黃昭明 Front End Sales Taiwan ABB 主動濾波器原理 November, 2007-1- -
如何解決諧波問題 從用電設備結構方面的考量 較精密設備或容易受到諧波干擾的設備應該隔離於諧波負載 使用較多脈波數之驅動器 利用特殊設計變壓器耦合 此法通常僅適和於設計階段 並非全部的非線性負載都適用 可能造成較大投資成本, 同時需要更多的安裝空間 - 2
如何解決諧波問題 被動濾波器 : 提供諧波電流低阻抗路徑 Series impedanc ce Capacitive behaviour Inductive behaviour R 濾波效能與電源系統阻抗有關 有諧波濾波器過載的問題 擴充容量不容易, 且占空間 有諧波共振的危險 多次諧波電流需要多組諧波濾波器 ( 帶通 ) 必定輸出電容性虛功 交流變頻器不需要電容性虛功 超前功因的進相電流對於發電機有不良的影響 ω 0 Frequency -3
如何解決諧波問題 串聯被動與主動裝置 ( 串聯型主動濾波器 ) 其方法是提高諧波頻率之阻抗, 使諧波電流無法流回電源 i distortion ti Supply Series device Load 該裝置與負載串聯 : 需要高品質的旁通裝置 (bypass device) 影響供電至負載端電壓 必須仔細預估負載電流的大小 (fundamental + harmonics) 擴充性較困難 可能造成較高的諧波電壓 ( current has to flow ) -4
如何解決諧波問題 使用低諧波變頻器 AC drives: Supply L1 L2 L3 Diode bridge rectifier DC link L + C - U d Inverter V1 V3 V5 V4 V6 V2 U1 V1 W1 Supply L1 L2 L3 Input filter L or LCL IGBT bid bridge L + C - U d Inverter V1 V3 V5 V4 V6 V2 U1 V1 W1-5
使用低諧波變頻器應用範圍 使用低諧波變頻器可以控制 AC motors Motor M3 低諧波變頻器無法應用於交流馬達以外的負載, 例如 三相四線式供電的辦公室有大量三次諧波 ( PQFK -application area) 直流馬達的控制 其他 - 6
低壓電網電力品質改善 - 使用並聯型主動濾波器 Active filters: Supply Load Harmonics injection - 7
低壓電網電力品質改善 - 使用並聯型主動濾波器 ABB premium class Active Filters: - 8 PQFS PQFK PQFM PQFI Leading by excellence!
主動濾波器原理 並聯運作方式 : 基本觀念 主動濾波器與負載並聯, 對匯流排注入諧波電流 i distortion Supply Load Coupling system i compensation Active Filter -9
1. 3-1.3 0 36 0 1. 3-1.3 0 360 1. 3-1.3 0 360 主動濾波器原理 當今主動濾波器技術 : 選擇性濾波, 使用上更具彈性 可以濾波至較高次如 47,49 次諧波 補償功率因數 FUNDAMENTAL ONLY 負載不平衡補償 Feeder 輸出限制不過載 可以輕易擴充容量 電網資訊監控 其他 PQF ONLY HARMONICS -10
40 20 0-20 1. 3-1.3 0 360 1 5 7 11 13 17 19 40 20 0-20 1. 3-1.3 0 360 1 5 7 11 13 17 19 40 20 0-20 1. 3 0 360 1 5 7 11 13 17 19 主動濾波器原理 ABB Active harmonic filters(saf) 濾波原理 : 主動濾波器注入諧波電流, 其大小相等但是相角相反以抵消負載諧波電流 Wavefor rms CLEAN FEEDER CURRENT LOAD CURRENT -1.3 ACTIVE FILTER CURRENT Ha armonics = + -11
主動濾波器如何運作 (1) Output filter Line reactor PWM reactor -12 Control system PWM Inverter ete (IGBT-based)
主動濾波器如何運作 (2) Physical Signals Measurements State of the art digital DSP system Power inverter control signals -13 High filtering efficiency and reliability Modern digital technology using multi-dsp systems and MicroController
主動濾波器的運作模式 Highest PRIORITY Lowest -14 Mode 1 Filtering to curve Maximum filtering Reactive compensation Mode 2 Filtering to curve Reactive compensation Maximum filtering Mode 3 Filtering to curve Reactive compensation 虛功補償方式 : - 無 - 動態 (cosφ target) - 靜態 (constant Q) - 平衡負載
控制模式變換策略 Max. Filtering & Q Compensation Maximum Filtering Load increase Filtering to Curve Load Filtering to decrease Hardware Limits - 15
濾波器性能範圍 Technical requirements Filter upto H13 ABB Filter upto H50 Filter upto H25 符合諧波管制規範 -16
主動濾波器的控制迴路 最佳的性能尤其是高次諧波必須使用閉迴路控制系統 直接量測流回電源的諧波電流 修正系統不確定性 closed loop Distortion ti 能夠直接比對各次諧波管制標準 source 可以改善功率因數 簡單的 CT 接線 容易擴充特性 可以在主迴路或分路安裝主動濾波器 Active filter open loop Distortion source Active filter -17
40 20 0-20 1 5 7 11 13 17 19 40 20 0-20 1 5 7 11 13 17 19 40 20 0-20 1 5 7 11 13 17 19 主動濾波器的控制方法 諧波性能使用頻率領域分析法提供可靠的控制系統 CLEAN FEEDER CURRENT LOAD CURRENT ACTIVE FILTER CURRENT = + 各次諧波 ( 含高次諧波 ) 控制尤其獨立的最佳化控制模型 各自獨立的諧波濾波選擇功能可以充分使用濾波器資源 配合閉迴路控制演算法, 允許使用者對各次諧波作設定 -18
為何使用閉迴路控制? 直接測量與控制流回電源系統諧波電流 不使用計算值 THDI 不會出現錯誤的風險 直接比對諧波電流是否符合管制標準 簡單的 CT 接線 一般型式 CT X/5A class 1 就足夠 容易擴充容量 較佳的控制精確度與安全性 部分負載補償或全負載補償都適用 Closed loop control PQF VFD Open loop operation Control point Other loads Control point CT : x/5a Directly control & measure THDI and total load current then compensate VFD VFD VFD VFD spare Future extent ion = easy THDI =? unknown Total loads =? Unknown Pass/fail regulation =? Unknown CT:x/1A CT CT CT CT AF? VFD VFD VFD VFD VFD spare Other loads SCT Accuracy drop! Future extent ion =? -19
可控電壓源 : DC Bus 幾乎沒有能量損失, 能量只有 DC/AC 之間的轉換 經由輸出電抗器轉換成為諧波電流 基本波虛功率輸出作為功因補償或是負載平衡 直流電容器 (DC capacitors) 儲存電能 (Store energy) 降低電壓變動 (Reduce voltage fluctuations) PQFI and M : 使用乾式直流電容器 (DRY FILM technology) => High current rating, environmental friendly, increased lifetime PQFK : 使用電解電容器 -20
可控電壓源 : DC Bus 安全性 (Safety): => 平衡電壓 + 低速放電電阻 => 主動放電系統 `Active Discharge System (ADS) 主動濾波器損失 Inverter losses (switching, conduction) Output filter resistors and reactors losses Discharge resistor losses -21 Inverter has to be able to inject currents on the network Self powered inverter : UDC > UNetPeak
可控電壓源 : 脈波寬度調變 Pulse Width Modulation U S+ If S+ is more often closed than S- 0<Uout<U R L Iout S- If S- is more often closed than S+ -U<Uout<0-22
可控電壓源 : 脈波寬度調變 Pulse Width Modulation Modulation frequency must be higher than useful frequency (Nyquist theorem) Filter harmonics up to 2500Hz PWM frequency higher than 5000Hz => PWM switching is synchronised with the network frequency - 23
可控電壓源 : IGBT Switches Switching device Controlled switching Harmonics up to 2500Hz UDC in the 1KV range Voltage controlled Insulated Gate Bipolar Transistor / Free Wheel Diode - 24
可控電壓源 : Implementation IGBTs and FWDs + DC capacitors Low inductance bus bar Snubber capacitors - Balancing (discharge) resistors SKiiP solution (SemiKron Integrated Intelligent Power) -25
可控電壓源 : Implementation High performance semiconductors IGBTs Fast FWDs Internal IGBT driver Full galvanic insulation Error signals (OC, OT) Feedback of current information from all phases Reliability Easy to use Feedback of temperature information from all phases -26 Optical communication link between the main control unit and the power units for increased reliability
Voltage to Current Conversion PWM Reactors Controlled Voltage Source Controlled Current Source - 27
RMS current limitation I n = U AF n ω L + ACTIVE - FILTER - 28
RMS current limitation 250 A RMS fundamental Filtering capability 250 A RMS H2, H3, H4, H5 240 200 160 250*5/n 5/n A RMS Hn 120 Any combination with 40 Harmonics maximum 250 A RMS 0 0 5 10 15 20 25 80-29
RMS current limitation 250 225 250 250 200 150 200 150 135 180 200 150 150 125 100 50 100 50 100 50 50 80 60 0 0 1 5 7 11 13 1 5 7 11 13 1 5 7 11 13 0 I RMS = I H 2 I H_RMS -30
Peak voltage limitation No H 5 30% H 5 (0 ) 30% H 5 (180 ) 150% 100% 50% 0% -50% -100% -150% 150% 100% 50% 0% -50% -100% -150% 150% 100% 50% 0% -50% -100% -150% Peak 100% Peak 130% Peak 112% -31
CT 安裝位置 PQF LOAD LOAD LOAD ALWAYS CLOSED LOOP -32 PQF LOAD
CTs - Special arrangements (1) Physical installation possible only on side B Global compensation wanted (side A& side B) No access to transformer busbars LOADS LOADS (Side A) (Side B) PQF CTs connection? -33
CTs - Special arrangements (1) Summator CT x-x/5 Real CT ratio = 2x/5 LOADS LOADS (Side A) (Side B) PQF -34
CT - Summator connection Times 3 phases! S1 P1 S2 P2 S1 K S1 P3 S2 L S2 P4 PQF -35 Side A Side B P1 = PA1 P2 = PA2 P3 = PB1 P4 = PB2
CTs - Special arrangements (2) No access to transformer busbars Only load feeder can be accessed LOAD PQF CTs connection? - 36
CTs - Special arrangements (2) S1 S2 S1 P1 P2 P3 S1 S2 LOAD S2 l k PQF P4-37
CTs - Special arrangements (3) Tie normally open (independent transfos) PQF Must filter even in degraded mode (tie closed, only one transfo connected) PQF - 38
CTs - Special arrangements (3) S1 S2 I1 I0 I2 S1 S2 S1S2S P3P4 P1 P2 P1P2 P3 P4 S1S2 I 1-I 0 S1S2 I 2+I 0 PQF 1 PQF 2-39
主動濾波器與電容器 CT location & capacitor units 如果 CT 可以測量電容器電流時 如果電容器並未串聯任何電抗器 則主動濾波器在共振頻率會變成不穩定 如果是非調諧電容器 (Detuned Capcitor) 則主動濾波器可能會過載, 如果諧波歧變過大 建議使用加法比流器 (Summing CTs), 讓 CT 不要測量到電容器電流 - 40
應用例 : Variable speed drives in oil field LINE VOLTAGES & LINE CURRENTS AT PUMPING CLUSTER 750 500 250 Volts 0-250 -500-750 3000 2000 1000 Am mps 0-1000 -2000-3000 10:25:43.72 10:25:43.73 10:25:43.74 10:25:43.75 10:25:43.76 10:25:43.77 CHA Volts CHB Volts CHC Volts CHA Amps CHB Amps CHC Amps -41 Waveform event at 22/11/01 10:25:43.533 Voltage: THDV = 12% Current: THDI = 27%
應用例 : Variable speed drives in oil field LINE VOLTAGES & LINE CURRENT WITH ACTIVE FILTER 750 500 250 0 250 500 750 000 000 000 0 000 000 000 10:41:55.72 10:41:55.73 10:41:55.74 10:41:55.75 10:41:55.76 10:41:55.77 10:41:55.7 CHA Volts CHB Volts CHC Volts CHA Amps CHB Amps CHC Amps Voltage: THDV = 2% Waveform event at 22/11/01 10:41:55.533 Current: THDI = 3% -42
應用例 : 三相四線式平衡負載功能 (Load Balancing) L1: 49.1 Arms L2: 5.3 Arms L3: 5.1 Arms N: 44.1 Arms L1: 19.6 Arms L2: 19.4 Arms N: 3.5 Arms -43 L3: 19.5 Arms
1200 1000 800 600 400 200 0-200 -400-600 -800-1000 -1200 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 應用例 : 不平衡負載 Unbalanced load filtering Lo oad sid [200 L3 de curr 0A/div] L2 rents ] L1 Time [5ms/div] -44
1200 1000 800 600 400 200 0-200 -400-600 -800-1000 -1200 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 應用例 : 不平衡負載 Unbalanced load filtering Sup pply si [200 L3 ide cur 0A/div] L2 rrents ] L1 Time [5ms/div] -45
TWABB Top 3 Priority In Taiwan, we Take Lead in Safety Take Pride in Ethics Take Heart in Quality 為工安帶頭以操守為榮對品質用心 - 46
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