JPS61109498A - Controller of engine-driven generator - Google Patents

Abstract

PURPOSE:To switch use and nonuse of automatic idling function by connecting a quasi-load circuit for adding a quasi-current to a load current detector in an interruption enabling manner. CONSTITUTION:The rotating speed of a generator 2 is detected by a rotating speed detector 6, the load current of the generator is detected by a load current detector 7, and the detection signals are respectively input to a controller 4. The controller 4 outputs a control signal to a drive circuit 8 on the basis of the input signals and the contained program, and controls the opening of a throttle valve 5. When a quasi-load circuit 10 is connected with the detector 7, the quasi-current of the prescribed amplitude is applied to the detector 7 to set the automatic idling function to unused state.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is directed to the control of an engine-driven generator that directly connects an E7 engine to a generator and obtains a voltage output at a predetermined frequency by controlling the engine speed. Regarding equipment.

[Prior art]

Engine-driven generators are generally constructed by directly connecting an alternating current generator to a generator/engine, and are widely used as a power source for various work equipment or electrical equipment in places where an appropriate power source is not available.

The frequency of AC power supply is generally 50 H2 or 60 H2
In some cases, a rated frequency specific to the equipment (load) may be adopted. Therefore, in an engine-driven generator, it is necessary to control the engine speed to a constant rated speed even in response to fluctuations in load current.

The rotational speed control described above can be performed by a mechanical coupler, but recently electronic control using a microcomputer has come into practical use.

This microcomputer-based control device is configured to control the throttle according to the load and maintain a constant rotation speed.
Some models have an auto-idle function that switches to idle link when the load is very light. In addition, in the case of a control device with an auto-idling function, in consideration of the fact that the load may be constantly turned 0N-OFF, such as in an electric welding machine, it may take time for the load current to rise, reducing work efficiency. A system has been proposed that can switch to a state in which the auto-idle function is not used in such cases.

However, in this type of conventional engine-driven generator control device, the load current detection circuit and auto-idle switching circuit were each connected to a microcomputer (control circuit), so the control circuit using the microcomputer was independent. However, this method requires two input ports, making the control circuit complicated and expensive.

Furthermore, the microcontroller program has to be created for both load current detection and auto-idle function, which makes it complicated.In addition, cheap microcontrollers with limited glodulum capacity have other problems due to the increase in glodulum capacity. There was also the problem that functions (for example, display functions) could not be realized.

〔the purpose〕

The purpose of the present invention is to solve the problems of the prior art,
An object of the present invention is to simplify the software and hardware of a control device for an engine-driven generator that can implement an auto-idling function under microcomputer control and switch between use and non-use of the auto-idle function, thereby reducing costs.

〔composition〕

The present invention detects the load current of a generator, closes the engine throttle to idle when the load current is below a predetermined value, and controls the engine throttle when the load current is above a predetermined value to maintain the engine at the rated rotation speed. In a control device for a drive generator, a pseudo load circuit that adds a pseudo current is connected in an intermittent manner to a load current detection circuit, and the rotation speed is always maintained at the rated rotation speed regardless of the load current by adding the pseudo current. By doing so, the above purpose is achieved.

〔Example〕

The present invention will be specifically described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall structure of a control device for an engine-driven generator according to the present invention.

In FIG. 1, a generator (alternating current generator) 2 is coupled (generally directly connected) to the output shaft of an engine 1, and the alternating current output of the generator 2 drives a load 3 such as a working machine or electrical equipment. If the rated frequency of load 3 is 50H2, the corresponding 30θOrpm, and if it is 60Hz, a
soorpm, the control circuit (microcomputer) 4 is configured to control opening and closing of the throttle valve 5 of the engine 1 so that the engine operates at a rated rotational speed corresponding to the rated frequency of the load.

The rotation speed of the generator 2 is detected by a rotation speed detection circuit 6, the load current of the generator is detected by a load current detection circuit 7,
Each detection signal is input to a control circuit (microcomputer) 4. The control circuit 4 executes predetermined arithmetic processing based on these input signals and the built-in program, and the resulting output (control signal) is input to the drive circuit (driver) 8.

The drive circuit 8 operates in response to a control signal, supplies a drive current according to the control signal to a drive device 9 (for example, a rotary actuator, etc.) for driving a throttle valve, and operates the drive device by a predetermined amount. In this way, throttle pal f5
The opening force is controlled and the engine 1 is operated at a set rotation speed (rated rotation speed).

In this case, the load current of the electrical machine 2 is detected by the load current detection circuit 7.
When the load is small and the load current is below a predetermined value, the throttle valve 5 is closed and the engine is idled (for example, at t
oooorpm), and at other times, the opening degree of the throttle valve 5 is controlled according to the magnitude of the load to maintain the generator 2 at the rated rotation speed. That is,
It has an auto idle function.

However, in the control device of the present invention, as shown in FIG. The auto-idle function is configured to be disabled depending on the vehicle.

That is, in the control device of the present invention, as shown in FIG. 2 or FIG. It is constructed so that the rated rotation speed can be maintained at all times regardless of the load current.

FIG. 2 shows a case where the load current detection circuit 7 with a pseudo load circuit is configured in an analog type.

In FIG. 2, a load current AC of an alternating current generator is taken out by a current transformer 11, half-wave rectified by a rectifier 12, and then smoothed by a cypress circuit 13 to obtain a load current detection signal V. This detection signal V is input to a child terminal of the comparator 14.

On the other hand, one terminal of the comparator 14 receives a setting signal V adjusted by dividing the DC power supply Vcc. is input.

The comparator 14 compares and calculates both signals V#V□, and V
. If it is larger, the output of the comparator 14 is turned ON, and an ON signal is manually inputted to the control circuit (microcomputer) 4.

In this case, the control circuit 4 operates to control the throttle valve opening and drive the engine 1 and the generator 2 at a constant rated rotation speed. On the other hand, the detection signal V is the setting signal V(
), that is, when the load current is less than a predetermined value, the output of the comparator 14 is turned off, and the control circuit 4 operates to close the throttle valve 5 and perform idle link operation.

However, a pseudo load circuit 10 is connected to the child terminal of the comparator 14.
is connected, and by closing the switch 15, the setting signal V. It is configured to add a larger pseudo current 7. Therefore, by closing the switch 15, the output of the comparator 14 is always turned on, the auto-idle function is put out of use, and the rotation speed can be maintained at the rated speed regardless of the load current.

FIG. 3 shows a case where the load current detection circuit 7 with a pseudo load circuit is configured in a digital manner.

The circuit in Figure 3 is the load current detection circuit in Figure 2.27
It is connected to the control circuit (iiko/) 4 through a circuit 16 similar to the above, and a pseudo load circuit 10 is connected to the other input terminal of the OR circuit 16. The pseudo load circuit 10 in this case is configured to input the pseudo current V from the DC power supply Vcc to the OR circuit 16 through the buffer 18 when the switch 17 is opened, and to turn off the pseudo current ■ when the switch 17 is closed. There is.

Therefore, when the switch 17 is closed, the auto idle function is activated and the load current detection signal V becomes the setting signal V. When the value is greater than 1, the 111 signal is input to the control circuit, and the control circuit 4 operates to control the throttle valve 5 to drive it at a constant rated rotation speed, while the detection signal V is the setting signal V.

When it is smaller, both of the two inputs of the OR@ path 16 become O, and the control circuit 4 operates to close the throttle group 5 and perform idle link operation.

On the other hand, when the switch 17 is opened, the output of the OR circuit 16 is always 111 and the auto-idle function is not used, and the control circuit 4 always controls the throttle valve adjustment and always operates at the set rated speed even when the load current is small. It operates to be driven by numbers.

According to the control device for the engine-driven generator illustrated and explained above, the pseudo load circuit 10 for adding a pseudo current is connected to the load current detection circuit 7, and the switch 15.17 is configured to intermittent the pseudo current. , control circuit 4 for switching between use and non-use of the auto idle function
The number of input ports can be reduced to one, the control circuit 4 can be made smaller and simpler than the conventional structure, and manufacturing costs can be reduced.

Furthermore, a single microcontroller GLODARAM is required for the load current detection and auto-idle functions, making it possible to simplify the software and increase the program capacity at the same time.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the hardware and software of a control device for an engine-driven generator with an auto-idling function that can switch between using and not using the auto-idling function can be simplified and the cost can be reduced. can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the overall configuration of a control device for an engine-driven generator according to the present invention, and FIGS.
FIG. 3 is a circuit diagram illustrating a case where the load current detection circuit and the pseudo load circuit shown in the figure are configured in an analog type and a case in which they are configured in a digital type. 1...engine, 2...generator. 3...Load, 4...Control circuit. 5... Throttle valve. 7...Load current detection circuit. 10...Pseudo load circuit. V: load current detection signal, vo: setting signal. ...Pseudo load signal (pseudo current).

Claims (1)

[Claims] (1) Engine drive that detects the load current of the generator, closes the engine throttle to idle when the load current is below a predetermined value, and controls the engine throttle to maintain the rated rotation speed when the load current is above a predetermined value. In a generator control device, a pseudo load circuit that adds a pseudo current is connected in an intermittent manner to a load current detection circuit, and the rotation speed is always maintained at the rated speed regardless of the load current by adding the pseudo current. Control device for engine-driven generator.