JPH01104902A - Electrical speed governor - Google Patents

Abstract

PURPOSE:To execute such control that conforms to a permanent speed variation speedily and accurately by inputting the output of a permanent speed variation operational means into an actuator adjusting means so that it becomes its auxiliary setting via a linear amplifying means. CONSTITUTION:A deviation between the speed desired value of a speed setter 11 and the speed actual value of a speed transmitter 4 is inputted into a speed adjusting circuit 12, while a deviation between the valve opening desired value of this speed adjusting circuit 12 and the valve opening actual value of a differential transformer 18 is inputted into a valve opening adjusting circuit 19, whereby opening of a main steam control valve 5 is adjusted, and thereby the speed of a steam turbine 2 is controlled to its speed desired value. In addition, a deviation between the speed actual value and rated speed of a rated speed setter 13 is inputted into a permanent speed variation arithmetic circuit 14, while the output is inputted in a power adjusting circuit 17. In this case, the output of the permanent speed variation arithmetic circuit 14 is inputted into a permanent speed variation amplification control circuit 20, and simultaneously the output is inputted into the valve opening adjusting circuit 19.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric speed governor for controlling the speed of a prime mover.

[Conventional technology]

FIG. 4 is a block diagram showing a conventional example of an electric speed governor. In FIG. 4, an alternator 3 is connected to a steam turbine 2 as a prime mover, and power from the alternator 3 is supplied to a load (not shown) via a circuit breaker 7. , this steam turbine 2 is controlled as follows.

When the circuit breaker 7 is open, the steam turbine 2 is under no load, and in conjunction with the circuit breaker 7, the contact 7A is open and the contact 7B is closed, so only the speed regulation circuit 12 can operate. . In other words, the speed target value N" from the speed setter 11
Since the deviation from the actual speed value N from the speed transmitter 4 is input to the speed adjustment circuit 12, the speed adjustment circuit 12 sets the valve opening target value to control the input deviation to zero at contact 7B.
Output via . On the other hand, a differential transformer 18 is attached to the electric/hydraulic converter 6, which serves as an actuator that controls the opening degree of the steam control valve 5 that adjusts the amount of steam supplied to the steam turbine 2. The actual value of the valve opening is fed back from the differential transformer 18. Therefore, the valve opening adjustment circuit 19 as actuator adjustment means calculates the deviation between the valve opening target value and the valve opening actual value.
By inputting the signal to the valve opening m node circuit 19, a signal for controlling the input deviation to zero is transmitted to the electric/hydraulic converter 6.
Therefore, the amount of steam is adjusted so that the actual speed value N of the steam turbine 2 matches the desired speed value N''. ゛When the speed of the steam turbine 2 reaches the desired value in this way, Power is supplied to the load by closing the circuit breaker 7 and connecting the AC generators 1 and 3 in parallel to the busbar.At this time, in conjunction with the circuit breaker 7, the contact 7A closes and the contact 7B opens. Therefore, the speed adjustment circuit 12 is disconnected, and the output of the power adjustment circuit 17 is given to the valve opening adjustment circuit 19 as the valve opening target value.In other words, the steam turbine 2 adjusts according to the magnitude of the load. It will be controlled.

A current transformer 8 and an instrument transformer 9 are provided on the output side of the alternating current generator 3, and a power detection circuit 16 detects the actual value P of the power output by the alternating current generator a3.

On the other hand, since the power target value P1 is set by the power setter 15, the power adjustment circuit 17 outputs the valve opening target value that should make the deviation between the power target value P° and the actual power value P zero. That will happen.

Furthermore, a speed adjustment rate calculation circuit 14 is provided, and when the actual speed value N of the steam turbine 2'' deviates from the rated speed N0 of the steam turbine 2 set by the rated speed setting device 13, the deviation is detected. A signal of a predetermined speed regulation rate is inputted from the speed regulation rate calculation circuit 14 to the power adjustment circuit 17 as a supplementary setting signal for the power target value P1, corresponding to the loss and magnitude of the power. This is not only to control the output of the steam turbine 2, but also to correct the deviation when the actual speed value N deviates from the rated speed N.

[Problem that the invention seeks to solve]

By the way, in the above-mentioned conventional method, the speed regulation rate calculation circuit 1
Since the output of 4 is input to the power adjustment circuit 17,
The responsiveness of such speed adjustment rate control largely depends on the output gain of the power Al1 node circuit 17.

In other words, in order to improve the responsiveness of speed adjustment rate control,
If the output gain of the power adjustment circuit 17 is increased, the stability of this control system will deteriorate, and if the output gain of the power adjustment circuit 17 is lowered in order to improve the stability of the control system, then , has the disadvantage that the responsiveness of speed adjustment rate control becomes poor.

In short, this method has a major drawback in that the responsiveness of speed regulation rate control cannot be improved regardless of the stability of the control system.

SUMMARY OF THE INVENTION An object of the present invention is to achieve coordinated speed regulation rate control in an electric speed governor while ensuring the stability of a motor output lJ4-node control system.

[Means for solving problems]

In order to achieve the above object, the electric speed governor of the present invention includes a speed adjusting means for outputting a control signal that matches an actual speed value detected from the prime mover with a target speed value; output adjusting means for outputting a control signal to make the actual output value match the output target value; Speed adjustment rate calculation means inputted to the output adjustment means as an auxiliary setting signal;
Either the speed adjustment means output signal or the output adjustment means output signal is set as a target operation amount value of the actuator for the prime mover, and a deviation between this operation amount target value and an actual operation amount value detected from the actuator is made zero. Actuator 1 that outputs a control signal to this actuator! The electric speed governor comprises a proportional amplification calculation means for inputting the output signal of the speed regulation rate calculation means, and the output signal of the proportional amplification calculation means is applied to the actuator fI adjustment means to operate the hair actuator. It shall be given as a supplementary setting signal for the quantity target value.

[Effect]

In this invention, since the output gain of the output adjustment means cannot be made very high in order to stabilize the control system, it is difficult to adjust the speed by giving the output of the speed adjustment rate calculation means to the output adjustment means. Since it is not possible to improve the responsiveness of constant rate control, the output of the speed adjustment rate calculation means can be actively controlled by manually feeding the output of the speed adjustment rate calculation means to the actuator adjustment means that controls the actuator of the prime mover via the proportional amplification calculation means for the purpose of level matching. The output signal of the speed regulation rate calculation means, which has been conventionally inputted to the output regulation means to perform speed regulation rate control, impairs the stability of the power regulation control system as it obtains the effect of follow-up correction control. This improves the coordination of speed adjustment rate control without causing any problems.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention.

In FIG. 1, a steam turbine 2 as an original FJ+ machine is connected to an alternating current generator 3 and a speed transmitter 4 for detecting the speed of the steam turbine 2, and an electric/hydraulic converter as an actuator. Change the amount of operation of device 6 +
: The opening degree of the steam control valve changes, and therefore the amount of steam flowing into the steam turbine 2 changes, and AC power generation 803
The alternating current output side of is equipped with a transformer 8 for detecting power, an instrument transformer 9, and a power detection circuit 16, and the alternating current generator 3 is connected via a circuit breaker 7 (not shown). The ability to connect to the bus bar and supply power to a load is the same as in the conventional circuit described in FIG. 4. In addition, when the circuit breaker 7 is open, the deviation between the speed target value N" set by the speed setting device 11 and the actual speed value N fed back from the speed transmitter 4 is calculated as the speed 1i1 node circuit 1.
2 and outputted from this speed adjustment circuit 12 via contact 7B, and the valve opening value fed back from the differential transformer 18 that detects the operation amount of the electric/hydraulic converter 6. The speed of the steam turbine 2 is adjusted to the speed target value N'' by inputting the deviation from the actual value to the valve opening adjustment circuit 19, which serves as an actuator adjustment means, and adjusting the opening of the steam control valve 5 using the output of this circuit. matches.

When the speed of the steam turbine 2 reaches a predetermined value, the circuit breaker 7
The AC generator 3 is connected in parallel to the bus bar by closing the circuit, but at this time, the contact 7A is closed and the contact 7B is open.
The steam turbine 2 switches from constant speed control to constant output control. That is, the power target value P1 determined by the power setting device 15
and the actual power value P output by the power detection circuit 16 is input to the power adjustment circuit 178, and the power adjustment circuit 17
The output is given as the valve opening target value to the valve opening adjustment circuit 19 via the contact 7A. At this time, the actual speed value N of the steam turbine 2 and the rated speed N determined by the rated speed setting device 13 are If a deviation occurs between the two, for example N<N, the speed regulation rate calculation circuit 14 operates to increase the electric power according to the amount of deviation, and conversely, if N>No, it decreases the electric output. By operating in this way, drooping characteristics can be obtained. The fact that such a speed adjustment rate calculation circuit output signal is inputted to the power m saving circuit 17 as an auxiliary setting signal is the same as in the case of the conventional circuit described above in FIG.

In the present invention, a regulation rate auxiliary control circuit 20 is installed as a proportional amplification calculation means, and the output of the speed regulation rate calculation circuit 14 is controlled by the regulation rate auxiliary control circuit 20 to a level matching that of the valve opening adjustment circuit 19. Convert it to a signal and use it manually as a supplementary setting signal for the valve opening target value. The output from this regulation rate auxiliary control circuit 20 is such that the steam turbine 2 is at the rated speed N0.
When the valve opening deviates from the target value, the valve opening target value is immediately changed, so in response to this, the valve opening of the steam control valve 5 is changed,
Furthermore, after that, the output of the speed adjustment rate calculation circuit 14 passes through the power adjustment circuit 17 and acts on the valve opening adjustment circuit 19.

FIG. 2 is a circuit diagram showing the inside of the regulation rate auxiliary control circuit 20 in the embodiment circuit shown in FIG. is converted into a signal with a level matching the valve opening adjustment circuit 19.

FIG. 3 is a diagram showing the operation of the embodiment circuit shown in FIG. 1, in which FIG. 3 (a) shows the speed fluctuation of the steam turbine 2, and FIG. 3(c) shows the change in the output of the adjustment rate auxiliary control circuit 20, and FIG. 3(d) shows the change in the composite input to the valve opening adjustment circuit 19.

That is, as shown in FIG. 3, as the speed of the steam turbine 2 changes from its rated value N0, in the case of the conventional circuit, the speed adjustment rate control is performed by the power adjustment circuit 17.
Since this is carried out only through the control, it has the disadvantage of causing a control delay as shown in FIG. 3(b). Note that PNO in FIG. 3 (b) represents the power output when the alternating current generator 3 is at the rated frequency.

By providing the adjustment rate auxiliary control circuit 20 of the present invention,
Since the variation in the rotational speed of the steam turbine 2 is directly applied to the valve opening adjustment circuit 19 (see FIG. 3 (c)), the combined input to the valve opening adjustment circuit 19 is as shown in FIG. (
The result will be as shown in the solid line in (d). The signal indicated by the broken line in FIG. 3(d) is the control signal amount from the speed adjustment rate calculation circuit 14 that is input to the valve opening 311 node circuit 19 via the conventional power adjustment circuit 17. There is.

[Effects of the Invention] According to the present invention, the output signal of the speed adjustment rate calculation means is
By inputting the auxiliary setting to the actuator adjustment means through the proportional amplification calculation means for level matching, the conventional power 1! Since the circuit is configured so that the control by the output signal of the speed adjustment rate calculation means via the adjustment means is follow-up control, even if the prime mover speed fluctuates for some reason, the output of the power adjustment means Regardless of the magnitude of the gain, control according to the predetermined speed adjustment rate is executed quickly and reliably, thereby achieving the effect of achieving speed adjustment rate control with little delay.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a regulation rate auxiliary control circuit 2 in the embodiment circuit shown in FIG.
FIG. 3 is a diagram showing the operation of the embodiment circuit shown in FIG.
The figure is a block diagram showing a conventional example of an electric speed governor. 2... Steam turbine as a prime mover, 3... AC generator, 4... Speed transmitter, 5... Steam control valve, 6...
...Electric/hydraulic converter as actuator, 7...
・A circuit breaker? A, 7B... Contact, 8... Current transformer, 9
...Instrument transformer, 11...Speed setting device, 12...
・Speed adjustment circuit, 13... Rated speed setting device, 14...
・Speed adjustment rate calculation circuit, 15...Power setting device, 16・
...Power detection circuit, 17...Power adjustment circuit, 18...
- Differential transformer, 19...Valve opening adjustment circuit as actuator adjustment means, 2o...Adjustment rate auxiliary control circuit as proportional amplification calculation means. Figure 2

Claims (1)

[Claims] 1) Speed adjustment means that outputs a control signal that makes the actual speed value detected from the prime mover match the speed target value, and output adjustment that outputs a control signal that makes the actual output value detected from the prime mover match the output target value. a speed regulation rate calculation means for inputting a predetermined speed regulation rate signal to the output adjustment means as a supplementary setting signal for the output target value in accordance with the deviation between the rated speed of the prime mover and the actual speed value; means and
Either the speed adjustment means output signal or the output adjustment means output signal is set as a target operation amount value of the actuator for the prime mover, and a deviation between this operation amount target value and an actual operation amount value detected from the actuator is made zero. An electric speed governor comprising an actuator adjusting means for outputting a control signal to the actuator, further comprising a proportional amplification calculating means for inputting the output signal of the speed regulation rate calculating means, the output signal of the proportional amplifying calculating means is applied to the actuator adjustment means as a supplementary setting signal for the actuator operation amount target value.