CN103904663B - A kind of active power quality comprehensive regulating device and detection algorithm thereof - Google Patents

Abstract

The present invention relates to a kind of active power quality comprehensive regulating device and detection algorithm thereof, comprise cabinet, power cell, protective plate, breaker unit, secondary installing Slab element, DC capacitor unit, blower fan, L1 reactor, L2 reactor, filter capacitor, contactor, secondary installing Slab element supports fixing by secondary installing plate, secondary installing plate is made by sheet metal; Cabinet top is provided with louver(-vre), and bottom is provided with ventilating blind, and cabinet upper rear portion and bottom are equipped with inlet wire jockey.Advantage is: same device, under Systematical control, SVG(static reacance generator can be realized respectively) or APF(Active Power Filter-APF) function, also can realize SVG and APF function, namely the design takes into account the functional requirement of SVG or APF simultaneously from hardware and software simultaneously.This device is easy to realize dilatation respectively; Adopt modularized design, power density is high, and volume is little, reduces and connects busbar length.

Description

A kind of active power quality comprehensive regulating device and detection algorithm thereof

Technical field

The invention belongs to power quality controlling equipment field, particularly relate to a kind of active power quality comprehensive regulating device and detection algorithm thereof.

Background technology

Along with the raising of national economy strength and the development fast of power industry, large power power electronic appliance is progressively widely used in the industry, and the idle and harmonic pollution therefore produced is also day by day serious.

Nowadays the high-power switch device of various power electronic equipment all works under nonlinear state, this not only makes the power factor of network system reduce to a certain extent, and a large amount of harmonic currents is also injected in electrical network, form huge Electric Power Disserve, cause the unsteadiness of electrical network, dangerous and waste, for this reason, idle and harmonic wave control has important practical significance.

Tradition reactive power compensation and harmonic decrease devices and technology, can reach the object of reactive power compensation and harmonic wave control, but existing defects, can be summarized as:

(1) treat some special idle harmonious wave energy enough simply to administer;

(2) existing technology, can not process idle and harmonic wave in the same apparatus simultaneously;

(3) design of legacy equipment structure is loose, and volume is large, and power consumption own is large, and non-ferrous metal consumptive material is also more, adds production cost.

(4) apparatus control system is easily subject to electromagnetic interference, affects the steady operation of equipment.

(5) equipment is easily subject to the impact of ambient temperature, humidity, salt fog and electrostatic, causes the fault such as apparatus overheat, partial discharge.

(6) device structure design is complicated, and production efficiency is low, and maintain and replace is inconvenient.

(7) filter effect that is linear or nonlinear load frequently changed to harmonic number is not fine;

Sui the development of modern power electronics technology, and people adopt Active Power Filter-APF to substitute passive filter.

Active Power Filter-APF divides and is used alone the large class with used in combination two, and during General Requirements, be used alone and can meet the demands, it is used alone, and divides again parallel connection type and tandem type.At present, because load access electrical network walks abreast, so claim this mode to be parallel connection type with main circuit.This form is that Active Power Filter-APF is the most a kind of, is also the one that current range of application is the widest.But the cabinet body structure of existing parallel connection type active electric filter is huge, oneself power consumption is large, and harmonic filtration scope is little, and response speed is slow, and can not administer multiple power quality problem, without automatic current limiting operation function, degree of intelligence is low, only has the shortcomings such as simulative display simultaneously.

Summary of the invention

For overcoming the deficiencies in the prior art, the object of this invention is to provide a kind of active power quality comprehensive regulating device and detection algorithm thereof, realizing idle and harmonic wave control simultaneously, overall structure reduces volume.

For achieving the above object, the present invention is achieved through the following technical solutions:

A kind of active power quality comprehensive regulating device and detection algorithm thereof, comprise cabinet, power cell, protective plate, breaker unit, secondary installing Slab element, DC capacitor unit, blower fan, L1 reactor, L2 reactor, filter capacitor, contactor,

Secondary installing Slab element supports fixing by secondary installing plate, secondary installing plate is made by sheet metal;

Cabinet top is provided with louver(-vre), and bottom is provided with ventilating blind, and the front of cabinet outside is provided with cabinet door, and cabinet upper rear portion and bottom are equipped with inlet wire jockey;

Be divided into four-layer structure in cabinet, ground floor is provided with power cell, DC capacitor unit, blower fan, and wherein, power cell and DC capacitor unit are split-type structural, and power cell is placed in cabinet front near cabinet door place, and DC capacitor bottom is provided with blower fan; The second layer is provided with L2 reactor and secondary installing Slab element, and secondary installing Slab element is arranged on power cell bottom; Third layer is provided with L1 reactor, filter capacitor; Bottom is provided with contactor and breaker unit, and be provided with protective plate in described cabinet front cabinet door, power cell outside is provided with protective cover; Described protective plate and protective cover all adopt degradable nonmetallic materials to make.

The circuit board of described secondary installing Slab element is coated with three anti-enamelled coatings.

Described DC capacitor unit outside is provided with fin.

Described power cell comprises IGBT module, drives keyset, radiator, and wherein, IGBT module is connected with driving keyset, and IGBT module is by radiator heat-dissipation, and described radiator is made up of the heating panel of several dentalations.

The detection algorithm that the quality of power supply utilizing said apparatus to realize regulates, comprises the following steps:

1) instantaneous value of three-phase voltage and electric current is established to be respectively e _a, e _b, e _cand i _a, i _b, i _c, they are carried out the conversion of abc/ alpha-beta, under being transformed into the orthogonal rest frame of alpha-beta two-phase, two-phase instantaneous voltage e can be obtained _α, e _βwith two-phase transient current i _α, i _β:

$\left[\begin{array}{c}{e}_{\mathrm{\α}}\\ e_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{e}_a\\ e_b\\ e_c\end{array}\right]---\left(1\right)$

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{i}_a\\ i_b\\ i_c\end{array}\right]---\left(2\right)$

In formula (1), (2) $C_{2/3}=\sqrt{2/3}\left[\begin{array}{ccc}1& -1/2& -1/2\\ 0& \sqrt{3}/2& -\sqrt{3}/2\end{array}\right];$

2) formula (3) is defined to obtain according to active power p and reactive power q

$\left[\begin{array}{c}p\\ q\end{array}\right]=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right]=C_{\mathrm{pq}}\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]---\left(3\right)$

In formula (3) $C_{\mathrm{pq}}=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right];$

3) active power p, reactive power q obtain formula (4) through low pass filter LPF

Wherein for instantaneous active power, for instantaneous reactive power, 3E is three-phase instantaneous voltage, I ₁for transient current, for phase angle;

4) by sensed current i can be calculated _a, i _b, i _cin fundametal compoment i _af, i _bf, i _cf

$\left[\begin{array}{c}{i}_{\mathrm{af}}\\ i_{\mathrm{bf}}\\ i_{\mathrm{cf}}\end{array}\right]=C_{3/2}{C}_{\mathrm{pq}}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]=\frac{1}{{3E}^2}{C}_{3/2}{C}_{\mathrm{pq}}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]---\left(5\right)$

5) by sensed current i can be calculated according to formula (6) _a, i _b, i _cin fundamental active component i _apf, i _bpf, i _cpf

$\left[\begin{array}{c}{i}_{\mathrm{apf}}\\ i_{\mathrm{bpf}}\\ i_{\mathrm{cpf}}\end{array}\right]=C_{2/3}{C}_{\mathrm{pq}}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ 0\end{array}\right]---\left(6\right)$

Then sensed current i _a, i _b, i _charmonic current and reactive current sum is with the difference of fundamental active current.

Realize independent idle control, separately harmonic controling and SVG+APF by control system to control.

Compared with prior art, the invention has the beneficial effects as follows:

1, same device, under Systematical control, can realize SVG(static reacance generator respectively) or APF(Active Power Filter-APF) function, also can realize SVG and APF function, namely the design takes into account the functional requirement of SVG or APF simultaneously from hardware and software simultaneously.The multiple power quality problems such as the harmonic wave simultaneously changed in automatic tracking and compensating electrical network, idle, negative phase-sequence.It is that 2 ~ 50 subharmonic filtering gamuts are effective that SVG range of operation reaches-100% ~+100%, APF filter range, and free function is arranged;

2, power cell and direct current capacitor unit design for split-type structural, are easy to realize dilatation respectively;

3, adopt modularized design, power density is high, and volume is little, and reduce and connect busbar length, namely non-ferrous metal consumption is little;

4, adopt mean value carrier modulation technique, equipment itself does not produce humorous wave interference;

5, adopt the protective plate of degradable nonmetallic materials, achieve the isolating and protecting of major loop and control system, be i.e. dust-proof, damp proof, Defend salt fog and antistatic.Meanwhile, the smooth and easy and security of operation of ventilation and heat is ensured;

6, major loop and control system have employed secondary installing Slab element structural design and achieve and shield worn-out the isolation, electromagnetism interference;

7, built-in blower fan, can realize malleation low noise and ventilate and high efficiency and heat radiation;

8, rack is upper and lower, is all designed with inlet wire jockey, realization can inlet wire entirely compatible.

Accompanying drawing explanation

Fig. 1 is main circuit schematic diagram of the present invention.

Fig. 2 is the outside drawing of cabinet door.

Fig. 3 is front view of the present invention.

Fig. 4 is right view of the present invention.

Fig. 5 is rearview of the present invention.

Fig. 6 is power cell structure schematic diagram.

Fig. 7 is the heat spreader structures schematic diagram of power cell.

Fig. 8 is secondary installing Slab element structural representation.

Fig. 9 is stereogram of the present invention.

Figure 10 is stereogram of the present invention (unshielded plate).

Figure 11 is air channel of the present invention schematic diagram.

Figure 12 is voltage, current phasor figure in alpha-beta coordinate system.

Figure 13 is wave superposition theory diagram.

In figure: 1-cabinet 1-1 touch screen 1-2 scram button 2-power cell 2-1IGBT module 2-2 drives keyset 2-3 radiator 3-protective plate 4-breaker unit 5-secondary installing Slab element 5-1 secondary installing plate 5-2 master control borad 5-3 direct voltage sampling plate Holl-PT5-4 three phase rectifier bridge module 5-575W Switching Power Supply 5-6 rectifier 5-7150W Switching Power Supply 5-8 relay 5-9 three-phase transformer 5-10 air switch 5-11 contactor 5-12 charging resistor 6-DC capacitor unit 7-blower fan 8-L2 reactor 9-L1 reactor 10-filter capacitor 11-main contactor 12-inlet wire jockey.

Embodiment

Below in conjunction with Figure of description, the present invention is described in detail, but it should be noted that enforcement of the present invention is not limited to following execution mode.

See Fig. 1-Figure 11, a kind of active power quality comprehensive regulating device and detection algorithm thereof, comprise cabinet 1, power cell 2, protective plate 3, breaker unit 4, secondary installing Slab element 5, DC capacitor unit 6, blower fan 7, L1 reactor 9, L2 reactor 8, filter capacitor 10, main contactor 11, secondary installing Slab element 5 supports fixing by secondary installing plate 5-1, secondary installing plate 5-1 is made by sheet metal;

Cabinet 1 top is provided with louver(-vre), and bottom is provided with ventilating blind, and the front of cabinet 1 outside is provided with cabinet door; Cabinet 1 upper rear portion and bottom are equipped with inlet wire jockey 12;

Four-layer structure is divided in cabinet 1, ground floor is provided with power cell 2, DC capacitor unit 6, blower fan 7, wherein, power cell 2 and DC capacitor unit 6 are split-type structural, power cell 2 is arranged on cabinet 1 front near cabinet door place, DC capacitor unit 6 outside is provided with fin, and DC capacitor bottom is provided with blower fan 7; The second layer is provided with L2 reactor 8 and secondary installing Slab element 5, and secondary installing Slab element 5 is arranged on power cell 2 bottom; Third layer is provided with L1 reactor 9, filter capacitor 10; Bottom is provided with main contactor 11 and breaker unit 4, and be provided with protective plate 3 in described cabinet 1 front cabinet door, power cell 2 outside is provided with protective cover; The circuit board of described secondary installing Slab element 5 is coated with three anti-enamelled coatings.

Protective plate 3 and protective cover all adopt degradable nonmetallic materials to make, and by laser engraving technique once-forming, are suitable for a small amount of processing, low processing cost compared with mold.

Power cell 2 comprises IGBT module, drives keyset, radiator, wherein, IGBT module is connected with driving keyset, and IGBT module all passes through radiator heat-dissipation with driving keyset, described radiator is made up of the heating panel of several dentalations, sees Fig. 6, Fig. 7.

According to main circuit schematic diagram, grid bus is by circuit breaker Q F1(breaker unit 4) inlet wire, circuit breaker Q F1 and label 11 in main contactor KM1(Figure 10) be connected, the output of main contactor KM1 is connected with net side inductance L 4, net side inductance L 4 three-phase output end connects inverter side electric capacity L1 respectively, L2, L3(DC capacitor unit 6), net side inductance L 4 three-phase output end and inverter side electric capacity L1, L2, be connected with filter capacitor CF(between L3 and see Fig. 4, 5, 9), inverter side electric capacity L1, L2, L3 output respectively with current sensor HAT1, HAT2, HAT3 is connected, current sensor HAT1, HAT2, HAT3 is connected with three-phase converter module 2 respectively, described main contactor KM1 is parallel with charging contactor KM2, grid bus earth connection is connected with filter capacitor CF, three-phase converter module 2.

Blower fan 7 is arranged on the middle part of cabinet 1, air enters in cabinet by the ventilating blind being arranged on cabinet 1 bottom, blower fan 7 extracts the air of cabinet 1 bottom surrounding, blow to cabinet 1 top to dispel the heat, finally discharged by hot-air by louver(-vre), blower fan 7 is arranged in the middle part of cabinet 1 and achieves the ventilation of malleation low noise and high efficiency and heat radiation.

The detection algorithm that the quality of power supply utilizing said apparatus to realize regulates, comprises the following steps:

1) instantaneous value of three-phase voltage and electric current is established to be respectively e _a, e _b, e _cand i _a, i _b, i _c, they are carried out the conversion of abc/ alpha-beta, under being transformed into the orthogonal rest frame of alpha-beta two-phase, two-phase instantaneous voltage e can be obtained _α, e _βwith two-phase transient current i _α, i _β, see Figure 12:

$\left[\begin{array}{c}{e}_{\mathrm{\α}}\\ e_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{e}_a\\ e_b\\ e_c\end{array}\right]---\left(1\right)$

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{i}_a\\ i_b\\ i_c\end{array}\right]---\left(2\right)$

In formula (1), (2) $C_{2/3}=\sqrt{2/3}\left[\begin{array}{ccc}1& -1/2& -1/2\\ 0& \sqrt{3}/2& -\sqrt{3}/2\end{array}\right];$

2) formula (3) is defined to obtain according to active power p and reactive power q

$\left[\begin{array}{c}p\\ q\end{array}\right]=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right]=C_{\mathrm{pq}}\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]---\left(3\right)$

In formula (3) $C_{\mathrm{pq}}=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right];$

3) active power p, reactive power q obtain formula (4) through low pass filter LPF

Wherein for instantaneous active power, for instantaneous reactive power, 3E is three-phase instantaneous voltage, I ₁for transient current, for phase angle;

4) by sensed current i can be calculated _a, i _b, i _cin fundametal compoment i _af, i _bf, i _cf

$\left[\begin{array}{c}{i}_{\mathrm{af}}\\ i_{\mathrm{bf}}\\ i_{\mathrm{cf}}\end{array}\right]=C_{3/2}{C}_{\mathrm{pq}}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]=\frac{1}{{3E}^2}{C}_{3/2}{C}_{\mathrm{pq}}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]---\left(5\right)$

By i _af, i _bf, i _cfrespectively with i _a, i _b, i _csubtract each other, can i be drawn _a, i _b, i _charmonic component i _ah, i _bh, i _ch.Wave superposition theory diagram can be set up, see Figure 13, in figure:

E _a, e _b, e _c-input voltage instantaneous value;

I _a, i _b, i _c-input current instantaneous value;

I _ah, i _bh, i _ch-output current;

Park conversion-dq converts;

LPF-low pass filter;

Kp-real component;

Kq-idle component;

Ka, Kb, Kc-current coefficient;

Function control mode:

Independent idle control-SVG:Kp=0, Ka=0, Kb=0, Kc=0, Kq=1;

Independent harmonic controling-APF:Kp=1, Ka=1, Kb=1, Kc=1, Kq=1;

Comprehensive Control SVG+APF-Kp=1, Ka=1, Kb=1, Kc=1, Kq=0.

5) by sensed current i can be calculated according to formula (6) _a, i _b, i _cin fundamental active component i _apf, i _bpf, i _cpf

$\left[\begin{array}{c}{i}_{\mathrm{apf}}\\ i_{\mathrm{bpf}}\\ i_{\mathrm{cpf}}\end{array}\right]=C_{2/3}{C}_{\mathrm{pq}}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ 0\end{array}\right]---\left(6\right)$

Then sensed current i _a, i _b, i _charmonic current and reactive current sum is with the difference of fundamental active current.

Tool of the present invention has the following advantages:

1, same device, under Systematical control, can realize SVG(static reacance generator respectively) or APF(Active Power Filter-APF) function, also can realize SVG and APF function, namely the design takes into account the functional requirement of SVG or APF simultaneously from hardware and software simultaneously.The multiple power quality problems such as the harmonic wave simultaneously changed in automatic tracking and compensating electrical network, idle, negative phase-sequence.It is that 2 ~ 50 subharmonic filtering gamuts are effective that SVG range of operation reaches-100% ~+100%, APF filter range, and free function is arranged;

2, power cell and direct current capacitor unit design for split-type structural, are easy to realize dilatation respectively;

3, adopt modularized design, power density is high, and volume is little, and reduce and connect busbar length, namely non-ferrous metal consumption is little;

4, adopt mean value carrier modulation technique, equipment itself does not produce humorous wave interference;

5, adopt the protective plate of degradable nonmetallic materials, achieve the isolating and protecting of major loop and control system, be i.e. dust-proof, damp proof, Defend salt fog and antistatic.Meanwhile, the smooth and easy and security of operation of ventilation and heat is ensured;

6, major loop and control system have employed secondary installing Slab element structural design and achieve and shield worn-out the isolation, electromagnetism interference;

7, built-in blower fan, can realize malleation low noise and ventilate and high efficiency and heat radiation;

8, rack is upper and lower, is all designed with inlet wire jockey, realization can inlet wire entirely compatible.

9, fast response time, the response time: SVG is less than 5ms, APF is less than 1ms;

10, back-up system automatic current limiting operation function.

Claims (1)

1. the detection algorithm of a quality of power supply adjustment, active power quality comprehensive regulating device is adopted to realize, described active power quality comprehensive regulating device comprises cabinet, power cell, protective plate, breaker unit, secondary installing Slab element, DC capacitor unit, blower fan, L1 reactor, L2 reactor, filter capacitor, contactor, secondary installing Slab element supports fixing by secondary installing plate, secondary installing plate is made by sheet metal; Cabinet top is provided with louver(-vre), and bottom is provided with ventilating blind, and the front of cabinet outside is provided with cabinet door, and cabinet upper rear portion and bottom are equipped with inlet wire plate; Be divided into four-layer structure in cabinet, ground floor is provided with power cell, DC capacitor unit, blower fan, and power cell and DC capacitor unit are split-type structural, and power cell is arranged on cabinet front near cabinet door place, and DC capacitor unit bottom is provided with blower fan; The second layer is provided with L2 reactor and secondary installing Slab element, and secondary installing Slab element is arranged on power cell bottom; Third layer is provided with L1 reactor, filter capacitor; Bottom is provided with contactor and breaker unit, and be provided with protective plate in described cabinet front cabinet door, power cell outside is provided with protective cover; Described protective plate and protective cover all adopt resin material to make;

It is characterized in that the detection algorithm that the described quality of power supply regulates comprises the following steps:

1) instantaneous value of three-phase voltage and electric current is established to be respectively e _a, e _b, e _cand i _a, i _b, i _c, they are carried out the conversion of abc/ alpha-beta, under being transformed into the orthogonal rest frame of alpha-beta two-phase, two-phase instantaneous voltage e can be obtained _α, e _βwith two-phase transient current i _α, i _β:

$\left[\begin{array}{c}{e}_{\mathrm{\α}}\\ e_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{e}_a\\ e_b\\ e_c\end{array}\right]---\left(1\right)$

$\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=C_{2/3}\left[\begin{array}{c}{i}_a\\ i_b\\ i_c\end{array}\right]---\left(2\right)$

In formula (1), (2) $C_{2/3}=\sqrt{2/3}\left[\begin{array}{ccc}1& -1/2& -1/2\\ 0& \sqrt{3}/2& -\sqrt{3}/2\end{array}\right];$

2) formula (3) is defined to obtain according to active power p and reactive power q

$\left[\begin{array}{c}p\\ q\end{array}\right]=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right]\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]=C_{pq}\left[\begin{array}{c}{i}_{\mathrm{\α}}\\ i_{\mathrm{\β}}\end{array}\right]---\left(3\right)$

In formula (3) $C_{pq}=\left[\begin{array}{cc}{e}_{\mathrm{\α}}& e_{\mathrm{\β}}\\ e_{\mathrm{\β}}& -e_{\mathrm{\α}}\end{array}\right];$

3) active power p, reactive power q obtain formula (4) through low pass filter LPF

Wherein for instantaneous active power, for instantaneous reactive power, 3E is three-phase instantaneous voltage, I ₁for transient current, for phase angle;

4) by sensed current i can be calculated _a, i _b, i _cin fundametal compoment i _af, i _bf, i _cf:

$\left[\begin{array}{c}{i}_{af}\\ i_{bf}\\ i_{cf}\end{array}\right]=C_{3/2}{C}_{pq}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]=\frac{3}{3E^2}{C}_{3/2}{C}_{pq}\left[\begin{array}{c}\stackrel{\‾}{p}\\ \stackrel{\‾}{q}\end{array}\right]---\left(5\right)$

5) by sensed current i can be calculated according to formula (6) _a, i _b, i _cin fundamental active component i _apf, i _bpf, i _cpf:

$\left[\begin{array}{c}{i}_{apf}\\ i_{bpf}\\ i_{cpf}\end{array}\right]=C_{2/3}{C}_{pq}^{-1}\left[\begin{array}{c}\stackrel{\‾}{p}\\ 0\end{array}\right]---\left(6\right)$

Then sensed current i _a, i _b, i _charmonic current and reactive current sum is with the difference of fundamental active current.