CN101895129A - AC-DC-AC wind power generation cut-in control system - Google Patents

Abstract

The invention relates to an AC-DC-AC wind power generation cut-in control system, belonging to the current technical field. The system comprises a rectifier module, a boosting module and an inversion module, wherein the rectifier module is connected with the boosting module to transmit rectified DC voltage signals, the boosting module is connected with the inversion module to transmit boosted DC voltage signals, and the inversion module outputs power frequency cut-in AC signals. The AC-DC-AC system forms parallel operation with a power grid, no current impact is generated in the cut-in process because of carrying out output control by a frequency transforming device, thereby hardly having effects on the system. The invention has the advantages of simple devices, low cost and easy implementation and can be easily used in actual wind power generation conditions, and practical tests show that the cut-in process is fast and stable and the power quality is good.

Description

AC-DC-AC wind power generation cut-in control system

Technical field

What the present invention relates to is the system in a kind of power technology field, specifically is a kind of AC-DC-AC wind power generation cut-in control system.

Background technology

Along with the world energy sources crisis constantly increases the weight of, the development and use of new forms of energy more and more come into one's own, and wind power generation is as the regenerative resource of environmental protection, and wind-electricity integration system and combination method thereof have very high Practical significance.According to wind-driven generator kind difference, adopt different combination methods.The be incorporated into the power networks method of control of synchronous generator and cage modle induction generator has nothing in common with each other, and the former runs on the synchronous speed that is determined by motor pole number and frequency, and the latter is then with the operation of a little higher than synchronous speed.Hand over the orthogonal grid-connected system by power electronic device, the interchange wind power generation output of instability, frequency conversion rate, low-voltage is changed into the synchronization AC electricity of stable, constant frequency, constant voltage, the purpose that connects, carries with realization wind power generation and existing electrical network.

At present traditional controller major technology problem and shortcoming is, the assembly independent design does not possess and is incorporated into the power networks; Controller adopts has a grade mode to control the solar cell policy; Do not possess totally digitilized DSP technology, digital synchronous Phase Lock Technique, MPPT maximum power point tracking technology (MPPT:Maximum Power Point Trace), anti-islet operation technology, system's centralized management and remote control technology, system component optimization emulation technology.

Through existing literature search is found, Chinese patent application number is: 200310122930.6, name is called: whole integrated net-connected controller of photovoltaic and method, this device is by solar panels, control device, supervising device, composition such as AC load and AC network, solar cell array is connected with the parallel network reverse unit, AC network and AC load interconnect, the output of parallel network reverse unit is connected to the line between AC network and the AC load, host computer and monitoring unit interconnect, monitoring unit and man-machine decoding unit interconnect, and communicate to connect with RS232 interface and human and machine interface unit and host computer.But this device is not handed over the orthogonal conversion, and the impact of being incorporated into the power networks is bigger, and generator and mains frequency are independent, and therefore application limitations is more in the low capacity wind generator system.

Summary of the invention

The objective of the invention is to overcome the above-mentioned deficiency of prior art, a kind of AC-DC-AC wind power generation cut-in control system is provided.The present invention has realized that wind power generation reliably is incorporated into the power networks, and having when being incorporated into the power networks does not have rush of current, and to almost not influence of system, synchronous generator unit operating frequency and mains frequency are independently of one another, and step-out does not take place, can the reactive power adjusting etc. advantage.

The present invention is achieved by the following technical solutions:

The present invention includes: rectification module, boost module and inversion module, wherein: rectification module links to each other transmission through the d. c. voltage signal of rectification with boost module, the boost module d. c. voltage signal of transmission that link to each other with inversion module, but inversion module output power frequency synchronization AC signal through boosting.

Described rectification module is converted to direct current signal with the AC signal of wind-driven generator output, this module comprises: three-phase bridge diode rectification submodule and filtering submodule, wherein: three-phase bridge diode rectification submodule input exchange signal, three-phase bridge diode rectification submodule links to each other with the filtering submodule and transmits direct current signal, and the filtering submodule links to each other with boost module and transmits the low-voltage direct current signal.

Described boost module will be converted to the high-voltage direct-current signal through the low voltage signal of conversion, this module comprises: Boost (switch DC) submodule and the MPPT maximum power point tracking control submodule that boosts, wherein: the Boost submodule transmission low-voltage direct current signal that links to each other with rectification module that boosts, Boost submodule and the MPPT maximum power point tracking control submodule transmission of control signals that links to each other that boosts, the Boost submodule that boosts links to each other with inversion module and transmits the high-voltage direct-current signal.

But described inversion module is converted to power frequency synchronization AC signal with direct current signal, this module comprises: IPM (Intelligent Power Module) submodule and SVPWM (space vector of voltage pulse-width modulation) control submodule, wherein: the IPM submodule links to each other with boost module and transmits the high-voltage direct-current signal, the SVPWM control submodule transmission of control signals that links to each other with the IPM submodule, but the IPM submodule is exported power frequency synchronization AC signal.

Compared with prior art, the invention has the beneficial effects as follows: the system of AC-DC-AC mode and electrical network parallel running do not have rush of current owing to adopt frequency-transposition arrangement to export control when therefore being incorporated into the power networks, to almost not influence of system; By the diode bridge rectification, the IGBT DC chopped-wave is boosted, and the inversion of IPM module will be sent electrical network back to from the electric energy feedback that electrical network obtains, and controlling platform can be simulated the process of permagnetic synchronous motor electricity generation grid-connecting; The diode bridge rectification need not control signal, the efficient height, and the direct current signal that obtains after the filtering is level and smooth; DC chopped-wave adopts classical Boost circuit, and continuous input current drives simple; Inverter adopts the SVPWM inversion of MCU control, the efficient height, and harmonic component is few, and control is simple; The phase place of output signal, harmonic wave, power factor all meet design requirement, the power efficiency height, and the output quality of power supply that is incorporated into the power networks is good, is the ideal platform that permanent magnet synchronous wind generator is incorporated into the power networks.

Embodiment

Below embodiments of the invention are further described: present embodiment is being to implement under the prerequisite with the technical solution of the present invention, provided detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

Embodiment

Present embodiment comprises: rectification module, boost module and inversion module, wherein: wind-driven generator links to each other with rectification module and transmits AC signal, rectification module links to each other transmission through the d. c. voltage signal of rectification with boost module, the boost module d. c. voltage signal of transmission that link to each other with inversion module through boosting, but inversion module links to each other with three phase network by isolating transformer and transmits power frequency synchronization AC signal.

After described rectification module obtains AC signal from wind-driven generator, and be direct current signal with its rectification, it is 430V that controlling platform is imported maximum ac line voltage, its peak value is 608V, this module comprises: three-phase bridge diode rectification submodule and filtering submodule, wherein: three-phase bridge diode rectification submodule input exchange signal, three-phase bridge diode rectification submodule link to each other with the filtering submodule and transmit direct current signal, and the filtering submodule links to each other with boost module and transmits the low-voltage direct current signal.

The SanRexDF100AA160 that three-phase bridge diode rectification submodule adopts in the present embodiment is made up of six power diodes, what the filtering submodule adopted is four filter capacitors, filtering mode in parallel after connecting in twos, wherein the nominal value of single filter capacitor is 3300 μ F, the highest withstand voltage 450V, capacitance group is withstand voltage to be 900V, and total capacity is 3300 μ F.

Described boost module will be converted to the high-voltage direct-current signal through the low voltage signal of conversion, this module comprises: Boost submodule and the MPPT maximum power point tracking control submodule that boosts, wherein: the Boost submodule transmission low-voltage direct current signal that links to each other with the filtering submodule that boosts, Boost submodule and the MPPT maximum power point tracking control submodule transmission of control signals that links to each other that boosts, the Boost submodule that boosts links to each other with inversion module and transmits the high-voltage direct-current signal.

What Boost boosted the submodule employing in the present embodiment is Boost DC chopper circuit classical in the prior art, and wherein: it is 2.5mH that d. c. reactor is selected nominal value, and maximum current is DC28A; Direct current capacitor is selected 2 dc capacitor series connection, and single electric capacity nominal value is 2200 μ F, withstand voltage DC450V, and the capacitance group of formation is withstand voltage to be DC900V, total capacity is 1100 μ F; IGBT (insulated gate bipolar transistor) is the CM100DY-24A type.

But described inversion module is converted to power frequency synchronization AC signal with direct current signal, this module comprises: IPM submodule and SVPWM control submodule, wherein: IPM submodule and the Boost submodule transmission high-voltage direct-current signal that links to each other that boosts, the SVPWM control submodule transmission of control signals that links to each other with the IPM submodule, but the IPM submodule is exported power frequency synchronization AC signal.

That the IPM submodule adopts in the present embodiment is PM75RLA120, and what SVPWM control submodule adopted is SH7047 series HD64F7047F50 type RISC (Reduced Instruction Set Computer, Reduced Instruction Set Computer) microprocessor.

The specified input current of inversion module is 27.5A in the present embodiment, can be similar to the peak current I that thinks by power diode in the rectification module _m, the current effective value I by power diode then _DFor:

$I_D=\sqrt{\frac{1}{2\mathrm{\π}}{\∫}_0^{\frac{2\mathrm{\π}}{3}}{I}_m^2\mathrm{dt}}=\frac{1}{\sqrt{3}}{I}_m=15.9A,$

Diode current rated value IDN is 10.1A.

But three-phase bridge diode rectification submodule repetitive reverse the highest withstand voltage (Repetitive Peak ReverseVoltage) V in the rectification module _RRM=1600V, the maximum average anode current I of three-phase full-wave _D=100A, oppositely maximum leakage electric current (Repetitive Peak Reverse Current) I _RRM(Forward VoltageDrop) V falls in=15mA, forward peak on voltage _FM=1.2V.

Be input as DC200～650V in the boost module, output voltage is DC750V, by gathering the turn-off time T that the input direct voltage value is adjusted IGBT _OffWith the ratio of period T, can obtain the 750V VD.

The withstand voltage of IPM submodule can be determined according to the ac line voltage peak value in the inversion module:

$U=K_U\×\sqrt{2}\×U_{\mathrm{UV}}U=K_U\·\sqrt{2}{\·U}_{\mathrm{UV}},$

Wherein: U _UVBe specified output AC line voltage effective value, get 380V; K _UBe the withstand voltage safety allowance of IPM, value is 1.5～3, works as K _UGot U=1074.8V at 2 o'clock.

The anti-flow valuve of IPM submodule can be determined according to the IPM ac-side current in the inversion module:

$I=K_i\×\sqrt{2}\×i_{\mathrm{\φ}},$

Wherein: i _φBe specified output AC phase current effective value, get 15.5A; K _iBe the safety allowance of the anti-stream of IPM, get 2, be i.e. twice overload situations, I=43.8A.

Present embodiment makes output power factor approach 1 by handing over the orthogonal conversion, and the electric current and voltage harmonic component is few, the electric current and voltage same-phase, and high efficiency, electrical network is not polluted in its output of being incorporated into the power networks, and quality of power supply height is the ideal platform that permanent magnet synchronous wind generator is incorporated into the power networks.

Claims (4)

1. AC-DC-AC wind power generation cut-in control system, it is characterized in that, comprise: rectification module, boost module and inversion module, wherein: rectification module links to each other transmission through the d. c. voltage signal of rectification with boost module, the boost module d. c. voltage signal of transmission that link to each other with inversion module, but inversion module output power frequency synchronization AC signal through boosting.

2. AC-DC-AC wind power generation cut-in control system according to claim 1, it is characterized in that, described rectification module is converted to direct current signal with the AC signal of wind-driven generator output, this module comprises: three-phase bridge diode rectification submodule and filtering submodule, wherein: three-phase bridge diode rectification submodule input exchange signal, three-phase bridge diode rectification submodule links to each other with the filtering submodule and transmits direct current signal, and the filtering submodule links to each other with boost module and transmits the low-voltage direct current signal.

3. AC-DC-AC wind power generation cut-in control system according to claim 1, it is characterized in that, described boost module will be converted to the high-voltage direct-current signal through the low voltage signal of conversion, this module comprises: Boost submodule and the MPPT maximum power point tracking control submodule that boosts, wherein: the Boost submodule transmission low-voltage direct current signal that links to each other with rectification module that boosts, Boost submodule and the MPPT maximum power point tracking control submodule transmission of control signals that links to each other that boosts, the Boost submodule that boosts links to each other with inversion module and transmits the high-voltage direct-current signal.

4. AC-DC-AC wind power generation cut-in control system according to claim 1, it is characterized in that, but described inversion module is converted to power frequency synchronization AC signal with direct current signal, this module comprises: IPM submodule and SVPWM control submodule, wherein: the IPM submodule links to each other with boost module and transmits the high-voltage direct-current signal, the SVPWM control submodule transmission of control signals that links to each other with the IPM submodule, but the IPM submodule is exported power frequency synchronization AC signal.