JPS6042325B2 - Turbine generator control method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for controlling a turbine generator,
In particular, the present invention relates to a turbine generator control method and apparatus that are optimal for efficient control at the time of start-up.

In the process of increasing the rotation of the turbine generator to the rated speed, a warm-up operation is performed for a certain period of time at a speed below the normal critical speed when the rotor is started.

It is customary to increase the rotation speed after the vibration has stabilized during this warm-up operation, but the engine passes through many critical speeds before reaching the rated speed. If excessive vibration occurs when passing this critical speed and exceeds the allowable value, the rotor rotational speed is lowered, held constant for a while, and then raised again. This process is repeated, and when the vibration is within the allowable range, the rotation is further increased. On the other hand, if the vibration exceeds a permissible value without being reduced, the conventional method is to temporarily stop the rotor, take countermeasures such as balancing, and then start the rotor again. Conventionally, when the rotor starts up, the rotation increases,
Preparation for determining whether to descend or stop was based on the magnitude of vibrations measured at each rotation speed, so judgments were made after excessive vibrations occurred, which took time and required experience and trial and error. It contained many elements.

As a result, a lot of time is spent on operational control when starting up the rotor. SUMMARY OF THE INVENTION An object of the present invention is to provide a turbine generator control method and apparatus that can efficiently control the operation of the turbine generator at startup.

The present invention calculates the amount of unbalance existing in the rotor from vibrations measured at low speeds before vibrations become excessive, and performs operational control while predicting vibrations at each rotation speed (especially at critical speeds and rated speeds). It is something. FIG. 1 is a block diagram showing an embodiment of the present invention.

The turbine generator consists of turbine rotors 1 and 2 and a generator rotor 3, each of which is connected by a coupling 4 and supported by a bearing 5.

Each of the bearings 5 is provided with a vibration detector 6 that detects vibrations of the journal portion of the bearing 5. These detectors 6
The output signal of the rotary pulse generator 8, which serves as a phase reference signal for discriminating the unbalanced component, is sent to the vibration meter 7, which discriminates the unbalanced component of rotational synchronization. On the other hand, the storage device 9 stores a sensitivity coefficient representing the relationship between weight and vibration every several tens of revolutions, and from this sensitivity coefficient and the unbalanced vibration that is the output signal of the vibration meter 7, it is possible to determine whether the rotor exists in the rotor. The imbalance is estimated by the imbalance calculation device 10 and stored in the storage device 11. Furthermore, the imbalance determiner 12 determines whether or not the estimated imbalance is appropriate. The criteria for determining this unbalance are as shown in Figures 2 and 3. If the vibration is not stable at a certain time and within a certain rotational speed range, the determined unbalance will vary, so the unbalance When the range of change in is within ±ΔW, the unbalance at this time is estimated to be the unbalance remaining in the rotor. This Δw is the storage device 13
be memorized in advance. The vibration calculation device 14 uses the unbalance estimated in this way and the sensitivity coefficient of the storage device 9.
to predict and calculate the vibration at each speed. This predicted vibration value Vp and the vibration characteristic tolerance value Va stored in the storage device 15
are compared by the comparator 16. By this comparator 16, as shown in FIG. 4, when Vp<Va, the rotor rotation is increased as shown in characteristic A, and when Vp)Va, the rotor rotation speed is slightly changed and held there, and then The unbalance is determined and vibration Vp is predicted and calculated. When Vp>Va, the rotor rotational speed is lowered and held as shown in characteristic B shown in Fig. 4 (at this time, the operating conditions may be changed as necessary). ), unbalance estimation and Vp
The above-mentioned comparison is carried out by predicting , and when p<Va, the rotation of the rotor is increased again. However, V
If p<Va and the estimated unbalance is within the range of ±ΔW, the rotor must be stopped and countermeasures such as balancing must be taken. The results of this comparator 16 are sent to a determiner 17, where a change in rotation, a stop, etc. are determined. Furthermore, the output of the determiner 17 is sent to the operation control device 18 to control the turbine generator by sending commands for increasing the rotation, holding, lowering, and stopping the rotation. Here, the principle of calculation performed by the unbalance calculation device 10 and the vibration calculation device 14 will be explained as follows.

The following symbols will be used in the calculation formula below. k: Rotation speed (k=1, 2, K) m: Vibration detection position (m=1, 2, M) n: Unbalance position (n=
1, 2, N) αm<k>n: Sensitivity coefficient at rotational speed k Vm (kゝ: Vibration at rotational speed k Wn(k): Unbalance amount at rotational speed k First, regarding the unbalance calculation device, the following You are asked to do so.

Vibration Vm(k) measured at rotation speed k and storage device 1
From the sensitivity number αm(k)n of 0, if the rotor unbalance is Wn(k>), the following relationship holds: (1) m=
When n, the unbalance amount Wn(k) is I. (11
) When M>N, equation (1) cannot be solved as is.

Therefore, for the unbalance amount Wn(k), vibration Vm(k
) changes by ΔVrTl(k). This relationship is shown by the following equation. At this time, in order to obtain the unbalance Wn(k), the following evaluation function is defined.

The amount of unbalance is obtained under the condition that the evaluation function of equation (4) is minimized.

Here, the subscript T represents transposition.

Further, the vibration calculation device can be calculated as follows.

Unbalance amount Wn obtained by equation (2) or equation (5)
(k), the vibrator measurement value Vm(k)'' at each rotational speed k''(k''=1 to K) is obtained as follows.

By determining the unbalance from vibrations during operation as described above, we can use the fact that the unbalance (residual unbalance) existing in the rotor does not change with rotation to improve the reliability of the generated vibration and improve the reliability of the vibration after the rotation increases. Operation control at the start of rotor operation to predict vibrations, especially at critical speeds and rated speeds, and determine at low speeds whether to increase, hold, lower, or stop the rotor rotation speed. can be done efficiently.

Specifically, various effects can be expected, such as a reduction in the number of control circuits (reduction in start-up time), reduction in start-up and stoppages, ease of automation, and easy labor-saving. As is clear from the above, according to the present invention, the operation of the rotor can be efficiently controlled.

[Brief Description of the Drawings] Fig. 1 is a diagram showing an embodiment of the present invention, Fig. 2 is a diagram of unbalance change with respect to time, Fig. 3 is a diagram of unbalance change with respect to rotation speed, and Fig. 4 is a diagram of unbalance change with respect to rotation speed. There is a characteristic diagram showing the relationship between rotation speed and vibration. 1, 2... Turbine rotor, 3... Generator rotor, 6... Vibration detector, 7...
Vibration meter, 9, 11, 13, 15... Storage device,
10... Unbalance calculation device, 12...
...Unbalance determiner, 14... Vibration calculation device, 16... Comparator, 17... Determiner.

Claims (1)

[Claims] 1. A method for controlling a turbine generator, which detects vibrations of various parts of a turbine generator in which a turbine rotor and a generator rotor are directly connected, and controls the rotational speed of the rotor based on the detected value, The unbalance existing in the rotor is estimated from the set sensitivity coefficient and the above-mentioned vibration detection value, and it is determined whether this value is appropriate or not by comparing it with a pre-set unbalance fluctuation range, and the judgment result is compared with the above-mentioned sensitivity coefficient. A method for controlling a turbine generator, comprising: predicting vibrations up to a rated speed after starting operation based on the predicted value; and controlling the rotational speed of a rotor based on the predicted value. 2. In a turbine generator control device that detects vibrations of various parts of a turbine generator that directly connects a turbine rotor and a generator rotor, and controls the rotation speed of the rotor based on the detected value, detects vibrations of each rotor. a vibration detector,
a rotation signal generator that generates a signal corresponding to the rotation of the rotor shaft; a vibration meter that discriminates a rotation synchronous component from vibration based on each output signal of the rotation signal generator and the vibration detector;
an unbalance calculation device that calculates an unbalance existing in the rotor based on a sensitivity coefficient representing the relationship between the weight and vibration of the rotor and the output of the vibration meter;
an unbalance determiner that determines whether the unbalance value that is the output signal of the unbalance calculation device is appropriate;
a vibration calculation device that calculates predicted vibration based on the output of the imbalance determiner and the sensitivity coefficient; a comparator that compares the output signal of the vibration calculation device with a preset vibration tolerance;
1. A control device for a turbine generator, comprising: a determiner that determines a control style to be performed, such as increasing or decreasing the rotor rotational speed, based on an output signal of the comparator.