[雙語翻譯]外文翻譯--c型無源濾波器的一種新型設計方法（英文）

1、PRZEGL?D ELEKTROTECHNICZNY (Electrical Review), ISSN 0033-2097, R. 88 NR 7a/2012 277 Ryszard KLEMPKA Akademia Górniczo-Hutnicza, Wydzia? Elektrotechniki, Automatyki, In

2、formatyki i Elektroniki A New Method for the C-Type Passive Filter Design Abstract. The paper presents the new C-type high harmonic power filter design process whose aim is the reduction of total harmonic distortion in a

3、n industrial power supply system. A new method for C-type filter design is proposed and an example of the method application to an industrial plant is provided. The basis for the new algorithm is assuming, at the desig

4、n phase, the required distribution of the harmonic current between the filter to be tuned to that harmonic and the supply network. This method takes into consideration the network equivalent impedance. Streszczenie. Ni

5、niejszy artyku? przedstawia projektowanie energetycznego filtru typu C wy?szych harmonicznych, którego zadaniem jest zmniejszenie wspó?czynnika zawarto?ci harmonicznych w przemys?owym systemie zasilania. Zapro

6、ponowano now? metod? projektowania C-filtru oraz przedstawiono przyk?ad zastosowania tej metody projektowania w praktyce dla zak?adu przemys?owego. (Nowa metoda projektowania filtru typu C). Keywords: passive filter, c

7、ompensation, power system harmonics, C-type filter. S?owa kluczowe: filtry pasywne, kompensacja mocy biernej, harmoniczne, filtr typu C. Introduction An ever-increasing number of large-power nonlinear loads, installed

8、 in industry is the reason that passive harmonic filters are still the most common way to reduce voltage distortion at their points of connection. Many passive LC filter systems, of various structures and different o

9、perating characteristics have been developed [1] – [4]. Nevertheless, the single-tuned single branch filter still is the dominant solution for industrial applications, and it certainly is the basis for understanding m

10、ore advanced filtering structures, such as the C-type filter. An alternative solution can be active filters or hybrid filters that combine these structures [5] – [7]. Both the design and control of such systems can

11、be a task employing artificial intelligence methods, e.g. neural networks or genetic algorithms [8] – [10]. The principal disadvantage of the majority of currently used filter-compensating device structures is poor f

12、iltering of high frequencies. In order to eliminate these disadvantages are usually used broadband (damped) filters of the first, second or third order; the C-type filter is included in the category of broadba

13、nd filters. Broadband filters have additional advantage, substantial for their co-operation with power electronic converters: they damp commutation notches more effectively than single branch filters - they have a mu

14、ch broader bandwidth. They also more effectively eliminate interharmonic components (in sidebands adjacent to characteristic harmonics) generated by static frequency converters. That filter, as compared to single br

15、anch filters, also ensures reduction of active power losses because the 2 2C Lbranch (Fig. 1) is tuned to the fundamental harmonic frequency. The fundamental harmonic current is not passing through the resistor RT, avo

16、iding therefore large power losses. The method for determining C-type filter parameters is described in [11]. Complex passive filters are more and more often designed using artificial intelligence methods, like gen

17、etic algorithms [12] – [13] that can also be effective in solving other problems [14] – [20]. Determination of the C-Type Filter Parameters The paper describes a new method for determining the C- type filter parameter

18、s. Designing of filters for large power systems is a complex task: aside of determining the filter parameters to meet the design requirements, the filter shall be checked for possible resonance occurrences due to int

19、eraction with other passive components in the power system [21] – [22]. The filter parameters can be determined from relations given in [11]. This paper proposes a new, and simpler, method for determining the filter

20、parameters. The method consists in assuming, at the design phase, the desired distribution of the harmonic current between the filter tuned to that harmonic and the supply network. This method requires taking into co

21、nsideration the network equivalent impedance. The C-type filter diagram is shown in Fig. 1. Fig. 1. The C-type filter circuit The filter impedance is given by: (1) 12222 1 11C jC j L j RR C j L jZTTF ? ? ?? ?? ? ?? ?

22、?? ? ? ?? ??The L2 and C2 components are tuned to the fundamental frequency (2) 2 2 12 1C L ? ?Hence (3) ? ? ? ? 1 2 1 2 2 2 12 1 2 1C j j C RjR ZTT F ? ? ? ??? ? ? ? ?? ?The C-type filter is tuned to the resonance a

23、ngular frequency 1 ? ? r r n ?(4) ? ? 1 1 2 1 22 12 1 2? ? ??? r r n C CC CC C L?hence RTL2 C2 C1 UIF IS ILoad Load PRZEGL?D ELEKTROTECHNICZNY (Electrical Review), ISSN 0033-2097, R. 88 NR 7a/2012

24、 279 Fig. 3. Frequency-impedance characteristics of: a) the power network equivalent impedance (ZS), the resultant impedance of two 3rd harmonic filters (Z2x3h), the C-type filter impedance (Z

25、Cfilter), the resultant impedance of two 3rd harmonic filters and the C-type filter (ZF); b) the impedance seen from the load terminals: without filters (ZS), the network equivalent impedance and two 3rd harmonic fil

26、ters impedance connected in parallel (Zs||Z2x3h), and parallel connection of the network equivalent impedance, two 3rd harmonic filters and the C-type filter impedances (Zs||Z2x3h||ZCfilter). Figure 4a shows the C-t

27、ype filter frequency characteristics for different quality factors, figure 4b illustrates the relation between the resistance RT and the coefficient k that indicates the distribution of the current harmonic to whic

28、h the filter is tuned. Table 3. The percentage distribution of the harmonic current between the filter tuned to that harmonic and the supply network; the corresponding RT values and the designed filter quality factor

29、 IF [%] IS [%] k RT [?] 38.5 61.5 1.60 172 44.4 55.6 1.25 221 50.0 50.0 1.00 276.86 51.9 48.1 0.93 300 57.1 42.9 0.75 350 66.6 33.3 0.50 555 75.0 25.0 0.33 840 83.3 16.7 0.25 1111 91.0 9.0

30、 0.10 2778 Data in table 3 shows the percentage distribution of the harmonic current between the filter tuned to that harmonic and the supply network. The values of the factor k corresponding to the RT values are als

31、o provided in the table. Fig. 4. a) The C-type filter frequency characteristics for various quality factors, b) the resistance RT vs. the coefficient k Implementation and Measurements In order to verify the effective

32、ness of the proposed method has been designed a C-type filter for an electric arc furnace power supply system (Fig, 2). The designed C-type filter was installed in the arc furnace supply system. The capacitance C1 i

33、s composed of 60 capacitors (20 per phase) with capacitance 14.15?F each, which gives total capacitance C1 = 70.75?F. The capacitance C2 is composed of 24 capacitors (8 per phase) with capacitances 24.6?F eac

34、h, which gives total capacitance C2 = 196.8?F. The reactor L2 parameters should be recalculated because of alteration of the capacitance C2 due to the installation modifications (L2 = 51.48mH). The resistor res

35、istance is RT = 300? ? 10%. The diagram of the actual single-phase filter circuit is depicted in Fig. 5. Fig. 5. Diagram of the actual C-type filter circuit 1 1.5 2 2.5 3 3.5 405101520253035404550n ZCfiltr Z2x3h Zs ZF

36、 |ZCfiltr| |Z2x3h| |Zs| |ZF| a) 1 1.5 2 2.5 3 3.5 4012345678910 n Zs Zs||Z2x3h Zs||Z2x3h||ZCfilter |Zs||Z2x3h||ZCfiltr| |Zs||Z2x3h| |Zs| b) rF XZr nn a)0 1 2 3 4 5 6 024681012R ??qF2=20qF2=10 qF2=15qF2=10 qF2=15 qF