CN103066627B - The control method of the synchronous generator system that is incorporated into the power networks of active power can be regulated under rotating speed pattern - Google Patents

Abstract

The present invention relates to electric automatic control field, system includes synchronous generator, asynchronous motor and shaft coupling, and described synchronous generator is fixing connects electrical network, also includes converter and controller；Synchronous generator and asynchronous motor are mechanically connected by shaft coupling, and controller connects asynchronous motor by converter；Its control method comprises the following steps: when a, synchronous generator unit operation, and controller sets converter and operates under rotating speed pattern, and sets converter output frequency；B, obtain stator voltage and the stator current of synchronous generator by A/D sampling；C, by controller computing, set the output frequency of converter and carry out regulator generator and be transported to the active power of electrical network；The active power of output of d, in the controller calculated synchronous generator according to calculated active power of output feedback regulation converter output frequency.The synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern provided by the invention, varies without the operational mode of converter, is accurately controlled synchronous generator and is transported to the active power of electrical network when being incorporated into the power networks so that control simple effectively.

Description

The control method of the synchronous generator system that is incorporated into the power networks of active power can be regulated under rotating speed pattern

Technical field

The present invention relates to electric automatic control field, particularly the control method of a kind of synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern.

Background technology

When synchronous generator unit operation, controller sets converter and operates under rotating speed pattern, and set converter output frequency as 50HZ, when synchronous generator by unit operation to when being incorporated into the power networks, due to some converter immutable control model in running, so converter is still operated in the active power of output that cannot regulate synchronous generator under rotating speed pattern.

Summary of the invention

Be incorporated into the power networks synchronous generator system and the control method thereof that can regulate active power under rotating speed pattern provided by the invention, its object is to solve synchronous generator system by unit operation to when being incorporated into the power networks, the problem that converter can not be switched to torque mode by rotating speed pattern.

The technical scheme is that and be achieved in that: the synchronous generator system that is incorporated into the power networks of active power can be regulated under rotating speed pattern, including synchronous generator, asynchronous motor and shaft coupling, described synchronous generator is fixing connects electrical network, also includes converter and controller；Synchronous generator and asynchronous motor are mechanically connected by shaft coupling, and controller connects asynchronous motor by converter.

The control method of the synchronous generator system that is incorporated into the power networks of active power can be regulated under rotating speed pattern, comprise the following steps:

When a, synchronous generator unit operation, controller sets converter and operates under rotating speed pattern, and sets converter output frequency；

B, obtain stator voltage and the stator current of synchronous generator by A/D sampling；

C, by controller computing, set the output frequency of converter and regulate synchronous generator and be transported to the active power of electrical network；

The active power of output of d, in the controller calculated synchronous generator according to calculated active power of output feedback regulation converter output frequency.

Further, described converter is connected with the three-phase input of asynchronous motor by three-phase output.

Described controller includes signal processing module and computing module.

Further, described controller also includes rotating speed mode unit.

Described converter includes output speed, and described output speed is electrically connected with rotating speed mode unit.

Also including sampling unit, described sampling unit includes current sampling unit and voltage sampling unit.

Be incorporated into the power networks synchronous generator system and the control method thereof that can regulate active power under rotating speed pattern provided by the invention, vary without the operational mode of converter, it is accurately controlled synchronous generator and is transported to the active power of electrical network when being incorporated into the power networks so that control simple effective.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, the accompanying drawing used required in embodiment or description of the prior art will be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1: module diagram of the present invention；

Fig. 2: control flow chart of the present invention；

Fig. 3: the present invention regulates flow chart.

In figure: 1, synchronous generator；2, shaft coupling；3, asynchronous motor；4, converter；5, current sampling unit；6, controller.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of protection of the invention.

The synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern provided by the invention, including synchronous generator 1, asynchronous motor 3 and shaft coupling 2, described synchronous generator 1 is fixing connects electrical network, also includes converter 4 and controller 6；Synchronous generator 1 and asynchronous motor 3 are mechanically connected by shaft coupling 2, and controller 6 connects asynchronous motor 3 by converter 4.

The control method of the synchronous generator system that is incorporated into the power networks of active power can be regulated under rotating speed pattern, comprise the following steps:

When a, synchronous generator 1 unit operation, controller 6 sets converter 4 and operates under rotating speed pattern, and sets converter 4 output frequency；

B, obtain stator voltage and the stator current of synchronous generator 1 by A/D sampling；

C, by controller 6 computing, set the output frequency of converter 4 and regulate synchronous generator 1 and be transported to the active power of electrical network；

D, in controller 6 calculated synchronous generator 1 active power of output and according to calculated active power of output feedback regulation converter 4 output frequency.

Further, described converter 4 is connected with the three-phase input of asynchronous motor 3 by three-phase output.Described controller 6 includes signal processing module and computing module.Further, described controller 6 also includes rotating speed mode unit and torque mode unit.Described converter 4 includes output speed, and described output speed is electrically connected with rotating speed mode unit.Also including sampling unit, described sampling unit includes current sampling unit 5 and voltage sampling unit.

When synchronous generator 1 unit operation, controller 6 sets converter 4 and operates under rotating speed pattern, and set converter 4 output frequency as 50HZ, when synchronous generator 1 by unit operation to when being incorporated into the power networks, due to some converter 4 immutable control model in running, so converter 4 is operated in the active power of output that cannot regulate synchronous generator 1 under rotating speed pattern, regulates synchronous generator 1 by the output frequency of controller 6 computing setting converter 4 and be transported to the active power of electrical network.

Specific algorithm is as follows: shown in control flow chart as of the present invention in Fig. 2, and controller obtains the stator voltage U of synchronous generator 1 by A/D sampling_ab、U_bcWith stator current I_a、I_b、I_cAnd obtain U by calculating in controller 6_ca, then to stator voltage U_ab、U_bc、U_caCarry out phase-locked computing, obtain stator phase voltage phase theta, then with stator phase voltage phase theta for benchmark, to stator voltage U_ab、U_bc、U_caWith stator current I_a、I_b、I_cCarry out Clarke and Park conversion, obtain U_d、U_qAnd I_d、I_q:

$\left[\begin{array}{c}{U}_d\\ U_q\end{array}\right]=\frac{\sqrt{2}}{3}\left[\begin{array}{cc}\cos \mathrm{\θ}& \sin \mathrm{\θ}\\ -\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& -\frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}{U}_{\mathrm{ab}}\\ U_{\mathrm{bc}}\\ U_{\mathrm{ca}}\end{array}\right]$

$\left[\begin{array}{c}{I}_d\\ I_q\end{array}\right]=\frac{\sqrt{2}}{3}\left[\begin{array}{cc}\cos \mathrm{\θ}& \sin \mathrm{\θ}\\ -\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& -\frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}{I}_a\\ I_b\\ I_c\end{array}\right]$

Then the active power of output P of synchronous generator 1 is calculated_out=U_d*I_d+U_q*I_q, P_outWith reference active-power P_refMake comparisons and obtain the reference frequency f of converter through PI controller computing_ref, the parameter suitably adjusting PI controller just can control the active power of output of synchronous generator 1 equal to reference to active power.

Voltage acquisition is the voltage scale down that synchronous generator 1 is sent by the electric resistance partial pressure passed through, then the voltage after this being reduced enters A/D conversion chip after carrying out level lifting, filtering and converts digital signal to, collect these digital signals by FPGA and carry out phase-locked, then the digital quantity of voltage after the phase place locked and conversion is passed in real time DSP and carries out coordinate transform and calculate the U of now synchronous generator 1 output voltage simultaneously_d、U_qComponent.

Current acquisition is to utilize current sensor to be reduced by electric current then to allow the electric current after reducing through parallel resistance, a pressure reduction is now formed at the two ends of resistance, it is converted to the digital quantity of voltage signal through A/D by gathering this voltage signal, ratio according to conversion can extrapolate current value size now according to digital quantity, by FPGA, the digital quantity after conversion is passed to DSP, obtain I now through coordinate transform_d、I_q。

As Fig. 3 present invention regulates shown in flow chart, in dsp by calculating U_d*I_d+U_q*I_qObtain synchronous generator 1 active power of output P now_out.When 1 one active-power Ps of given synchronous generator_refTime, now P_outWith P_refDifference is not zero, and is regulated the value f of one control converter 4 output frequency of output by PI_ref, it is achieved controller 6 is according to given active-power P_refChange and constantly change the output frequency of converter 4, but the output frequency of synchronous generator is to be determined by electrical network under grid-connect mode, therefore the output frequency of electromotor cannot change, but the trend changed, the trend of frequency shift can up to the active power of output P of synchronous generator 1_outReach specified value P_refRear just stopping；Once the active-power P set_refChange and P_ref-P_out≠ 0, now controller 6 can change again the output frequency of converter 4 to change synchronous generator 1 output frequency, and synchronous generator 1 exists again the trend of a frequency shift, thus reaching to control the purpose of synchronous generator 1 active power of output.By given suitable K_p、K_iValue can allow converter realize in a little frequency range the large-scale active power regulation of synchronous generator 1.

Be incorporated into the power networks synchronous generator system and the control method thereof that can regulate active power under rotating speed pattern provided by the invention, vary without the operational mode of converter, it is accurately controlled synchronous generator 1 and is transported to the active power of electrical network when being incorporated into the power networks so that control simple effective.

Certainly; when without departing substantially from present invention spirit and essence thereof; those of ordinary skill in the art should make various corresponding change and deformation according to the present invention, but these change accordingly and deformation all should belong to the scope of the claims appended by the present invention.

Claims (5)

1. can regulate the control method of the synchronous generator system that is incorporated into the power networks of active power under rotating speed pattern, it is characterized in that: described system includes: synchronous generator, asynchronous motor and shaft coupling, described synchronous generator is fixing connects electrical network, it is characterised in that: also include converter and controller；Synchronous generator and asynchronous motor are mechanically connected by shaft coupling, and controller connects asynchronous motor by converter；Described controller includes signal processing module and computing module；Its control method comprises the following steps:

When a, synchronous generator unit operation, controller sets converter and operates under rotating speed pattern, and sets converter output frequency；

B, obtain stator voltage and the stator current of synchronous generator by A/D sampling；

C, by controller computing, set the output frequency of converter and regulate synchronous generator and be transported to the active power of electrical network；

The active power of output of d, in the controller calculated synchronous generator according to calculated active power of output feedback regulation converter output frequency.

2. the control method of the synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern according to claim 1, it is characterised in that: described converter is connected with the three-phase input of asynchronous motor by three-phase output.

3. the control method of the synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern according to claim 1, it is characterised in that: described controller also includes rotating speed mode unit.

4. the control method of the synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern according to claim 1, it is characterised in that: described converter includes output speed, and described output speed is electrically connected with rotating speed mode unit.

5. the control method of the synchronous generator system that is incorporated into the power networks that can regulate active power under rotating speed pattern according to claim 1, it is characterised in that: also including sampling unit, described sampling unit includes current sampling unit and voltage sampling unit.