simulink仿真演示外文翻譯

1、<p><b>　　英文原文</b></p><p>　　Simulink Demos</p><p>　　Simulink is a tool for modeling, analyzing, and simulating physical and mathematical systems, including those with nonlinear e

2、lements and those that make use of continuous and discrete time.</p><p>　　As an extension of MATLAB, Simulink adds many features specific to dynamic systems while retaining all of general purpose functionali

3、ty of MATLAB.</p><p>　　Run demos in the following categories to see Simulink in action.</p><p>　　Other Simulink Products</p><p>　　Run demos for other Simulink products you have inst

4、alled. Try these demos to see which Simulink products might be appropriate for the work you do. Note that this is a comprehensive list of Simulink products. Your particular installation of MathWorks products will likely

5、include only some of these products.</p><p><b>　　See Also</b></p><p>　　In the Contents pane, for each Simulink product, see documentation Examples to view more sample code you can ru

6、n or copy.</p><p>　　Three-phase Three-level PWM Converter (discrete)</p><p>　　This demonstration illustrates simulation of a 3-phase, 3-level inverterand Discrete 3-phase PWM Generator. It also

7、demonstrates harmonic analysis of PWM waveforms using the Powergui/FFT tool. </p><p>　　Circuit Description

8、 </p><p>　　The

9、 system consists of two three-phase three-level PWM voltage source converters connected in twin configuration。The inverter feeds an AC load (1kW, 500 var 60Hz 208 Vrms) through a three-phase transformer.</p><

10、;p>　　Harmonic filtering is performed by the transformer leakage inductance (8%) and load capacitance (500 var).Each of the two inverters uses the Three-Level Bridge block where the specified power electronic devices a

11、re IGBT/Diode pairs.Each arm consists of 4 IGBTs, 4 antiparallel diodes, and 2 neutral clamping diodes.The inverter is controlled in open loop. Pulses are generated by the Discrete 3-Phase Discrete PWM Generator block. T

12、his block is available in theExtras/Discrete Control Blocks library.</p><p>　　When operating in synchronized mode, the carrier triangular signal is synchronized on a PLL reference angle connected to input &#

13、39;wt'.In synchronized mode, the carrier chopping frequency is specified by the switching ratio as a multiple of the output frequency.Three sinusoidal 0.85 pu modulating signals are provided by the 'Discrete 3-ph

14、ase Programmable Source' to obtain a modulation index of 0.85.The carrier signals are synchronized on the modulating signals. in the PWM Generator block, you can </p><p>　　Demonstration</p><p

15、>　　Run the simulation and observe the following three waveforms on the Scope block:</p><p>　　Phase-neutral voltage Van_inv1 generated by inverter 1 (trace 1), phase A voltage Vaa_inverter generated by th

16、e twin inverter (trace 2) andphase-phase load voltage Vab_load (trace 3). The Van_inv1 waveform cleary demonstrates the three levels: +200 V, 0 V, and -200 V.Once the simulation is completed, open the Powergui and sele

17、ct 'FFT Analysis' to display the 0 - 5000 Hz frequency spectrum of signals saved in the 'psb3phPWM3level_str' structure. The FFT will be performed on a 2-cycle window </p><p>　　DC/DC and DC

18、/AC PWM Converters (discrete)</p><p>　　This demonstration illustrates use of the Universal Bridge andDiscrete PWM Pulse Generator blocks. It also demonstrates harmonic analysis of PWM waveforms using the Pow

19、ergui/FFT tool. </p><p>　　Circuit Description</p><p>　　The system consists of three independant circuits illustrating various PWM DC/DC and DC/AC inverters.All converters are controlled in open

20、loop with the Discrete PWM Generator block available in the Extras/Discrete Control Blocks library.</p><p>　　The three circuits use the same DC voltage (Vdc = 400V), carrier frequency (1080 Hz) and modulatio

21、n index (m = 0.8) .From top to bottom, the three circuits are:</p><p>　　1. DC/DC, two-quadrant converter (one-arm; two-switches)</p><p>　　2. DC/AC, bipolar converter (one-arm; two-switches)<

22、;/p><p>　　3. DC/AC, monopolar converter (two-arms; four-switches)</p><p>　　In order to allow further signal processing, signals displayed on the three Scope blocks (sampled at simulation sampling

23、rate of 3240 samples/cycle)are stored in three variables named 'psb1phPWM1_str' , 'psb1phPWM2_str' and 'psb1phPWM3_str' (structures with time).</p><p>　　Demonstration</p>&

24、lt;p>　　Run the simulation and observe the following two waveforms on the Scope blocks:</p><p>　　current into the load (trace 1), voltage generated by the PWM inverter (trace 2). </p><p>　　Onc

25、e the simulation is completed, open the Powergui and select 'FFT Analysis' to display the 0 - 5000 Hz frequency spectrum of signals saved in the three 'psb1phPWMx_str' structures. The FFT will be perform

26、ed on a 2-cycle window starting at t = 0.1 - 2/60 (last 2 cycles of recording). For each circuit selelect Input labeled 'V inverter' . Click on Display and observe the frequency spectrum of last 2 cycles.The fun

27、damental component of V inverter (DC component in case of circuit 1) is displaye</p><p>　　Compare also the harmonic contents in the inverter voltage for the two-switch and four-switch DC/AC inverters.</p

28、><p>　　For the two-switch inverter, the first harmonics occur around the carrier frequency (1080 Hz +- k*60 Hz, with a maximum of 103% at 1080 Hz ),</p><p>　　whereas for the four-switch inverter

29、harmonics are lower and appear at double of carrier frequency (maximum of 40% at 2*1080+-60 Hz).As a result, the current is "cleaner" for the four-switch inverter.</p><p>　　If you now perform a FFT

30、 on the signal Iload you will notice that the THD of load current is 7.3% for the two-switch inverter as compared toonly 2% for the four-switch inverter。</p><p>　　Circuit Description</p><p>　　A

31、 three-phase motor rated 3 HP, 220 V, 1725 rpm is fed by a sinusoidal PWM inverter. The base frequencyof the sinusoidal reference wave is 60 Hz while the triangular carrier wave's frequency is set to 1980 Hz. <

32、;/p><p>　　The PWM inverter is built entirely with standard Simulink blocks. Its output goes through Controlled Voltage Source blocks before being applied to the Asynchronous Machine block's stator windings.

33、 The machine's rotor is short-circuited. Its stator leakage inductance Lls is set to twice its actual value to simulate the effect of a smoothing reactor placed between the inverter and the machine. The load torque a

34、pplied to the machine's shaft is constant and set to its nominal value of 11.9 N.m. </p><p>　　The motor is started from stall. The speed setpoint is set to 1.0 pu, or 1725 rpm. This speed is reached

35、after 0.9 s.</p><p>　　Demonstration</p><p>　　Take a look at the simulation parameters. The Maximum time step has been limited to 10 microseconds.</p><p>　　This is required due to th

36、e relatively high switching frequency (1980 Hz) of the inverter. </p><p>　　Observe that the rotor and stator currents are quite "noisy," despite the use of a smoothi

37、ng reactor. The noise introduced by the PWM inverter is also observed in the electromagnetic torque waveform Te. However, the motor's inertia prevents this noise from appearing in the motor's speed waveform.

38、 </p><p>　　The RMS value of the fundamental component of the line voltage at the machine's stator terminals is extracted with a Fourier block, which can be found in t

39、he Measurements group of the Extras library. </p><p>　　Finally, observe the PWM inverter's output. Use the zoom on the vab oscilloscope to zoom in on the waveform.</p>

40、<p>　　Simple 6-pulse HVDC Transmission System (discrete)</p><p>　　This demonstration illustrates steady-state and transient performance</p><p>　　of a simple 500 MW (250 kV-2kA) HVDC trans

41、mission system</p><p>　　CIRCUIT DESCRIPTION</p><p>　　A 500 MW (250 kV, 2 kA) DC linterconnexion is used to transmit power from a 315 kV, 5000 MVA AC network. The network is simulated by a LLR d

42、amped equivalent (impedance angle of 80 degrees at 60 Hz and 3rd harmonic). The converter transformer and the rectifier are modelled respectively with the Universal Transformer and Universal Bridge blocks The converter

43、is a 6-pulse rectifier. It is connected to a 300 km distributed parameter line through a 0.5 H smoothing reactor LsR.The inverter is simulat</p><p>　　Voltages sent to the synchronization system are filtered

44、by 2nd order band pass filters. The whole control system is discretized (Sample time = 1/360/64 = 43.4 us).THe DC line current at the output of the rectifier is compared with a reference. The PI regulator tries to keep t

45、he error at zero and outputs the alpha firing angle requiredby the synchronizing unit. Inputs 3 and 4 of the current regulator allow to bypass the regulator action and to impose the alpha firing angle </p><p&g

46、t;　　DEMONSTRATION</p><p>　　Notice that the system is discretized (sample time 1/360/64 = 43.4 us). Setting, the sample time in to zero, will change to continuous integration for the power system .The system

47、is programmed to start and reach a steady state. Then, a step is applied on the reference current to observe the dynamic response of the regulator.Finally a DC fault is applied on the line. Start the simulation and obs

48、erve the following events on Scope1 : </p><p>　　0 < t < 0.3 s</p><p>　　Trace 1 shows the the reference current (magenta) and the measured Id current (yellow). The reference current is set

49、 to 0.5 pu (1 kA). The DC current starts from zeroand reaches a steady-state in 0.1 s. Trace 2 shows the alpha firing angle required to obtain 0.5 pu of current (30 degrees).</p><p>　　0.3 < t < 0.5 sAt

50、 t = 0.3 s, the reference current is increased from 0.5 pu (1 kA) to the nominal current 1pu (2 kA). The current regulator responds in approximately 0.1 s (6 cycles).The alpha angle decreases from 30 degrees to 15 deg

51、rees.</p><p>　　0.5 < t < 0.55 s</p><p>　　At t = 0.5 s, a DC fault is applied on the line. The fault current ( trace 3) increases to 5 kA and the Id current increases to to 2 pu (4 kA) in 1

52、0 ms. Then, the fast regulator action lowers the current back to its reference value of 1 pu.. </p><p>　　0.55 < t <0.57 s</p><p>　　At t = 0.55 s, the alpha angle is forced by the protecti

53、on system (not simulated) to reach 165 degrees when the Forced_alpha input of the current regulator goes high (1). The rectifier thus passes in inverter mode and sends the energy stored in the line back to the 345 kV net

54、work. As a result, the arc current producing the fault rapidly decreases . The fault is cleared at t = 0.555 s when the fault current zero crossing is reached.</p><p>　　0.57 < t < 0.8 s</p><

55、p>　　At t = 0.57 s, the regulator is released and it starts to regulate the DC current again. The steady-state 1 pu current is reached at t = 0.75 s. </p><p>　　Frequency analysis of AC and DC voltages and

56、currents</p><p>　　In order to alllow further signal processing, signals displayed on Scope2 have been saved in a variable named 'psbvdc_str' ( structure with time'). These signals are : AC voltag

57、es (input 1) , AC currents (input 2) and DC voltages on rectifier and line side of the smoothing reactor (input 3). Open the Powergui and select 'FFT Analysis'. In the FFT window select structure 'psbhvdc_st

58、r'. The 0 - 2000 Hz FFT will be performed on a 2-cycle window starting</p><p>　　at t = 0.8 - 2/60 (last 2 cycles of recording). Select input labeled 'Iabc' . By default Phase a current (signal

59、number 1) is selected. Press on 'Display' and observethe frequency spectrum of AC current. Harmonic currents (order 6n+/-1 , n = 1,2,3, ...for a 6-pulse converter) are displayed in % of the fundamental component

60、.If you analyze AC voltage (input Vabc) you shoud notice that the highest harmonics generated by the converter (5th and 7th) are filtered out by the two filters tuned atthe 5</p><p>　　This example of AC-DC-A

61、C converter illustrates use of Universal Bridge, Multimeter and Powergui blocks as well as discrete control blocks of the Extras library</p><p>　　Circuit Description</p><p>　　A 60 Hz, voltage

62、 source feeds a 50 Hz, 50 kW load through an AC-DC-AC converter. </p><p>　　The 600V, 60 Hz voltage obtained at secondary of the Wye/Delta transformer is first rectified by a six pulse diode bridge.</p&g

63、t;<p>　　The filtered DC voltage is applied to an IGBT two-level inverter generating 50 Hz.</p><p>　　The IGBT inverter uses Pulse Width Modulation (PWM) at a 2 kHz carrier frequency.</p><p&g

64、t;　　The circuit is discretized at a sample time of 2 us.</p><p>　　The load voltage is regulated at 1 pu (380 V rms) by a PI voltage regulator using abc_to_dq and dq_to_abc transfomations. </p><p&

65、gt;　　The first output of the voltage regulator is a vector containing the three modulating signals used by the PMW Generatorto generate the 6 IGBT pulses. The second output returns the modulation index. </p><p

66、>　　The Discrete 3-Phase PWM Pulse Generator is available in the Extras/Discrete Control Blocks library. </p><p>　　The voltage regulator has been built from blocks of the Extras/Measurements and Extras/

67、Discrete Control librariesThe Multimeter block is used to observe diode and IGBT currents.</p><p>　　In order to allow further signal processing, signals displayed on Scope1 block (sampled at simulation sa

68、mpling rate of 2us )are stored in a variable named 'psbbridges_str' (structure with time) .</p><p>　　Demonstration</p><p>　　Start the simulation. After a transient period of approximate

69、ly 50 ms, the system reaches a steady state.</p><p>　　Observe voltage waveforms at DC bus, inverter output and load on Scope1.</p><p>　　The harmonics generated by the inverter around around m

70、ultiples of 2 kHz are filtered by the LC filter.</p><p>　　As expected the peak value of the load voltage is 537 V (380 Vrms). </p><p>　　In steady state the mean value of the modulation index is

71、 m = 0.80 and the mean value of the DC voltage is 778 V. </p><p>　　The fundamental component of 50 Hz voltage burried in the chopped inverter voltage is therefore:</p><p>　　Vab = 778 V * 0.612

72、* 0.80 = 381 V rmsOnce simulation is completed, open the Powergui and select 'FFT Analysis' to display the 0 - 7000 Hz frequency spectrum of signals saved in the 'psbbridges_str' structure. The FFT will

73、 be performed on a 2-cycle window starting at t=0.1-2/50 (last 2 cycles of recording). </p><p>　　Select input labeled 'Vab Load' . Click on Display and observe the frequency spectrum of last 2 cycle

74、s.</p><p>　　Notice harmonics around multiples of the 2 kHz carrier frequency. Maximum harmonic is 1.4 % of fundamental and THD is 2%. Observe diode currents on trace 1 of Scope2, showing commutation from dio

75、de 1 to diode 3. Also observe on trace 2 currents in switches 1 and 2 of the IGBT/Diode bridge (upper and lower switches connected to phase A). These two currents are complementary.</p><p>　　A positive curr

76、ent indicates a current flowing in the IGBT, whereas a negative current indicates a current flowing in the antiparallel diode.</p><p><b>　　中文翻譯</b></p><p>　　Simulink仿真演示</p>&

77、lt;p>　　Simulink是為建模工具，分析模擬物理和數(shù)學(xué)系統(tǒng)，包括那些非線性元件和那些連續(xù)和離散時(shí)間</p><p>　　作為MATLAB的延伸，Simulink的系統(tǒng)增加了許多具體的動(dòng)態(tài)特性，同時(shí)保留的MATLAB通用的所有功能。</p><p>　　在下列可以看到各類仿真運(yùn)行演示。</p><p>　　其他Simulink產(chǎn)品 </p>

78、<p>　　其他已安裝產(chǎn)品Simulink的運(yùn)行演習(xí)。試試這些演示，看看哪個(gè)Simulink的產(chǎn)品可能合適你的工作。請(qǐng)注意，這是一個(gè)Simulink產(chǎn)品的清單。你特定安裝MathWorks產(chǎn)品將可能只包括其中的一些產(chǎn)品。</p><p>　　參見(jiàn)在內(nèi)容窗格中，每個(gè)Simulink產(chǎn)品，見(jiàn)文件的例子，以查看更多的示例代碼可以運(yùn)行或復(fù)制。</p><p>　　三相三電平PWM電壓

79、源逆變器</p><p>　　這個(gè)示例展示了三相三電平逆變器和離散型三相PWM控制的發(fā)電機(jī)的仿真。它同樣展示了如何利用Powergui/FFT工具來(lái)對(duì)PWM信號(hào)波形進(jìn)行諧波分析。</p><p><b>　　電路說(shuō)明</b></p><p>　　這個(gè)系統(tǒng)由連接到雙聯(lián)的兩個(gè)三相三電平PWM電壓源型轉(zhuǎn)換器組成。這個(gè)逆變器通過(guò)三相變壓器為負(fù)載提供(1

80、kw,500var60hz)交流電.變壓器8%的漏電感和500var負(fù)載電容共同產(chǎn)生濾波作用。每一個(gè)逆變器使用特定的電力電子器件-IGBT/Diode的組合件構(gòu)成的橋式三電平模塊。每個(gè)橋臂由四個(gè)IGBT，四個(gè)反并聯(lián)二極管和兩個(gè)中點(diǎn)箝位二極管構(gòu)成。這種逆變器是在開(kāi)環(huán)回路中受控制的。脈沖由三相離散的PWM發(fā)電機(jī)模塊產(chǎn)生。這一模塊可在額外的/離散型控制模塊庫(kù)里找到。這種PWM發(fā)電機(jī)或調(diào)制器可用一個(gè)或兩個(gè)橋來(lái)產(chǎn)生三相，二電平，或者三電平逆變器所

81、需的脈沖。在這一示例中，PWM調(diào)制器在P1和P2輸出端產(chǎn)生兩組12個(gè)脈沖列（每個(gè)逆變器產(chǎn)生1組）。打開(kāi)“離散型三相PWM發(fā)電機(jī)”菜單，會(huì)發(fā)現(xiàn)這種電機(jī)可用于同步或異步的模式中。當(dāng)在同步模式中操作時(shí)，三角載波信號(hào)同步于連接到‘wt’輸出端的PLL參考角。在異步工作模式下，載波頻率是由開(kāi)關(guān)比率決定的輸出頻率的倍數(shù)。三正弦（0.85PU）調(diào)制信號(hào)由離散的三相可編程源提供來(lái)獲得0.85倍的調(diào)制指標(biāo)。載波信號(hào)同步于調(diào)制信號(hào).在PWM發(fā)電機(jī)模塊中,你

82、可以替換選擇異步的和</p><p>　　舉個(gè)例子說(shuō):母線直流電壓是400V,斬波頻率是1080HZ, 三個(gè)調(diào)制信號(hào)的magnitude是0.85并且三個(gè)發(fā)生器信號(hào)的頻率是60HZ. 為了進(jìn)一步信號(hào)處理、信號(hào)顯示在示波器中并被存儲(chǔ)在一個(gè)變量命名為“psb3phPWM3level_str”中。</p><p><b>　　演示</b></p><p&

83、gt;　　運(yùn)行仿真和觀察示波器里以下三個(gè)波形:逆變器1產(chǎn)生的Phase-neutral電壓Van_inv1,twin inverter產(chǎn)生的A相電壓Vaa,還有相與相間的負(fù)載電壓Vab. Van_inv1波形清楚地顯示了三個(gè)電平:+ 200伏,0伏,和-200伏。當(dāng)仿真結(jié)束后,打開(kāi)Powergui模塊,選擇FFT 分析,顯示出保存在psb3phPWM3level_str結(jié)構(gòu)中0-5000HZ的信號(hào)頻譜。這個(gè)FFT將在t = 0.1 -

84、2/60在一個(gè)窗口中開(kāi)始演示2循環(huán)(最后2周期的記錄)，選擇標(biāo)為Vaa 逆變器的輸出端，點(diǎn)擊顯示并且觀察最后2個(gè)周期的頻譜。Vaa逆變器的基本成分以及0-5000HZ范圍內(nèi)的總諧波失真都可以從這個(gè)頻譜圖中看到。由于在IGBTs和二極管中導(dǎo)通電壓引起的下降，逆變器的基波電壓幅值（335V）會(huì)略低于理論計(jì)算值（340V）。如一個(gè)雙逆變器，一次諧波發(fā)生頻率大約是載波頻率的雙數(shù)倍。同樣的電路用在雙配置的三相PWM逆變器中一樣能得到二電平。運(yùn)行示

85、例并在同樣條件下比較二電平和三電平逆變器的電壓，他們?cè)谙嗤念l率下產(chǎn)生諧波，但三電平的要比二電平的兩倍還要高。</p><p>　　DC / DC和DC / AC電源轉(zhuǎn)換器的PWM（離散）</p><p>　　這個(gè)例子說(shuō)明的是使用通用電橋和離散的PWM脈沖觸發(fā)器,它同時(shí)也說(shuō)明了使用Powergui/FFT工具分析PWM波形的諧波分量。</p><p><b&g

86、t;　　電路描述</b></p><p>　　這個(gè)系統(tǒng)包含三個(gè)獨(dú)立的電路,它們說(shuō)明的是幾種不同的PWM DC/DC和DC/AC逆變器。</p><p>　　所有的變換器都是由Extras/Discrete控制模塊中的離散PWM觸發(fā)器控制在開(kāi)環(huán)運(yùn)行，這三個(gè)電路使用的都是相同的直流電壓(Vdc=400V),載波頻率(1080HZ)和調(diào)制指數(shù)(m=0.8)。</p>&

87、lt;p>　　從上到下,三個(gè)電路分別是：</p><p>　　DC/DC,二象限變換器(單臂雙開(kāi)關(guān))。</p><p>　　DC/AC,雙極變換器(單臂雙開(kāi)關(guān))。</p><p>　　DC/AC,單極變換器(兩臂四開(kāi)關(guān))。</p><p>　　為了進(jìn)一步的信號(hào)處理,并顯示在三個(gè)示波塊上(采樣率3240),然后反別存儲(chǔ)在三個(gè)文件夾中

88、9;psb1phPWM1_str' , 'psb1phPWM2_str' 和'psb1phPWM3_str'。</p><p><b>　　說(shuō)明</b></p><p>　　運(yùn)行模擬程序并在示波塊中顯示除以下兩個(gè)波形：</p><p>　　負(fù)載電流波形和由PWM逆變器產(chǎn)生的電壓波形。當(dāng)模擬結(jié)束后,打開(kāi)Po

89、wergui并用FFT工具來(lái)分析保存在'psb1phPWMx_str' structures當(dāng)中的0-5000HZ的頻率范圍.FFT工具會(huì)在窗口中運(yùn)行兩個(gè)周期,從時(shí)間t=0.1到2/60.每個(gè)電路的輸入標(biāo)記為’V逆變器’，單擊顯示并獲得持續(xù)兩個(gè)周期的頻率范圍?！甐逆變器’的基波分量顯示在示波窗的最上方。用逆變器的基波分量和DC分量的幅值與給定電路的理論值比較，同時(shí)比較兩開(kāi)關(guān)和四開(kāi)關(guān)DC/AC逆變器的電壓諧波分量。對(duì)于兩開(kāi)

90、關(guān)的逆變器,一次諧波出現(xiàn)在載波頻率附近,比四開(kāi)關(guān)的逆變器諧波小,四開(kāi)關(guān)的是載波頻率的兩倍。</p><p>　　最后,清除四開(kāi)關(guān)逆變器的電流。如果現(xiàn)在運(yùn)行FFT來(lái)分析信號(hào),你會(huì)注意到兩開(kāi)關(guān)逆變器的負(fù)載電流的THD是7.3%,而四開(kāi)關(guān)逆變器的是2%。</p><p>　　演示說(shuō)明了異步電機(jī)使用在開(kāi)環(huán)速度控制在3HP220V。</p><p><b>　　電路

91、描述</b></p><p>　　一個(gè)三相3HP，220V，1725RPM電機(jī)轉(zhuǎn)速是通過(guò)正弦脈寬調(diào)制逆變器反饋的。正弦參考波的基礎(chǔ)頻率為60HZ，三角載波的頻率設(shè)置為1980HZ。PMW逆變器的建立示完全符合標(biāo)準(zhǔn)的Simulink模塊。它的輸出是通過(guò)控制電壓源之前被應(yīng)用到異步電機(jī)座的定子繞組模塊。電機(jī)的轉(zhuǎn)子是短路的。它的定子漏感抗LIS被設(shè)置成其實(shí)際值的兩倍，以此來(lái)模擬出放在逆變器和機(jī)器之間的反應(yīng)器的

92、效果。負(fù)載轉(zhuǎn)矩應(yīng)用于機(jī)器的固定軸，設(shè)置其最小值11.9Nm ,馬達(dá)啟動(dòng)按鈕速度給定值設(shè)置為1.0pu，或1725rpm，0.9秒后達(dá)到這個(gè)速度。</p><p><b>　　示范</b></p><p>　　看模擬參數(shù)，最大啟動(dòng)時(shí)間限制在10微秒內(nèi)，對(duì)較高的開(kāi)關(guān)頻率（1980HZ的逆變器）這是必需的。觀察到盡管有一個(gè)平滑反應(yīng)堆使用，但是轉(zhuǎn)子和定子電流還是很“

93、嘈雜”。在電磁轉(zhuǎn)矩波形圖上可以觀察到噪音是由PWM逆變器產(chǎn)生的。然而，電機(jī)的慣性可以防止在電機(jī)的速度波形的出現(xiàn)產(chǎn)生這種噪聲。機(jī)械定子端的線電壓主要成分的RMS值可有傅里葉模塊提取出來(lái)，該模塊在附加測(cè)量組中可以找到.最后，觀察PWM逆變器的輸出。使用VAB型變焦放大的示波器觀察波形。</p><p>　　簡(jiǎn)單6脈沖高壓直流輸電系統(tǒng)（離散）</p><p>　　該技術(shù)顯示一個(gè)簡(jiǎn)單的500MW（

94、250KV- 2KA）高壓直流輸電系統(tǒng)的穩(wěn)態(tài)和瞬態(tài)性能。</p><p><b>　　電路描述</b></p><p>　　一個(gè)500MW（250KV- 2KA）直流linterconnexion是用來(lái)傳輸從315 KV，5000MWA交流網(wǎng)絡(luò)的功能。該網(wǎng)絡(luò)是一個(gè)通過(guò)LLR阻尼等效來(lái)模擬的（80度，阻抗角為60赫茲和第3次諧波）。該轉(zhuǎn)換變壓器和整流器，均以分別與通用變

95、壓器和通用橋塊，這個(gè)轉(zhuǎn)換器是一個(gè)6脈沖整流器。它是連接到一個(gè)300公里0.5小時(shí)分布式通過(guò)平滑反應(yīng)堆LSR的參數(shù)一致。該逆變器是通過(guò)一個(gè)簡(jiǎn)單直流電壓源系列二極管（迫使單向傳導(dǎo)）和平滑反應(yīng)器大規(guī)模集成電路模擬的。通過(guò)一組過(guò)濾器提供給轉(zhuǎn)換器是無(wú)功功率所需要的（共320 MVAR的）。打開(kāi)交流濾波器子系統(tǒng)看到濾波器拓?fù)?。斷路器允許應(yīng)用直流線路故障在整流側(cè)。該控制系統(tǒng)采用兩個(gè)主要模塊，電壓發(fā)送到同步系統(tǒng)是由第二命令帶通濾波器濾除。整個(gè)控制系統(tǒng)是

96、離散型（樣本時(shí)間= 1/360/64 = 43.4us）。整流器輸出的直流線路電流與一個(gè)參考電流比較。在零和同步單元輸出所需的α發(fā)射角之間PI調(diào)節(jié)保持錯(cuò)誤。當(dāng)輸入3和4允許電流調(diào)節(jié)繞過(guò)調(diào)節(jié)作用，去提高α發(fā)射角。</p><p><b>　　示范</b></p><p>　　請(qǐng)注意該系統(tǒng)是離散型（采樣時(shí)間1/360/64 = 43.4我們）。設(shè)置采樣時(shí)間為零，將改變?yōu)槌?/p>

97、續(xù)集成的電力系統(tǒng)。開(kāi)始啟動(dòng)運(yùn)行該系統(tǒng)達(dá)到穩(wěn)定狀態(tài)。然后，第一步是應(yīng)用基準(zhǔn)電流去觀察監(jiān)視動(dòng)態(tài)響應(yīng)。 最后一個(gè)錯(cuò)誤直流應(yīng)用于線路。</p><p>　　啟動(dòng)模擬和觀察Scope1下列活動(dòng)：</p><p><b>　　0 <t<0.3s</b></p><p>　　跟蹤1顯示了參考電流和測(cè)量Id電流（黃色）?；鶞?zhǔn)電流設(shè)置為0.5pu（1

98、 kA的）。直流電流開(kāi)始從零在0.1 s內(nèi)達(dá)到一個(gè)穩(wěn)定狀態(tài)。跟蹤2顯示了α發(fā)射角需要獲得0.5pu電流（30度）。</p><p>　　0.3 <t<0.5s</p><p>　　在t = 0.3 s時(shí)，基準(zhǔn)電流從0.5pu（1 KA）到額定電流1pu（2 KA）。電流調(diào)節(jié)反應(yīng)大約0.1秒（6個(gè)周期）。α角從30度下降到15度。</p><p>　　0.

99、5 <t<0.55 s</p><p>　　在t = 0.5 s時(shí)，直流故障應(yīng)用于線路。故障電流增加至5 KA，ID電流在10us內(nèi)增加到2pu（4 KA）。然后，快速調(diào)節(jié)作用降低電流使其回到參考值1pu。</p><p>　　0.55 <t<0.57 s</p><p>　　在t = 0.55 s時(shí)，當(dāng)α角給電流調(diào)節(jié)器輸入高電平（1）時(shí)，α

100、角是迫于保護(hù)系統(tǒng)（未模擬）達(dá)到165度。因此，通過(guò)在整流逆變器和發(fā)送模式行中存儲(chǔ)回345千伏電網(wǎng)的能量。因此，電弧電流產(chǎn)生故障迅速下降。當(dāng)故障電流過(guò)零時(shí)，該故障在t = 0.555s時(shí)被清除。</p><p>　　0.57 <t<0.8 s</p><p>　　在t = 0.57 s時(shí)，釋放調(diào)節(jié)器，再次開(kāi)始調(diào)節(jié)直流電流。在t = 0.75秒時(shí)穩(wěn)態(tài)電流達(dá)到1pu交直流電壓和電流頻

101、率分析。為了進(jìn)一步的信號(hào)處理，信號(hào)顯示在Scope2命名為'psbvdc_str一個(gè)變量?jī)?nèi)保存（與時(shí)間結(jié)構(gòu)）。這些信號(hào)是：交流電壓（輸入1），交流電流（輸入2），整流器和平滑線的反應(yīng)器（輸入3）側(cè)直流電壓。</p><p>　　打開(kāi)Powergui并選擇FFT分析。在FFT的窗口中選擇psbhvdc_str。在2周期開(kāi)始窗口開(kāi)始執(zhí)行0 - 2000赫茲的FFT。在t = 0.8 - 2 / 60（最后2周

102、期完成），選擇輸入標(biāo)記'Iabc'，在默認(rèn)情況下A相電流（信號(hào)數(shù)字1）被選中。按下顯示和觀察頻譜的交流電流。諧波電流都顯示基本組成部分％。如果你分析交流電壓（輸入Vabc）你將要注意，轉(zhuǎn)換過(guò)濾器把產(chǎn)生的高次諧波過(guò)濾。最后，選擇輸入標(biāo)簽為Vd Vdl(pu)，然后輸入1或輸入2。您將獲得諧波含量直流分量。</p><p>　　交流-直流-交流PWM逆變器</p><p>　

103、　這個(gè)交-直交的例子說(shuō)明了對(duì)萬(wàn)用電橋，萬(wàn)用表，還有Powergui模塊的使用，如在Extras庫(kù)里的離散控制模塊。</p><p><b>　　電路說(shuō)明</b></p><p>　　一個(gè)60HZ的電壓源通過(guò)交直交逆變器為50HZ，50KW的負(fù)載提供電源。</p><p>　　600V，60HZ的電壓被從星/三角型變壓器的二次側(cè)，被一個(gè)6脈沖二極

104、管整流橋整流獲得。</p><p>　　濾過(guò)的直流電壓被用在IGBT控制的二電平逆變器中產(chǎn)生50HZ的電源。此IGBT逆變器用PWM控制，它的載波頻率是2 kHz。該電路在取樣周期內(nèi)是離散的。負(fù)載電壓通過(guò)PI電壓調(diào)節(jié)器以1個(gè)功率單位進(jìn)行調(diào)節(jié)，變換方式是abc軸到dq 軸和 dq軸到abc軸。電壓調(diào)節(jié)器的一次輸出是包括三個(gè)調(diào)制信號(hào)的矢量，用在PWM發(fā)電機(jī)來(lái)產(chǎn)生這6個(gè)IGBT的脈沖波，二次輸出返回到調(diào)節(jié)器首端。離散型