size of the load actually connected, it is assumed that the rated load is connected or the load reaches the rated load in either the constant speed operation mode or constant voltage control. Therefore, it is necessary to drive the engine at a rotational speed with a sufficient margin to cope with this.

For this reason, it is possible to connect a heavy load generator to a light load, but use in such a state significantly deteriorates fuel consumption. If you want to generate power that is fuel-efficient and environmentally friendly with reduced CO ₂ emissions and noise, you can use rated output power such as “for heavy load”, “for standard”, “for light load”, etc. It is necessary to separately prepare multiple generators with different rated power and select and use a generator with the rated output power corresponding to the load to be used according to the application. It was necessary to invest a great amount of initial investment.

Therefore, development of an engine-driven inverter generator that can handle light loads to heavy loads while suppressing wasteful fuel consumption, unnecessary CO ₂ emissions, and noise generation with a single generator is desired. It had been.

Therefore, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and it is possible to deal with a wide range from a light load to a heavy load in a single engine-driven inverter generator. When connected with a load, the fuel efficiency and low fuel consumption are equivalent to or better than those of the conventional engine-driven inverter generators designed exclusively for “light load”, “standard” and “heavy load”. An object of the present invention is to provide an engine-driven inverter generator capable of realizing CO ₂ emission and low noise, and a control method thereof.

  Hereinafter, means for solving the problem will be described together with reference numerals used in the embodiment for carrying out the invention. This code is used to clarify the correspondence between the description of the scope of claims and the description of the mode for carrying out the invention. Needless to say, it is used in a limited manner for the interpretation of the technical scope of the present invention. It is not a thing.

In order to achieve the above object, an engine-driven inverter generator control method according to the present invention includes an engine 21, a generator main body 22 driven by the engine 21, and alternating current generated in the generator main body 22 converted into direct current. And an inverter 32 that converts the direct current output from the converter 31 into a predetermined alternating current and supplies the converted alternating current to a load, and the rotational speed of the engine 21 is variable depending on the load condition In generator 1,
A connection load setting means 74 for setting the magnitude of a load connected to the engine-driven inverter generator 1 is provided, and a predetermined load corresponding to the magnitude of the load set by the connection load setting means after the engine is started. A load start mode for operating the engine at a speed higher than the start rotational speed is performed, and after the start of the load in the load start mode is detected, the load start mode is ended, and the engine 21 is determined according to the load condition. It shifts to the normal operation mode which drive | operates with the rotational speed of (Claim 1).

In the load start mode in the control method of the engine drive type inverter generator 1 described above, the load state connected to the engine drive type inverter generator 1 is detected as the load size, and the detected load size and When the detected load magnitude is larger than the set load magnitude by comparing the set load magnitude, the previously stored load magnitude and the rotation speed of the engine 21 are compared. Based on the correspondence, the logical rotational speed of the engine 21 is obtained from the detected load magnitude, the logical rotational speed is set as the target rotational speed, and the detected load magnitude is the set load magnitude. If the load starting rotational speed is the target rotational speed, the target rotational speed is compared with the actual rotational speed of the engine 21 to obtain the target rotational speed. It is controlled engine 21 so that the degree and the measured rotational speed is in good agreement (claim 2), or,
In the load start mode in the control method of the engine-driven inverter generator 1 described above, the state of the load connected to the engine-driven inverter generator 1 is detected, and the load state stored in advance and the rotational speed of the engine 21 are detected. The logical rotation speed of the engine 21 is obtained from the detected load condition, and the load starting rotation speed is compared with the logical rotation speed obtained based on the load condition, so that the logical rotation When the speed is higher than the load starting rotational speed, the logical rotational speed is set as a target rotational speed. When the logical rotational speed is equal to or lower than the load starting rotational speed, the load starting rotational speed is set as the target rotational speed. The target rotational speed is compared with the actual rotational speed of the engine 21, and the engine 21 is controlled so that the target rotational speed and the actual rotational speed coincide with each other. It is also possible (claim 3).

  Further, in the load starting mode in the control method of the engine-driven inverter generator 1 described above, the state of the load connected to the engine-driven inverter generator is obtained as a value indicating the magnitude of the load, The activation of the load can also be detected when the value indicating the magnitude is maintained at a predetermined value higher than 0 continuously for a preset time.

The load status may be detected by the power consumption of the load connected to the engine-driven inverter generator 1 (Claim 5), or
You may make it detect the condition of the said load from the electric current value of the load connected to the said engine drive type inverter generator 1 (Claim 6).

Further, the engine-driven inverter generator 1 of the present invention that implements the above control method includes an engine 21, a generator main body 22 driven by the engine 21, and a converter that converts alternating current generated in the generator main body 22 into direct current. 31 and an inverter 32 that converts a direct current output from the converter 31 into a predetermined alternating current and supplies the converted alternating current to a load, and an engine-driven inverter generator in which the rotational speed of the engine 21 is variable according to the load condition In 1,
Input means 7 for inputting various settings and / or operation instructions for the engine-driven inverter generator 1, load condition detecting means for detecting the condition of a load connected to the engine-driven inverter generator; A controller 8 is provided for controlling the operation of the engine 21, inverter 32 and converter 31 based on various settings and operation instructions input via the input means 7 and the load conditions detected by the load condition detecting means. In addition, the input means 7 includes connection load setting means for setting the magnitude of the load connected to the engine-driven inverter generator, and the controller is set by the connection load setting means after the engine is started. The engine is operated at a speed equal to or higher than a predetermined load starting rotational speed corresponding to the magnitude of the load prepared to prepare for starting the load. After executing the load starting mode and determining that the load has been started based on the load state detected by the load state detecting means, the load starting mode is ended, and the engine is turned on according to the load state according to the load state. It is configured to shift to a normal operation mode that operates at a rotational speed (claim 7).

The controller 8 of the engine-driven inverter generator 1 having the above configuration is compared with the load size in the detected load state and the set load size, and the detected load size is set to the set value. If the magnitude of the load is larger than the detected load magnitude, the logical rotation speed of the engine is obtained from the detected magnitude of the load based on the correspondence relationship between the magnitude of the load stored in advance and the rotation speed of the engine 21. If the logical rotational speed is the target rotational speed and the detected load is less than or equal to the set load, the load starting rotational speed is the target rotational speed and the target rotational speed and the engine 21 are set. May be provided with a function of controlling the engine 21 so that the target rotational speed and the measured rotational speed coincide with each other (Claim 8), or
Based on the correspondence relationship between the load condition stored in advance and the rotation speed of the engine 21, the logical rotation speed of the engine 21 is obtained from the detected load condition. If the logical rotation speed is higher than the minimum rotation speed by comparing the load starting rotation speed and the logical rotation speed obtained based on the load condition, the logical rotation speed is set to the target rotation speed. When the logical rotational speed is equal to or lower than the minimum rotational speed, the target rotational speed is compared with the actual rotational speed of the engine 21 with the minimum rotational speed as the target rotational speed, and the target rotational speed and the actual rotational speed are compared. May be provided with a function of controlling the engine 21 so that the two coincide with each other.

In the engine-driven inverter generator 1 configured as described above, the controller 8 includes:
When in the load start mode, the load status detected by the load status detection means is received as a detection signal;
From the received detection signal, obtain a value indicating the magnitude of the detected load and the duration of the value,
It may be configured to determine that the load has been activated when the acquired value is continuously maintained for a preset time for a preset time, which is equal to or higher than a predetermined value (Claim 10).

The load status detection means may detect the power consumption of the load connected to the engine-driven inverter generator 1 as the load status (claim 11), or
The load status detection means may detect a current value of a load connected to the engine-driven inverter generator 1 as the load status (claim 12).

  With the configuration of the present invention described above, according to the engine-driven inverter generator 1 of the present invention, the following remarkable effects can be obtained.

  After the engine 21 is started, a load start mode in which the engine 21 is operated at a predetermined load start rotation speed corresponding to the magnitude of the load set by the connection load setting means 74 is performed. As a result, the engine speed in the load startup mode was able to be optimized for the size of the connected load.

As a result, it is ensured that the engine 21 will be stopped and the output voltage will be greatly reduced regardless of whether heavy load or light load is connected to one engine-driven inverter generator 1. In addition, it was possible to generate power with fuel consumption, CO ₂ emissions, and noise generation according to the size of the connected load.

  When the actual load in the load starting mode is larger than the preset load size from the detected load state, the engine 21 is controlled with the logical rotation speed corresponding to the load condition as the target rotation speed. By doing so, even if the power consumption of the connected load exceeds the power consumption assumed in advance, this difference is corrected, and the engine 21 is stopped and the output voltage is reduced. Can be prevented.

  Further, the logical rotational speed is obtained from the load state in the load starting mode, and when the logical rotational speed is higher than the load starting rotational speed corresponding to the magnitude of the load, the engine 21 is operated with the logical rotational speed as the target rotational speed. As a result of the control, even if the power consumption of the connected load exceeds the power consumption assumed in advance, this difference is corrected, causing the engine 21 to stop and the output voltage to drop. This can be prevented.

  Further, when in the load starting mode, when the measured value indicating the load state continues for a set time and maintains a predetermined value higher than 0, it is determined that the load has been started, and the engine 21 is operated at high speed. The useless fuel consumption can be suppressed by ending the additional load starting mode and automatically returning to the normal operation mode in which the engine 21 is operated according to the load condition.

  When the load power consumption is detected as the load status, the engine can be operated at an appropriate rotational speed according to the load power consumption. For example, the power factor is increased by a sudden load fluctuation such as a motor load. Even if reactive power increases or decreases, the rotational speed of the engine 21 is changed based on the power consumption. Therefore, the rotational speed of the engine 21 does not fluctuate unnecessarily, and the engine 21 is operated at a stable rotational speed. Since it can be operated, the fuel consumption can be reduced and the noise can be reduced.

  Alternatively, when the load current value is detected as the load state, the load state is simpler than the structure for detecting the load state based on power consumption, and does not require a complicated program. Since the change of the engine speed can be detected quickly, the engine 21 can be prevented from being stopped and the output voltage can be significantly reduced due to the control delay.

The block diagram which shows the structural example of the engine drive type inverter generator of this application. Explanatory drawing which shows the structural example of an input means. FIG. 3 is a correlation diagram of engine rotation speed and connectable load. Flow before transition to load startup mode in engine-driven inverter generator. The flow of the load starting mode in an engine drive type inverter generator. Flow of normal operation mode in an engine-driven inverter generator. The flow of another normal operation mode in an engine drive type inverter generator. Flow of additional load startup mode in engine-driven inverter generator.

  Hereinafter, an engine-driven inverter generator of the present invention and a control method performed in the engine-driven inverter generator will be described with reference to the accompanying drawings.

[Configuration of generator]
(1) Overall Configuration In FIG. 1, reference numeral 1 denotes an engine-driven inverter generator according to the present invention. The engine-driven inverter generator 1 includes an engine 21 and a generator main body 22 driven by the engine 21. A power converter 2 having a converter 31 for converting the alternating current generated in the power generator 2 into a direct current, and an inverter 32 for converting the direct current from the converter 31 into an alternating current of a predetermined frequency and outputting it. A waveform shaping unit 4 having filters 41 to 43 for improving the output waveform of the conversion unit 3 is provided, and an AC output shaped by the waveform shaping unit 4 is output from an output terminal block 6 connected via a breaker 5 or the like. It can be taken out.

  The engine-driven inverter generator 1 includes an input unit 7 for inputting various settings and operation instructions by a user, and various settings and operation instructions input via the input unit 7. A controller 8 is provided for controlling the operation of the power generation unit 2 and the power conversion unit 3 based on detection signals from 3 and the like.

(2) Power Generation Unit The power generation unit 2 includes an engine 21, a generator main body 22 driven by the engine, and an engine control unit (ECU) 26 that controls the rotational speed of the engine. The rotating shaft of the generator main body 22 is connected, and the engine 21 and the generator main body 22 rotate in synchronization.

  In this embodiment, the generator body 22 is a permanent magnet generator, and is driven by the engine 21 described above to generate and output a three-phase alternating current having a frequency corresponding to the rotational speed.

  The engine 21 is provided with an electronic governor 24 that adjusts the amount of fuel injected into the combustion chamber by an electrical signal, and a rotational speed sensor 25 that detects the rotational speed.

  The engine control unit (ECU) 26 is an electronic control device for comprehensively performing electrical control of the engine 21, and by transmitting a control signal to the electronic governor 24 provided in the engine 21, The injection amount, the injection timing, etc. can be controlled, and the deviation between the rotational speed (measured rotational speed) detected by the rotational speed sensor 25 of the engine 21 and the rotational speed (target rotational speed) output from the controller 8. A fuel control signal for instructing the fuel injection amount (or fuel increase / decrease amount) is transmitted to the electronic governor 24 so that becomes zero.

  In the present embodiment, the rotational speed sensor 25 transmits a rotational pulse signal at every predetermined rotational angle of the engine 21, and the ECU 26 calculates an actual rotational speed based on the rotational pulse signal.

(3) Power Conversion Unit The power conversion unit 3 includes a converter 31 that converts the three-phase alternating current output from the generator body 22 into direct current, and an inverter that converts the direct current output from the converter 31 into a predetermined three-phase alternating current. 32, a control unit 33 for controlling the converter 31 and the inverter 32, a current detection means 34 for detecting a current value of the three-phase AC input to the converter, and a current value of the three-phase AC output from the inverter Current detecting means 35 for performing the operation.

  The three-phase alternating current output from the generator main body 22 is input to a converter 31 provided in the power conversion unit 3 and rectified to direct current by switching a plurality of transistors built in the converter 31, and then the capacitor Is smoothed and output.

  In the present embodiment, the converter 31 is provided with a booster circuit (not shown) that outputs a predetermined DC voltage value higher than the input three-phase AC voltage value, and the capacitor is used for smoothing and load variation. Therefore, the DC voltage value can be stabilized by the action of the booster circuit and the capacitor.

  The direct current converted from the three-phase alternating current by the converter 31 is then input to the inverter 32 also provided in the power conversion unit 3, and the frequency set by the user by the input means 7 and the output set by the user separately. A plurality of transistors built in the inverter 32 are switched so as to have a voltage value, converted into a three-phase alternating current by a PWM (pulse width modulation) method, and output.

  The converter 31 and the inverter 32 are controlled by a control unit 33 which is an electronic control unit. The control unit 33 includes a current value of each phase of the three-phase AC input to the converter 31 detected by the current detection means 34, a converter The DC voltage value between the inverter 31 and the inverter 32, the current value of each phase of the three-phase AC output from the inverter detected by the current detecting means 35, and the rotational speed sensor 25 for each predetermined rotation angle of the engine 21 are input. A rotation pulse signal transmitted from the controller 8, a frequency and output voltage command signal transmitted from the controller 8, and the like are received.

  The control unit 33 estimates the electrical angle of the generator body 22 from the rotation pulse signal, and then converts the current value of each phase of the three-phase AC input to the converter 31 into a q-axis current value and a d-axis current value. An electrical angle is obtained based on the q-axis current value and the d-axis current value, the estimated electrical angle is replaced with the electrical angle, a PWM signal is generated based on the electrical angle, and the generated PWM signal is sent to the converter 31. Output to each of the built-in transistors. Furthermore, an electrical angle is generated based on the frequency command signal output from the controller 8, and based on the generated electrical angle, the output voltage command signal output from the controller 8, and the DC voltage value between the converter 31 and the inverter 32. The PWM signal is generated, and the generated PWM signal is transmitted to each of the plurality of transistors built in the inverter 32.

  In addition, the control unit 33 converts the current value of each phase of the three-phase AC output from the inverter 32 from an electrical angle generated based on the frequency command signal into a q-axis current value and a d-axis current value. The power consumption on the load side is calculated from the current value and the d-axis current value, the command signal of the output voltage transmitted from the controller 8, and the load connected to the engine-driven inverter generator 1 by this power consumption. The situation is detected and the power consumption is output to the controller 8.

  In this embodiment, the load status detection means is a device that transmits various settings, signals, commands, and the like for calculating the power consumption, in addition to the control unit 33 for calculating the power consumption. The controller 8 and the ECU 26 are included.

  The load status detection means is not limited to the present embodiment, and is a current detection means 35 for detecting the current value of the three-phase AC output from the inverter 32, and the load status is detected based on this current value. Also good.

  The rotation pulse signal transmitted from the rotation speed sensor 25 of the engine 21 may generate the rotation speed (measured rotation speed) of the engine by the control unit 33 and output it to the controller 8.

(4) Waveform shaping unit The three-phase alternating current having a predetermined frequency output from the power conversion unit 3 is then subjected to waveform shaping via the waveform shaping unit 4 and output to a load connected to the output terminal block 6. Is done.

  In the present embodiment, the waveform shaping unit 4 is constituted by an LC filter constituted by an AC reactor 41 and a filter capacitor 42 and a common mode choke 43, and the inverter 32 is constituted by the LC filter (41, 42). In addition to improving the output current / voltage waveform, the harmonics and high frequencies are removed to make the three-phase alternating current close to a sine wave, and the common mode choke 43 removes common mode noise.

(5) Input means
(5-1) Outline The input means 7 is a means for the user to input various settings and commands for the engine-driven inverter generator 1. For example, momentary switches such as button switches, changeover switches and volume switches (variable resistance It may be configured by mechanical switches such as a display device, and all or part of the input means is realized by a liquid crystal screen having a touch panel function. The various settings described above may be input by touching a predetermined position. Various settings and commands input by the user via the input means 7 are transmitted to the controller 8.

  In the embodiment shown in FIG. 2, the input means 7 further includes a frequency setting means 71, an output voltage setting means 72, an additional load start mode start command input means 73, a connection load setting means 74, a minimum rotation speed setting means 75, and A starter switch 76 is provided.

(5-2) Frequency setting means The frequency setting means 71 is a means for setting the frequency of the three-phase AC output from the output terminal block 6 of the engine-driven inverter generator 1 of the present invention, as shown in FIG. In the embodiment, as the frequency setting means 71, a frequency adjustment volume 711 and a frequency changeover switch 712 are further provided so that the frequency adjustment volume 711 can set the frequency to an arbitrary value and the output frequency. Is set to a commercial frequency (50 Hz or 60 Hz) in Japan, the frequency can be selected and set by switching the frequency switch 712.

(5-3) Output voltage setting means The above-mentioned output voltage setting means 72 is a means for setting the output voltage. In the illustrated embodiment, the output voltage setting means 72 further includes an output voltage. An adjustment volume 721 and an output voltage changeover switch 722 are provided so that the output voltage can be set to an arbitrary value by the output voltage adjustment volume 721, and the load side rated voltage is generally set to 200V or 220V. In this case, one of the output voltages can be selected and set by switching the output voltage selector switch 722.

(5-4) Additional load start mode start command input means The additional load start mode start command input means 73 is used in the normal operation mode when starting an additional load during operation in the normal operation mode, as will be described later. In this embodiment, this switch is provided as a switch for ON / OFF switching.

  Of course, the additional load starting mode start command input means 73 is, for example, an additional load starting rotational speed that is the rotational speed of the engine in the additional load starting mode, which will be described later, according to the total of the load already driven and the load to be additionally connected. It may be configured as a volume switch for setting the value, a changeover switch for selecting from a preset rotation speed, or it may be configured with a momentary switch, and the momentary switch is operated to shift to the additional load starting mode. Alternatively, the additional load starting rotational speed may be increased or decreased by a predetermined rotational speed for each operation of the momentary switch.

  In addition, means for inputting a command to shift to the additional load starting mode and means for setting the additional load starting rotational speed may be provided separately.

(5-5) Connected load setting means The connected load setting means 74 is a means for setting the magnitude of the load to be started first after the engine is started. In this embodiment, the magnitude of the load to be connected is set. Three types are set: light load (motor load with a rating of 7.5 kW or less), standard (motor load with a rating of 11 kW or less), and heavy load (motor load with a rating of 15 kW or less). Although it is configured as a changeover switch to be selected, a momentary switch that can change the setting step by step according to the number of operations is provided in place of or along with this configuration, or the load to be connected is large It is also possible to provide a volume switch that can be set steplessly and to set the magnitude of the load to be connected stepwise or arbitrarily.

(5-6) Minimum rotation speed setting means The minimum rotation speed setting means 75 is for setting the minimum rotation speed of the engine 21 in the normal operation mode described later. In the illustrated embodiment, this is switched. One of auto (minimum rotation speed 1300 min ^-1 ) and power (minimum rotation speed 2200 min ^-1 ) can be selected and set as a switch.

  Of course, as this minimum rotation speed setting means 75, a volume switch for setting the above-mentioned minimum rotation speed to an arbitrary value is provided together with or instead of the above-mentioned changeover switch, and the minimum rotation speed can be arbitrarily set. It is also good.

(5-7) Starter switch The starter switch 76 is a start / stop switch for the engine-driven inverter generator 1. By operating the starter switch 76, the engine 21, the controller 8, the input means 7, and other electrical components are provided. The “stop” position where the power supply to the engine 21 is cut off, the “run” position where the power supply to the engine 21 and the electrical components are started and the engine 21 can be operated, and the cell motor (not shown) provided in the engine 21 is supplied with power. The switch can be switched between “start” positions at which the engine 21 is started. In this embodiment, the starter switch can be switched between the positions by inserting a key. Using a switch that enables

  In the illustrated embodiment, a single switch can be used to switch between the three positions of stop, operation, and start. For example, a switch that switches between the “stop” and “run” positions (for example, a switch) A switch) and a switch (for example, a momentary switch) for starting the cell motor may be provided separately.

(6) Controller Various settings and commands input by the user via the input means 7 described above, the power consumption on the load side output from the control unit 33, the rotational speed of the engine 21, and the waveform shaping unit 4 The line voltage values between the three-phase alternating current phases are all input to the controller 8 constituted by a microcontroller or the like.

  The controller 8 follows the program stored in the memory, the setting and command input by the user via the input means 7, the power consumption and rotational speed transmitted from the control unit 33, and the three output from the waveform shaping unit. Based on the line voltage value between the phases of the phase alternating current, a signal for instructing the control of the engine 21 and the control of the converter 31 and the inverter 32 is transmitted to the ECU 26 and the control unit 33.

  The controller 8 is provided with a rotation speed correspondence table showing a correspondence relationship between the power consumption on the load side and the rotation speed of the engine 21, and the logic of the engine 21 is referred to by referring to the rotation speed correspondence table based on the power consumption. Find the rotation speed.

  The rotation speed correspondence table is based on the fuel consumption curve of the engine 21 and is a predetermined value that can correspond to the load fluctuation that can occur with respect to the detected power consumption on the load side and the output of the engine 21 necessary to generate the power consumption on the load side. In order to generate the output with the margin value added, the relationship with the rotational speed of the engine 21 that is the smallest fuel consumption is set, and the power consumption is low or zero based on the idle rotational speed and the maximum rotational speed. In this case, the rotational speed of the engine 21 is set to be the idle rotational speed. Thereafter, in this embodiment, the rotational speed of the engine 21 increases linearly as the power consumption increases, and is clamped at the maximum rotational speed. To be set.

  In the present embodiment, the correspondence relationship between the power consumption and the rotation speed is stored in the controller 8 as a rotation speed correspondence table. Instead, the correspondence relationship between the power consumption and the rotation speed is used as a calculation formula. May be stored in the controller 8.

  In this embodiment, the load status is detected by the power consumption. Instead, when the load status is detected by the current value of the load, the correspondence relationship between the current value and the rotation speed is indicated by the rotation speed correspondence. You may memorize | store in the controller 8 as a table or a calculation formula.

  The predetermined margin value that can cope with the load fluctuation described above may be a constant value with respect to the power consumption on the load side, and the predetermined margin value is increased when the power consumption on the load side is small. When the power consumption on the load side is large, it may be reduced.

  Note that the target rotational speed to be transmitted to the ECU 26 of the engine 21 at the time of transition to the load startup mode, transition to the normal operation mode, or transition to the additional load startup mode will be described in the operation description described later.

  In this embodiment, the line voltage value between each phase of the three-phase alternating current output from the waveform shaping unit is input, and the output voltage output to the controller so that the line voltage value becomes the output voltage value set by the input means. The command signal is corrected.

[Description of operation]
The operation of the engine-driven inverter generator 1 of the present invention configured as described above will be described with reference to FIGS.

(1) Pre-start operation The engine-driven inverter generator 1 according to the present invention includes a frequency setting means 71, an output voltage setting means 72, a connection load setting means 74 provided in the input means 7 before the engine 21 is started, The minimum rotation speed setting means 75 is operated to set the output frequency, the output voltage value, the size of the load to be connected, and the minimum rotation speed (FIG. 4: S2).

  When these setting means 71, 72, 74, 75 are mechanical switches such as a changeover switch and a volume switch (variable resistor), this operation is performed by the engine-driven inverter generator 1 of the present invention. However, when all of these setting means are realized by a screen display on a liquid crystal screen having a touch panel function, the starter switch 76 is set to “ A state in which the liquid crystal screen, the controller 8, the ECU 26, the control unit 33 and the like are energized by operating to the “operation” position (FIG. 4: S1), and input via the touch panel is enabled. The above-described various settings are performed (FIG. 4: S2).

  When the setting means is realized by a touch panel or the like, the controller 8 may be configured to hold the setting even after the engine-driven inverter generator 1 is stopped. In this case, the setting at the previous use is used. If there is no change, input of the above settings may be omitted.

(2) Start As described above, after the setting by the setting means 71, 72, 74, 75 provided in the input means 7 is completed, the starter switch 76 is moved from the “running” position to the “starting” position. The cell motor (not shown) provided in 21 is energized, and the engine 21 is started by the rotation of the cell motor (FIG. 4: S3). After the engine 21 is started, the starter switch 76 is returned to the “operation” position. Continue operation.

In this embodiment, when the rotational speed of the engine reaches a predetermined rotational speed (for example, 1200 min ⁻¹ ) (FIG. 4: S4), the controller 8 sends an output start signal (PON signal) to the control unit 33. The control unit 33 that outputs (FIG. 4: S5) and receives the PON signal turns on the gate of the inverter 32 (FIG. 4: S6), and is ready to start output from the inverter.

(3) Warm-up operation The above-described control means 8 may perform the warm-up operation of the engine 21 according to a predetermined condition when the engine 21 is started.

  In the present embodiment, when the controller 8 determines that the engine coolant temperature is lower than the set temperature based on an electrical signal from a coolant temperature sensor (not shown) provided in the engine 21, the controller 8 The ECU 26 is caused to perform a warm-up operation that operates until the cooling water temperature of the engine 21 reaches the set temperature without shifting to a load start mode described later.

In this embodiment, as an example, when the engine coolant temperature detected by the temperature sensor is less than 20 ° C., the engine is uniformly set to 1300 min ⁻¹ regardless of various settings until it reaches 20 ° C. or higher. It was configured to perform a warm-up operation at a constant speed (FIG. 4: S7, S8).

  In the case of performing a predetermined warm-up operation, since the load is connected after the warm-up of the engine is completed, it is possible to more reliably prevent the engine from being stopped due to the load connection.

(4) Load start mode As described above, after the engine 21 is started, when the temperature of the engine 21 exceeds a predetermined temperature, the warm-up operation is terminated, and the controller 8 shifts to the load start mode (FIG. 5: S9). .

In this load start mode, the engine is operated at a constant speed at a preset rotational speed in accordance with the magnitude of the connection load set by the connection load setting means 74 described above. The load is configured so that any one of a plurality of preset loads can be selected, and the correspondence between the preset load stored in the controller 8 and the load starting rotational speed is Based on the magnitude of the load selected by the connected load setting means, a predetermined load starting rotational speed is set as a target rotational speed, and this target rotational speed is transmitted to the ECU 26. In the configuration of this embodiment in which the setting by the connection load setting means 74 is selected from among the three types of “light load”, “standard”, and “heavy load”, “light load” is used as an example. Load starting rotation speed when setting “Load” (rated motor load of 7.5 kW or less) is set to 1300 min ⁻¹ (FIG. 5: S10, S11), “Standard” (Motor load of rating 11 kW or less) is set load start rotational speed 2200Min ^-1 (Fig. 5: S10, S12), "heavy load" 2800min load starting rotation speed of setting (following motor load rated 15 kW) ^-1 (Fig. 5: S10, S13) It was.

  The load starting rotational speed may be an engine rotational speed necessary for connecting a load having a set size. For example, it is experimentally obtained in advance for each model of the engine-driven inverter generator 1. I can leave.

  In the above description, the size of the load to be connected can be set by selecting any one of “light load”, “standard”, and “heavy load”. As described above, a volume switch (variable resistor) or the like may be provided as the connection load setting means 74 so that a load of an arbitrary magnitude can be selected steplessly from a load within a predetermined numerical range. A momentary switch may be provided as the setting means 74, and the magnitude of the load may be arbitrarily set stepwise according to the number of times the momentary switch is operated.

  In this way, when the magnitude of the load to be connected can be arbitrarily set, the rotation speed of the engine 21 and the load that can be connected as shown in FIG. The correspondence relationship between the magnitude of the connection load to be set and the load starting rotational speed is stored in the storage means of the controller 8 in accordance with the relationship obtained experimentally by, for example, experimentally determining the correspondence relationship between the sizes. Alternatively, the engine may be driven at a load starting rotational speed corresponding to the set connection load.

  The connection load can be easily set by selecting the size of the load to be connected from a plurality of preset sizes, and can be arbitrarily set from a predetermined selection range by operating the volume switch. By making it possible to set, it is possible to make finer settings that accurately correspond to the size of the connected load.

  In this way, the engine speed was set with the engine running in "load start mode" where constant speed control is performed at the load start speed corresponding to the set connection load. Connect the load corresponding to the size of the load.

  In this embodiment, the breaker 5 provided between the waveform shaping unit 4 and the output terminal block 6 is a circuit between the waveform shaping unit 4 and the output terminal block 6 when the output voltage falls below a predetermined value (about 100 to 110 V as an example). Therefore, the load is not connected to the inverter 32 when the engine is started.

  Therefore, after the engine 21 is started, after shifting to the load starting mode, the user operates the breaker 5 described above, and when the load itself is provided with a switch, the switch is further turned ON. Connect the load.

  When the load is thus connected, the load is activated and the current detecting means 35 provided on the load side of the inverter 32 detects the change on the load side, and this detection signal is sent via the control unit 33. The received controller 8 determines that the load is activated, ends the load activation mode, and shifts to the normal operation mode.

  In the present embodiment, the load-side current value detected by the current detection means 35 is detected to be equal to or greater than a predetermined value (1A as an example) (FIG. 5: S14), and this detection signal is continuously output for a set time ( When received, the controller 8 determines that the load has been activated (FIG. 5: S15), ends the operation in the load activation mode (FIG. 5: S16), and shifts to the normal operation mode described later. I made it.

  As described above, in the engine-driven inverter generator 1 according to the present invention, when the load is connected, the engine is controlled at an appropriate rotation speed according to the magnitude of the load to be connected. It is possible to achieve both conflicting demands for preventing the descent and realizing low fuel consumption.

  In this embodiment, in the load start mode, constant speed control is performed at the load start rotation speed before and after the load start. The controller 8 refers to the rotation speed correspondence table and corresponds to the power consumption that is the load status. A logical rotational speed is obtained, and this logical rotational speed is compared with the set load starting rotational speed. When the logical rotational speed is equal to or lower than the load starting rotational speed, the ECU 26 of the engine 21 sets the load starting rotational speed to the target rotational speed. When the logical rotational speed is higher than the load starting rotational speed, the logical rotational speed may be transmitted to the ECU 26 as the target rotational speed.

  Alternatively, in the load start mode, the controller 8 compares the load power consumption, which is the load status, with the rated output of the load, which is the size of the load set by the connected load setting means. If the output is larger than the rated output, the logical rotational speed corresponding to the load condition is obtained by referring to the rotational speed correspondence table, and this logical rotational speed is transmitted to the ECU 26 as the target rotational speed. If the output is less than the rated output, the load starting rotation speed corresponding to the magnitude of the load may be transmitted to the ECU 26 as the target rotation speed.

  By configuring in this way, even if the power consumption of the connected load exceeds the power consumption assumed in advance, this difference is corrected, and the engine stops and the output voltage drops. Can be prevented.

(5) Normal operation mode As described above, when the operation in the load starting mode is completed and the operation mode is shifted to the normal operation mode (FIG. 6: S17), the controller 8 provides the above-mentioned minimum rotational speed provided in the input means 7. In the minimum rotation speed setting means 75, “auto (mode)” or “power (mode) is set so that the engine is controlled at a normal rotation speed that is a predetermined rotation speed with the minimum rotation speed set by the setting means 75 as a lower limit. Is selected (FIG. 6: S18), and when “AUTO (MODE)” is selected, 1300 min ⁻¹ is set as the minimum rotation speed as an example (FIG. 6: S19). ”Is selected as an example, 2200 min ⁻¹ is set as the minimum rotation speed (FIG. 6: S20). If“ Auto (Mode) ”is selected, the error occurs when the rotation speed is 1300 min ^−1. 13kW, which is a size that can be output by the electric machine, is set as a reference power that is a reference load condition (FIG. 6: S21), and when “power (mode)” is selected, when the rotation speed is 2200 min ⁻¹ The reference power is 22 kW, which is a size that can be output to the power source (FIG. 6: S21). Then, the power consumption detected by the control unit 33 is received as information indicating the actual load status (FIG. 6: S23), and the power consumption is compared with the reference power corresponding to the set minimum rotation speed. (FIG. 6: S24) When the power consumption is larger than the reference power, the logical rotation speed is obtained based on the power consumption with reference to the rotation speed correspondence table, and the ECU 26 of the engine 21 is set with the logical rotation speed as the target rotation speed. (FIG. 6: S25), and when the power consumption is equal to or lower than the reference power, the set minimum rotational speed is transmitted to the ECU 26 of the engine 21 as the target rotational speed (FIG. 6: S26).

FIG. 7 shows a flow of another normal operation mode in place of the flow of the normal operation mode described with reference to FIG. In this flow, when the operation in the load start mode is completed and the operation mode is shifted to the normal operation mode (FIG. 7: S17), the controller 8 sets the minimum rotation speed setting means 75 provided in the input means 7 to the minimum value. The minimum rotation speed setting means 75 selects either “auto (mode)” or “power (mode)” so that the engine is controlled at a normal rotation speed whose lower limit is the rotation speed (FIG. 7: S18). When “Auto (Mode)” is selected, 1300 min ⁻¹ is set as the minimum rotation speed as an example (FIG. 7: S19), and when “Power (Mode)” is selected, 2200 min ⁻¹ is set as the minimum. The rotation speed is set (FIG. 7: S20), and the power consumption detected by the control unit 33 is received as information indicating the actual load status (FIG. 7: S23). The logical rotation speed is obtained based on the power consumption with reference to the blue (FIG. 7: S29), the set minimum rotation speed is compared with the logical rotation speed (FIG. 7: S30), and the logical rotation speed is the minimum rotation. If it is higher than the speed, the logical rotational speed is transmitted as the target rotational speed to the ECU 26 of the engine 21 (FIG. 7: S31). If the logical rotational speed is less than or equal to the minimum rotational speed, the minimum rotational speed is set to the target rotational speed. To the ECU 26 of the engine 21 (FIG. 7: S32).

Is a at the lowest rotational speed setting means 75 in this embodiment either the possible selection of the "automatic (mode)" or "power (mode)", 1300Min ^-1 in automatic mode as an example, the power mode 2200Min ^{- 1} is set as the above-mentioned minimum rotation speed, and the engine rotation speed control is controlled with this minimum rotation speed as the lower limit. However, as the above-mentioned minimum rotation speed setting means 75, the changeover switch shown in FIG. In addition, the minimum rotation speed can be set steplessly by providing a volume switch (variable resistor) or a momentary switch that can be changed for each predetermined value with each changeover switch. When an arbitrary value can be set in stages, the minimum rotation speed corresponding to the setting is set as the lower limit value of the normal rotation speed.

  Further, the correspondence relationship between the state of the connected load and the minimum rotational speed is stored in the storage means of the controller 8 in advance, and the controller 8 determines the correspondence relationship according to the load condition detected by the calculated power consumption. The minimum rotation speed may be set based on the above.

  As an example, the controller 8 may be configured such that the controller 8 automatically sets the minimum rotational speed in accordance with the magnitude of the load set by the connection load setting means 74.

Further, when the engine is operated at the minimum rotational speed, the rotational speed set by the minimum rotational speed setting means 75 may be changed based on the load condition. In this case, at the minimum rotational speed, If the fluctuation range which is the difference between the maximum value and the minimum value of the power consumption during the predetermined time during operation is acquired and the fluctuation range is smaller than the predetermined fluctuation range, for example, the minimum rotation speed set to 1300 min ⁻¹ Is reduced to 100 min ⁻¹ to 1200 min ^−1, and accordingly, the engine speed is set to 1200 min ⁻¹ . When the engine is operating at the minimum rotation speed, if the power consumption becomes larger than the reference power, the engine rotation speed increases to a rotation speed corresponding to the power consumption and decreases to 1200 min ⁻¹ . The minimum rotation speed may return to the minimum rotation speed 1300 min ⁻¹ initially set by the minimum rotation speed setting means.

  With this configuration, when the change in power consumption on the load side is not large and stable, operation is performed at a rotational speed with a relatively large margin in preparation for sudden load fluctuations. As the power consumption on the side becomes smaller and the change is less stable, the engine can be driven at a rotational speed closer to the minimum necessary rotational speed by reducing the extra rotational speed, and therefore consumed by the engine. The amount of fuel used can be minimized.

Alternatively, the method of changing the minimum rotation speed is not the above-described method, but the maximum value of power consumption for a predetermined time during operation at the minimum rotation speed is obtained, and the minimum rotation speed and the minimum rotation speed stored in advance are obtained. Based on the correspondence with the size that can be output by the generator, the size (13 kW as an example) that the generator can output at the set minimum rotation speed (1300 min ⁻¹ as an example) is obtained, and the acquired consumption When the maximum value of power is compared with the obtained output possible size (13 kW as an example) and the maximum value of power consumption is smaller than the obtained output possible size (13 kW as an example), 1300 min ^-1 The minimum rotation speed set in ( ^{1) is} reduced by 100 min ⁻¹ to 1200 min ^−1, and accordingly, the engine rotation speed is set to 1200 min ⁻¹ . When the engine is operated at the minimum rotation speed of 1200 min ⁻¹ , if the power consumption becomes larger than 12 kW that the generator can output at the minimum rotation speed of 1200 min ⁻¹ , the engine rotation rate increases the rotational speed corresponding to the power consumption, may be returned to the minimum rotation speed is the lowest speed 1300Min ^-1 which was initially set at a minimum rotational speed setting means is reduced to 1200min ^-1.

  With this configuration, when the engine is operating at the minimum rotation speed, if the power consumption on the load side is smaller than the size that can be output at the minimum rotation speed, it is possible to prepare for the sudden load fluctuation. Judging that the engine has sufficient output power, the engine can be driven at a rotational speed closer to the minimum necessary rotational speed, and therefore the fuel consumed by the engine can be minimized. It has become.

  The operation in the normal operation mode is performed until the user commands the start of the additional load start mode via the additional load start mode start command input means 73 provided in the input means 7 (FIG. 6, 7: S27). When the start of the additional load start mode is commanded, the operation in the normal operation mode ends (FIGS. 6 and 7: S28), and the operation in the additional load start mode described later is started.

(6) Additional load start mode While the operation in the normal operation mode is being performed, the user operates the additional load start mode start command input means 73 provided in the input means 7 to shift to the additional load start mode. When commanded (FIGS. 6 and 7: S27), the operation in the normal operation mode ends (FIGS. 6 and 7: S28), and the operation in the additional load start mode is started (FIG. 8: S33).

As a result, the controller 8 transmits the preset additional load rotational speed to the ECU 26 as the target rotational speed, and the ECU 26 that has received this transmits the rotational speed of the engine 21 as the additional load rotational speed, which is an example in this embodiment. Increase to 2800 min ⁻¹ (FIG. 8: S34).

  In this embodiment, the load starting rotational speed in the additional load starting mode is set to a constant rotational speed. Instead, a plurality of additional load starting rotational speeds are set, and the total of the load being operated and the load to be additionally connected is set. Depending on the set additional load rotational speed, the corresponding rotational speed may be selected, or the additional load starting rotational speed can be set to an arbitrary value within a predetermined numerical range and operated. The additional load starting rotational speed may be selected according to the total of the middle load and the load to be additionally connected.

  The additional load starting rotational speed, which is the rotational speed of the engine 21 in the additional load starting mode, can be selected from a predetermined numerical group or from a predetermined numerical range, and the magnitude of the load to be additionally started, Based on the total amount of loads already in operation, an appropriate passing load starting rotational speed can be selected, which can more reliably realize engine stop, output voltage drop prevention, and low fuel consumption. it can.

As an example, in an engine-driven inverter generator with a rated output power of 22 kW, “auto” is set by the minimum speed setting means 75 and a motor load is connected as a load. If the power consumption of the finished load is in the range of 0 to 13 kW, the normal rotation speed is 1300 min ⁻¹ , which is the minimum rotation speed, and if the power consumption of the connected load exceeds 13 kW, In response to the increase in power consumption of the connected load, the normal rotation speed is increased, and when the load power consumption reaches 22 kW, the normal rotation speed is controlled to the rated rotation speed of 2200 min ⁻¹ . assumed, in the engine-driven inverter generator 1 is operated at a rotational speed of 1300Min ^-1 in power consumption of connected motor load is 7.5kW, further the rated output 7.5kW motor with Attach additional data load, the case where the attempt to start the motor load.

In such a state, in a state where the normal rotation speed is maintained at the minimum rotation speed of 1300 min ⁻¹ , the load that can be additionally connected decreases as the power consumption of the connected load increases.

  When starting a motor load, a starting current that is several times the rated current flows, so the normal engine-driven generator 1 must have the ability to output approximately three times the rated output of the motor load. However, the engine-driven inverter generator of this embodiment temporarily reduces the frequency of the alternating current output from the inverter by the function of the control unit that controls the inverter, and the breaker temporarily sets the output voltage to the circuit. Since it is reduced to a predetermined value that does not open, it is sufficient if it has the ability to output twice as much power as the rated output of the motor load. From this, the power consumption of the connected motor load is 7.5 kW, and in order to connect and start up a motor load with a rated output of 7.5 kW, the power consumption of the motor load during operation is 7.5 kW. It is necessary to be able to output a total power of 22.5 kW with 15 kW, which is twice the rated output of the motor load to be started.

However, when trying to output 22.5kW of power, the rated output power (22kW) of the engine-driven inverter generator operating at the rated rotational speed of 2200min ^-1 will be exceeded, and the engine will stop or the output voltage will The descent may cause the motor load that has been started to stop.

On the other hand, when the rotational speed of the engine 21 is temporarily increased to 2800 min ⁻¹ beyond the rated rotational speed of 2200 min ⁻¹ , the power that can be output by the generator 1 is temporarily reduced to the rated output power ( 22 kW) to 28 kW, the additional connectable load also temporarily increases, allowing for a margin. Even when a relatively large additional load is connected, the engine stops or the output voltage drops Can be prevented.

As in the previous example, even when a motor load that requires a starting current several times higher than the rated current is assumed as a load to be additionally connected, the engine rotation temporarily occurs when the load is connected. In the example of the engine-driven inverter generator 1 described above, if the speed can be increased to a rotational speed at which electric power of 22.5 kW or more can be temporarily output by increasing the speed above the rated rotational speed, the power consumption is 7.5 kW. With the motor load connected, a motor load with a rating of 7.5 kW can be additionally started. After the load is connected, the load shifts to normal operation and power consumption decreases (in the above example, 2 if the decrease power consumption of the motor load is below 15 kW), in the example of the rated output power (above in 2200min ^-1) in the example rotational speed rated speed (of the foregoing engine operating in the range of 22 kW) DOO are possible, operation of the engine 21 at the rated speed or more, well a relatively short time basis at the time of startup of the motor load to be added, not take a large burden to the engine 21.

In the above example, the example in which the additional load starting rotational speed is set to a rotational speed higher than the rated rotational speed of the engine 21 is described as an example. For example, the power consumption of the connected motor load is 7.5 kW and 1300 min ⁻ Connected to the engine-driven inverter generator 1 that is operated so that a rotational speed of ¹ and power of 13 kW can be output, as if an additional 5.5 kW motor load was connected and started. The total of the load power consumption 7.5kW and 11kW, which is twice the rated output of the load to be additionally connected (18.5kW), is within the range of the rated output power (22kW) of the engine-driven inverter generator 1, etc. Depending on the magnitude of the additional starting load, the additional load starting rotational speed may be set within a range not exceeding the rated rotational speed of the engine 2200 min ⁻¹ .

As described above, when the operation shifts to the operation of the additional load start mode in which the engine speed is increased to a predetermined additional load start speed (2800 min ⁻¹ as an example), the controller 8 sets the load current as a value indicating the load status. The controller 8 receives a detection signal from the current detection means 35 for detecting the load, and based on the received detection signal, the controller 8 acquires the load current value over time, and after starting the additional load startup mode, the first acquired value is used as the reference current value. Is temporarily stored (FIG. 8: S35).

Then, the counter elapsed time _{T 1} and the extension time _{T 2} with a 0 (reset), starts counting of the counter (FIG. 8: S36). Thereafter, the load current is received again (FIG. 8: S37), and when the acquired load current is equal to or greater than a current value obtained by adding a predetermined value (3A in this embodiment) to the stored reference current value (FIG. 8: S38), and rewrite updates the acquired load current as a reference current value (Fig. 8: S39), rewrite this time by adding 10 seconds to the counter elapsed time _{T 1} of the present time to _(T 1 +10) as an extension time _{T 2} Update (FIG. 8: S40) and receive the load current again (FIG. 8: S37). Thus while the load current continues to increase, repeat the update of the extra time T ₂ and the reference current value.

When the load current is received again (FIG. 8: S37) and the newly acquired load current is less than the current value obtained by adding a predetermined value (3A in this embodiment) to the stored reference current value, counter elapsed time _{T 1} is determined whether 30 seconds or more (Figure 8: S41), and when less than 30 seconds receive again load current (Figure 8: S37), stores the counter elapsed time _{T 1} and at least 30 seconds and are compared with the extension time _{T 2} (Fig. 8: S42), the counter elapsed time _{T 1} is received again load current when less than the extension time _{T 2} (Fig. 8: S37), the counter elapsed time _{T 1} is extended when the time _{T 2} or terminates the additional load startup mode (Figure 8: S43). If such increase of the load current is not detected, or if the increase of the load current is stopped is a predetermined time has passed (elapsed counter elapsed time T ₁ is 30 seconds, and extension time T ₂ has elapsed) was added after load start Exit the mode and enter normal operation mode.

  The controller 8 stores the initial load current in the reference current value (FIG. 8: S35), and if no current higher than 3 A is detected from the initial reference current value in 30 seconds, an additional Assuming that the load connection has not been made, the additional load start mode is terminated (FIG. 8: S43), thereby automatically returning from the additional load start mode in which the engine 21 operates at high speed to the normal operation mode. Fuel consumption has been reduced.

DESCRIPTION OF SYMBOLS 1 Engine drive type inverter generator 2 Electric power generation part 21 Engine 22 Generator main body 24 Electronic governor 25 Rotational speed sensor 26 Engine control unit (ECU)
DESCRIPTION OF SYMBOLS 3 Power conversion part 31 Converter 32 Inverter 33 Control unit 34 Current detection means 35 Current detection means 4 Waveform shaping part 41 AC reactor 42 Filter capacitor 43 Common mode choke 5 Breaker 6 Output terminal block 7 Input means 71 Frequency setting means 711 Frequency adjustment volume 712 Frequency changeover switch 72 Output voltage setting means 721 Output voltage adjustment volume 722 Output voltage changeover switch 73 Additional load start mode start command input means 74 Connected load setting means 75 Minimum rotation speed setting means 76 Starter switch 8 Controller

Claims (12)

An engine, a generator main body driven by the engine, a converter that converts alternating current generated in the generator main body into direct current, and an inverter that converts direct current output from the converter into predetermined alternating current and supplies the alternating current to a load In the engine-driven inverter generator in which the rotational speed of the engine is variable according to the load condition,
Providing a connection load setting means for setting a magnitude of a load connected to the engine-driven inverter generator;
After starting the engine, performing a load starting mode for operating the engine at a predetermined load starting rotational speed or higher corresponding to the magnitude of the load set by the connected load setting means,
After detecting the start of the load in the load start mode, the load start mode is ended, and the engine is shifted to a normal operation mode in which the engine is operated at a predetermined rotational speed according to the load condition. Control method of drive type inverter generator. In the load start mode,
Detecting the load status connected to the engine-driven inverter generator as a load size, comparing the detected load size with the set load size,
When the detected load magnitude is larger than the set load magnitude, the detected load magnitude is calculated based on the correspondence relationship between the load magnitude stored in advance and the engine speed. The logical rotational speed of the engine is obtained, and the logical rotational speed is set as the target rotational speed. When the detected load is equal to or smaller than the set load, the load starting rotational speed is set as the target rotational speed. As speed,
2. The control method for an engine-driven inverter generator according to claim 1, wherein the target rotational speed is compared with an actual rotational speed of the engine, and the engine is controlled so that the target rotational speed and the actual rotational speed coincide with each other. . In the load start mode,
The condition of the load connected to the engine-driven inverter generator is detected, and the logical rotation speed of the engine is obtained from the detected load condition based on the correspondence relationship between the load condition stored in advance and the rotation speed of the engine. ,
The load starting rotation speed is compared with the logical rotation speed obtained based on the load status. When the logical rotation speed is higher than the load starting rotation speed, the logical rotation speed is set as a target rotation speed. When the logical rotational speed is equal to or lower than the load starting rotational speed, the load starting rotational speed is set as a target rotational speed,
2. The control method for an engine-driven inverter generator according to claim 1, wherein the target rotational speed is compared with an actual rotational speed of the engine, and the engine is controlled so that the target rotational speed and the actual rotational speed coincide with each other. . In the load start mode,
The condition of the load connected to the engine-driven inverter generator is acquired as a value indicating the magnitude of the load, and the value indicating the magnitude of the load is continuously set for a preset time and exceeds a predetermined value higher than 0. The control method for an engine-driven inverter generator according to any one of claims 1 to 3, wherein when the load is maintained, the start of the load is detected.   5. The method for controlling an engine-driven inverter generator according to claim 1, wherein the state of the load is detected by power consumption of a load connected to the engine-driven inverter generator. 6.   The method of controlling an engine-driven inverter generator according to any one of claims 1 to 4, wherein the state of the load is detected by a current value of a load connected to the engine-driven inverter generator. An engine, a generator main body driven by the engine, a converter that converts alternating current generated in the generator main body into direct current, and an inverter that converts direct current output from the converter into predetermined alternating current and supplies the alternating current to a load In the engine-driven inverter generator in which the rotational speed of the engine is variable according to the load condition,
Input means for inputting various settings and / or operation instructions for the engine-driven inverter generator;
Load status detection means connected to the engine-driven inverter generator;
A controller for controlling the operation of the engine, the inverter and the converter based on various settings and operation instructions input via the input means and the load status detected by the load status detection means is provided.
The input means includes connection load setting means for setting a magnitude of a load connected to the engine-driven inverter generator,
Said controller,
After the engine is started, a load start mode is prepared to start the load by operating the engine at a predetermined load start rotational speed or higher according to the load set by the connected load setting means, and After determining that the load has been activated based on the load status detected by the detection means, the load activation mode is terminated, and the engine is shifted to a normal operation mode in which the engine is operated at a predetermined rotational speed according to the load status. An engine-driven inverter generator characterized by being configured to do so.   The controller compares the load magnitude in the detected load situation with the set load magnitude, and if the detected load magnitude is greater than the set load magnitude, Based on the correspondence relationship between the magnitude of the load stored in advance and the engine speed, the logical speed of the engine is obtained from the detected magnitude of the load, and the detected logical speed is set as the target speed. When the magnitude of the load is less than or equal to the set magnitude of the load, the load starting rotational speed is set as the target rotational speed, the target rotational speed is compared with the measured rotational speed of the engine, and the target rotational speed is compared with the measured rotational speed. 8. The engine-driven inverter generator according to claim 7, further comprising a function of controlling the engine so that the rotational speed matches. Based on the correspondence relationship between the load condition stored in advance and the engine rotation speed in the controller, the logical rotation speed of the engine is obtained from the detected load condition;
The load starting rotational speed is compared with the logical rotational speed obtained based on the load condition, and when the logical rotational speed is higher than the minimum rotational speed, the logical rotational speed is set as a target rotational speed. When the logical rotational speed is equal to or lower than the minimum rotational speed, the minimum rotational speed is set as the target rotational speed, the target rotational speed is compared with the actual rotational speed of the engine, and the target rotational speed and the actual rotational speed are determined. 8. The engine-driven inverter generator according to claim 7, further comprising a function of controlling the engine so as to match. The controller
When in the load start mode, the load status detected by the load status detection means is received as a detection signal;
From the received detection signal, obtain a value indicating the magnitude of the detected load and the duration of the value,
8. The apparatus according to claim 7, wherein the load is determined to have been activated when the acquired value is maintained at a predetermined value higher than 0 for a preset time continuously. The engine drive type inverter generator of any one of -9.   The engine-driven inverter according to any one of claims 7 to 10, wherein the load condition detecting means detects power consumption of a load connected to the engine-driven inverter generator as the load condition. Generator.   The engine-driven inverter according to any one of claims 7 to 10, wherein the load status detection means detects a current value of a load connected to the engine-driven inverter generator as the load status. Generator.

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