JP2001359299A - Power generator driven with internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generator driven with an internal combustion engine, which can drive, without problems, a load for soft-start using a self- excitation type field rotary type AC generator as a power generator for driving an internal combustion engine and executing the slow-down control for lowering the number of rotations, under the non-load condition, moreover, without temperature rise in a field coil. SOLUTION: A relay 11, having a contact 11a which holds on state, when a load current does not flow and holds the off state when a load current flows, is provided. A capacitor C2 for increasing magnetization under the slow-down control is connected, in parallel with a capacitor excitation coil Wc of a self- exciting type field rotary AC generator 1 through the contact 11a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine-driven power generator having an internal combustion engine and a self-excited field-rotating AC generator driven by the engine.

[0002]

2. Description of the Related Art In a power generator driven by an internal combustion engine, in order to save fuel of the engine, the amount of fuel supplied to the engine when the load is not driven is reduced to reduce the engine speed. Slowdown control may be performed.

FIG. 2 shows a conventional internal-combustion-engine-driven power generator for performing slow-down control. This power generator includes a self-excited field-rotating AC generator 1 and a control panel 2.
, An internal combustion engine (not shown), a power generating coil 3 for inducing an AC voltage with the rotation of the internal combustion engine, and a solenoid (electromagnet) 4 for adjusting a fuel supply amount to the internal combustion engine.

The self-excited field rotary AC generator 1 includes a stator having a capacitor excitation winding Wc and an output winding WL wound around a stator core (not shown) with a phase difference of 90 °. The rotor comprises a field winding Wf wound around a rotor core and a rectifier Df connected to both ends of the field winding. The rotor is driven by an internal combustion engine.

The control panel 2 is provided with a capacitor C1, a breaker 5, an outlet 6, a current transformer 7, a solenoid excitation control circuit 8, and a rectifier 9. The capacitor C1 is connected to both ends of a capacitor excitation winding Wc. I have.

An AC outlet 6 is connected to both ends of the output winding WL via a breaker 5, and a load (not shown) is connected to the output winding WL via the outlet 6 and the breaker 5.

The generator coil 3 is provided in a magnet generator attached to the internal combustion engine separately from the generator 1, and induces an AC voltage with the rotation of the engine. The AC voltage induced by the power generating coil 3 is converted into a DC voltage by the rectifier 9 and supplied to the power supply terminals 8a and 8b of the solenoid excitation control circuit 8. In this example, the power supply coil 3 and the rectifier 9
Thus, a solenoid driving power supply unit is configured.

[0008] A current transformer 7 constituting a current detector is attached to the wiring connecting the breaker 5 and the outlet 6,
The output of the current transformer 7 is input to detection signal input terminals 8c and 8d of the solenoid excitation control circuit 8.

The solenoid 4 has an excitation coil 4a having one end and the other end connected to a positive output terminal 8e and a negative output terminal 8f of a solenoid excitation control circuit 8, and a displacement when the excitation coil 4a is excited. The resulting movable core 4
b, and a spring (not shown) for returning the movable iron core 4b to the original position. When the exciting coil 4a is deenergized, the movable iron core 4b is held at the original position, and the exciting coil When the magnet 4a is excited, the movable core 4b is displaced to the fuel supply amount limiting position.

The movable iron core 4b of the solenoid is connected to a member for adjusting the fuel supply amount to the internal combustion engine (a fuel supply amount adjusting member such as a throttle lever) through an appropriate connection mechanism. The fuel supply amount adjustment member has a first position at which the fuel supply amount to the engine is set to a first specified amount suitable for a steady operation, and a second specified amount suitable for the fuel supply amount as an amount at a standby operation. The fuel supply amount adjusting member is disposed at the first position when the solenoid 4 is deenergized, so that the fuel supply amount can be changed to the first position. The specified amount is set, and when the solenoid 4 is excited, the fuel supply amount adjusting member is displaced to the second position so that the fuel supply amount is limited to the second specified amount smaller than the first specified amount. Has become.

The internal combustion engine is operated at a rated speed (for example, 3,600 [rpm]) when the solenoid is deenergized (when the fuel supply amount is not limited), and the solenoid is excited to supply fuel. When the amount is limited, the engine is operated at the rotational speed during standby operation (for example, 2,500 [rpm]).

The solenoid excitation control circuit 8 includes a switch circuit for turning on / off a current supplied from the rectifier 9 to the solenoid 4 in accordance with a detection output of the current transformer 7, and the current transformer 7 detects a load current. When no current is present, the switch circuit is turned on, an exciting current flows from the rectifier 9 to the exciting coil 4a of the solenoid 4, and when the current transformer 7 detects a load current, the switch circuit is turned off. The supply of the exciting current to the solenoid 4 is controlled so that the supply of the exciting current to the exciting coil 4a of the solenoid is stopped (the solenoid is demagnetized).

In the example shown in FIG. 2, an output is provided by a solenoid 4, a current transformer 7 as a current detector, a power supply for driving a solenoid comprising a power supply coil 3 and a rectifier 9, and a solenoid excitation control circuit 8. Increases the amount of fuel supplied to the internal combustion engine when the load current is flowing through the windings to increase the engine speed, and decreases the amount of fuel supplied to the internal combustion engine when the load current is not flowing Thus, a slowdown control device is configured to reduce the rotation speed of the internal combustion engine.

In the power generator shown in FIG. 2, when an internal combustion engine (not shown) is started, the rotor of the self-excited field-rotating AC generator 1 rotates, and the residual magnetism of the rotor core excites the capacitor excitation winding. A voltage is induced on the line Wc. As a result, a leading current flows from the capacitor exciting winding Wc through the capacitor C1. The self-excitation phenomenon occurs due to the magnetizing action due to the fast phase current, and at the same time, the field winding Wf passes through the rectifier Df due to the field reverse phase electromotive force generated in the field winding Wf due to the armature reaction of the capacitor exciting winding. Magnetic current flows. The rotor current is excited by this field current, and the voltages of the output winding WL and the capacitor excitation winding Wc are established.

In this generator, the field armature reverse phase electromotive force increases due to the combined armature reaction between the load current flowing through the output winding WL and the leading current Ic, so that the load causes a decrease in the induced voltage of the output winding. It is suppressed, and the voltage fluctuation rate is kept low.

When a load is connected to the output winding WL, the load current is detected by the current transformer 7, so that the solenoid excitation control circuit 8 does not supply an excitation current to the solenoid 4, and the solenoid 8 is deenergized. It is kept in the state. Therefore, when the load is connected, the fuel supply amount adjusting member is held at the first position, and the internal combustion engine is supplied with fuel required during normal operation.

On the other hand, when the load is disconnected from the output winding WL, the load current is not detected by the current transformer 7, and the solenoid excitation control circuit 8 supplies the solenoid 4 with the excitation current. At this time, the solenoid 8 displaces the fuel supply amount adjusting member to the second position on the fuel supply amount reduction side, so that the fuel supply amount to the internal combustion engine is limited, the engine speed is reduced, and the standby operation is performed. State. This prevents wasteful fuel from being supplied to the internal combustion engine when there is no load, thereby saving fuel consumption.

[0018]

As described above, in a self-excited rotating field type AC generator provided with a slowdown device, a load in which a so-called soft start is performed at the time of startup, in which the drive current is gradually increased. (Hereinafter referred to as a soft-start load), the start of the load sometimes failed.

For example, in the case of an electric tool such as an electric drill, which is held by a worker and held by hand, when the electric motor suddenly rotates at the time of starting, a large kickback occurs and the hand may be out of order. After turning on the start switch,
Soft start control is performed in which the drive current is gradually increased by the phase control to gradually increase the rotation speed of the motor toward the rated rotation speed.

In the conventional power generator shown in FIG. 2, the voltage induced in the output winding WL is low when the engine speed is reduced by performing the slowdown control. Is connected to the power generator of FIG. 2, the output winding WL
The load current flowing through the solenoid becomes small, and the solenoid excitation control circuit 8 may not be able to deenergize the solenoid 4, so that the load may fail to start.

In order to prevent such a problem from occurring, the capacitance of the capacitor C1 is increased to increase the exciting ability of the capacitor exciting winding Wc, and a sufficiently high voltage is applied to the output winding WL even during slowdown control. May be induced.

However, when the capacitance of the capacitor C1 is increased so as to increase the induced voltage of the output winding even during the slowdown control, the field electromotive force increases due to the armature reaction during the steady operation, and the field current increases. If increases, thereby increasing the temperature of the field winding Wf, and the field winding may be burned.

An object of the present invention is to provide an internal combustion engine driven power generator for driving a self-excited field rotating AC generator by an internal combustion engine without slowing down the temperature of the field winding when performing slowdown control. Another object of the present invention is to make it possible to drive a load in which a soft start is performed without any problem.

[0024]

According to the present invention, there is provided an internal combustion engine driven power generator comprising: a stator having a capacitor excitation winding to which a capacitor is connected in parallel; an output winding to which a load is connected; and a rotor core. A self-excited field rotary type alternator having a turned field winding and a rotor driven by an internal combustion engine having rectifiers connected to both ends of the field winding; When the load current is flowing through the line, the amount of fuel supplied to the internal combustion engine is increased to increase the rotation speed of the internal combustion engine, and when the load current is not flowing through the output winding, the fuel is supplied to the internal combustion engine. A slowdown control device that reduces the supply amount to reduce the rotation speed of the internal combustion engine; and holds the on state when no load current is flowing through the output winding, and turns the off state when the load current is flowing. Capacitor injection system to hold And use the switch, constituted by providing a connected thrown up during down magnetizing capacitor in parallel with capacitor excitation windings through the capacitor input control switch.

With the above configuration, when no load current is flowing through the output winding WL, the switch for turning on the capacitor is turned on, and the capacitor for slow-down magnetizing is connected in parallel to the capacitor exciting winding. Connecting.
Therefore, the capacitance of the capacitor connected to the capacitor excitation winding increases, and the leading current flowing through the capacitor excitation winding increases, so that the excitation capability increases. Therefore, a high voltage can be induced in the output winding WL even during the slowdown control, and when a soft-start load is connected to the output winding WL, a sufficiently large starting current flows to ensure the start of the load. Can be performed. When the load is started and the load current exceeds the threshold value, the solenoid excitation control circuit 8 deenergizes the solenoid 4, so that the switch for controlling the turning on of the capacitor is turned off, and the capacitor for magnetizing during slowdown is replaced with a capacitor. Disconnect from the excitation winding.
As a result, during steady operation of the generator (when the load is normally driven), the capacitance of the capacitor connected to the capacitor excitation winding decreases, so that the field effect due to the armature reaction during steady operation. An increase in the field current If due to an increase in the electromotive force can be prevented. Therefore, the induced voltage of the output winding at the time of the slowdown control can be sufficiently increased without causing the field winding to be burned out during the steady operation, and the soft-start load can be started without any problem.

With the above configuration, the generator is started up with the load disconnected, so that the generator is started up with the slow down magnetizing capacitor connected to the capacitor excitation winding. Therefore, the voltage of the generator can be quickly established.

The slowdown control device includes, for example, a current detector for detecting a load current flowing through the output winding, a solenoid for driving a fuel supply amount adjusting member for adjusting a fuel supply amount to the internal combustion engine, and a solenoid drive. A solenoid drive power supply that outputs a DC voltage for use, and an exciting current flows from the solenoid drive power supply to the solenoid when the current detector does not detect the load current to excite the solenoid. A solenoid excitation control circuit that deactivates the solenoid when the load current is detected, and displaces the fuel supply amount adjustment member toward the fuel supply amount decreasing side when the solenoid is excited to rotate the internal combustion engine. When the solenoid is de-energized, the fuel supply amount adjusting member is displaced toward the fuel supply amount increasing side to increase the rotation speed of the internal combustion engine. Sea urchin made.

When the slowdown control device is configured as described above, the switch for controlling the supply of the capacitor includes:
A switch is used that maintains the on state when the solenoid is energized and the off state when the solenoid is deenergized.

Such a switch may be constituted by a relay having an exciting coil excited by the voltage between both ends of the solenoid and a normally open contact which closes when the exciting coil is excited. A voltage detection circuit to be detected, and when the voltage detection circuit detects a voltage higher than the threshold value (when the solenoid is energized), the voltage detection circuit is turned on, and the voltage detection circuit detects a voltage higher than the threshold value. And a switch element that is turned off when the is no longer detected (when the solenoid is de-energized).

The switch for controlling the turning on of the capacitor also includes a current detector for detecting an exciting current flowing through the solenoid, and a switch for turning on when the solenoid is energized and the current detector detects a current equal to or larger than a threshold value. And a switch element that is turned off when the current detector stops detecting a current equal to or greater than the threshold value.

The power source for driving the solenoid includes a power generating coil provided in a magnet generator mounted on the internal combustion engine separately from the self-excited field rotating AC generator, and rectifies an AC voltage generated by the power generating coil. Rectifier. Further, the power source for driving the solenoid may be constituted by a battery.

In the above example, the fuel supply amount is adjusted by operating the fuel supply amount adjusting member by the solenoid. However, the supply of fuel to the internal combustion engine is controlled by an injector (electromagnetic fuel injection valve). When using with
By controlling the amount of fuel injected from the injector, the amount of fuel supplied to the internal combustion engine can be adjusted. The amount of fuel injected from the injector can be adjusted by controlling the injection time of the fuel from the injector.

That is, when an injector is used, a current detector for detecting a load current flowing through the output winding and a fuel injection time when the current detector does not detect the load current are set to a value in a normal operation. An injector drive control unit that controls the injector drive current so that the fuel injection time is limited to a time shorter than the injection time and the fuel injection time is returned to the time of the steady operation when the current detector detects the load current. A slowdown control device can be configured.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of the configuration of an internal combustion engine drive generator according to the present invention.
Are denoted by the same reference numerals. In the present invention, in addition to the configuration shown in FIG. 2, the control panel 2 further includes a slow-down magnetizing capacitor C2, and a capacitor input control circuit 10 including a relay 11, a diode D1, and resistors R1 and R2. Is provided. The relay 11 is an exciting coil 4 of the solenoid 4.
a, and a normally open contact 11a that closes when the exciting coil 11y is excited. The slow-down magnetizing capacitor C2 is
It is connected in parallel to both ends of a capacitor C1 through a contact 11a and a resistor R1. Both ends of the capacitor C2 have an anti-R
2 are connected in parallel, and a surge absorbing diode D1 is connected in parallel to both ends of the exciting coil 11y.

The resistor R1 is provided to limit the rush current flowing when the contact 11a is closed, and the resistance value is set to a minimum necessary value to suppress the rush current below an allowable range. Is done. The resistor R2 is connected to the capacitor C
2 is provided to discharge the charge.

The diode D1 is provided to absorb a surge voltage induced in the exciting coil 11y when the solenoid 4 is deenergized and the exciting coil 11y is deenergized. It is provided so as to exhibit a forward direction. That is, the diode D1 is provided with its anode facing the negative output terminal of the solenoid excitation control circuit 8.

In other respects, the construction is the same as that of the conventional power generator shown in FIG. 2. The solenoid 4, a power supply for driving the solenoid comprising the power generation coil 3 and the rectifier 9, and the solenoid excitation control circuit 8 provide A slowdown control device is configured.

The relay 11 keeps the ON state when no load current is flowing through the output winding WL,
A switch for controlling the turning-on of a capacitor, which holds the off state when a load current is flowing, is configured.

In the power generator shown in FIG. 1, when the generator is started with the load disconnected, the relay 11 is energized by the rectified output of the power generation coil 3 immediately after the start and the contact 11a is closed. Are connected in parallel to the capacitor excitation winding Wc. Therefore, the capacitors C1 and C2 are both connected to the capacitor exciting winding Wc, and the leading current flowing through the capacitor exciting winding Wc increases. Therefore, it is possible to enhance the magnetizing effect due to the phase advance current flowing through the capacitor exciting winding Wc, and to quickly establish the voltage of the output winding WL.

When the load is not connected, since the solenoid 4 is excited, the fuel supply amount adjusting member for the internal combustion engine is displaced to the second position on the fuel supply amount reduction side to reduce the fuel supply amount. Limited and slow down control is performed. At the time of the slowdown control, the rotation speed of the engine is reduced. At this time, since the capacitors C1 and C2 are both connected to the capacitor excitation winding and the excitation capability is enhanced, the induction of the output winding WL is induced. The voltage has risen to a value close to the induced voltage during steady operation. In this state, when a soft start load is connected to the output winding WL,
Since a necessary starting current can be passed through the load, soft start of the load can be performed without any trouble. When the load current rises to near the rated value, the solenoid excitation control circuit 8 stops supplying the excitation current to the solenoid 4 and deactivates the solenoid. 1 to increase the fuel supply to the engine. Thereby, the rotation speed of the engine is increased to the rotation speed at the time of steady operation, and the steady operation of the generator 1 is performed. When the generator is in normal operation, the relay 11 is deenergized.
1a is opened to connect the capacitor C2 to the capacitor exciting winding Wc.
Disconnect from Therefore, it is possible to prevent the excitation capability of the capacitor excitation winding from becoming excessive during the normal operation of the generator, and the field current If flowing through the field winding Wf becomes excessive, thereby burning the field winding. Can be prevented.

In the example shown in FIG. 1, the solenoid is excited by using the power generation coil 3 provided in the magnet generator attached to the internal combustion engine as a power source. However, when a battery is provided, The solenoid may be excited by using the battery as a power source.

In the example shown in FIG. 1, the relay 11 is used as a switch for controlling the turning on of the capacitor. This switch keeps the semiconductor switch element and the semiconductor switch on when the solenoid is energized. Alternatively, a switch element control circuit that controls the semiconductor switch to be kept in the off state when the solenoid is deenergized may be used. When the switch for controlling the turning on of the capacitor is configured using a semiconductor switch as described above, the switch may be configured to operate by detecting the excitation voltage supplied to the solenoid 4. May be configured to operate by detecting the exciting current.

In the above description, the solenoid 4 is used as means for adjusting the fuel supply amount of the internal combustion engine, and the solenoid is excited to displace the fuel supply amount adjusting member to the fuel supply amount decreasing side. By deactivating the solenoid, the fuel supply amount adjustment member is displaced toward the fuel supply amount increasing side. However, as described in the section of the means for solving the problem, the supply of fuel to the internal combustion engine is controlled by the injector. In this case, the fuel supply amount to the internal combustion engine can be switched between the supply amount during the steady operation and the supply amount during the standby operation by adjusting the fuel injection amount from the injector. .

[0044]

As described above, according to the present invention, the capacitor input control for maintaining the ON state when no load current is flowing through the output winding and maintaining the OFF state when the load current is flowing. Switch for increasing the capacitance of the capacitor connected to the capacitor excitation winding during the slowdown control because the capacitor for slow down magnetization is connected in parallel with the capacitor excitation winding through the switch. As a result, the exciting ability of the capacitor exciting winding can be increased, and a high voltage can be induced in the output winding. Therefore, when a soft-start load is connected to the output winding, a necessary starting current can be passed to ensure that the soft-start of the load is performed. In addition, since the magnetizing capacitor is separated from the capacitor exciting winding during the slowdown control during the steady operation, it is possible to prevent the field current from being excessively large and burning the field winding during the steady operation. Further, according to the present invention, at the time of starting the generator, the magnetizing capacitor at the time of the slowdown control is caused to function as a starting capacitor, and the exciting ability of the capacitor exciting winding can be increased. Can be quickly established.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration example of an internal combustion engine drive power generation device according to the present invention.

FIG. 2 is a circuit diagram showing a configuration of a conventional internal combustion engine driven power generation device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Self-excited field rotation type AC generator, 2 ... Control panel, 3 ... Generating coil, 4 ... Solenoid, 6 ... AC outlet, 7 ...
Current transformer (current detector), C1 ... capacitor, C2 ... capacitor for slow-down control magnetizing, 11 ... relay.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3G093 AA16 BA02 BA08 CB04 DB20 EA05 EB09 FB01 FB02 5H590 AA28 AB07 CA23 CC19 DD42 EA01 FA01 FA05 FC22 FC23 FC25 FC26 FC28 GA09 GA10 HA04 JB10 5H607 BB02 CC05 DD03 5DD02FF02 PP02 PP12 PP14 PP32

Claims (2)

[Claims] 1. A stator having a capacitor excitation winding to which a capacitor is connected in parallel and an output winding to which a load is connected, a field winding wound around a rotor core, and both ends of the field winding. A self-excited field rotating AC generator having a rectifier connected to the internal combustion engine and having a rotor driven by the internal combustion engine; anda load current flowing through the output winding to the internal combustion engine. To increase the engine speed by increasing the amount of fuel supplied to the engine, and reduce the amount of fuel supplied to the internal combustion engine when no load current is flowing through the output winding, thereby increasing the engine speed. A slow-down control device for reducing the load, a capacitor-on control switch for holding an on-state when no load current is flowing through the output winding, and holding an off-state when the load current is flowing, Capacitor throw A slow-down magnetizing capacitor connected in parallel to the capacitor exciting winding through an on-control switch. 2. A stator having a capacitor excitation winding to which a capacitor is connected in parallel and an output winding to which a load is connected, a field winding wound around a rotor core, and both ends of the field winding. A rectifier connected to a self-excited field rotating AC generator having a rotor driven by an internal combustion engine, and a current detector for detecting a load current flowing through the output winding; A solenoid that drives a fuel supply amount adjustment member that adjusts a fuel supply amount to the internal combustion engine, a solenoid drive power supply that outputs a DC voltage for solenoid drive, and when the current detector does not detect a load current. An exciting current is supplied to the solenoid from the power source for driving the solenoid to excite the solenoid, and when the current detector detects a load current, solenoid excitation control is performed to deactivate the solenoid. When the solenoid is energized, the fuel supply amount adjusting member is displaced toward the fuel supply amount decreasing side when the solenoid is excited to reduce the rotational speed of the internal combustion engine, and when the solenoid is deenergized, the fuel supply amount is adjusted. A slowdown control device that displaces a supply amount adjusting member toward a fuel supply amount increasing side to increase the rotation speed of the internal combustion engine; and holds the on state when the solenoid is energized, and deactivates the solenoid. An internal combustion engine, comprising: a capacitor turning-on control switch that maintains an off state when the switch is turned on; and a slow-down magnetizing capacitor connected in parallel to the capacitor excitation winding through the capacitor turning-on control switch. Drive generator.