JP3468921B2 - Turbine generator frequency control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency control device for each turbine generator in a power plant in which a plurality of turbine generators are connected in parallel to the same power load. More particularly, the present invention relates to a frequency control device for a turbine generator in which the rotation speed of each turbine (steam turbine, gas turbine) as a prime mover of each turbine generator is individually controlled to control the frequency of generated power. 2. Description of the Related Art A conventional technique will be described with reference to FIGS.
Conventionally, as shown in FIG. 3, the same power system (power load)
When two first and second turbine generators 01 and 02 are connected in parallel to each other and their power loads are separated from the commercial power system, each of the turbine generators is controlled by the following frequency control device. Control (rotation speed control) is performed. That is, steam or fuel is supplied to a turbine (steam turbine or gas turbine) of a first turbine generator 01 via a steam or fuel control valve (turbine control valve) 13, and the frequency of the turbine generator 01 is controlled. The output of the detector 11 is sent to a P-type or PID-type frequency controller 1a. The frequency setpoint signal f ₀ is sent to the frequency setter 2a, the output of the frequency setting device 2a is sent to the frequency controller 1a, the correction control signal 1A outputted from the frequency controller 1a of the turbine control valve 13 Opening / closing control is performed, and rotation speed control of the first turbine generator 01, that is, frequency control is performed. Reference numeral 3 indicates a frequency target value setting device. A similar frequency control device is provided for controlling the turbine control valve 13 of the second turbine generator 02. Then, P or PID calculation is performed by each frequency controller 1a according to the input deviation, and the correction control signal 1A
Is sent to each turbine control valve 13, and each turbine control valve 13 is controlled. When the turbine generators 01 and 02 are operated in parallel, a PID controller (proportional + integral + differential control) cannot be used for a plurality of frequency controllers. A control system that employs a P controller (proportional control) for the frequency controllers of all the turbine generators can be considered. In this case, although the load (power generation output) of each turbine generator can be made substantially equal, the frequency setting value (turbine rotation speed setting value, output signal of the frequency setting device 2a) and the measurement frequency (frequency) Output signal of detector 11)
, A deviation proportional to the load of the turbine generator remains, and the deviation increases as the load increases (see FIG. 4). Therefore, in the case of this control method, there is a problem that the frequency cannot be kept constant regardless of the load. On the other hand, one (for example, the first turbine generator 0)
A control method in which the PID control method is used only for the frequency controller 1) and the P control method is used for all other frequency controllers (for example, the second turbine generator 02) is also conceivable. In this case, in the turbine generator adopting the PID control method, the load is adjusted so that the deviation between the set frequency and the measured frequency is made zero, so that the frequency can be kept constant (see FIG. 5). ). But PID
Only the first turbine generator provided with the frequency controller of the control system is load-controlled, and the load becomes constant in the second turbine generator provided with the frequency controller of the P control system. There is a problem that they are not equal. That is, the above-mentioned conventional frequency control device has the following problems. (a) If the P control method is adopted for each turbine generator so that the load of each turbine generator becomes equal, the frequency changes according to the load. (b) If only the control of one turbine generator is set to the PID control system and the control of the other turbine generators is set to the P control system so that the frequency is kept constant even if the load changes, Loads are not equal. The present invention seeks to solve such a problem. [0009] Therefore, a frequency control apparatus for a turbine generator according to the present invention is provided in a power plant in which a plurality of turbine generators are connected in parallel. A valve, a frequency setting device, a frequency detector, a frequency control device of a P control type for receiving a respective output of the frequency setting device and the frequency detector and outputting a correction control signal to the turbine control valve. Each machine is equipped with a load detector,
An average load calculator for calculating an average load from the output of each load detector and the number of the turbine generators is provided, and the average load calculator and the turbine generator are provided for each of the turbine generators. A load corrector that receives the output of the load detector and sends a load correction signal to the frequency setting device of the turbine generator; and a frequency correction device that receives the frequency target value signal of the turbine generator and the output of the frequency detector. A frequency corrector for transmitting a signal to the frequency setting device of the turbine generator, wherein the frequency setting device corrects a correction frequency setting value signal corresponding to the load correction signal and the frequency correction signal of the turbine generator. Is output. In the above-described frequency control apparatus for a turbine generator according to the present invention, one average load calculator calculates the output signal of each load detector of all the turbine generators operating in parallel and generating power. receiving a number of operating signal, and outputs the average load L _m of the turbine generator per one. The load compensator receives the load L ₁ and the average load L _m of its own turbine generator and receives L ₁ <L _m
If outputs a load compensation signal of "+" and L _1> if L _m - outputs a load compensation signal for "". That L ₁ outputs an L _m and comprising (a L ₁ closer to L _m) as a load correction signal. The frequency corrector receives the frequency target value f ₀ and the output (detection frequency) f ₁ of the frequency detector of its own turbine generator, and outputs a frequency correction signal of “+” if f ₁ <f _0. If f ₁ > f ₀ , a frequency correction signal of “−” is output. That is, a frequency correction signal is output such that f ₁ becomes f _O (f ₁ approaches f ₀ ). The frequency setter receives the above correction signals of the load corrector and the frequency corrector, and increases when each of the correction signals is a “+” input,
When the input is "-", the correction frequency set value that decreases is output. The P-control frequency controller receives the output f ₁ of its own frequency detector and the correction frequency set value, and sends a correction control signal to its turbine control valve by P-calculation of the deviation. The opening / closing degree of the turbine control valve is adjusted by the correction control signal such that the load of the turbine generator approaches the average value and the frequency approaches the target value. Therefore, the loads of the respective turbine generators operating in parallel increase and decrease equally, and the frequency is maintained at the frequency target value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a frequency control device for a turbine generator according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a system diagram, and FIG. Note that the same reference numerals in FIG. 1 as those in FIG. 3 indicate substantially the same members.
Also in this embodiment, the first turbine generator 01 and the second turbine generator 02 are connected in parallel to the same power load to generate power. First and second turbine generators 01 and 02
Are provided with load detectors 12, respectively. Outputs of the respective load detectors 12 of the turbine generators 01 and 02 are sent to a divider 8 via an adder 7, and an average load of each turbine generator is calculated. Is done. The divisor N of the divider 8 is the number of all turbine generators that are generating power by operating in parallel, and the output of the divider 8 is sent to the frequency setting device 2 via the load compensator 5. Reference numeral 6 denotes an average load calculator, and an adder 7 and a divider 8
The average load calculator 6 is one irrespective of the number of turbine generators operated in parallel. The load compensation device 5 includes a load comparator 5a for comparing the detected load detector 12 of the first turbine generator 01 load L ₁ and the average load L _m, L the load comparator 5a "-" when the _1> L _m load compensation signal is also at the time of L ₁ <L _m is output load compensation signal of "+". Reference numeral 4 denotes a frequency compensator. The frequency compensator 4 detects the frequency target value f ₀ set by the frequency target value setter 3 and the frequency detector 11 of the first turbine generator 01. Frequency comparator 4 for comparing the calculated frequency f ₁ (the frequency of the power generated by the first turbine generator 01)
equipped with a, when the frequency comparator 4a of f _1> f ₀ is "-" is the frequency correction signal, also a frequency correction signal "+" is output when the f ₁ <f _0. Then, the "-" or "+" frequency correction signal of the load compensator 5 and the "-"
Alternatively, the frequency correction signal of “+” is input to the frequency setting device 2. The frequency controller 1 is P
The frequency controller 1 of the P control system is provided with a correction frequency set value signal 2
A and the frequency signal from the frequency detector 11 of the first turbine generator 01 are input, respectively, and the two signals are compared. On the other hand, the control system of the turbine control valve 13 of the second turbine generator 02 also includes the frequency corrector 4, the frequency setter 2 and the frequency controller 1 in the control system of the first turbine generator 01 described above. A frequency compensator, a frequency setting device, and a frequency controller (of the P control system) (all not shown) having the same configuration are provided. In the above configuration, one average load calculator 6 is provided for all the turbine generators.
Receives the output of each load detectors 12 of all the turbine generator is performing power generation by parallel operation, and outputs the average load L _m per one respective turbine generators. The load compensation unit 5 is provided to each turbine generator 01, 02, the load L ₁ and the average load L _m of each turbine generator itself are input, L ₁ <L _m
Then, a load correction signal of "+" is output. Also, L ₁ > L _m
Then, a load correction signal of "-" is output. That each load corrector 5, each L ₁ outputs a load compensation signal such that the L _m. The frequency compensator 4 is also used for each of the turbine generators 01 and 02.
To be provided respectively, the frequency corrector 4 receives the output f ₁ output f ₀ and its respective frequency detector 11 of the turbine generator of the frequency desired value setter 3, respectively, f ₁
If <f ₀ , a frequency correction signal of “+” is output, and f ₁
If> f ₀ , a “−” frequency correction signal is output to each frequency setting device 2. That is, each frequency corrector 4 outputs a frequency correction signal such that f ₁ becomes f ₀ to each frequency setter 2. The frequency setter 2 is also used for each of the turbine generators 01 and 02.
, And receives the output from each of the load compensator 5 and the frequency compensator 4, and increases when the input is “+” and decreases when the input is “−”. 2A is output. The frequency controller 1 of the P control system is also provided in each of the turbine generators 01 and 02, and the output f of the frequency detector 11 of the own turbine generator is provided.
₁ and the signal of the correction frequency set value 2 are received, and the frequency correction control signal 1A is sent to the turbine control valve 13 of the own turbine generator by P calculation of the deviation. Each of the turbine control valves 13 has a corresponding correction control signal 1A.
To adjust the amount of steam or fuel supplied to its own turbine, to adjust the load of its own turbine generator to an average value, and to adjust the rotation speed of the turbine so that the frequency approaches a target value (FIG. 2). reference). In this way, the turbine generator frequency control device of this embodiment can control the two turbine generators 01 and 02 that are operated in parallel to equalize the load and maintain the frequency close to the frequency target value. Becomes As described above in detail, according to the frequency control apparatus for a turbine generator of the present invention, the frequency is controlled to be constant even when the power load of the turbine generator operating in parallel changes. The load is controlled so that the loads of the turbine generators that generate power by operating in parallel are equalized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a system diagram of a frequency control device of a turbine generator as one embodiment of the present invention. FIG. 2 is an explanatory view of the operation. FIG. 3 is a system diagram of a conventional frequency control device for a turbine generator. FIG. 4 is an explanatory view of the operation. FIG. 5 is an explanatory view of the operation. [Description of Signs] 01 First turbine generator 02, second turbine generator 1, 1a Frequency controller 1A (frequency) correction control signal 2, 2a Frequency setter 2A Correction frequency setting value (signal) 3 Frequency target value setting Unit 4 frequency corrector 5 load corrector 6 average load calculator 7 adder 8 divider 11 frequency detector 12 load detector 13 turbine control valve f ₀ frequency target value (signal) f ₁ output of frequency detector (detection frequency ) L ₁ load L _m average load

Claims (1)

(57) [Claims 1] In a power plant in which a plurality of turbine generators are connected in parallel, each of the turbine generators includes a turbine control valve, a frequency setting device, a frequency detector, and Each of the turbine generators includes a load detector provided with a P-control frequency controller that receives a respective output of the frequency setter and the frequency detector and outputs a correction control signal to the turbine control valve. One average load calculator for calculating an average load from the output of each load detector and the number of the turbine generators is provided, and each of the turbine generators includes the average load calculator and the turbine generator. A load corrector that receives an output of the load detector and sends a load correction signal to the frequency setting device of the turbine generator; and a frequency target of the turbine generator. A frequency corrector that receives a signal and an output of the frequency detector and sends a frequency correction signal to the frequency setter of the turbine generator, wherein the frequency setter includes the load correction signal of the turbine generator and the load correction signal. A frequency control device for a turbine generator, which is configured to output a correction frequency set value signal corresponding to a frequency correction signal.