CN101277018A - Hyposynchronous damp controller for generating set - Google Patents

Abstract

The present invention relates to a device for controlling the subsynchronous damping control device which comprises the following components: an impulse amount input module (PI) which detects the variation quantity of the angular velocity of the machine end and executes the filtering procession, detects and demodulates the SSO signal of each subsynchronous mode; a control module (CM) which executes respective procession to each mode rotary speed signal and generates a control signal by overlapping; and an analogue quantity output module (AO) which outputs the control signal to the excitation system. The device converts the collected SSO signal to the excitation voltage control signal of the exciting winding through control procession. The corresponding exciting current is generated through the exciting winding. The electrical torque under the subsynchronous frequency is formed. The subsynchronous oscillation is functioned with an inhibition action to the subsynchronous oscillation through the torque.

Description

Hyposynchronous damp controller for generating set

Technical field

The present invention relates to electric power system, big power station, need turbo generator set, hydraulic generator unit or have the inhibition of sub-synchronous oscillation of other units of excitation equipment to use, relate in particular to the subsynchronous damping control apparatus of a kind of generating set.

Background technology

Along with development of electric power industry, big capacity power source and long distance power transmission technology are more and more used.In order to save transmission of electricity corridor and construction investment, high power station improves conveying capacity to the more and more Series Compensation that adopt of regional power grid power supply at a distance.On the other hand, DC transmission system is used widely in China, and alternating current-direct current mixes technology of transmission of electricity is becoming the main high voltage electric power transmission network that system, Central China, south electric network are sent in Three Gorges.Mix when technology of transmission of electricity uses at Series Compensation and alternating current-direct current, (frequency is in that 2Hz～48Hz) oscillation problem becomes the new problem and the new focus of harm electrical network and generating set security of operation because that LC resonance and power electronics non-linear element cause is subsynchronous.How increasing that control measure and control appliance reduce and even eliminating sub-synchronous oscillation is one of great technical task of current power industry to the harm in electrical network and power plant.

In generating set stable operation process, the Mechanical Driven moment of torsion of steam turbine and the electromagnetic braking moment of torsion of generator keep balance.When the generator electric disturbance, disequilibrium between Steam Turbine Driven torque and the generator electromagnetic braking torque causes the Mechatronic Systems coupling.Subsynchronous resonance is a kind of self oscillating regime of Mechatronic Systems, and promptly electrical network carries out energy exchange with turbo generator being lower than under one or several frequency of system synchronization frequency.If the electrical oscillation frequency of electrical network is f _e, the synchronizing frequency of electrical network is f _N, axle is that certain rank torsional oscillation natural frequency of mechanical system is f _mIf f _m=f _N-f _e, the oscillatory regime of negative damping will appear in electrical system, and axle is a frequency f _mThe amplitude of pairing principal mode will amplify gradually, finally make the rotor damage, even cause and ruin machine.

The main cause that subsynchronous dynamo-electric resonance produces is to interact between induction generator effect, the dynamo-electric moment of torsion and amplifies as the above-mentioned two kinds transient state moments of torsion that act on stack result.Therefore above-mentioned three reasons of eliminating and preventing to produce subsynchronous dynamo-electric resonance are to suppress the subsynchronous dynamo-electric key that resonates.This patent declaration material is introduced the subsynchronous damping control apparatus SSODC of a kind of generating set.Measuring machine end angular velocity varies amount, after it is carried out carrying out the ratio phase shift respectively after bandpass filtering separates, stack input field regulator, the exciting voltage of regulator generator, electric current are to increase the damping to SSO.It is the most direct also most economical with respect to adding block filter or improving schemes such as generator and system configuration to use this scheme inhibition torsional oscillation.

Summary of the invention

The present invention relates to the subsynchronous damping control apparatus of a kind of generating set, can realize the damage of vibrating generator unit shaft system being caused is avoided in the inhibition of the subsynchronous dynamo-electric resonance of generating set.The subsynchronous SSO signal of device by gathering, through control and treatment, change the exciting voltage control signal of excitation winding into, produce corresponding exciting current by excitation winding, form the electromagnetic torque under the subsynchronous frequency, sub-synchronous oscillation is played inhibitory action by this torque.

Realize suppressing the device of shafting torsional vibration of turbo-generator set by producing generator electromagnetic damping moment of torsion, comprising: pulsed quantity input module PI, main control module CM and analog output module AO; Described pulsed quantity input module PI is used for machines end angular velocity varies amount, and obtains subsynchronous mode signal by the filtering link; Described main control module CM is used for the output signal of received pulse amount input module PI and each mode signal is carried out parallel processing respectively, and stack generates control signal again; Described analog output module AO is used to receive the control signal of master control module CM, be translated into the current signal of 4～20mA, thereby and this signal injected generator excited system produce subsynchronous frequency electromagnetism torsional oscillation, realize inhibitory action by this torque of described electromagnetism torsional oscillation that produces to sub-synchronous oscillation.

1, PI module machines end angular velocity varies amount

In this device, adopt the feedback signal of the perunit value of generator shaft speed and rated rotational frequency difference as the subsynchronous damping control apparatus of generating set, be called machine end angular velocity varies amount, ω represents with Δ.

Use the pulse signal of non-contact sensor induction, the pulse signal demodulation is obtained machine end angular velocity varies amount, contain the oscillating component of a plurality of frequencies among the machine end angular velocity varies amount Δ ω with the gear generation of axle rotation.

2, PI module modal filter

Subsynchronous resonance SSO is that the frequency of extrinsic motivated moment of torsion is in step with the intrinsic torsion frequency in certain rank of axle system and is produced resonance, the twisting vibration of main shaft is increased rapidly, thereby cause the fail in shear of main shaft.So, just need suppress to the subsynchronous resonance frequency signal in order to suppress the torsional resonance of steam-electric generating set shafting.This needs earlier machine end angular velocity varies amount Δ ω to be carried out filtering, obtains the corresponding oscillating component of intrinsic torsion frequency with rotor.The filtering link comprises a low pass filter, a high pass filter and the band pass filter that each subsynchronous mode signal is carried out filtering respectively.

The low pass filter function is

$H\left(s\right)=\frac{1}{1+s/{\mathrm{\ω}}_L+{(s/{\mathrm{\ω}}_L)}^2}$

The high pass filter function is

$H\left(s\right)=\frac{{(s/{\mathrm{\ω}}_H)}^2}{1+s/{\mathrm{\ω}}_H+{(s/{\mathrm{\ω}}_H)}^2}$

The band pass filter transfer function is

$H\left(s\right)=\frac{s/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">P</figure-callout>}}}{1+6\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">P</figure-callout>}}^2+{(s/{\mathrm{\&omega;}}_P)}^2}\frac{1+{(s/{\mathrm{\&omega;}}_{B1})}^2}{1+4\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">B</figure-callout>}1}^2+{(s/{\mathrm{\&omega;}}_{B1})}^2}\frac{1+{(s/{\mathrm{\&omega;}}_{B2})}^2}{1+4\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">B</figure-callout>}2}^2+{(s/{\mathrm{\&omega;}}_{B2})}^2}$

After isolating each torsional oscillation mode information, can and then implement independent modal control.

Above filter scheme is at model frequency during by certain measuring errors and fluctuation range, can leach the model frequency signal of being paid close attention to preferably, effectively organize other mode signals and noise to pass through, the phase deviation of generation suitably and when model frequency fluctuates changes not quite.

3, each mode tach signal control and treatment

The ratio phase shift is the key link of decision SSODC control effect, and the SSODC control law is realized by main control module CM.The control law of main control module adopts separates mode control, by the generator actual speed is sampled, filtering, after obtaining the tach signal under the corresponding SSO mode, each mode tach signal is handled respectively, the signal stack after all are handled obtains the SSODC control number.

The realization of control law is divided into following 4 points among the main control module CM:

1), the ratio phase shift of each mode SSO signal is handled.

2), each mode SSO signal carried out the ratio phase shift and handles after, limit value respectively.

To mode one SSO signal, handle by amplitude limit 1 link,

To mode two SSO signals, handle by amplitude limit 2 links,

To mode Three S's SO signal, handle by amplitude limit 3 links,

Wherein, the limit value to each single mode act as optional.

3), each mode SSO signal is carried out superpose after ratio, phase shift, the limit value processing.

The control action of SSODC is to be realized jointly by each mode signal linear superposition.

4), the SSODC signal of stack generation is exported limit value.

4, the self adaptation measure of Control Parameter

The changeable of system operation mode causes some that SSO is had the crucial parameter that influences, and is that mechanical damping, total string benefit degree etc. have bigger mobility scale as axle.

In order to realize the adaptivity of Control Parameter, the relationship characteristic between the damping control effect of holding SSODC and operational mode parameter (unit output, the switching of benefit degree, important line etc. of going here and there) and the corresponding optimal proportion phase shift link parameter.With the ratio phase shift link parameter K of each mode, T1, T2, T3, T4 as definite value, put into the different definite values district of main control module (CM), according to the damping control effect of SSODC and the corresponding relation of operational mode parameter, obtain the ruuning situation information of present unit, automatically switch to corresponding definite value district.

Parameter is through optimal design, can reach: considering under excitation top value, the constraintss such as robustness the influence of conventional excitation function, Control Parameter scope, make the SSODC Control Parameter under the operational mode that is contained, to improve modal damping as far as possible, guarantee that each torsional oscillation mode has enough stability margins.

5, control signal output

Analog output module (AO) output control signal is sent to excitation system, on the original control signal of the field regulator that is added to.

Rectifier bridge excitation system for thyristor control, controlled quentity controlled variable is the switch angle of thyristor, this scheduling is painstakingly changed in the output of SSODC, the control rectifier bridge produces subsynchronous voltage to frequency and electric current on excitation winding, and then form the electromagnetic torque of subsynchronous frequency, the SSO of axle system is played damping action.The additional control signal that SSODC produces can make up in AVR output place or in PSS access place and original control signal according to actual conditions.

The mode torsional vibration signals of turbo generator set can in real time, accurately be measured and demodulate to this device, affacts excitation system by control signal, increases the subsynchronous damping of generating set.Along with large turbo-type generator group and remote large capacity transmission The Application of Technology, the situation that sub-synchronous oscillation SSO takes place in unit and electrical network is more and more serious, and the subsynchronous damping control apparatus of generating set is an effective means that suppresses sub-synchronous oscillation.This device has been realized the control to the subsynchronous damping of generating set, and the sub-synchronous oscillation problem that solves power plant and electrical network is significant.

Description of drawings

Fig. 1 .1, Fig. 1 .2, Fig. 1 .3 have illustrated pulse signal that the machine end sensor is measured and the machine end angular velocity varies amount Δ ω signal that obtains through demodulation, wherein

Fig. 1 .1 is a rotor when doing uniform rotation, the uniform pulse ripple of transducer output;

Fig. 1 .2 is that rotor exists when vibrating, and transducer is output as the impulse wave of density interphase;

Fig. 1 .3 is for to obtain machine end angular velocity varies amount Δ ω with the pulsed quantity demodulation;

Fig. 2 is a PI module mode filtering schematic diagram;

Fig. 3 is that main control module CM control law realizes schematic diagram;

Fig. 4 is a logic diagram of realizing control law among the CM;

Fig. 5 .1, Fig. 5 .2 and Fig. 5 .3 have illustrated to excite torsional oscillation of the unit adding pumping signal, do not apply the SSODC effect, detect the sampled value that demodulation obtains each mode.Wherein

Fig. 5 .1 is mode one machine end angular velocity varies value Δ ω ₁

Fig. 5 .2 is mode two machine end angular velocity varies value Δ ω ₂

Fig. 5 .3 is mode three machine end angular velocity varies value Δ ω ₃

Fig. 6 .1, Fig. 6 .2 and Fig. 6 .3 have illustrated to excite torsional oscillation of the unit adding pumping signal, apply the SSODC effect, detect the sampled value that demodulation obtains each mode, wherein

Fig. 6 .1 is mode one machine end angular velocity varies value Δ ω ₁

Fig. 6 .2 is mode two machine end angular velocity varies value Δ ω ₂

Fig. 6 .3 is mode three machine end angular velocity varies value Δ ω ₃

Fig. 7 suppresses the effect comparison schematic diagram for SSODC;

Fig. 8 is a SSODC apparatus structure schematic diagram;

Fig. 9 is the subsynchronous damping control apparatus wiring schematic diagram of generating set.

Embodiment

Table and embodiment are described in further details the present invention with reference to the accompanying drawings below.

The course of work of this device is: harvester end angular velocity varies amount, access each mode angular velocity varies instantaneous value of machine end by the mode filter solution, and obtain the oscillating component of each torsional oscillation mode.Behind ratio phase shift processing and passage amplitude limit, obtain the control signal of corresponding mode, form total control output after the addition, on the original control signal of the field regulator that is added to behind total amplitude limit, the control rectifier bridge produces subsynchronous voltage to frequency and electric current on excitation winding, and then form the electromagnetic torque of subsynchronous frequency, by this torque sub-synchronous oscillation is played inhibitory action.Apparatus structure installs the practical application wiring as shown in Figure 9 as shown in Figure 8.

1, PI module machines end angular velocity varies amount

Use the pulse signal of non-contact sensor induction with the gear generation of axle rotation.During each tooth process transducer, produce a pulse signal.When rotor was done uniform rotation, burst location had reflected the arrangement position of each tooth on circumference of gear.What transducer was exported is uniform impulse wave, and its fundamental frequency is S*N (S is a speed-frequency, and N is the gear number of teeth), as Fig. 1 .1.

When there was vibration in rotor, variation had taken place in the position of each pulse, and vibration makes pulse signal that phase shift take place, and is output as the impulse wave of density interphase, as Fig. 1 .2.Extract this phase shift, the one group of sampled value that just obtains vibrating, top pulse train has carried the full detail that axle rotatablely moves.

Use following formula, then the pulsed quantity demodulation can be obtained machine end angular velocity varies amount.

100*π*dt+Δω/3000+Δω*dt＝0

Wherein the pulse period that forms for actual measurement gear two between cog of dt and calibration pulse cycle is poor.

Δ ω is machine end angular velocity varies amount.

Obtain the angular velocity varies amount after the impulse wave demodulation shown in Fig. 1 .3.

If during the simple harmonic quantity torsional oscillation of rotor generation single-frequency, the angular displacement in a certain cross section is:

υ(t)＝Asin(ω _tt+θ)

ω in the formula _tBe the angle of throw frequency, A and θ are the amplitude and the initial phase of this section.

If with the rotor of stabilized (steady-state) speed work, when it was subjected to the periodicity driving torque, the torsional oscillation of rotor comprised the simple harmonic quantity component of different frequency and amplitude, at this moment has:

$\mathrm{\&phi;}\left(t\right)={\mathrm{\&omega;}}_{r}t+\underset{k}{\mathrm{\&Sigma;}}{A}_k\sin ({\mathrm{\&omega;}}_{k}t+{\mathrm{\&theta;}}_k)$

The angular speed that axle rotatablely moves is the mean angular velocity of axle and the superposition of torsional oscillation angular speed:

$\mathrm{\&omega;}={\mathrm{\&omega;}}_r+\underset{k}{\mathrm{\&Sigma;}}{A}_k{\mathrm{\&omega;}}_k\cos ({\mathrm{\&omega;}}_{k}t+{\mathrm{\&theta;}}_k)$

Machine end angular velocity varies amount then $\mathrm{\&Delta;\&omega;}=\underset{k}{\mathrm{\&Sigma;}}{A}_k{\mathrm{\&omega;}}_k\cos ({\mathrm{\&omega;}}_{k}t+{\mathrm{\&theta;}}_k)$

ω in the formula _k, A _k, θ _kThe corresponding parameter of representing K oscillating component respectively.

The oscillating component that contains a plurality of frequencies among the machine end angular velocity varies amount Δ ω.

Subsynchronous resonance SSO is that the frequency of extrinsic motivated moment of torsion is in step with the intrinsic torsion frequency in certain rank of axle system and is produced resonance, the twisting vibration of main shaft is increased rapidly, thereby cause the fail in shear of main shaft.So, just need suppress to the subsynchronous resonance frequency signal in order to suppress the torsional resonance of steam-electric generating set shafting.This needs earlier machine end angular velocity varies amount Δ ω to be carried out filtering, obtains the corresponding oscillating component of intrinsic torsion frequency with rotor.

4, PI module modal filter

Getting a machine end angular velocity varies amount that rotatablely moves by 1 is

$\mathrm{\&Delta;\&omega;}=\underset{k}{\mathrm{\&Sigma;}}{A}_k{\mathrm{\&omega;}}_k\cos ({\mathrm{\&omega;}}_{k}t+{\mathrm{\&theta;}}_k)$

For multi-modal SSO, adopt modal filter from Δ ω signal, to isolate each torsional oscillation mode information, filter is as shown in Figure 2.Wherein

The low pass filter function is

$H\left(s\right)=\frac{1}{1+s/{\mathrm{\&omega;}}_L+{(s/{\mathrm{\&omega;}}_L)}^2}$

The high pass filter function is

$H\left(s\right)=\frac{{(s/{\mathrm{\&omega;}}_H)}^2}{1+s/{\mathrm{\&omega;}}_H+{(s/{\mathrm{\&omega;}}_H)}^2}$

The band pass filter transfer function is

$H\left(s\right)=\frac{s/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">P</figure-callout>}}}{1+6\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">P</figure-callout>}}^2+{(s/{\mathrm{\&omega;}}_P)}^2}\frac{1+{(s/{\mathrm{\&omega;}}_{B1})}^2}{1+4\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">B</figure-callout>}1}^2+{(s/{\mathrm{\&omega;}}_{B1})}^2}\frac{1+{(s/{\mathrm{\&omega;}}_{B2})}^2}{1+4\mathrm{\&pi;s}/{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">B</figure-callout>}2}^2+{(s/{\mathrm{\&omega;}}_{B2})}^2}$

After isolating each torsional oscillation mode information, can and then implement independent modal control.

Above filter scheme is at model frequency during by certain measuring errors and fluctuation range, can leach the model frequency signal of being paid close attention to preferably, effectively organize other mode signals and noise to pass through, the phase deviation of generation suitably and when model frequency fluctuates changes not quite.

5, each mode tach signal control and treatment

The ratio phase shift is the key link of decision SSODC control effect, and the SSODC control law is realized by main control module (CM).The control law of main control module adopts separates mode control, by the generator actual speed is sampled, filtering, after obtaining the tach signal under the corresponding SSO mode, each mode tach signal is handled respectively, the signal stack after all are handled obtains the SSODC control number.As shown in Figure 3.

The realization of control law is divided into following 4 points among the CM:

1), the ratio phase shift of each mode SSO signal is handled.

Gain/phase shift link transfer function is

$H\left(s\right)=k\left(\frac{1+T_1\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">s</figure-callout>}}{1+T_{2}s}\right)\left(\frac{1+T_3\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20081005703900142.png,A20081005703900151.png"\; state="\{\{state\}\}">s</figure-callout>}}{1+T_{4}s}\right)$

To mode one angular velocity varies amount Δ ω 1, handle by gain/phase shift link 1,

To mode two angular velocity varies amount Δ ω 2, handle by gain/phase shift link 2,

To mode triangle velocity variable Δ 3, handle by gain/phase shift link 3,

Wherein: K is a proportionality coefficient

T1 is the leading time constant

T3 is the leading time constant

T2 is a lag time constant

T4 is a lag time constant

2), each mode SSO signal carried out the ratio phase shift and handles after, limit value respectively.

To mode one SSO signal, handle by amplitude limit 1 link,

To mode two SSO signals, handle by amplitude limit 2 links,

To mode Three S's SO signal, handle by amplitude limit 3 links,

Wherein, the limit value to each single mode act as optional.

3), each mode SSO signal is carried out superpose after ratio, phase shift, the limit value processing.

The control action of SSODC is to be realized jointly by each mode signal linear superposition.

4), the SSODC signal of stack generation is exported limit value.

4, the self adaptation measure of Control Parameter

The changeable of system operation mode causes some that SSO is had the crucial parameter that influences, and is that mechanical damping, total string benefit degree etc. have bigger mobility scale as axle.

In order to realize the adaptivity of Control Parameter, the relationship characteristic between the damping control effect of holding SSODC and operational mode parameter (unit output, the switching of benefit degree, important line etc. of going here and there) and the corresponding optimal proportion phase shift link parameter.With the ratio phase shift link parameter K of each mode, T1, T2, T3, T4 as definite value, put into the different definite values district of main control module (CM), according to the damping control effect of SSODC and the corresponding relation of operational mode parameter, obtain the ruuning situation information of present unit, automatically switch to corresponding definite value district.

Parameter is through optimal design, can reach: considering under excitation top value, the constraintss such as robustness the influence of conventional excitation function, Control Parameter scope, make the SSODC Control Parameter under the operational mode that is contained, to improve modal damping as far as possible, guarantee that each torsional oscillation mode has enough stability margins.

6, control signal output

Analog output module (AO) output control signal is sent to excitation system, on the original control signal of the field regulator that is added to.

Rectifier bridge excitation system for thyristor control, controlled quentity controlled variable is the switch angle of thyristor, this scheduling is painstakingly changed in the output of SSODC, the control rectifier bridge produces subsynchronous voltage to frequency and electric current on excitation winding, and then form the electromagnetic torque of subsynchronous frequency, the SSO of axle system is played damping action.The additional control signal that SSODC produces can make up in AVR output place or in PSS access place and original control signal according to actual conditions.

With domestic certain 600MW of power plant turbo generator set is example.

Known turbo generator set Mechatronic Systems characteristic frequency is as follows:

Mode 1	Mode 2	Mode 3
			15.2HZ	26.1HZ	30.2HZ

PI module harvester end angular velocity varies value Δ ω through mode filtering, obtains three subsynchronous mode Δ ω ₁, Δ ω ₂, Δ ω ₃

The mode filtering as shown in Figure 2,

The low pass filter parameter is set to: ω _L=2 π 40

The high pass filter parameter is set to: ω _H=2 π 10

The parameter of band pass filter 1 is set to: ω _P=2 π 16, ω _B1=2 π 26, ω _B2=2 π 30

The parameter of band pass filter 2 is set to: ω _P=2 π 26, ω _B1=2 π 16, ω _B2=2 π 30

The parameter of band pass filter 3 is set to: ω _P=2 π 30, ω _B1=2 π 16, ω _B2=2 π 26

Be the inhibition effect of checking SSODC, system adds a pumping signal to the Steam Turbine axle, makes it produce sub-synchronous oscillation, does not apply the SSODC control action.Pumping signal is 26.1HZ, and amplitude is equivalent to 30% rated excitation voltage, duration 10s.After PI module detection filter, the angular velocity varies value that obtains three mode is shown in Fig. 5 .1, Fig. 5 .2, Fig. 5 .3.Wherein Fig. 5 .1 is mode one Δ ω ₁Sampled value; Fig. 5 .2 is mode two Δ ω ₂Sampled value; Fig. 5 .3 is mode three Δ ω ₃Sampled value; Abscissa is the time, and be 60S writing time.Ordinate is the perunit value of angular velocity varies value.As seen from the figure, 26.1HZ mode torsional vibration signals amplitude maximum, other two mode torsional vibration signals can be ignored substantially.

After the oscillating component process ratio phase shift processing and passage amplitude limit with each torsional oscillation mode, obtain the control signal of corresponding mode, the control law schematic diagram as shown in Figure 3.Fig. 4 is a logic diagram of realizing control law in the main control module (CM).Wherein

The parameter of ratio/phase shift 1 is set to: k=120, T1=T3=-0.01928, T2=T4=0.01928

The parameter of ratio/phase shift 2 is set to: k=-200, T1=T3=-0.002852, T2=T4=0.002852

The parameter of ratio/phase shift 3 is set to: k=150, T1=T3=-0.01270, T2=T4=0.01270

System adds a pumping signal to the Steam Turbine axle, makes it produce sub-synchronous oscillation, applies the SSODC control action simultaneously.Pumping signal is 26.1HZ, and amplitude is equivalent to 30% rated excitation voltage, duration 10s.Pumping signal finishes the control action that the back adds SSODC, and duration 10s. is after PI module detection filter, and the angular velocity varies value that obtains three mode is shown in Fig. 6 .1, Fig. 6 .2, Fig. 6 .3.Wherein Fig. 6 .1 is mode one Δ ω ₁Sampled value; Fig. 6 .2 is mode two Δ ω ₂Sampled value; Fig. 6 .3 is mode three Δ ω ₃Sampled value; Abscissa is the time, and be 60S writing time.Ordinate is the perunit value of angular velocity varies value.

Because the outer energizing signal that applies is 26.1HZ, 26.1HZ mode torsional vibration signals amplitude maximum, other two mode torsional vibration signals can be ignored substantially.So put aside mode one, mode three, contrast and applied after the control action inhibition effect of mode two 26.1HZ before applying the SSODC control action.As shown in Figure 7.Can find out obviously that the convergence that Δ ω value envelope of curve line that SSODC does the time spent is arranged than the Δ ω value envelope of curve line that does not have SSODC and do the time spent is good, promptly the inhibition of shafting torsional oscillation is effective.

By above execution mode, the present invention can in real time, accurately measure and demodulate the mode torsional vibration signals of turbo generator set as can be known, affacts excitation system by control signal, increases the subsynchronous damping of generating set.Along with large turbo-type generator group and remote large capacity transmission The Application of Technology, the situation that sub-synchronous oscillation SSO takes place in unit and electrical network is more and more serious, and the subsynchronous damping control apparatus of generating set is an effective means that suppresses sub-synchronous oscillation.This device has been realized the control to the subsynchronous damping of generating set, and the sub-synchronous oscillation problem that solves power plant and electrical network is significant.

Claims (6)

1, a kind of by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, comprising: a pulsed quantity input module (PI), a main control module (CM) and analog output module (AO); It is characterized by,

Described pulsed quantity input module (PI) is used for machines end angular velocity varies amount, and obtains subsynchronous mode signal by the filtering link;

Described main control module (CM) is used for the output signal of received pulse amount input module (PI) and each mode signal is carried out parallel processing respectively, and stack generates control signal again;

Described analog output module (AO) is used to receive the control signal of master control module (CM), be translated into the current signal of 4～20mA, thereby and this signal injected generator excited system produce subsynchronous frequency electromagnetism torsional oscillation, realize inhibitory action by this torque of described electromagnetism torsional oscillation that produces to sub-synchronous oscillation.

2, according to claim 1 by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, it is characterized by, adopt the feedback signal of the perunit value of generator shaft speed and rated rotational frequency difference as the subsynchronous damping control apparatus of generating set, be called machine end angular velocity varies amount, ω represents with Δ, the process of described pulsed quantity input module (PI) machines end angular velocity varies amount Δ ω adopts noncontact to survey the tooth principle, and the pulse signal of transducer is demodulated into the torsional angle displacement signal.

3, according to claim 1 by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, the filtering link of said pulsed quantity input module (PI) comprises a low pass filter, a high pass filter and the band pass filter that each subsynchronous mode signal is carried out filtering respectively.

4, according to claim 1 by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, in master control module (CM), described each mode signal is handled respectively is by gain/phase shift link each mode signal to be carried out the ratio phase shift respectively to handle, wherein, but the Control Parameter online modification of ratio phase shift has adaptivity.

5, according to claim 1 by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, in master control module (CM), the value that each mode signal carries out respectively obtaining after the ratio phase shift is handled is carried out linear superposition, and the signal after the stack is carried out high-low limits handle, generate the SSODC control signal.

6, according to claim 1 by producing the device that the realization of generator electromagnetic damping moment of torsion suppresses shafting torsional vibration of turbo-generator set, it is characterized by, described analog output module (AO) output control signal is sent to excitation system, be added on the original control signal of field regulator, rectifier bridge excitation system for thyristor control, controlled quentity controlled variable is the switch angle of thyristor, this scheduling is changed in the output of SSODC control signal, the control rectifier bridge produces subsynchronous voltage to frequency and electric current on excitation winding, and then form the electromagnetic torque of subsynchronous frequency, SSO to axle system plays damping action, and sub-synchronous oscillation is played inhibitory action.

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