JP2001069795A - Engine power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an inverter circuit by a control signal corresponding to the operation state of the inverter circuit by an engine generator with a control part for considering dead time data for forming the pulse of first and second PWM signals. SOLUTION: In an engine generator 100 that rectifies voltage generated by an AC generator 50 for outputting a DC voltage charged at a DC power supply part 120 as an AC voltage, an inverter circuit 130 is composed of a bridge circuit according to a switching element, a control part 310 for outputting a control signal for turning on and off the switch element of the bridge circuit is provided, and the control signal is outputted based on continuity time data and dead time data stored in the control part 310.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable engine generator for outputting an AC voltage such as 100 volts by rotating a generator by an engine.

[0002]

2. Description of the Related Art Today, small generators that can be moved to a required place using a gasoline engine or a diesel engine and that can produce an output of several kilowatts have been frequently used. Have been. As an engine generator capable of this movement, a power generator that outputs a single-phase AC voltage of 50 Hz or 60 Hz by setting the average output voltage to about 100 volts and the engine speed to a constant speed. There was a machine.

However, recently, there is a type in which an output voltage of an AC generator rotated by an engine is once converted into a DC voltage, and an inverter is used to form an output voltage having a constant frequency of 50 Hz or 60 Hz ( For example,
JP-A-63-114527, JP-A-63-30272
No. 4). It should be noted that a small engine generator capable of outputting about several kilowatts to about ten kilowatts using an engine is not limited to a case where the generator is brought into a place of use and is always movable so as to perform a power generation operation. For example, when the usage period of the device is to be continued, it may be fixedly installed and operated.

In an engine generator employing this inverter, as shown in FIG. 11, an AC generator 50 rotated by the engine, a DC voltage generation circuit 110 using a rectifier diode 115 and a thyristor 111, and a required number of generators are provided. The DC power supply unit 120 includes a large-capacity capacitor 121 in parallel with a capacitor, an inverter circuit 130 using a power transistor, and a low-pass filter 140. Further, as control circuits for driving and controlling power circuits such as the DC voltage generation circuit 110 and the inverter circuit 130, a PWM signal generation circuit 250, a voltage limit circuit 240, an overload detection circuit 260, an inverter drive circuit 255, etc. Have. The engine generator 100 also has a smoothing circuit 210 and a constant voltage circuit 235 as a power supply for driving these control circuits.

As an AC generator 50 for rotating a rotor by this engine, a generator having a three-phase output winding 51 and a single-phase output winding 55 is often used. The three-phase output winding 51 has a maximum output of several hundred volts and can output about several tens of amps, and the single-phase output winding 55 has several tens of volts and can output about tens of amps. Many. The DC voltage generation circuit 110 to which the output terminal of the three-phase output winding 51 is connected,
A rectifying bridge circuit using three rectifying diodes 115 and three thyristors 111 is connected. Both output terminals of the rectifying bridge circuit are connected to both ends of a main smoothing capacitor 121 serving as a DC power supply unit 120, and a capacitor is connected. It charges the 121.

The gate terminal of each thyristor 111 in the DC voltage generating circuit 110 is connected to a voltage limiting circuit 240,
By controlling the conduction angle of each thyristor 111, the voltage across the main smoothing capacitor 121 serving as the DC power supply unit 120 is adjusted. The inverter circuit 130 is configured by a bridge circuit using four power transistors. In the inverter circuit 130, the first transistor 131
And the third transistor 133 are connected in series to the DC power supply unit 120, and the second transistor 132 and the fourth transistor 134 are connected in series to the DC power supply unit 120. Also, the first
A middle point between the transistor 131 and the third transistor 133 is connected to a first output terminal 151 via a low-pass filter 140, and a middle point between the second transistor 132 and the fourth transistor 134 is connected to a second output terminal via a low-pass filter 140. Connected to terminal 152. Further, the base of the first transistor 131 and the base of the fourth transistor 134 are connected in common to the inverter drive circuit 255, and the base of the second transistor 132 and the base of the third transistor 133 are connected in common to the inverter drive circuit 255. are doing.

[0007] The inverter drive circuit 255
The first PWM signal output to the transistor 131 and the fourth transistor 134 and the second PWM signal output to the second transistor 132 and the third transistor 133 are high-frequency pulse signals of several kilohertz or more. The pulse width is sequentially changed in a cycle of 50 Hz or 60 Hz, and the amount of change in the pulse width is a signal that is sequentially increased or decreased in a sinusoidal manner.

The first PWM signal and the second PWM signal have opposite phases. For this reason, when the first transistor 131 and the fourth transistor 134 are made conductive by the first PWM signal to set the midpoint between the first transistor 131 and the third transistor 133 to the voltage VD of the DC power supply unit 120, the second transistor 132 The midpoint of the second transistor 132 and the fourth transistor 134 is set to 0 volt, and the second PWM signal is
When the third transistor 133 is turned on, the midpoint between the first transistor 131 and the third transistor 133 is set to 0 volt, and the midpoint between the second transistor 132 and the fourth transistor 134 is set to the voltage VD. It is said.

The midpoint potential between the first transistor 131 and the third transistor 133 is 0 as shown in FIG.
The voltage and the voltage VD of the DC power supply 120 are switched at high speed,
In addition, the duration of the DC power supply voltage VD changes sequentially.
Also, as shown in FIG. 12B, the midpoint potential between the second transistor 132 and the fourth transistor 134 switches between the voltage VD of the DC power supply 120 and 0 volts at high speed, and the duration of the DC power supply voltage VD. Change sequentially.

Therefore, the first output voltage and the second output voltage that have passed through the low-pass filter 140 are sine wave voltages of 50 Hz or 60 Hz as shown in FIG. The voltage and the voltage of the second output terminal 152 are formed as a 50 Hz or 60 Hz AC output voltage in which the maximum value and the minimum value are shifted by half a cycle. And
When the first PWM signal controls the first transistor 131 and the fourth transistor 134, and when the second PWM signal controls the second transistor 132 and the third transistor 133, the first transistor 131 to the fourth transistor 134 are controlled.
All transistors 131, 132, 13
In order to prevent a short circuit from occurring in the inverter circuit 130 due to the conductive state of the inverter circuit 130, a dead time may be provided to the control signals as the first PWM signal and the second PWM signal.

In order to provide a dead time for the first PWM signal and the second PWM signal as the control signals, FIG.
As shown in (1), a first waveform shaping circuit 258 and a second waveform shaping circuit 259 are provided in the inverter drive circuit 255, a PWM control signal is input to the first waveform shaping circuit 258, and the PWM control signal is inputted to the first waveform shaping circuit 258. 1st pulse width narrower than H pulse width
A PWM signal is formed and output, and the PWM control signal is inverted by an inverter 257 to form a second waveform shaping circuit 259.
And the second waveform shaping circuit 259 outputs the PWM control signal L
A second PWM signal having an H pulse width smaller than the level pulse width is formed, amplified by an amplifier circuit such as a transistor, and output.

The H level of the first PWM signal and the second PWM signal
When narrowing the pulse width, as shown in FIG.
The first PWM signal having a narrowed pulse width by slightly delaying the rising edge of the H pulse is formed by the first waveform shaping circuit 258 by the logical product of the input PWM control signal and a signal obtained by slightly delaying this control signal. Similarly, the PWM control signal inverted by the inverter 257 is supplied to the second waveform shaping circuit 2.
In some cases, the second PWM signal is formed by ANDing the inverted PWM control signal and a signal obtained by slightly delaying the inverted PWM control signal.

Further, the first waveform shaping circuit 258 and the first waveform shaping circuit 258 include a circuit which inclines the rising edge and the falling edge of the PWM control signal, adjusts the threshold value, changes the width of the H pulse, and returns the edge to a steep pulse. When the pulse width is narrowed using the two-waveform shaping circuit 259, the H level of the first PWM signal
A dead time t may be formed between the pulse and the H pulse of the second PWM signal.

In FIG. 13, the first waveform shaping circuit 25
8 and a logic circuit provided between the second waveform shaping circuit 259 and the amplifying transistor includes a first PWM signal and a second PWM signal output from the inverter drive circuit 255 when a stop signal from the overload detection circuit 260 is input. This is to stop signal output. A PWM control signal for controlling the inverter circuit 130 is formed to form an inverter drive circuit 255
The PWM signal generating circuit 250 outputs a PWM control signal using a reference sine wave of 50 Hz or 60 Hz and a triangular wave.

The reference sine wave of the PWM signal generation circuit 250 is the frequency of the voltage output from the output terminal.
It is formed in accordance with a predetermined frequency such as Hertz or 60 Hertz, adjusts the ratio between the reference sine wave voltage and the triangular wave voltage, and outputs the output voltage VD of the DC The frequency of the pulse signal used as the PWM control signal, the pulse width, and the amount of change in the pulse width are determined by the characteristics of the circuit 130 and the low-pass filter 140.

The single-phase output winding 55 of the AC generator 50 is, as shown in FIG.
Connected to 210. This smoothing circuit 210 is composed of a rectifying diode 211 and a smoothing capacitor 215, and a rectifying diode 211 is inserted between the output terminal of the single-phase output winding 55 and the smoothing capacitor 215 to form a single-phase output winding. The smoothing capacitor 215 is charged by the output voltage of 55 to form a DC voltage.

The number of the rectifying diodes 211 is not limited to one as shown in FIG. 11, but a smoothing capacitor may be charged as a full-wave rectifying bridge using four rectifying diodes. Then, the output terminal of the smoothing circuit 210 is connected to the constant voltage circuit 235, and the constant voltage circuit 235 forms a predetermined voltage for driving the control circuit.

The constant voltage circuit 235 has a negative terminal connected to the positive terminal of the DC power supply unit 120 and a positive terminal connected to the voltage limiting circuit 240, the PWM signal generating circuit 250, and the inverter drive. Connected to circuit 240. The voltage limiting circuit 240 is configured using a resistor and a comparator, and has a first reference voltage resistor 245 and a second reference voltage resistor 246 connected in series with a positive terminal of a constant voltage circuit 235 and a DC power supply. It is inserted between the positive terminal of the unit 120 and the midpoint between the first reference voltage resistor 245 and the second reference voltage resistor 246 is connected to the reference input terminal of the comparator 243. Also, the first voltage dividing resistor 248 and the second voltage dividing resistor 249 are connected in series between the + terminal of the constant voltage circuit 235 and the − terminal of the Container 248
The middle point between the first and second voltage-dividing resistors 249 is connected to the comparison input terminal of the comparator 243.

Further, the output terminal of the comparator 243 is connected to the + terminal of the constant voltage circuit 235 via the control resistor 241 and also to the gate terminal of each thyristor 111 in the DC voltage generation circuit 110. ing. When the output terminal of the comparator 243 is connected to the gate terminal of each thyristor 111, it is connected via the protection resistor 117. Therefore, in the voltage limiting circuit 240, the constant voltage circuit 2 of the control power supply circuit is used.
The constant voltage formed at 35 is divided by the first reference voltage resistor 245 and the second reference voltage resistor 246 to form a constant reference voltage, and the constant voltage reference voltage is compared. Input to the reference input terminal of the detector 243.

Further, a voltage obtained by adding the output voltage of the DC power supply unit 120 and the constant voltage formed by the constant voltage circuit 235 is divided by the first voltage dividing resistor 248 and the second voltage dividing resistor 249, and the detection voltage is obtained. And the detection voltage can be input to the comparison input terminal of the comparator 243. Therefore, the detection voltage input to the comparison input terminal fluctuates due to the voltage fluctuation of the DC power supply unit 120, and this detection voltage is connected to the first reference voltage resistor 245 and the second
When the voltage is lower than the reference voltage formed by the reference voltage resistor 246, the output of the comparator 243 is set to a positive potential.

Therefore, the gate potential of the thyristor 111 can be made higher than the cathode potential of the thyristor 111, and a gate current is supplied to each thyristor 111 via the control resistor 241 to make each thyristor 111 conductive. Will be. Therefore, when the output voltage of the three-phase output winding 51 becomes higher than the voltage of the DC power supply unit 120, power is supplied to the DC power supply unit 120, and the voltage of the DC power supply unit 120 is increased.

When the voltage of the DC power supply 120 rises and the detection voltage input to the comparator 243 becomes equal to the reference voltage, the output of the comparator 243 becomes 0, and the gate potential of each thyristor 111 becomes the cathode potential. Equal, each thyristor 11
1 becomes non-conductive. As described above, the voltage limiting circuit 240 performs charging from the AC generator 50 when the voltage formed by the DC power supply unit 120 becomes lower than a certain voltage, and stops charging when the voltage reaches the certain voltage. Can be constantly maintained at a constant voltage VD set by the voltage limiting circuit 240 at about 170 volts to 200 volts.

Then, the potential of the first output terminal 151 and the second output terminal 152 is changed by the inverter circuit 130 at a constant period of 50 Hz or 60 Hz, and the first output terminal 151 is changed.
The maximum potential difference between the voltage of the second output terminal 152 and the voltage of
A single-phase AC voltage having an average voltage of 100 volts is output by applying 41 volts. Furthermore, this portable engine generator
In 100, an overload detection circuit 260 in which a detection resistor 261 is inserted between the DC power supply unit 120 and the inverter circuit 130 is provided.

The overload detection circuit 260 includes a detection resistor 2
When the current value exceeding the rated current value is detected, a stop signal is output to the inverter drive circuit 255 in consideration of time according to the magnitude exceeding the rated value when the current value exceeds the rated current value. The arithmetic circuit unit 265 includes various circuits using a comparator, a capacitor, and a resistor. In many cases, a current twice as large as the rated current is taken into consideration in consideration of the characteristics of elements constituting a power circuit. When it flows, a stop signal is output immediately to stop the output of the first PWM signal and the second PWM signal output from the inverter drive circuit 255. When a current slightly exceeding the rated current is detected, a stop signal is output to the inverter drive circuit 255 when a time of several seconds to several minutes has been maintained.

As described above, the engine generator 100, which once rectifies the three-phase AC by the DC voltage generation circuit 110 and converts the DC voltage generated by the DC power supply unit 120 to the AC voltage again by the inverter circuit 130, comprises the AC generator 50 , Ie, the number of revolutions of the engine, to constantly generate an electric power according to the load, and to form an AC output voltage of a constant frequency and voltage.

Therefore, the engine speed is adjusted in accordance with the load fluctuation, the engine speed is increased in the case of a high load, the engine speed is lowered in the case of a low load, and the required energy is adjusted according to the load. Since it is sufficient if the power is generated from the engine, the output can be easily adjusted according to the load, and the engine generator 100 can be made efficient. When the overload state exceeds the rated output, the operation of the inverter circuit 130 is stopped instantaneously or in accordance with the elapse of a predetermined time according to the overload state, and the output voltage is set to 0 to secure the entire circuit. It is possible to operate various electrical devices loaded within a range of several kilowatts, which is a rated output, while maintaining the rated output.

Further, as such an engine generator 100, in recent years, there is a type in which the parallel operation can be performed by adjusting the output voltage value and the voltage phase of the single-phase AC power. In the engine generator 100 capable of adjusting the output voltage value and the voltage phase, the first output terminal 15 of the engine generator 100 is used.
The AC output voltage and the AC output current output from the first and second output terminals 152 are detected, and for example, the output voltage and phase of another generator performing parallel operation and the voltage of the single-phase AC power output from the engine generator 100 are detected. The PWM signal generating circuit 25 always outputs an output voltage whose value and phase are matched.
0 (for example, see Japanese Unexamined Patent Publication No.
4, JP-A-5-236658, JP-A-5-2447
No. 26).

The adjustment of the voltage value is performed not only in the case of performing the parallel operation but also in the case of performing the independent operation in order to prevent a voltage fluctuation due to the type and magnitude of the load connected to the output terminal. (See, for example,
No. 211777). In these engine generators 100, in many cases, as shown in FIG. 15, an output voltage detection circuit 340 is inserted between the first output terminal 151 and the second output terminal 152 after the low-pass filter 140, and An output current detection circuit 330 is inserted after the low-pass filter 140 to detect the voltage and current of the single-phase AC output output from the first output terminal 151 and the second output terminal 152, and control the PWM signal generation circuit 250. ing.

It should be noted that, similarly to the engine generator 100 shown in FIG. 11, the engine generator 100 also includes a control power source in which the single-phase output winding 55 of the AC generator 50 is constituted by a smoothing circuit 210 and a constant voltage circuit 235. The output voltage of the single-phase output winding 55 is smoothed by a smoothing circuit 210, and a control voltage Vcc of a predetermined voltage is formed by a constant voltage circuit 235. However, the control power supply unit 201 may form a + Vcc voltage and a -Vcc voltage as control voltages in accordance with the elements constituting the control circuit.

The output terminal of the three-phase output winding 51 is connected to a DC voltage generating circuit 110 which is a rectifier bridge circuit using a thyristor and a rectifier diode, and rectifies the output voltage of the three-phase output winding 51. A DC voltage is formed by charging a large-capacity capacitor serving as the DC power supply unit 120, and this DC voltage is input to the inverter circuit 130 to form a single-phase AC voltage, similarly to the above-described prior art.

The PWM signal generation circuit 250 includes a sine wave generation circuit 270 for forming a reference sine wave, a triangular wave generation circuit 281 and a PWM control signal generation circuit 285 for forming a PWM control signal. The wave generation circuit 270 forms an accurate 50 Hz or 60 Hz reference sine wave,
The triangular wave generating circuit 281 forms a high frequency triangular wave of about several kilohertz to several tens of kilohertz, and the PWM control signal generating circuit 285 combines a reference sine wave and a triangular wave to form a pulse train whose pulse width changes sequentially. It forms a signal.

Further, the sine wave generation circuit 270 outputs an oscillation circuit 271 for outputting a high frequency signal of several megahertz to several tens of megahertz, and a clock signal of about 10 kilohertz by dividing the high frequency signal output by the oscillation circuit 271. The dividing circuit 273 forms a number of different potentials by means of a multi-stage voltage dividing resistor, and sequentially selects different potentials by a multiplexer operated by a clock signal to form a stepped sine wave of 50 Hz or 60 Hz. Pseudo sine wave forming circuit
275, and a voltage adjusting circuit 277 for adjusting the peak voltage of the stepped sine wave output from the pseudo sine wave forming circuit 275, and a low-pass filter for forming a smooth sine wave from the stepped sine wave
279.

The voltage detection signal output from the output voltage detection circuit 340 is input to a rectangular wave forming circuit 291 to form a rectangular wave signal having a zero cross point of the AC output voltage as a rising edge and a falling edge, The zero-cross signal converted into the rectangular wave signal is input to the start timing circuit 293 and the phase comparison circuit 297. The start timing circuit 293 releases the pseudo sine wave forming circuit 275 in the sine wave generating circuit 270 so that the pseudo sine wave forming circuit 275 outputs a pseudo sine wave.

Then, when the pseudo sine wave forming circuit 275 is in the reset state and the reference sine wave is not output from the sine wave generating circuit 270, that is, when the inverter circuit 130 is not operating, the output voltage detecting circuit 340 is set to the first state. When detecting a voltage change between the output terminal 151 and the second output terminal 152, the start timing circuit 293 releases the reset of the pseudo sine wave forming circuit 275 in accordance with the zero cross signal from the rectangular wave forming circuit 291 and generates a sine wave. The phase of the reference sine wave output from the circuit 270 matches the phase of the voltage generated between the first output terminal 151 and the second output terminal 152.

When starting the operation of the pseudo sine wave forming circuit 275, the pseudo sine wave forming circuit 275 may be operated even when the zero cross signal is not input to the start timing circuit 293 within a predetermined time.
And the output of the reference sine wave from the sine wave generation circuit 270 is started. Then, the output current detection circuit 330
Is input to a rectangular wave forming circuit 295, an overload detecting circuit 269, and a limit value detecting circuit 299, and the rectangular wave forming circuit 295 detects a zero-cross signal in accordance with the phase of the output current to detect an overload. The circuit 269 generates a stop signal when the rated current is exceeded, and the limit value detection circuit 299 generates a voltage adjustment signal when the current value is equal to or less than the rated current and exceeds a predetermined lower limit value and upper limit value range. And

The rectangular wave forming circuit 295 forms a rectangular wave signal having the zero cross point of the AC output current as a rising edge and a falling edge based on the current detection signal output from the output current detection circuit 330. The wave signal is input to the phase comparison circuit 297 as a zero-cross signal. This phase comparison circuit 297 compares the phase of the output current with the phase of the output voltage based on the zero-cross signal based on the current detection signal and the zero-cross signal based on the voltage detection signal, and determines whether the current phase is later than the voltage phase. Outputs the added signal as a phase adjustment signal to the frequency divider 273, and
If the current phase is more advanced than the voltage phase, the subtraction signal is output to the frequency divider 273 as a phase adjustment signal.

In the frequency dividing circuit 273 of the sine wave generating circuit 270, when the high frequency signal is frequency-divided to form a clock signal of several kilohertz to several tens of kilohertz, an additional signal is input from the phase comparing circuit 297. One pulse is added for every several hundred pulses of the clock signal. When a subtraction signal is input from the phase comparison circuit 297, a clock signal is formed by thinning out one pulse every several hundred pulses of the clock signal.

As described above, when the current phase lags behind the voltage phase, the pulse of the clock signal is increased to slightly advance the phase of the pseudo sine wave and thus the reference sine wave, and the current phase leads the voltage phase. In this case, the phase of the reference sine wave is slightly delayed by thinning out the pulses of the clock signal, the phase of the PWM control signal is adjusted, and the phase of the single-phase AC voltage output from the engine generator 100 is adjusted.

The first output terminal 151 and the second output terminal 152
In the case where the PWM control signal is formed by the PWM signal generation circuit 250 in accordance with the voltage value and the current phase of the output voltage output from the inverter drive circuit 255, as shown in FIG. 258 and an inverter drive circuit 255 having a second waveform shaping circuit 259;
The first PWM signal and the second PWM having a dead time between the H pulse of the PWM signal and the H pulse of the second PWM signal.
It may form a signal.

The overload detection circuit 269, to which the current detection signal output from the output current detection circuit 330 is input, is based on the current detection signal output from the output current detection circuit 330. The stop signal is output immediately, and when the rated current is slightly exceeded, time integration is performed and the stop signal is output after the required time. And
This stop signal is input to the voltage control circuit 240 and the inverter drive circuit 255, shuts off the gate current output from the voltage control circuit 240 to stop the operation of the DC voltage generation circuit 110, and outputs the signal from the inverter drive circuit 255. The output of the first PWM signal and the second PWM signal is stopped to stop the operation of the inverter circuit 130.

Further, a limit value detection circuit 299 to which a current detection signal output from the output current detection circuit 330 is input is a circuit in which a current upper limit value and a current lower limit value are set.
When the current value of the current detection signal becomes equal to or less than the current lower limit value, the peak value (amplitude) of the reference sine wave is reduced or increased so that the output voltage which is the voltage between the first output terminal 151 and the second output terminal 152 is slightly increased. Voltage adjustment circuit to increase the voltage adjustment signal
Output to 277. When the current value of the current detection signal exceeds the current upper limit value, the first output terminal 151 and the second output terminal 1
A voltage adjustment signal for increasing or decreasing the peak value of the reference sine wave so as to slightly reduce the output voltage which is a voltage between 52 is output to the voltage adjustment circuit 277.

As described above, since the current upper limit value and the current lower limit value are set within the range of the rated current and the output voltage can be finely adjusted, the load sharing can be performed while the generators are operating in parallel. If the load is small, the output voltage is slightly increased to increase the output current, and if the supply current to the load is near the limit of the rated current, the output voltage is slightly decreased to load each engine generator 100. Is effectively shared.

When the parallel operation is not performed, that is, when the engine generator 100 is used alone by the single operation, the output voltage varies depending on the capacity and type of the load. In some cases, the amplification factor of the voltage adjusting circuit 277 or the voltage of the triangular wave output from the triangular wave generating circuit 281 is adjusted based on the voltage to stabilize the voltage value of the single-phase AC voltage that is the output voltage.

As described above, the engine generator 100 equipped with an engine using the inverter circuit 130 can efficiently generate and output the same 100-volt single-phase AC power as the commercial power supply. It has been used as a power source for various general electric devices.

[0045]

When a DC voltage is converted into an AC voltage by an inverter circuit forming a bridge using switch elements, it is preferable to provide a dead time in which the series switch elements are not simultaneously turned on. . In order to perform efficient orthogonal transformation, it is necessary to adjust the dead time according to the circuit characteristics.
Adjusting the dead time by changing the pulse widths of the first PWM signal and the second PWM signal, which are control signals, by a logic circuit or the like requires an appropriate dead time in consideration of variation in characteristics of components constituting the circuit and temperature change characteristics. It was difficult to set the time.

Therefore, when a dead time is provided,
In order to protect the circuit by providing a dead time slightly longer than the response time of the switch element, and to control the inverter circuit without providing a dead time when the response characteristic of the switch element is good. However, when a dead time longer than the response time of the switch element is provided, there is a disadvantage that the output power of the single-phase AC voltage is reduced. When no dead time is provided, the single-phase AC voltage is reduced with respect to the engine output. There is a drawback that the conversion efficiency to the is reduced.

According to the present invention, a microcomputer controls an inverter circuit based on a PWM reference value.
When forming control signals such as a PWM signal and a second PWM signal, the engine generator includes a control unit that forms pulses of the first PWM signal and the second PWM signal in consideration of dead time data, and the operation state of the inverter circuit is changed. The engine generator controls the inverter circuit by the combined control signal.

[0048]

According to the present invention, an AC voltage generated by an AC generator (50) driven by an engine is rectified by a DC voltage generating circuit (110) and charged to a DC power supply section (120). An engine generator (100) that outputs a DC voltage formed by performing an inverter circuit (130) as an AC voltage of a predetermined frequency from an output terminal (151, 152), wherein the inverter circuit (130) is a bridge circuit using a switch element. And a control unit (310) for outputting a control signal for controlling the on / off of the switch element of the bridge circuit.The control signal further includes the conduction time data and the dead time stored in the control unit (310). An engine generator (100) formed and output based on the data.

As described above, since the control unit (310) for forming a control signal based on the conduction time data and the dead time data is provided, a control signal having an arbitrary dead time can be easily provided based on the dead time data. Can be.
Further, the present invention has a rewritable storage area in the control unit (310), and dead time data for preventing a short circuit of the bridge circuit can be inputted from outside the engine generator (100). Machine (100).

As described above, if the dead time data can be externally input, the dead time data can be easily changed. According to the present invention, there is provided a control unit storing a plurality of dead time data.
It is preferable that the engine generator (100) include (310) and the value of the dead time data is determined by the output voltage of the DC power supply unit (120).

As described above, if the value of the dead time data is selected and determined from the plurality of dead time data based on the output voltage of the DC power supply unit (120), the voltage applied to the switch element in the inverter circuit (130) is reduced. The dead time can be changed accordingly. Also, as the present invention,
It is preferable that the value of the dead time data is determined by the temperature of the engine generator (100).

As described above, if the dead time data is changed and determined according to the temperature, the dead time can be changed according to the temperature characteristics of the switch element, and the dead time can be set according to the operating state of the switch element. .

[0053]

BEST MODE FOR CARRYING OUT THE INVENTION A portable engine generator according to the present invention rotates an AC generator by an engine having an output of several kilowatts to about 10 kilowatts, and once converts the AC output voltage of the AC generator to DC. A portable engine that forms a single-phase AC output voltage by being converted into AC by an inverter circuit, and is frequently moved and used at the place of use, or is sometimes brought into the place of use and operated as a fixed installation state It is a generator.

This engine generator has an AC generator 50 for rotating a rotor by the engine, and as shown in FIG. 1, an electric power mainly including a DC voltage generation circuit 110, a DC power supply section 120, and an inverter circuit 130. Circuit 101, the power circuit 101
A microcomputer which is a central control unit 310 as a control unit that sets the frequency of an output voltage output from the output terminal of the unit and controls the entire engine generator 100 based on a detection signal from a detection circuit provided in each unit. And a control power supply unit for generating operating power for the control unit and the detection circuit.
The engine generator 100 has 201.

The central control means 310 serving as the control section
Sets the frequency of the output voltage to a predetermined constant frequency such as 50 Hz or 60 Hz by the setting switch 318,
The operation of the inverter circuit 130 is controlled based on the detection signals from the DC voltage detection circuit 320, the output current detection circuit 330, and the output voltage detection circuit 340 provided in the power circuit 101, and further, the detection signal from the rotation speed detection circuit 319. And throttle control mechanism 3
The opening / closing control of the engine throttle is also performed based on the opening signal from 15.

The setting switch 318 is capable of adjusting the output voltage in addition to setting the frequency. The AC generator 50 of the engine generator 100 has a three-phase output winding 51 and a single-phase output winding 55, the three-phase output winding 51 is controlled by the power circuit 101, and the single-phase output winding 55 is controlled by the single-phase output winding 55. Connected to power supply unit 201.

The output terminal of the three-phase output winding 51 is connected to a DC voltage generating circuit 110 by a rectifying bridge using three rectifying diodes 115 and three thyristors 111, as shown in FIG. Connect and gate voltage generator 1
60 is also connected. This DC voltage generating circuit 110 connects the connection point between the cathode of each rectifier diode 115 and the anode of each thyristor 111 to each output terminal of the three-phase output winding 51, and collects the anodes of each rectifier diode 115. To the negative terminal of the DC power supply unit 120 and the inverter circuit 130, and collectively connect the cathodes of the thyristors 111 to the DC power supply unit 1.
It is connected to the + terminal of 20 and the inverter circuit 130.

The gate voltage generating circuit 160 connected to the output terminal of the three-phase output winding 51 is formed using a rectifying diode, a limiting resistor, a power supply capacitor and a zener diode. That is, each output terminal of the three-phase output winding 51 is connected to the anode of the rectifying diode 161 and the cathode of each rectifying diode 161 is shared.
A negative terminal of the power supply capacitor 165 is connected to the + terminal of the DC power supply unit 120 via a 63, and a zener diode 167 is connected in parallel with the power supply capacitor 165.

Therefore, the gate voltage generation circuit 160
A voltage higher than the voltage of the + terminal of the DC power supply unit 120 by the specified voltage of the Zener diode 167 can be formed and output. The output terminal of the gate voltage generation circuit 160 is connected to each gate terminal of each thyristor 111 in the DC voltage generation circuit 110 via the thyristor control circuit 170.

This thyristor control circuit 170 comprises a switching transistor 173, a switch control resistor 171 and a photocoupler 175. That is, the collector of the PNP transistor serving as the switching transistor 173 is connected to the output terminal of the gate voltage generating circuit 160, and the emitter of the switching transistor 173 is connected to the gate terminal of each thyristor 111. The thyristor 111
When connecting to the gate terminal, the protective resistor 117 is used to connect to the gate terminal.

The base of the switching transistor 173 is connected to the output terminal of the gate voltage generating circuit 160 via the switch control resistor 171, and the switch control resistor 1
The midpoint of 71 is connected to the + terminal of the DC power supply unit 120 via the phototransistor 176 of the photocoupler 175. still,
The phototransistor 176 of the photocoupler 175 has a collector connected to the middle point of the switch control resistor 171, an emitter connected to the + terminal of the DC power supply unit 120, and a light emitting diode 177 of the photocoupler 175 having the anode connected to the control power supply. The cathode of the light emitting diode 177 is connected to the output terminal of the second control voltage Vcc in the unit 201, and the constant voltage detection circuit 180 and the stop circuit 36
0, connected to overcurrent detection circuit 350.

Therefore, the thyristor control circuit 170
When the light emitting diode 177 of the photocoupler 175 turns on,
The phototransistor 176 becomes conductive, the midpoint potential of the switch control resistor 171 drops to the + terminal voltage of the DC power supply unit 120, and the switching transistor 173 becomes nonconductive. When the light-emitting diode 177 does not light, the switching transistor 173 is turned on to supply the output current of the gate voltage generation circuit 160 to each thyristor 111 as the gate current of the thyristor 111. Each thyristor 111 of the generation circuit 110 is turned on.

Therefore, the output power of the three-phase output winding 51 can be supplied to the DC power supply unit 120 connected to both output terminals of the DC voltage generation circuit 110. Also, DC voltage generation circuit
The inverter circuit 130 connected to both output terminals of the 110 is a bridge circuit with a power transistor and a smoothing capacitor.
173. The inverter circuit 130 connects a first transistor 131 and a third transistor 133 as switching elements in series to the DC power supply unit 120, and connects a second transistor 132 and a fourth transistor 134 as switching elements in series. The first transistor 131 and the third transistor 133 are connected to the first output terminal 151 via the low-pass filter 140, and the middle point between the second transistor 132 and the fourth transistor 134 is connected to the low-pass filter. By connecting to the second output terminal 152 via the filter 140, an H-bridge is formed between the + side and the − side of the DC power supply unit 120 using four switch elements.

Although the inverter circuit 130 is a bridge circuit using four power transistors in the drawing, the first transistor 131 serving as a switching element is formed by combining a plurality of transistors to have a predetermined breakdown voltage and capacity. In some cases, the second transistor 132 to the fourth transistor 134 may have a predetermined breakdown voltage and a predetermined capacitance by combining a plurality of transistors.

The single-phase output winding 55 of the AC generator 50 is connected to the smoothing circuit 210 of the control power supply unit 201, as shown in FIG. The smoothing circuit 210 includes four rectifying diodes 2
The bridge rectifier circuit 11 performs full-wave rectification to charge the smoothing capacitor 215. The control power supply unit 201 has a first constant voltage circuit 221 and a second constant voltage circuit 225 and a regulator 230 in addition to the smoothing circuit 210, and the output voltage of the smoothing circuit 210 is adjusted to 15 volts by the first constant voltage circuit 221. And the first reverse current blocking diode 233
To the regulator 230 through the DC power supply unit 120
Is set to a constant voltage of about 12 volts by the second constant voltage circuit 225, and the second reverse current blocking diode 234
Is applied to the regulator 230.

In the regulator 230, a first control voltage Vss of about 10 volts and a second control voltage Vcc of about 5 volts are formed, and the first control voltage Vss is used to drive a throttle control motor of an engine described later. And the second control voltage Vcc is supplied to the central control means 310 and other control circuit elements. It should be noted that the control power supply unit 201 normally outputs the smoothing circuit 21 from the AC voltage output from the single-phase output winding 55.
The 0 and the DC voltage formed by the first constant voltage circuit 221 are supplied to the regulator 230, and the regulator 230 forms the first control voltage Vss and the second control voltage Vcc and supplies them to each circuit element. Then, when a failure such as a disconnection occurs in the single-phase output winding 55 or the like, if the DC power supply unit 120 is operating, power is supplied to the regulator 230 by the second constant voltage circuit 225,
The first control voltage Vss and the second control voltage Vcc are output from the regulator 230 to maintain the operation of the engine generator 100.

Further, a switch circuit for detecting and switching the output voltage of the first constant voltage circuit 221 may be disposed on the input side of the regulator 230 instead of the first backflow prevention diode 233 and the second backflow prevention diode 234. is there. In this case, the output voltage of the first constant voltage circuit 221 and the second constant voltage circuit 225
The power from the first constant voltage circuit 221 is normally supplied to the regulator 230 while the output voltage of the second constant voltage circuit 221 is stopped, and the output voltage from the second constant voltage circuit 225 is stopped when the output of the first constant voltage circuit 221 stops. The switch circuit may be switched so as to supply the voltage to the regulator 230. Further, the AC generator 50 having no single-phase output winding 55 is used, and the smoothing circuit 210 and the first
In some cases, the constant voltage circuit 221 is omitted, the voltage of the DC power supply unit 120 is reduced by the second constant voltage circuit 225, and the power of the DC power supply unit 120 is always supplied to the regulator 230 to form a control voltage.

As shown in FIG. 3, the constant voltage detection circuit 180 for controlling the voltage of the DC power supply 120 uses a resistor, a Zener diode, and a switching transistor.
The voltage of the DC power supply unit 120 is divided by the voltage dividing resistors 181 and 182 in which two resistors are connected in series, and the midpoint potential of the voltage dividing resistors 181 and 182 is further reduced by the Zener diode 183 and the detection resistor 184 to detect the voltage. Schmitt circuit 1 for the potential of resistor 184
85, which controls the conduction of the switching transistor 187.

Further, the switching transistor 187
Is connected in series with the light-emitting diode 177 of the photocoupler 175 in the thyristor control circuit 170, and controls the lighting of the light-emitting diode 177 by applying a second control voltage Vcc to the series-connected light-emitting diode 177 and cutting off the conduction of the switching transistor 187. . Therefore, this constant voltage detection circuit 180
Is the detection resistor 1 when the output voltage of the DC power supply 120 rises.
The detection potential of 84 rises and the switching transistor 187
Is turned on to light the light emitting diode 177. For this reason, the thyristor control circuit 170 stops outputting the conduction signal to the DC voltage generation circuit 110, puts each thyristor 111 of the DC voltage generation circuit 110 into a non-conduction state, and outputs the power from the AC generator 50 to the DC power supply unit 120. Stop supply.

When the voltage of the DC power supply unit 120 drops, the switching transistor 187 is turned off, and the thyristor control circuit 170 outputs a conduction signal to turn on each thyristor 111 of the DC voltage generation circuit 110. In this manner, the potential of the DC power supply unit 120 can be always kept constant by the constant voltage detection circuit 180.

The DC voltage detecting circuit 320 connects the voltage dividing resistor 325 so as to be inserted between both terminals of the DC power supply unit 120. The output of the DC power supply unit 120 is controlled by the voltage dividing resistor 325. The voltage is divided and the output voltage value of the DC power supply unit 120 is input to the central control means 310 as a DC voltage signal. An output voltage detection circuit 340 inserted between the inverter circuit 130 and the low-pass filter 140 detects the voltage by dividing the first output voltage and the second output voltage of the inverter circuit 130 by a voltage-dividing resistor. A first detection voltage obtained by dividing the first output voltage by the voltage dividing resistors 341 and 342, and a second detection voltage obtained by dividing the second output voltage by the voltage dividing resistors 343 and 344, respectively. The output voltage signal is input to the central control unit 310 via the low-pass filters 347 and 348 for detection.

When the output voltage signal output from the output voltage detection circuit 340 is input to the central control means 310, the first output voltage signal and the second output voltage signal which are analog signals are input to the central control means 310. At the same time, the zero cross signal from the square wave forming circuit 317 is also input to the central control means 310. The rectangular wave forming circuit 317 forms a rectangular wave based on a difference voltage between the first output voltage and the second output voltage forming a sine wave, and generates a square wave based on the difference between the first output voltage and the second output voltage forming a sine wave. The zero cross point in the difference voltage is defined as the edge of the rectangular wave, and a zero cross signal indicating the timing of the zero cross point in the output voltage output from the engine generator 100 is input to the central control means 310.

Further, the output current detection circuit 330 detects the current flowing from the inverter circuit 130 to the low-pass filter 140 with the detection resistor 331 and uses the detection low-pass filter 335 to remove the harmonic component from the output current signal. It is input to the central control means 310 and the overcurrent detection circuit 350. The output current detection circuit 330 may be provided on the input side of the inverter circuit 130. When the output current detection circuit 330 is provided on the input side of the inverter circuit 130,
Output current detection circuit 330 between the side terminal and the inverter circuit 130.
Is provided, it becomes easy to lower the absolute voltage of the output current signal output from the output current detection circuit 330.

As the output current detection circuit 330, not only the case where the detection resistor 331 is used, but also a current detector using an induction coil may be used. The overcurrent detection circuit 350 includes resistors 351 and 352, a comparator 355, and a switching transistor 357, and applies the second control voltage Vcc formed by the control power supply unit 201 to the reference voltage dividing resistors 351 and 352.
The output current detection circuit 33
When the potential of the output current signal output by 0 becomes higher than the reference voltage, the switching transistor 357 is turned on.

Further, the switching transistor 357
Has an emitter grounded and a collector connected to the cathode of the light emitting diode 177 in the photocoupler 175. Therefore, when the switching transistor 357 is turned on, the overcurrent detection circuit 350
To stop the output of the conduction signal. It should be noted that the central control means 310 serving as a control unit includes a DC voltage signal from the DC voltage detection circuit 320, an output current signal from the output current detection circuit 330, an output voltage signal from the output voltage detection circuit 340, The zero-cross signal from the rectangular wave forming circuit 317 based on the voltage signal is input as a detection signal, and the three-phase output winding 51
The detection signal of the frequency of the output voltage output from the motor is also input as a rotation speed signal from the rotation speed detection circuit 319, and the cathode potential of the light emitting diode 177 is also input as a conductivity detection signal. Is also input, but the opening signal from the throttle control mechanism 315 may be omitted.

The central control means 310 to which these detection signals are input operates as shown in FIG.
The first PWM signal and the second PWM signal based on the reference value are represented by P
In addition to the PWM signal generation unit 441 to be output to the WM driver 311, a PWM signal is generated by judging whether control is started alone or in parallel at the start of control based on the output voltage signal from the output voltage detection circuit 340 and the zero-cross signal from the rectangular wave formation circuit 317. Part 441
Islanding operation control unit 435 and synchronous operation control unit 437,
Further, an output frequency setting unit 415 for setting the frequency of the single-phase AC voltage based on a signal from the setting switch 318 and a setting switch 3
An output voltage setting unit 417 that adjusts and sets the output voltage of the single-phase AC voltage based on the signal from the signal output from the output voltage detection circuit 340 and a single voltage output from the first output terminal 151 and the second output terminal 152 based on the output voltage signal from the output voltage detection circuit 340 A voltage waveform monitoring unit 433 that monitors the phase AC voltage, and an engine rotation speed detection unit that determines the engine rotation speed based on the rotation speed signal from the rotation speed detection circuit 319.
421, the output current signal, the rotation speed signal, and the throttle driver 3 based on the opening signal from the throttle control mechanism 315.
Throttle opening control unit 42 that outputs a rotation control signal to 13
3, and a circuit protection unit 431 that outputs a stop control signal to the stop circuit 360 based on an output current signal from the output current detection circuit 330 or a DC voltage signal from the DC voltage detection circuit 230, and a light emitting diode in the thyristor control circuit 170. A conductivity detection unit 419 for detecting the conductivity of the thyristor 111 in the DC voltage generation circuit 110 based on the cathode potential of 177, and furthermore, the engine generator 100 according to the control operation state of the central control means 310.
And a display control unit 425 that outputs a signal for causing the operation state display unit 427 to display the operation status of the operation state.

Although not shown, the microcomputer serving as the central control means 310, which is a control unit, has a crystal oscillator of ten and several megahertz and operates using the output of the crystal oscillator as a reference clock. A read-only memory in which a control program, a control data table, and the like are recorded, a random access memory for performing arithmetic processing, and a frequency dividing circuit that divides a reference clock to form a required clock signal. Things.
An analog-to-digital converter 411 for converting an input analog signal into a digital signal is also provided.

Then, the PWM signal generation section 441 outputs the PWM
It has a reference table and a dead time table.
PW as conduction time data stored in the M reference table
A first PWM signal and a second PWM signal are formed based on the M reference value, and the first PWM signal and the second PWM signal are defined as P
The short circuit of the inverter circuit 130 forming a bridge circuit is prevented by the dead time data output to the WM driver 311 and stored in the dead time table, and the first to fourth transistors 131 to 134 in the inverter circuit 130 are turned on. Control the interruption.

This PWM reference table contains a large number of PWMs.
It is a table that stores reference values, and each PWM reference value is:
The numerical value is about one hundred to several hundreds corresponding to the value of the curve forming one cycle of the sine wave curve. Then, the PWM signal generation unit 441 of the central control unit 310 outputs the PWM
PWM reference values are sequentially read from the M reference table and
M control signal or the first PWM signal and the second PWM signal, and the PWM control signal or the first PWM signal and the second PWM signal
The PWM signal is output to the PWM driver 311.

This PWM control signal is conduction time data in which the maximum value is less than +127 and the minimum value is more than -127 when the head value of the PWM reference table is 0, One hundred to several hundred values as values forming a sine wave curve are stored, and one half of one clock time in a read clock for reading each PWM reference value is stored.
A value corresponding to time is added to each read PWM reference value,
When the PWM reference value is 0, a pulse signal having a duty ratio of 50% is formed. For this reason, PW
Each pulse of the M control signal corresponds to each PW which is conduction time data.
Based on the M reference value, as shown in (1) of FIG. 5, the duty ratio is sequentially changed in accordance with the sine wave shape, and the duty ratio ranges from several tens of percent around 50% to several tens of percent before 100%. The pulse signal train forms a reference sine wave that changes sequentially with a value in the range.

The frequency of the output voltage ranges from 100 to several hundreds of Ps forming one cycle of the single-phase AC voltage recorded in the PWM reference table of the PWM signal generator 441.
Depending on whether the WM reference value is a read clock Kr that can be read in 20 milliseconds or a read clock Kr that can read one period of the PWM reference value in 16.66 milliseconds, the engine power generation can be performed. The frequency of the single-phase AC voltage output from the device 100 is determined.

The read clock Kr at several kilohertz to several tens of kilohertz is obtained by dividing the frequency of a reference clock of tens of megahertz, and the PWM reference value is eight.
The time width of the read clock Kr is set to 2 by the bit data.
It is divided into 56 equal parts. Further, based on the PWM reference value which is the conduction time data, the first PWM signal and the second PWM signal are used.
In forming the PWM signal, as shown in FIG.
First, in the case of the n-th PWM reference value Tn, the PWM control signal is set to one-half of one clock time in the read clock Kr so that the PWM control signal is based on the PWM reference value T.
The value of “1” in the WM reference value T is set to a pulse having a time width corresponding to the n-th PWM reference value Tn in correspondence with several pulses of the reference clock. Then, the first PWM signal corresponds to the value t of the dead time data with respect to the PWM control signal.
The second PWM signal is formed from the falling timing of the first PWM signal to the value t of the dead time data from the falling timing of the first PWM signal.
Is started up with a delay of the number of reference clock pulses corresponding to.

The dead time data for determining the time width of the dead time depends on the response characteristics of the first to fourth transistors 131 to 134 serving as the switching elements, the frequency of the output voltage and the output voltage value. Is set to 100 volts, 120 volts, 230 volts, and the like, and the standard setting values are stored. For example, when an output voltage of 100 volts and 50 hertz is formed, an element constituting a circuit is stored. In order to form a non-conduction time for preventing short circuit of several hundred nanoseconds to 1 microsecond in accordance with the characteristics of the above, dead time values of five to ten and several clocks in the reference clock are stored.

Therefore, based on the PWM reference value which is the conduction time data and the value of the dead time data which determines the dead time, the PWM signal generating section 441 has several kilohertz to several tens kilohertz having a dead time such as several hundred nanoseconds. A first PWM signal and a second PWM signal are formed as the control pulse signals of the above, and the first PWM signal and the second PWM signal are output to the PWM driver 311 and the PWM driver 311
Then, the first PWM signal and the second PWM signal are current-amplified and output to the inverter circuit 130, so that the conduction control of the first transistor 131 to the fourth transistor 134, which are switch elements, can be performed.

As described above, the first PWM signal and the second PWM signal which are the control signals by dividing the frequency of the high-frequency reference clock based on the conduction time data and the dead time data are used as the PWM signal generator 441 of the central control means 310. If formed with
The first PWM signal and the second PWM signal having the dead time corresponding to the value of the dead time data can be accurately formed, and the orthogonal transform by the inverter circuit 130 can be performed efficiently.

The dead time data sets a reference value according to the voltage value and frequency of the output voltage in accordance with the circuit characteristics, and as shown in FIG.
The dead time data t0 corresponding to the preset DC voltage HV such as 170 volts is stored, and the value is slightly smaller than the value of the reference dead time data t0. In the dead time table, a plurality of values that are smaller than the value of the dead time data t0 are stored in the dead time table, and the appropriate dead time data is converted to the dead time according to the value of the DC voltage HV output from the DC power supply unit 120. May choose from a table.

As described above, by using the dead time table for storing a plurality of dead time data and selectively determining the value of the dead time data based on the value of the DC voltage signal from the DC voltage detection circuit 320, When the output voltage of the DC power supply unit 120 is set to 160 volts to 170 volts so that the output voltage from the generator 100 is set to 100 volts, or the DC power supply unit Output voltage of 20
When the voltage is set to about 0 volt, the output voltage of the DC power supply unit 120 is set to 300
For example, when the voltage is set to about volt, it can be used for the engine generator 100 having a set voltage according to various output voltages.

Further, the value of the dead time data may be changed depending on the temperature of the engine generator 100, particularly, the temperature of the inverter circuit 130. In this case, FIG.
As shown in (B) of FIG.
Is stored as a reference value t0 of the dead time data, and when the temperature exceeds about 60 degrees or 80 degrees, the value of the dead time data is sequentially increased according to the temperature rise. Is to increase the value of.

Thus, the temperature of the engine generator 100,
In particular, if the value of the dead time data is changed in accordance with the rise in the temperature of the inverter circuit 130, when the temperature of a switch element or the like rises at a normal operating temperature, the dead time is reduced according to the change in the reaction speed due to the temperature characteristics of the element. While making it a little longer, while preventing a short circuit in the inverter circuit 130,
Effectively reduces the output voltage of DC power supply unit 120 with low-pass filter 1.
The signal can be output to the first output terminal 151 and the second output terminal 152 via 40.

When the value of the dead time data is changed, it is not limited to selecting and extracting predetermined dead time data from a dead time table storing a large number of dead time data. Is stored, the DC voltage value and the temperature of the circuit are detected, and the dead time data value is determined by changing the dead time data value by multiplying the dead time data value by a variable based on the detected value. Sometimes.

When the dead time data is changed depending on the temperature, as shown in FIG.
A thermistor 377 or the like 5 is provided near the inverter circuit 130 or the like, and a temperature signal is input to the central control means 310. The dead time data is not limited to the case where the data is stored in an internal memory forming a PWM reference table or the like of the PWM signal generation unit 441 in the central control unit 310. The dead time data may be stored in a nonvolatile memory such as an EEPROM or a flash memory. As a control unit added to the central control means 310 as 380, a dead time table is formed in the external storage means 380, and a terminal 385 for writing data to the external storage means 380 is provided in the engine generator 100. It is something to keep.

When the external storage means 380 is added,
Dead time data to be stored in the dead time table can be externally input and appropriate dead time data corresponding to each engine generator 100 can be stored. The data table formed in the external storage means 380 is not limited to the dead time table, but forms a dead time table and a PWM reference table, and includes a conduction time together with dead time data for preventing a short circuit of the bridge circuit. The PWM reference value which is data is also externally connected.
In some cases, writing to the external storage means 380 via the 385 may be enabled.

In this case, according to the characteristics of the engine generator 100, the PWM reference value can be easily changed together with the dead time data. The voltage waveform monitoring unit 433 of the central control unit 310 has an output voltage value table that stores a number of voltage table values corresponding to the respective PWM reference values, and a timing for reading out the PWM reference value from the PWM reference table. The voltage table value is read from the output voltage value table in accordance with the above, the read voltage table value is compared with the value of the output voltage input from the output voltage detection circuit 340, the PWM reference value is corrected, and the PWM signal generation unit First PWM signal and second PWM signal output from 441
The pulse width of each pulse signal forming the signal is corrected to adjust the output voltage.

Further, a start switch (not shown) is operated to output the first PWM signal and the second PWM signal from the PWM signal generator 441, and to output the single-phase AC voltage from the first output terminal 151 and the second output terminal 152. When starting, the central control means 310 determines whether or not the zero-cross signal from the rectangular wave forming circuit 317 has been input, and when the zero-cross signal has not been input, starts the operation of the isolated operation control unit 435. It is assumed.

When the operation of the isolated operation control section 435 is started, the PWM signal generation section 441 of the central control means 310 is started.
Is an average output voltage between the first output terminal 151 and the second output terminal 152, such as 100 volts set by the setting switch 318, and a frequency of 50 Hz or 6 Hz.
A first PWM signal forming a voltage at 0 Hz and a second PWM signal;
A PWM signal is output based on a PWM reference value.

The adjustment of the output voltage is performed by multiplying or adding the correction value to the PWM reference value recorded in the PWM reference table to form a corrected reference value, and based on the corrected reference value, the first PWM signal and the first PWM signal. This determines the width of each pulse of the pulse signal used as the second PWM signal. And this PWM
The independent operation control unit 435 reads a correction value for calculating a correction reference value from the reference value from the output voltage setting unit 417, and transfers this correction value to the PWM signal generation unit 441.

Further, the PWM signal generator 441 sends the first PWM
After the M signal and the second PWM signal are output, the output voltage waveform monitoring unit 433 monitors the peak voltage and the sine wave distortion based on the output voltage signal from the output voltage detection circuit 340,
When the peak voltage fluctuates from the set value, a correction value for correcting a difference from the set voltage is output from the output voltage waveform monitoring unit 433 to the PW
The M signal generation unit 441 reads the data. Also, when the distortion of the sine wave continues, the correction value is output to the PWM signal generation unit.
A single-phase AC voltage, which is a voltage read and set by the 441 and is a smooth sine wave, is output.

The waveform of the single-phase AC voltage is distorted depending on the capacity and type of the load.
By correcting the M control signal, control is performed such that the output voltage always has a predetermined sine wave shape. In this correction, a correction value for correcting the PWM reference value is stored in association with each PWM reference value based on the internal impedance of the power circuit 101, the output current value, and the output current value,
When the PWM signal is generated next time by the PWM signal generator 441 based on the reference value, the correction is performed by adding or subtracting the correction value corresponding to each PWM reference value. Then, a PWM control signal is formed based on the corrected PWM reference value.

The first PWM signal and the second PWM signal corresponding to the PWM control signal having a duty ratio of 50%
The WM signal is output from the central control means 310, and a minute time until the output voltage value signal indicating the output voltage of 0 is input to the central control means 310 by the pulse signal is preset in advance by the circuit characteristics of the inverter circuit 130 and the like. And comparing the voltage table value with the detected output voltage value,
This minute time difference is corrected based on the zero-cross signal input from the rectangular wave forming circuit 317, and the relationship between the first PWM signal and the second PWM signal and the output voltages output to the first output terminal 151 and the second output terminal 152 is correctly determined. You may need to adjust it.

Further, the PWM signal generation section 441 sends the first PWM
When starting the output of the signal and the second PWM signal, when the zero cross signal from the rectangular wave forming circuit 317 is input to the central control means 310 before the output of the first PWM signal and the second PWM signal is started, the central control means 310 Then, the operation of the synchronous operation control unit 437 is started. The synchronous operation control unit 437 determines whether the frequency of the voltage generated between the first output terminal 151 and the second output terminal 152 matches the frequency set by the setting switch 318 according to the input interval of the zero cross signal. Is determined first.

If the frequencies match, it is determined from the output voltage signal whether or not the peak voltage is substantially equal to the peak value of the voltage set by the setting switch 318. In this way, when the voltage generated between the first output terminal 151 and the second output terminal 152 is compared with the frequency and voltage set by the setting switch 318, and it is determined that they do not match the set values. Outputs an abnormal signal to the display control unit 425 without starting the operation of the PWM signal generation unit 441, and causes the display control unit 425 to output a required display signal to the operation state display unit 427.

When the frequency and voltage match the set values, the PWM signal generator 441 starts operating in accordance with the rise of the zero-cross signal from the rectangular wave forming circuit 317, and the PWM reference table in the PWM reference table is activated. The value is read from the top and output of the first PWM signal and the second PWM signal based on the PWM reference value is started. When the operation of the PWM signal generation section 441 starts, the first PWM signal and the second PWM signal are output based on the modified reference value obtained by modifying the PWM reference value by the modified value by the output voltage waveform monitoring section 433 in the same manner as in the above-described independent operation.
Form a PWM signal.

In this way, the operation of the inverter circuit 130 is started, and a single-phase AC voltage is output between the first output terminal 151 and the second output terminal 152 via the low-pass filter 140. The correct sine-wave single-phase AC voltage is supplied to the engine generator 100 as an AC power supply while making the phase and the voltage of the AC voltage input between the first output terminal 151 and the second output terminal 152 coincide with each other. Output from

After starting the synchronous operation, the synchronous operation control unit 437 sends to the central control unit 310 each time the PWM signal generation unit 441 outputs the first PWM signal based on 0 which is the leading value of the PWM reference value. The input zero-cross signal is determined, and phase adjustment control between the engine generator 100 and another generator is performed. When the first PWM signal based on the PWM reference value is output as shown in (1) of FIG. 5, the single-phase AC voltage which is the output voltage at the time of the synchronous operation becomes the sine of a in FIG. A sine wave having a zero-cross point substantially coincident with 0 of the PWM reference signal shown as a wave is output from the low-pass filter 140. However, when the phase of the voltage output by the engine generator 100 via the low-pass filter 140 and the sine wave voltage output by the other generators are shifted as shown by c in FIG. First
The voltage generated between the output terminal 151 and the second output terminal 152 is a voltage obtained by combining the two voltages as indicated by b in FIG. 5C. That is, the zero-cross point of the reference sine wave shown in (1) of FIG. 5 becomes a sine wave shown in (2) of FIG. 5 and the zero-cross point of the output voltage signal deviates from the zero-cross point of the reference sine wave. become.

Therefore, at the timing when the first PWM signal, which is a control signal based on the PWM reference value 0, is output, if the rectangular wave serving as the zero-cross signal of the output voltage is at the L level, the engine generator 100 outputs a single signal. It is determined that the phase AC voltage is ahead of the voltage output by the other generators operating in parallel, and the first PWM signal and the second PWM
The synchronous operation control unit 437 performs control to extend the period of the reference sine wave shape based on the pulse width of the M signal.

The first PWM based on the PWM reference value 0
If the rectangular wave serving as the zero cross signal of the output voltage is at the H level at the timing when the signal is output, the synchronous operation control unit
437 performs control to shorten the cycle of the reference sine wave. When adjusting the cycle of the reference sine wave formed by the first PWM signal and the second PWM signal, the synchronous operation control unit 437
This is to change the interval of the read clock Kr for reading the PWM reference value from the PWM reference table.

The interval between the read clocks controls a frequency dividing circuit for forming a read clock of the PWM reference value.
Forming several to ten clock signals in which one clock time (a time interval of one step in the PWM modulation cycle) is increased or decreased by several percent to ten percent in one hundred to several hundred clocks forming one cycle. Is what you do.

As described above, the signal is generated between the first output terminal 151 and the second output terminal 152 at the timing of the zero crossing point of the reference sine wave by the first PWM signal and the second PWM signal formed by the PWM signal generator 441. To detect the positive / negative of the voltage, that is, the shift of the zero cross point between the reference sine wave and the output voltage, and adjust the output timing of the reference sine wave, eliminate the influence based on the phase difference between the output voltage and the output current depending on the type of load. The phase difference between the output voltages of the other generators and the engine generator 100 can be accurately corrected.

The output voltage waveform monitor 433 has an output voltage value table as described above, compares the voltage table value read from the output voltage table with the output voltage read by the output voltage signal, and performs PWM. Signal generator 441
A first PWM signal and a second PWM signal based on a PWM reference value.
Even if the pulse width of the pulse signal forming the signal is corrected, if the value of the output voltage detected during the synchronous operation continues to increase with respect to the voltage table value, the coefficient corresponding to the amount of change is used as a PWM reference. By multiplying the first PWM signal and the second PWM signal by a value or a correction reference value, a correction is made to increase the pulse width change of the first PWM signal and the second PWM signal.

In the case of the isolated operation, on the contrary, the correction is performed to reduce the change in the pulse width of the first PWM signal and the second PWM signal so as to reduce the output voltage, and the pulse width of the first PWM signal and the second PWM signal is corrected. According to the adjustment, the voltage table value is also corrected, and the output voltage waveform monitoring unit 433 compares the voltage table value with the output voltage value.

As described above, when the output voltage rises during the synchronous operation, the pulse width change of the pulse signal used as the first PWM signal and the second PWM signal is increased, so that the inverter circuit 130 of the engine generator 100 and the low-pass The value of the single-phase AC voltage output via the filter 140 can be increased to follow a change in the voltage output from another generator operating in parallel.

As described above, in the central control means 310, the output voltage waveform monitoring section 433 and the PWM signal generating section 441 together with the isolated operation control section 435 and the parallel operation control section 437 cause the first output terminal 151 and the second output terminal The first PWM signal and the second PWM signal are output so that the output voltage generated between the first PWM signal and the terminal 152 has a predetermined sinusoidal shape.
Although the PWM signal is formed, the correction of the PWM reference value for forming the first PWM signal and the second PWM signal is performed by adding or multiplying the PWM reference value of the first half cycle of the PWM reference table by PWM. Subtraction or division may be performed on the PWM reference value in the latter half cycle of the reference table.

That is, as described above, the leading value of the PWM reference value stored in the PWM reference table is set to 0, and this PWM
The duty ratio of the pulses in the first PWM signal and the second PWM signal formed corresponding to the reference value of 0 is set to 50%, and the duty ratio based on the value of the PWM reference value is sequentially set to a value exceeding 50% to correspond to the PWM reference value. In the first half period in which the pulse width is changed in a sine wave form, the PWM reference value is set to 0% of the duty ratio in the second half period, and the duty ratio in the second half period is set to a value smaller than 50% based on 50%. When one cycle of the first PWM signal or the second PWM signal is formed by changing the pulse width in a sine wave shape corresponding to each value of the reference value, the PWM reference value is corrected by addition or subtraction throughout one cycle. Things.

Then, the PWM reference value is set to a predetermined positive value other than 0, and the PWM reference value is changed in a sinusoidal manner so as to be larger than the predetermined value and smaller than the predetermined value around the predetermined value. Having a predetermined value stored in the PWM reference table.
The first PWM signal and the second PWM signal whose duty ratio is 50% based on the head of the reference value are PWM
When formed by the M signal generation unit 441, as a correction of the PWM reference value, when performing addition in the first half cycle, subtraction is performed in the second half cycle, and when performing multiplication in the first half cycle, division is performed in the second half cycle. is there.

As described above, by switching between addition and subtraction or multiplication and division in the first half cycle and the second half cycle, as shown in FIG.
As shown in FIG. 7, the first output terminal 151
In a half cycle in which the output voltage V1 is larger than the second output voltage V2, which is the output voltage of the second output terminal 152, an output which becomes a difference voltage between the two terminals by the first output voltage v1 obtained by correcting the first output voltage V1 downward. The voltage V is reduced and the first output voltage V1 is
In the half cycle smaller than the output voltage V2, the first output voltage V1 is corrected to be larger, and the output voltage V can be reduced in the same manner as in the first half cycle.

Further, the central control means 310 controls the DC voltage generation circuit 110 by the circuit protection section 431 and controls the engine speed by the throttle opening degree control section 423. The DC voltage generation circuit 110 by the circuit protection unit 431
Is performed by the stop circuit 360 via the thyristor control circuit 170. As shown in FIG. 3, the stop circuit 360 includes a switching transistor 361 having a base connected to the central control means 310, an emitter of the switching transistor 361 is grounded, and a collector of the switching transistor 361 is connected to the photocoupler 175. It is connected to the cathode of the light emitting diode 177.

When controlling the DC voltage generation circuit 110 by the stop circuit 360, the circuit protection unit 431 is used when the engine is started until the rotation speed signal input from the rotation speed detection circuit 319 is stably maintained. To output a stop control signal to the stop circuit 360 to turn on the light emitting diode 177 and prevent the thyristor control circuit 170 from outputting a conduction signal.

When the rotation speed of the engine is stabilized, the output of the stop control signal is stopped, and the DC voltage detection circuit 32
The voltage of the DC power supply unit 120 becomes 16
After confirming that the voltage reaches a predetermined voltage of 0 to 200 volts, the isolated operation control unit 435 or the synchronous operation control unit 437
, The output of the first PWM signal and the second PWM signal from the PWM signal generation unit 441 is started.

Further, the control of the engine is performed by rotating the pulse motor of the throttle control mechanism 315 forward or reverse by the engine speed detector 421 and the throttle opening controller 423 via the throttle driver 313. When the throttle control mechanism 315 controls the rotation of the throttle valve using a pulse motor, a pulse counter is built in the throttle opening control unit 423, and a rotation control signal output from the throttle opening control unit 423 to the throttle driver 313. The count value is incremented or decremented according to the throttle control mechanism 315.
The throttle opening control unit 423 may store the throttle opening by omitting the opening signal from the controller.

This engine speed control is performed by setting the opening signal input from the throttle control mechanism 315 to a predetermined value in accordance with the output current signal from the output current detection circuit 330, or by controlling the pulse counter of the throttle control mechanism 315. The count value is set to a predetermined value, and a predetermined engine speed is adjusted according to the output. In addition, the ratio of the time during which the conduction signal is output to the DC voltage generation circuit 110 by the cathode potential of the light emitting diode 177 in the photocoupler 175, that is, the throttle opening is modified in accordance with the conduction rate of the thyristor 111, and the high efficiency voltage Conversion is being performed.

Further, in the engine generator 100, when an overcurrent exceeding the rated current flows, the circuit protection section 431 of the central control means 310 performs control to stop the operation of the DC voltage generation circuit 110 and the inverter circuit 130, By stopping the output of the single-phase AC voltage, the power circuit 101 is protected, and the DC voltage generation circuit 110 is
Control to stop the operation of.

Circuit protection section 431 for protecting power circuit 101
When the output current value exceeds 1.2 times the rated voltage, PW is applied after a duration of several seconds to several minutes.
The output of the first PWM signal and the second PWM signal output from the M signal generation unit 441 is stopped, and the stop circuit 36
It is assumed that the output of the stop control signal is started at 0. When the output current value is large according to a value exceeding 1.2 times the rated current, the output of the stop control signal is started in a short time and the first PWM signal and the second PWM signal are transmitted to the PWM signal generation unit 441. Is stopped, and when the value exceeding the rated current is small, the output of the stop control signal is started and the output stop control of the first PWM signal and the second PWM signal is performed for a slightly longer duration, and the output of the single-phase AC voltage is performed. Stop. When the value of the output current reaches more than twice the rated voltage, the output of the first PWM signal and the second PWM signal is immediately stopped, and the output of the stop control signal is started to stop the output of the single-phase AC voltage. .

Further, when the value of the DC voltage detected by the DC voltage detection circuit 320 or the value of the output voltage detected by the output voltage detection circuit 340 becomes abnormally high, the output voltage is the set value. For example, the circuit protection unit 431 sends a stop control signal to the stop circuit 360 when detecting that an abnormal voltage has occurred in the power circuit 101, such as when the voltage drops significantly above 100 volts or when a voltage lower than 100 volts continues. Output, and the PWM signal generation unit 441 stops outputting the first PWM signal and the second PWM signal, so that the first
The output of the single-phase AC voltage from the output terminal 151 and the second output terminal 152 is stopped.

The overcurrent detection circuit 350 provided separately from the central control means 310 outputs an L level stop signal to the photocoupler 175 when the output current value reaches nearly twice the rated voltage. Then, the output of the conduction signal output from the thyristor control circuit 170 to the DC voltage generation circuit 110 is stopped.
For this reason, when the value of the output current reaches nearly twice the rated voltage, each thyristor 111 of the DC voltage generation circuit 110 is turned off, and the power supply from the AC generator 50 to the DC power supply unit 120 is performed. Is stopped. Therefore, the output voltage of DC power supply unit 120 drops.

When the output voltage of the DC power supply unit 120 drops as described above, the output voltage of the DC power supply unit 120 is converted to an AC voltage by PWM control, and the PWM is applied to set a constant duty ratio.
The output voltage, which is the potential difference between the first output terminal 151 and the second output terminal 152 formed based on the first PWM signal and the second PWM signal based on the reference value, is reduced, and the load current is also reduced. The output of the single-phase AC voltage is stopped immediately after the excess, or the output of the single-phase AC voltage is stopped in a very short time when the output current value exceeds 1.2 times the rated current. Can be prevented.

The overcurrent detection circuit 350 is limited to the case where the reference voltage is set so as to output a stop signal when the output current detection circuit 330 detects a current value nearly twice the rated current value. Without, when a current exceeding 1.5 times the rated current value is about to flow, the rectifying operation of the DC voltage generation circuit 110 is stopped, and the power supply from the AC generator 50 to the DC power supply unit 120 is stopped, For example, when reducing the output voltage, the characteristics and durability of the elements forming the power circuit 101,
In addition, according to the safety standard, the central control means 310 is set as an appropriate value together with the output current value when the stop control signal is output.

In the above embodiment, the PWM signal generator
The first PWM signal and the second PWM signal formed in
Although being output to the WM driver 311, the PWM signal generator 441 forms a PWM control signal based on the PWM reference value, as shown in FIG. 10, and a first signal corresponding to the rising edge of the PWM control signal. Dead time signal D
A second dead time signal DT2 corresponding to the fall of T1 or the PWM control signal is formed as a control signal.
The M control signal, the first dead time signal DT1 and the second dead time signal DT2 may be input to the PWM driver 311.

In this case, of the PWM control signal as the control signal output from the PWM signal generator 441 of the central control means 310 and the first dead time signal DT1 and the second dead time signal DT2, the PWM driver 311 performs the PWM control. The control signal and the first dead time signal DT1 are combined to form the first P
A second PWM signal is formed by inverting the PWM control signal, and is combined with the second dead time signal DT2 to form a second PWM signal.
The input from the WM driver 311 to the inverter circuit 130 controls the inverter circuit 130.

[0129]

According to the first aspect of the present invention, there is provided a generator for outputting a DC voltage formed by rectifying an AC voltage generated by an AC generator as an AC voltage having a predetermined frequency from an output terminal by an inverter circuit. The inverter circuit includes a bridge circuit including a switch element, and includes a control unit that outputs a control signal for controlling on / off of the switch element of the bridge circuit. The control signal includes a conduction signal stored in the control unit. An engine generator formed based on time data and dead time data.

Accordingly, the time width of the dead time can be set based on the value of the dead time data, and an arbitrary dead time can be formed, so that the orthogonal transform by the inverter circuit can be performed with high efficiency. . or,
According to a second aspect of the present invention, the control unit has a rewritable storage area, and dead time data for preventing a short circuit of the bridge circuit is input from outside the generator. 1 is an engine generator described in 1;

Therefore, dead time data adapted to the characteristics of the engine generator can be inputted from the outside, and the dead time adapted to the inverter circuit can be set to perform the orthogonal transformation by the inverter circuit with high efficiency. . According to a third aspect of the present invention, there is provided the engine generator according to the first or second aspect, wherein a value of the dead time data is determined by an output voltage of the DC power supply.

Therefore, a dead time can be set according to the voltage applied to the inverter circuit, and efficient orthogonal transformation can be performed in accordance with the operation of the inverter circuit. Further, the present invention described in claim 4 is the engine generator according to claim 1 or 2, wherein the value of the dead time data is determined by the temperature of the generator.

Therefore, the dead time can be changed according to the operation state of the inverter circuit, and the orthogonal transformation by the inverter circuit can always be performed with high efficiency.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an entire engine generator according to the present invention.

FIG. 2 is a circuit block diagram mainly showing a power supply unit of the engine generator according to the present invention.

FIG. 3 is a circuit block diagram mainly showing a detection circuit of the engine generator according to the present invention.

FIG. 4 is a block diagram showing an outline of central control means of the engine generator according to the present invention.

FIG. 5 is a graph showing a voltage output state of the engine generator according to the present invention.

FIG. 6 shows a first PW in the engine generator according to the present invention.
FIG. 4 is a time chart showing an M signal and a second PWM signal.

FIG. 7 is a graph showing a change in the value of dead time data in the engine generator according to the present invention.

FIG. 8 is a block diagram showing another embodiment of the engine generator according to the present invention.

FIG. 9 is a graph showing a correction state of an output voltage.

FIG. 10 shows a PWM in the engine generator according to the present invention.
Control signal, dead time signal, first PWM signal, second signal
FIG. 4 is a time chart showing a PWM signal.

FIG. 11 is a circuit block diagram showing an example of a conventional engine generator.

FIG. 12 is a schematic diagram showing an output voltage.

FIG. 13 is a diagram showing an example of an inverter drive circuit used in a conventional engine generator.

FIG. 14 is a time chart showing a first PWM signal and a second PWM signal having a dead time in a conventional engine generator.

FIG. 15 is a circuit block diagram showing an example of another conventional engine generator.

[Explanation of symbols]

Reference Signs List 50 AC generator 51 Three-phase output winding 55 Single-phase output winding 100 Engine generator 101 Power circuit 110 DC voltage generation circuit 111 Thyristor 115 Rectifier diode 120 DC power supply unit 121 Main smoothing capacitor 130 Inverter circuit 140 Low-pass filter 151 First Output terminal 152 second
Output terminal 160 Gate voltage generation circuit 170 Thyristor control circuit 180 Constant voltage detection circuit 201 Control power supply section 210 Smoothing circuit 221 First constant voltage circuit 225 Second
Constant voltage circuit 230 Regulator 235 Constant voltage circuit 240 Voltage control circuit 250 PWM signal generation circuit 255 Inverter drive circuit 260 Overload detection circuit 265 Operation circuit section 269 Overload detection circuit 270 Sine wave generation circuit 281 Triangular wave generation circuit 285 PWM control signal generation Circuit 291 Square wave generation circuit 293 Start timing circuit 295 Square wave generation circuit 297 Phase comparison circuit 299 Limit value detection circuit 310 Central control means 311 PWM driver 313 Throttle driver 315 Throttle control mechanism 317 Speed detection circuit 319 320 DC voltage detection circuit 330 Output current detection circuit 340 Output voltage detection circuit 350 Overcurrent detection circuit 375 Temperature detection means 380 External memory 432 Throttle opening control unit 431 Circuit protection unit 433 Output power Monitoring unit 435 alone operation control unit 435 synchronous operation control unit 441 PW
M signal generator

Continuing on the front page (72) Inventor: Yasushi Kojima 4-3, Miyatachi, Sakura, Kakuda-shi, Miyagi F-term in Keihin Third Office (Reference) 5H007 CA01 CA03 CB02 CB04 CB12 DA06 DB12 DC02 DC03 DC05 DC08 EA02 EA08 FA03 HA02 5H590 AA02 AB02 AB03 CA07 CA24 CC01 CC18 CC22 CC24 CC34 CD01 CD03 DD64 EA13 EA14 EB02 EB12 EB21 FA01 FB02 FB03 FC12 FC15 FC17 FC21 FC22 FC26 GA02 GA09 GB05 HA02 HA04 HA10 HA18 HA27 HB06 HB14 J02J19B13 J02B

Claims (4)

[Claims] An AC voltage generated by an AC generator driven by an engine is rectified by a DC voltage generating circuit, and the DC voltage is charged to a DC power supply unit. A generator that outputs from an output terminal, wherein the inverter circuit is configured by a bridge circuit including a switch element, and includes a control unit that outputs a control signal for controlling on / off of the switch element of the bridge circuit. An engine generator formed and output based on conduction time data and dead time data stored in a control unit. 2. The engine generator has a rewritable storage area in a control unit, and dead time data for preventing a short circuit of the bridge circuit is input from outside the generator. Item 2. An engine generator according to item 1. 3. The engine generator according to claim 1, wherein a value of the dead time data is determined by an output voltage of a DC power supply unit. 4. The engine generator according to claim 1, wherein a value of the dead time data is determined by a temperature of the generator.