A High Energy Saving Interface System Using a Matrix Converter between a Power Grid and an Engine Generator for Bio Diesel Fuel

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1 A Hgh Energy Savng Interface System Usng a Matrx Converter between a Power Grd and an Engne Generator for Bo Desel Fuel Jun-ch Itoh, Member, IEEE, Hrok Takahash, and Junnosuke Haruna, Student Member, IEEE Nagaoka Unversty of Technology, Jaan Abstract--Ths aer dscusses an nterface ower converter between a ower grd and an engne generator. A matrx converter, whch s one of the AC/AC drect converters, can acheve hgh effcency wthout large energy storages. Therefore, the volume of the converter becomes smaller and the relablty of the nterface system s mroved due to no use of electrolytc caactor. Ths aer dscusses the control strategy of a matrx converter for the ower grd nterconnecton. In addton, the erformances are demonstrated by smulaton and exerments wth a.5-kw rototye. The roosed control method s confrmed n the smulaton and exermental results. Furthermore, the maxmum effcency of 96.8 % s obtaned n the exerment. Total loss of the ower converter s aroxmately half of the conventonal system that s usng a Back-to-Back converter. Index Terms--matrx converter, BDF, BTB converter, nterface ower converter, generator I. INTRODUCTION The studes and actvtes about a smart grd are hghly conductng recently because ths concet could acheves hgh energy savng. Bo Desel Fuel (BDF) s one of renewable energy resources. BDF s used for a desel engne wth a generator for electrc ower converson. BDF has smlarty to the wnd turbnes and hotovoltac cell systems n term of the carbon neutral. However, an engne generator can rovde more stable ower n comarson to the generaton system that uses the natural energy resources such as a solar ower, a wnd turbne and other. Moreover, the bomass fuel whch s tyfed as a BDF does not nfluence human health and envronmental. Therefore, an engne generator usng BDF s exected to aly n a smart grd n the future. In the smart grd, an nterface ower converter s requred between an engne generator and a ower grd. Ths nterface ower converter adjusts the frequency and the voltage amltude on both sdes. The nterface converters for the alcaton of smart grd are exected to have hgh effcency and hgh relablty. Generally, a back-to-back (BTB) converter, whch conssts of a PWM rectfer and a PWM nverter, s aled n ths system as the nterface converter. However, the BTB converter uses large amount of electrolytc caactors as the smoothng caactors. As the results, the system sze s bg and regular mantenance s requred. That s, the electrolytc caactors reduce the system relablty. Moreover, the effcency of the BTB converter s low due to the two stages ower converson wthn the converter. Recently, matrx converters attract a lot of attentons among the researchers because ths converter acheves hgh effcency and small sze due to no smoothng caactors. Therefore, the system wth matrx converter s exected to acheve hgh relablty and long-lfe tme. Many aers regardng to the matrx converter are beng dscussed n the feld of adjustable seed drve alcatons [-4]. On the other hand, only small ortons of the aers descrbe usng the matrx converter as a generator nterface converter n a dstrbuted ower suly and a mcro grd system, whch dscuss on the subjects of hgh effcency and mantenance ssue. In these aers, a matrx converter s aled to the nterconnecton system to adjust the frequency and voltage amltude between the generator and the grd system. In Ref. [5-8], the control of the generator ower based on the generator arameters are beng dscussed. The control method has to be changed regularly because t deends on the tyes and arameters of the generator. On the other hands, BDF generators are formed by many knds of generators such as an nducton generator, a synchronous generator and a ermanent magnetc generator. These generators show a dfference n terms of cost and feld requrements uon to the crcumstances. Due to the varetes of generators, desgn becomes comlcated and therefore a robust nterface converter s requred. Ths aer rooses to aly the matrx converter as an nterface converter between the ower grd and a desel engne wth BDF. The key feature of ths roosed system s that the matrx converter can control the generator ower, regardless of the generator arameters and tyes. In the roosed control, the generator s assumed as a smle varable amltude and frequency ower suly wth the nternal medance. Then, a current regulator n the generator sde controls the nut flter current. As a result, the roosed system can connect voltage source at the both nut and outut sde. In ths aer, frst, the feature of the roosed nterface system s ntroduced. Second, the control strategy of the matrx converter for the nterface converter s descrbed. Fnally, the smulaton results and also the exermental results whch are obtaned from a.5-kw rototye are demonstrated

2 2 accordngly. II. SYSTEM CONFIGURATION Fgure shows an nterconnecton system usng an nterface converter among a BDF generator, a load and a ower grd. the conventonal nterface converter between an engne generator and the ower grd. In order to connect a generator to the ower grd, the nterface converter must rovde a generator ower n ste of the dfferences of the frequency, hase and voltage amltude between the generator and the ower grd. In addton, the nterface converter controls the actve ower accordng to the load demands. From here, these nterface converters are used to satsfy the above requrements. An engne generator usng the BDF s usually oeratng at a constant seed for obtanng a constant outut ower. Therefore, the oeraton condton of the generator can be set to the hghest effcency condton. Fgure 2 (a) shows a conventonal system usng a BTB converter. The PWM nverter needs to control the nterconnecton current to snusodal waveform for the grd. On the other hand, the PWM rectfer needs to control the generator current to snusodal waveform. Both nut and outut of the BTB converter do not nterfere wth each other because the smoothng caactors n the DC lnk could searate the controls. Therefore, the nterconnecton current and the generator can be controlled easly. As a result, a BTB converter s usually used as an nterface converter. On the other hand, the roblems of ths system are as followng; the smoothng caactor n DC lnk s bulky; the smoothng caactor s the shortest lfe-tme element n the system; the system effcency becomes lower because of two tmes converson between the generator and the ower grd. Fgure 2 (b) shows a conventonal system wth a matrx converter usng nne bdrectonal swtches as an nterface converter. The smoothng caactor s not requred because the matrx converter has no DC stage. In addton, the matrx converter can acheve the mnmum loss due to only one stage converson n term of AC to AC converson. The ower loss of the matrx converter s aroxmately half of that of the BTB system [9]. However, these conventonal nterface systems n Fgure 2 have another roblem n term of the generator control. In order to control the ower from a generator, the generator arameters frst must be desgned and known. The most common generators seen n ths alcaton are such as the nducton generator, the synchronous generator wth external excter, or the ermanent magnetc generator. Therefore, t s comlcated to change the control methods accordng to the generators, esecally n a low cost system. Fgure 3 shows the roosed nterconnecton system wth a matrx converter. A LC flter s added between the generator sde and the nut lne of the matrx converter. The generator ower s controlled by adjustng the nut flter current nstead of the generator current. The generator current s decded by the amltude and hase angle of the nut flter caactor current. The matrx converter can control the flter reactor Fg.. Confguraton dagram of an nterconnecton system usng an nterface converter for a smart grd. BDF generator G Current Inut flter (a) BTB converter Matrx converter Outut flter Voltage Interconnecton Reactor Power grd (b) Matrx Converter Fg. 2. Confguraton dagram of the conventonal ower grd connected system usng a ower converter. BDF Generator G Voltage Inut flter Matrx converter Current Outut flter Power grd Fg. 3. Confguraton dagram of the roosed ower grd connected system usng a matrx converter. current wth the control block dagram by not usng the generator arameters, such as nternal medance and back electromotve force of the generator. Moreover, the oeratng seed and hase angle of the generator from ts encoder are unnecessary because the actve ower can be controlled by the detecton of the generator termnal voltage from the nut flter caactors. As a result, the generator can be assumed as a smle varable frequency ower suly wth nternal medance. From ths, all tyes of generator, esecally a very low cost generator, can be used n ths system. However, the roosed nterface system has techncal

3 3 ssues n term of the nterconnecton. The matrx converter controls both nut and outut waveforms at the same tme. Therefore, the nut sde control affects the outut sde control due to the lack of energy buffer, whch s dfferent from a BTB converter. Therefore, f the generator termnal voltage and current are dstortng, the fluctuaton wll affect the ower grd condtons. In addton, the roosed system uses LC flters at both nut and outut sdes, whch the resonance between L and C s ossble to occur at both sdes. The resonance n the outut sde s suressed by the damng resstor and the resonance n the nut sde s suressed by voltage and current feedback control whch wll be descrbed n next chater. On the other hand, the matrx converter must comensate the load ower even f a trouble such as nterruton occurs at the ower grd. When the trouble occurs at the ower grd, crcut breakers shown n the Fgure are oened. Therefore, the matrx converter must control the load ower usng the ower rovded from the generator only. Thus, the control for ndeendent oeraton of the matrx converter s requred n case a trouble occurs at the ower grd. e g L g g q v c d q L v mc g c g Fg. 4. Relatonsh among the voltages and the currents on the generator sde wth dq axs based on the termnal voltage and γδ axs based on the back electromotve force of the generator. d III. CONTROL STRATEGY There are two tyes of ower source n a matrx converter known as, the voltage and current source. Usually, the voltage s connected to reactors, and the current sde s connected to caactors. In general, the current s located on the voltage ower source.e. a ower grd. In an adjustable seed drve system, the current s located on the ower grd sde. In the roosed system, however, the current of the matrx converter s connected to the ower grd, whch s treated as a load sde. That s, ths system s oerated smlar to the regeneraton mode of an adjustable seed drve system. The generator sde becomes the voltage alke a voltage source nverter. The reactor current and the caactor voltage n the nut flter are controlled by the roosed method. Note that the nut voltage of the matrx converter s lower than 86.6% of the ower grd voltage because of the lmtaton n the voltage transfer rato of a matrx converter. In other words, the roosed system boosts u the generator termnal voltage. Thus, the matrx converter of the roosed system can oerate even f the generator voltage lowers due to the generator frequency fluctuaton. On the other hand, the conventonal nterface system usng a matrx converter such as Fgure 2 (b) has the lower lmtaton of the generator termnal voltage whch the matrx converter can oerate at, because of the lmtaton of the voltage transfer rato. Fgure 4 shows the relatonsh between the γδ and the dq axs to consder the actve ower and reactve ower on the roosed control. Note that γδ axs s based on the back electromotve force of the generator and dq axs s based on the termnal voltage of the generator. In Fgure 4, e s the back electromotve force vector of the generator, g s the generator current vector, c s the caactor current vector, v c s the Fg. 5. Control block dagram of the roosed nterface system between an engne generator and the ower grd. voltage vector of the nut flter caactor, s the current vector of the nut flter reactor, v mc s the nut voltage vector of the matrx converter, L s the voltage dro vector at the nut flter reactor, and L g g s the voltage dro vector at the generator nductance. Note that s a dfferental oerator. Generally, the dq axs s based on the back electromotve force of the generator. In ths aer; however, the termnal voltage of the generator s defned as the bass of the dq axs. These axes are obtaned from the rotatng frame and rotate at the same seed. Fgure 5 shows the roosed control block dagram. The actve and reactve current controls are mlemented on the rotatng frame. The drecton of the q-axs s defned as the same drecton of the nut flter caactor voltage. The actve and reactve ower on the dq axs s ndcated by dq = v c = vcdd + vcqq () qdq = v c = vcdq vcqd where dq s the actve ower, q dq s the reactve ower of the nut of the matrx converter. The drecton of the voltage vector of the nut flter caactor conforms to the q-axs. Then, () s calculated by

4 4 dq = vcqq (2) qdq = vcqd Therefore, t s shown that d s the reactve current and q s the actve current on the dq axs. That s, the d-axs current command d controls the reactve ower; the q-axs current command q controls the actve ower on the dq axs. Ths current control s mlemented wth an automatc current regulator (ACR). The outut and nut hase angles are calculated by the arctangent functon resectvely. The dq axs s obtaned by the detected voltage of the nut flter caactor. However, the γδ axs cannot be obtaned wthout the nformaton from the generator encoder. Therefore, the roosed system adots the dq axs to control the generator ower. A low-ass flter (LPF) s necessary after thegenerator voltage detecton because the flter caactor voltage v cr, v ct may contan dstortons due to the LC resonant. Note that the resonant suresson control s aled wth an ACR. The voltage control of the caactor s not necessary because the caactor voltage s clumed by the generator voltage. The control of the matrx converter s aled wth a vrtual AC/DC/AC PWM carrer comarson method []. The control of the ower grd current and the control of the nut voltage are searated by usng a vrtual rectfer command and a vrtual nverter command n ths method. As a result, the control becomes smle. The ower grd sde can obtan a unty ower factor. Fgure 6 shows the vector dagram on the generator sde when the generator current vector and the back electromotve force vector of the generator are n the same hase. Note that the current of the nut flter caactor s assumed to be zero for smlcty because the caactor current s small suffcently. Therefore, the generator current vector conforms to the nut current vector of the matrx converter. The actve ower P γδ on the γδ axs s obtaned by q γδ = e g = vcq cosφ = dq (3) cosφ where φ s the hase angle between the dq axs and the γδ axs because of the nternal medance of the generator. The actve ower on the γδ axs s equal to the actve ower on the dq axs. Therefore, the actve current command d s calculated by dq q = (4) v cq When the generator current vector and the voltage vector of the back electromotve force are n the same hase, the cuer loss of the generator becomes the least because the generator rovdes no reactve current on the γδ axs. The mnmum cuer loss s acheved when the reactve current of the generator gγ becomes zero. The matrx converter controls gγ to zero by adjustng the reactve current command d on the dq axs. d s calculated by d 2 L q X vcq = (5) 2 e δ where X L s the reactance of the generator. Thus, dervaton of Fg. 6 The vector dagram on the generator sde when the generator current vector and the voltage vector of the back electromotve force of the generator are n the same hase. d q Destnaton flter + st v cd v cq PI controller v d st sl K + st + st dam + st dam v q q K + st + st st sl K d K d Control v cd v cq d Feed forward term damng control Crcut Inut flter reactor Fg. 7. Transfer functon block dagram n ACR to control the nut current of the matrx converter. d usng (5) must use the generator arameters. Equaton (5) cannot be used n the control of the matrx converter because the key feature of the roosed system s that the matrx converter controls ower from the generator wthout the generator arameters. However, t s useful for the generator effcency to control d. Therefore, the maxmum ower ont trackng (MPPT) method whch s aled to the generaton system wth the natural energy resources must be consdered. Fgure 7 shows a control block dagram whch s used for the control of the nut current. The control strategy n Fgure 7 does not use the generator arameters. The destnaton flter s used to revent overshoot n the nut current. The gan values of the PI controller are decded from natural angler frequency ω n and the damng factor ζ.

5 5 In addton, a feed forward term s aled nto the damng control to suress the LC resonant at the PI outut. The feed forward term means the voltage of the nut flter caactor. It s effectve for stable oeraton on the generator sde to suress the voltage rle of the nut flter caactor. In Fgure 5, the fundamental frequency comonent of the nut flter caactor s converted to a constant value alke a DC comonent by the rotatng frame. On the other hand, the resonant comonent of the nut flter caactor s converted to rle comonent. In the damng control for the feed forward term n Fgure 7, frst, low ass flters, whch have the tme constant T dam, searate the DC and rle comonents of the voltage of the nut flter caactor. Then only the rle comonent s multled by a damng gan K d. As a result, the comensated value for the rle due to LC resonant s obtaned. IV. SIMULATION AND EXPERIMENTAL RESULTS At frst, the roosed system s evaluated n smulatons n robable stuatons for the nterconnecton between an engne generator and the ower grd. Table shows the generator arameters. Note that the generator s assumed as a voltage source and a large reactor (5%) to evaluate the valdty of the roosed system n rncle. Table 2 shows the smulaton condtons. Fgure 8 shows the oeraton waveforms of the roosed system wth only actve current command ( q =.u.) at steady state. The nut current of the matrx converter s controlled to rated current 4 A (RMS) by the ACR. The unty ower factor s obtaned on the ower grd and the generator sde. The unty ower factor on the ower grd sde s obtaned easly by the oen loo control from the vrtual current source rectfer. On the other hand, the unty ower factor on the generator sde s obtaned by the ACR wth no reactve current command ( d =.u.). In addton, both the grd current and nut current obtan snusodal waveforms. Thus, the feature of the roosed method, that s the smultaneous control on the nut and outut sde wthout a DC lnk s confrmed. Fgure 9 shows the relatonsh between a zero ont of the γ-axs current gγ and the nut current commands of the matrx converter. Note that back electromotve force of the generator s set to V rms (lne to lne), the generator frequency s set to 6 Hz n Fgure 9. The dq axs current d and q are through a LPF for observaton. The matrx converter controls the nut ower factor wth the reactve current command d. Note that the actve current command q s a constant value and rovdes constant actve ower to the ower grd. When the reactve current gγ on the γδ axs s zero, the reactve current d on dq axs s -.43.u.. Note that the theoretcal value of d usng (5) s -.55.u. when gγ s zero. The generator current s referred to be a small value because the amltude of the generator current affects coer loss of the generator. In other words, t s requred to control gγ to zero by adjustng d. Fgure shows the matrx converter waveforms whch s oerates under a startng sequence. The startng sequence s TABLE. GENERATOR PARAMETERS. Rated termnal voltage (lne to lne) Rated back e.m.f. (lne to lne) Rated current Rated ower Rated seed Rated frequency 76 V rms 5 V rms 4 A rms (=.u.) 3.7 kw 8 rm 9 Hz ole 6 Synchronous nductance 6.56 mh (5 %) TABLE 2. SIMULATION CONDITIONS. Grd voltage (lne to lne) Grd frequency Generator back e.m.f. (lne to lne) Generator frequency MC rated nut ower MC rated nut voltage (lne to lne) Carrer frequency Grd sde LC flter Grd sde damng resstor Generator sde LC flter 2 V rms 5 Hz 5 V rms 9 Hz 5.5 kva 73 V rms khz 2 mh (2.35 %) 3.2 µf 47 Ω (ζ=.3) 2 mh (5.2 %) 6.6 µf ACR damng factor ζ.7 ACR natural angular frequency ω n 4 rad/s Fg. 8. Oeraton waveforms of the matrx converter n the roosed system at steady state n smulaton. -d_ref_u gq_u gd_u -d_u_lf Fg. 9 Relatonsh between a zero ont of the γ-axs current and the nut current command of the matrx converter.

6 6 lke followng; contactors on the generator sde n Fgure are closed. Then, the matrx converter starts to oerate wth zero current commands. After that, the current commands are fed nto the ACR. From to ms, the generator s not connected to the matrx converter. The generator s already oeratng at ths erod. However, the matrx converter does not oerate. At ms, contactors on the generator sde n Fgure are closed to connect the generator and the matrx converter. After ths, the resonant current due to the nternal medance of the generator and nut flter caactor occurs. Note that the matrx converter blocks off all the gates of IGBTs from to 3 ms. At 3 ms, the matrx converter starts to control the nut current to zero by the ACR. The LC resonant s suressed by the damng control n the ACR. Then, at 5 ms, a ram current command s nutted to suress the surge voltage on the nut flter caactor. As a result, the generator connecton s enabled by the above sequences. The generator termnal voltage angle θ n calculaton for ACR s mortant for stable control n the transent state. However, there s no surge current excet LC resonant current n the transent erod. Therefore, f the LPF for θ n calculaton elmnates the frequency band over the rated generator frequency, the ACR can start to oerate stably rght after the generator connecton. Fgure shows the generator frequency fluctuaton wth constant nut current commands. The generator termnal voltage becomes lower as the generator frequency fluctuates because the back electromotve force of a generator s roortonal to the oeratng seed. Durng the fluctuaton erods, the voltage and current on the grd sde have no dstorton. The dstorton due to the generator frequency fluctuaton does not occur because the fundamental frequency current of the nut flter reactor s controlled as a DC comonent based on the converson from the rotatng frame. Furthermore, the oeraton also confrms no fluctuaton on the grd ower factor. Note that the grd current s reduced because of the nut ower change due to the constant nut current commands and voltage fluctuaton. Moreover, the constant ower control s avalable f the nut current commands are generated wth the ower commands. Fgure 2 shows the oeraton waveforms where the ower grd voltage s fluctuatng. Note that the electromotve force of the generator s set to V rms (lne to lne), the frequency of the generator s set to 6 Hz. The nut current s controlled to a constant value because of the ACR aganst the fluctuaton of the grd voltage. On the other hand, the grd current ncreases aganst the fluctuaton of the grd voltage. Therefore, the matrx converter can control the generator ower constantly when the grd voltage fluctuates. As mentoned revously, however, when a trouble occurs at the ower grd such as nterruton, the crcut breakers n Fgure are oened. Therefore, the control method of the matrx converter s needed to study n the stuaton where an ndeendent oeraton condton n the roosed system s requred. A.5-kW rototye crcut was constructed and tested wth the roosed system to evaluate the effcency. The exermental condtons are almost the same as Table 2. Note gu -d_ref_u -d_u u_ob -q_u -q_ref_u Fg.. Voltage and current waveforms on the generator sde n the startng sequence of the roosed nterface system. 8 vcu Vr r_ob Generator seed rm/dv Generator termnal voltage (hase) 5 V/dv Grd voltage (hase) V/dv Grd current 5 A/dv 2 ms/dv Fg.. Oeraton waveforms of the roosed system ncludng no dstorton n the erod of the generator frequency fluctuaton. Vr r_ob u_ob Fg. 2. Oeraton waveforms of the roosed system n erod of the fluctuaton of the ower grd voltage.

7 7 that the generator was relaced wth a voltage source and a transformer because of the exermental lmtaton. The voltage source s 3 V rms (lne to lne) and the frequency s 5Hz. Then, the damng control n Fgure 7 was not used n the exerment. Instead, the damng resstor 5. Ω was nserted n seres to the flter caactors on the generator sde to confrm the basc characterstc of the PI controller n the ACR. The ACR gan and damng factor s adjusted accordng to exermental arameters. Fgure 3 shows the steady state oeraton waveforms of the rototye. Note that only actve current command q s fed nto the ACR. Snusodal waveforms are confrmed to obtan n the nut current and grd current. The unty ower factor on the nut sde of the matrx converter s obtaned and the grd ower factor s 98.6 %. The remanng dstorton n the current waveform s generated from the voltage error due to the commutaton. Therefore, the qualty of the current waveform wll be mroved by alyng a voltage error comensaton method [-2]. Fgure 4 shows the measurement results of the effcency. Note that the effcency s measured n a way ooste to the ower flow because of the exermental lmtaton. The effcency of over 96 % s obtaned from over a 3% load; the maxmum effcency s 96.8% at a 4 W load. In general, the effcency of the BTB s aroxmately 92% - 94%. The total loss n the ower converter s reduced to /2 of that of a BTB n the roosed system. V. CONCLUSIONS Ths aer dscusses an nterface converter between an engne generator and a ower grd. The matrx converter s used as the nterface converter n order to obtan hgh effcency, relablty and sze reducton n comarson to a BTB converter. The roosed nterface system s characterzed by the generator sde control. The smulaton results and exermental results confrmed the valdty of the roosed system. In the smulatons, the control of the nut current of the matrx converter s confrmed for an nterconnecton system. The maxmum effcency 96.8% s demonstrated n the aer. Total ower converter loss becomes aroxmately half of the conventonal converter loss. In future work, the current waveforms wll be mroved and other tye of exermental results ncludng transent resonse and revaluaton of the system effcency wll be consdered. In addton, the control of the matrx converter n case of the nterruton wll be nvestgated. REFERENCES [] I. Sato, J. Itoh, H. Ohguch, A. Odaka and H. Mne: An Imrovement Method of Matrx Converter Drves Under Inut Voltage Dsturbances, IPEC-Ngata, (25) [2] E. Wechmann, P. Burgos and J. Rodrguez: Contnuously Motor- Synchronzed Rde-Through Caablty for Matrx-Converter Adjustable-Seed Drves, IEEE Trans., Vol.49, No.2,.39 (22) [3] J. Lettl: Matrx Converter Inducton Motor Drve, EPE-PEMC, (26) Generator termnal voltage (hase) 25 V/dv Matrx converter nut current Grd voltage (hase) 25 V/dv Grd current 5 A/dv A/dv ms Fg. 3. Oeraton waveforms of the roosed system at steady state wth an exerment. Effcency Fg. 4. Effcency characterstcs wth exerment. [4] F. Blaabjerg, D. Casade, Chrstan Klumner and M. Matten: Comarson of Two Current Modulaton Strateges for Matrx Converters Under Unbalanced Inut Voltage Condtons, IEEE Trans., Vol.49, No.2, (22) [5] P. W. Wheeler, J. C. Clare and P. Zanchetta: A Three-Phase Utlty Power Suly Based on the Matrx Converter, IAS, (24) [6] H. Nkkhajoe and M. Reza Iravan: A Matrx Converter Based Mcro- Turbne Dstrbuted Generaton System, IEEE Trans., Vol.2, No.3, (25) [7] C.-W. Hsu, C.-T. Lee and P.-T. Cheng: A Low Voltage Rde-Through Technque for Grd-Connected Converters of Dstrbuted Energy Resources, ECCE2, (2) [8] J. Haruna and J. Itoh: Behavor of a Matrx Converter wth a Feed Back Control n an Inut Sde, IPEC-Saoro, 23I-5, (2) [9] J. Itoh, I. Sato, A. Odaka, H. Ohguch, H. Kodach, and N. Eguch: A Novel Aroach to Practcal Matrx Converter Motor Drve System Wth Reverse Blockng IGBT, IEEE Transactons on Power Electroncs, Vol. 2, No.6, (25) [] A. Odaka, I. Sato, H. Ohguch, Y. Tama, H. Mne, J. Itoh: A PAM Method for Matrx Converter Based on Vrtual AC/DC/AC Converson Method, IEEJ Trans., Vol.25, No.9,.85-9 (26) [] H. Ohguch, J. Itoh, I. Sato, A. Odaka, H. Kodach and N. Eguch: Imrovement Schemes of Control Performance for Matrx Converter, EPE Journal Volume 7-2 (24) [2] K. Kato and J. Itoh: Develoment of a Novel Commutaton Method whch Drastcally Suresses Commutaton Falure of a Matrx Converter, IEEJ Trans., Vol.27-D, No.8, (27)