JPS5812598A - Operating method for diesel generator with supercharger - Google Patents

Abstract

PURPOSE:To improve the characteristic of a Diesel generator at the time of applying a load to the generator by gradually increasing the output voltage of the generator from the initial value lower than the rated value to the rated value in response to the magnitude of the applied load power. CONSTITUTION:A load current detector 15 detects the application of a load 13 by the output signal of a current transformer 14. A wattmeter 16 detects the applied load power, sets the initial voltage lower than the rated value to an initial voltage setter 17 when the applied load power is so large as to abruptly decrease the rotating speed of an engine, and sets the rising time from the initial voltage to the rated voltage to a rising time setter 1. A function generator 19 receives a signal from a load current detector 15 and generates a function signal gradually increasing from the initial voltage to the rated voltage. An automatic voltage setter 7' receives the function signal and is automatically set, thereby controlling the excitation with a thyristor 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of operating a highly supercharged diesel generator, and more specifically, to a method of operating a highly supercharged diesel generator, and more specifically, a method for preventing a sudden drop in engine speed when a load is applied and shortening the time required for recovery. It's about how you can do it.

As is well known, when the degree of supercharging of a diesel engine increases, the trap supercharger becomes unable to follow the load, and transient incomplete combustion occurs due to lack of air, resulting in a rapid increase in rotation speed. In severe cases, the engine may stall.

As a countermeasure against this problem, there is a known technique (for example, Japanese Utility Model Publication No. 44-2241) in which an air tank is prepared in advance and air is separately supplied from the air tank at the same time as the load is applied.

However, such measures were not practical due to their high equipment costs and little effectiveness. On the other hand, as an electrical means, a thyristor excitation control system is known, but its effectiveness is not sufficient.

The purpose of the present invention is to overcome these drawbacks of the prior art and
The object of the present invention is to provide a new method that can improve the characteristics when a load is applied by improving the conventional excitation control method without separately providing extra equipment such as an air tank.

The applicant has already filed an application regarding the method of operation when applying a load during no-load conditions (Japanese Patent Application No. 56-254).
No. 07), the present invention particularly relates to an operating method when applying a load during partial load.

That is, in the present invention, when a load is applied to a highly supercharged diesel generator at partial load, the applied load power is detected by the load power detection means, and 1. The initial generator voltage is set according to the magnitude of the input load power, and the generator voltage is gradually increased to the rated value using a famous dynamic voltage adjustment means having a function generator. It is something to do.

Hereinafter, the present invention will be specifically explained with reference to the drawings.

Figure 1 is a schematic diagram of a conventional highly supercharged diesel generator.
FIG. 2 is a schematic configuration diagram of a highly supercharged diesel generator according to an embodiment of the present invention, and FIGS. 3(A) to 3C) are graphs for explaining the present invention in detail.

In FIG. 1, a diesel generator is constituted by a highly supercharged diesel engine 1 and a generator 2, and an excitation circuit 6 and an automatic voltage regulator 4 are connected to excite and control the diesel generator. In addition, the load 16 is connected via the circuit breaker 12.
is connected.

Assuming that the generator is currently in operation, the output voltage of the generator 2 is detected by the voltage detector 6 via the transformer 5, and the detected voltage V and the preset setting are adjusted by the voltage setting device 7. An amplifier 8 amplifies the deviation signal (Vo-V) from the voltage vo. The amplified signal is passed through the phase controller 9 and the gate pulse generator 10 to generate a gate pulse synchronized with the terminal voltage of the generator 2.
It is used as an ignition signal.

That is, negative feedback is performed so that the output voltage (2) of the generator 2 detected by the voltage detector 6 and the voltage V set by the voltage setting device 7 are equalized, thereby performing cyrisk excitation control.

However, in such a conventional method, it is necessary to manually determine the value of the set voltage Vo by operating the voltage setting device 7 each time. Therefore, the control accuracy was poor and it was not possible to follow sudden changes when the load was applied.

The present invention is an improvement on that method, and FIG. 2 shows a schematic configuration of an example of a device for implementing the method.

That is, a current transformer 14 is installed between the generator 2 and the breaker 12.
is provided, and by sending the signal to the load current detector 15, the application of the load 13 is detected.

On the other hand, the output voltage of the generator 2 is detected via the transformer 5,
A wattmeter 16 connected to these current transformers 14 and transformer 5
The applied load power is detected by

(a) If the input load power is large enough to cause a sudden drop in engine speed, the output of the initial voltage setter 17 connected to the output side of the wattmeter 16 is set to the rated voltage of the generator 2
The initial voltage Vi is automatically set to a value that is lower than n but does not affect the partial load that has already been applied. Further, a rise time ti from the initial voltage Vi to the rated voltage vn is automatically set by a rise time setter 18 connected to the output side of the initial voltage setter 17. Note that the wattmeter 16° initial voltage setter 17 and rise time setter 18 can be installed together by the microcomputer 20.

A function generator 19 connected to the output sides of the initial voltage setter 17 and the rise time setter 18 receives the signal from the load current detector 15, and from the time the load is turned on, the voltage is set from the initial voltage Vi to the rated voltage vn with a rise time J. Generates a function signal that gradually increases.

In response to the function signal, the automatic voltage setting device 7' outputs o
is automatically set. Thereafter, excitation control by the thyristor 11 is performed by the same mechanism as described above.

(b) Alternatively, if the input load power is not so large as to cause a sudden drop in engine speed, the initial voltage Vi is set to the rated voltage ■. In some cases, it may not be necessary to lower the value. In other words, when the input load power is small, the initial voltage V
B = rated voltage vn, and rise time ff1i = o
And it is sufficient.

In this way, the output voltage of one generator is gradually increased from an initial value lower than the rated value to the rated value depending on the magnitude of the input load power (a), or in special cases, the initial value is increased to the rated value. By setting (b), regardless of the magnitude of the input load power, the engine speed, which conventionally drops suddenly after load application, can be suppressed to a slight drop, and the time required for recovery is shortened. Highly supercharged diesel generators can be operated stably without affecting the current load.

The situation is shown in FIGS. 3(A) to (C'l).

In (A), the solid line is when the input load power is large (a
), the broken line shows the case (b) when the input load power is small. In (B) and (C), the solid line shows the case when the operating method of the present invention is used, and the dashed-dotted line shows the case when the conventional operating method is used.

As shown in (B), in the conventional case, the load current suddenly changed in IK at the same time as the load was applied, but according to the present invention, it changes gradually.

(As shown in Q, conventionally the engine speed suddenly decreased at the same time as the load was applied, but according to the present invention, the speed decrease is △n
o is small (Δno <Δn), and the time t6 required for recovery is also short (to<t').

As described above, according to the present invention, it is possible to suppress the engine rotational speed, which has conventionally dropped sharply after load application, to a slight decrease, and also to shorten the time required for recovery. Therefore, the highly supercharged diesel generator can be stably operated without any trouble even after the load is applied.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a conventional highly supercharged diesel generator.
FIG. 2 is a schematic configuration diagram of a highly supercharged diesel generator according to an embodiment of the present invention, and FIGS. 3(A) to 3(C) are diagrams for explaining the present invention in detail. 1... Highly supercharged diesel engine, 2... Generator, 3...
... Excitation circuit, 4'... Automatic voltage regulator, 6... Voltage detector, 7'... Automatic voltage setter, 8... Amplifier, 9... Phase controller, 10...・Gate pulse generator, 11... Thyristor, 13... Load, 15...
Load current detector, 16... Wattmeter, 17... Initial voltage setting device, 18... Rising time setting device, 19... Function generator.

Claims (1)

[Claims] When applying a load during partial load of a highly supercharged diesel generator, the applied load power is detected by a load power detection means,
The initial generator voltage is set according to the magnitude of the input load power, and using an automatic voltage adjustment means having a function generator,
A method of operating a highly supercharged diesel generator, characterized in that the generator voltage is gradually increased to a rated value.