Summary of NX6
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Vacon nx ac drives design guide hybridization ®.
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Vacon • 1 24-hour support +358 (0)201 212 575 • email: service@vacon.Com table of contents document id:dpd01887 revision release date: 24.10.2016 1. Basics ........................................................................................................................ 2 1.1 power or energy s...
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1 vacon • 2 basics tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 1. Basics the basic idea is always to achieve energy and/or power management of common point of coupling. Typical use cases are • time shift for production • peak load shaving for distribution • smoothen load for average energy • ba...
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Basics vacon • 3 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 1 1.1 power or energy storage it is important to distinguish the system’s "nature", that is, whether it is a power application or an energy application. Another relevant thing to note is the dynamic requirements of the a...
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1 vacon • 4 basics tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 3. Comparision of battery systems table 1. Comparision of battery systems # reference # reference a batteries e li-ion b pb f double layer capacitors c nicd g electrolytic capacitors d nimh battery type energy density wh/kg p...
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Basics vacon • 5 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 1 © electricity storage association figure 4. System ratings 1.2 battery current dimensioning in a battery, the nominal current is denoted with c. For example, a 10ah 1c current would be 10a. In some cases, the below rat...
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2 vacon • 6 basic topologies for connection tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 2. Basic topologies for connection the basic connections are divided into multible possibilities. Table 2. Basic connections use case topology pros cons common dc energy storage connection • no competitive "...
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Basic topologies for connection vacon • 7 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 2 energy storage close to load and ac-grid with direct dc-link connection • load power/ energy support close the consumption • large number of components • efficiency • size • power vs. Energy di...
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3 vacon • 8 special characteristics affecting the tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 3. Special characteristics affecting the selection different chemistry causes different behavior in cell voltage as a function of charge/discharge and soc (state of charge). This creates "voltage windo...
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Special characteristics affecting the selection vacon • 9 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 3 figure 6. Battery voltage change as a function of state of charge (soc) the voltage window is important also from the process dynamics point of view. If we expect the battery sy...
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3 vacon • 10 special characteristics affecting the tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 the difference in the cases is that the battery size in energy is changed from 6 strings in parallel to one string in parallel. This will lead in higher c-rates in the battery having smaller amount of...
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Special characteristics affecting the selection vacon • 11 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 3 3.2 galvanic isolation requirement the pulse width modulation (pwm) produces common mode voltage. Because every phase (a, b and c) can be connected only either to positive dc-b...
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3 vacon • 12 special characteristics affecting the tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 10. Simulated cm-voltage, u dc =1025v, fsw=5khz. Because of the common mode dc-link starts to jump compared to ground. Main frequency for this jumping is switching frequency but also higher fre...
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Special characteristics affecting the selection vacon • 13 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 3 figure 11. Dc+ to ground voltage. On the left u dc = 1200 v, on the right 800 v. The battery system does not withstand unfiltered common mode voltage. Because pwm modulation is...
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3 vacon • 14 special characteristics affecting the tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 13. Lcl ground capacitor must be disconnected 3.3 balance or maintenance charge the maximum voltage of the battery is needed only when charging the battery at the fullest level. Current in that...
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Special characteristics affecting the selection vacon • 15 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 3 figure 14. The need of a balance charger a balance charger is basically the same as a bulk power device (grid converter or dc/dc converter) but with a smaller rating to be able...
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3 vacon • 16 special characteristics affecting the tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 15. Typical system layers energy management system (ems) power management system (pms) power conversion system power conversion hardware power conversion control (pcc) battery management system...
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Choosing a correct topology vacon • 17 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 4 4. Choosing a correct topology figure 16. Selection diagram dc/dc converter dc/dc converter connection to ac or dc direct to dc application control ref p / udc /idc customer primary reference cust...
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4 vacon • 18 choosing a correct topology tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 4.1 allowed topology configurations in the following table, example of allowed and not allowed configurations are given. These configurations are valid for both with dc/dc converter or with a direct battery con...
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Choosing a correct topology vacon • 19 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 4 not ok separate dc sources create different output voltage pattern which creates circulating current not ok if grid selectivity is needed, specially for ugrid not ok if grid selectivity is needed,...
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5 vacon • 19 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 5. Basic variants 5.1 direct to dc figure 18. Direct to dc 230 v unit 500 v unit 690 v unit vac supply voltage max 240 500 690 vac supply voltage min 208 380 vac over voltage instantly 437 911 1200 vdc over voltage u2t trip...
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Basic variants vacon • 20 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 5.1.1 control structure the power control is as presented below when the battery is directly on dc-link. Figure 19. Dc-link power control direct to dc can be used on a system where peak power shaving is desire...
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5 vacon • 21 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 • afe-operation mode o power control possible trough dc voltage reference. Needs controller if customer input is power reference (instead of dc voltage reference). O cannot make or maintain grid by itself, needs existing gr...
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Basic variants vacon • 22 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 5.2 dc to dc figure 21. Dc to dc 5.2.1 filter the filter topologies in focus are: 1. Interleaved figure 22. Interleaved filter topology # reference # reference a maximum full battery u battery voltage for fixe...
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5 vacon • 23 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 2. Independent output control (not yet supported) figure 23. Independent output control interleaving is a method to cancel partially or completely certain harmonics from the spectrum. With a standard 3-phase inverter unit, ...
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Basic variants vacon • 24 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 figure 25. Example simulation with traditional control and d=1/2: leg currents and sum current. I = 100a/leg, l= 2050 uh, udc = 1025v the ripple current for the filter choke can be calculated as follows: it is...
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5 vacon • 25 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 the maximum value for the ripple of the choke is obtained when d = 1/2 for the output current ripple there are three segments. When d low state and one switch is either low or high. When 1/3 one is either low or high. And w...
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Basic variants vacon • 26 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 figure 26. Peak-to-peak ripple current as function of duty cycle. Scaled values can be converted to real values by multiplying udc/(fsw*l) interleaved switching helps to reduce the output ripple, but does not ...
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5 vacon • 27 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 in most cases, a duty cycle d = 0,5 should be used in calculations. This will guarantee that worst case ripple is taken into consideration. For example, if the application operates with duty cycles 0.7-0.9, it could be poss...
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Basic variants vacon • 28 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 figure 28. Inductance as function of current (relative values). The typical tolerance for inductance is ±10%. Also smaller tolerance can be achieved, if needed. In the dc/dc converter, inductance tolerance doe...
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5 vacon • 29 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 29. Example simulation with interleaved control and d = 1/2: leg currents and sum current. I = 100 a/leg, l = 2050 uh, udc = 1025v. Leg u has 20% less inductance. Curve info rms max min peak to peak i 1 100.4 116.0 8...
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Basic variants vacon • 30 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 figure 30. Example simulation with interleaved control and d = 1/2: leg currents and sum current. I = 100 a/leg, l = 2050 uh, udc = 1025v. Leg u has 20% less and leg w 20% more inductance. Curve info rms max m...
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5 vacon • 31 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 the filter consists of three separate chokes, one for each leg (figure 31). It is not possible to use a traditional 3-phase choke because the current is dc (common mode) and the magnetic flux does not have a natural return ...
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Basic variants vacon • 32 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 figure 33. Lcl-filter structure is best possible solution if output ripple is critical. The optional capacitor forms an lcl-circuit with the cables and the battery. It is important to know the cable/battery im...
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5 vacon • 33 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 this will give some idea what could be expected to work, but because the battery properties are not taken into account in the design, it is not possible to guarantee a safe operation. If the filter does not operate as expec...
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Basic variants vacon • 34 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 5 5.2.2 control structure the figure below presents power control when the dc/dc converter is between dc-link and the battery. Figure 34. Power control example dc to dc can be used on a system where peak power s...
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5 vacon • 35 basic variants tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 • charging can be achieved by upper system control or simply by value id control functions. Charging will start automatically when the dc/dc converter overvoltage limit is reached even without charging reference. • when the...
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Product configuration examples vacon • 36 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 6 6. Product configuration examples 6.1 scope of delivery vacon delivers energy storage related power conversion equipment. The dc/dc converter includes power conversion hardware and power conver...
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6 vacon • 37 product configuration examples tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 the line measurement board d7 is instructed to be included in the delivery. Figure 38. Scope of delivery in tailored customer projects, the scope of delivery may be a switchgear including power modules, lcls...
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Product configuration examples vacon • 38 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 6 figure 40. Scope of delivery in tailored customer projects, the scope of delivery may be a switchgear including power modules, chokes, nxp controls with an application and a license but also br...
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6 vacon • 39 product configuration examples tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 6.2 example configurations 6.2.1 dc/dc for supply interruptions the dc/dc converter can be used to prevent grid voltage drops to interrupt essential drives to stop for undervoltage. The dc/dc converter is co...
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Product configuration examples vacon • 40 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 6 6.2.2 direct dc for grid support in case the battery voltage window is favorable, the batteries can be connected directly into the dc. The same usage case of power balancing of the grid also ap...
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7 vacon • 41 sizing of the system and product tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 7. Sizing of the system and product the basic principles that have an effect on the power unit selection are described in this chapter. 7.1 direct to dc the energy storage voltage window sets up the guidel...
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Sizing of the system and product vacon • 42 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 7 7.2 dc/dc the current capability of the dc/dc converter is limited by two constraints. The first constraint is the current rating defined in the rating plate of the power converter that defin...
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7 vacon • 43 sizing of the system and product tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 figure 46. Current capability of a dc/dc converter note! I nom = i 1 ~1.2*i 2 an example curve in above shows the combined current limit line for the dc/dc converter depending on the ratio of storage volta...
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Sizing of the system and p roduct vacon • 44 2 4 -hour suppo rt +358 (0)2 01 2 12 57 5 • email: se rvic e@vaco n.C o m 7 table 5. Dc/dc converter current ratings for nx6 air cooled nx6 drives 1025 vdc link voltage 1100 vdc 1025 vdc 931 vdc i nom i 1min i max i max i max unit type frame i dc nomi- na...
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7 vacon • 4 5 sizing of the system a nd pr oduct te l. + 358 (0) 20 1 21 21 • fax +358 (0 )2 01 21 2 285 air cooled nx6 drives 1025 vdc link voltage 1100 vdc 1025 vdc 931 vdc i nom i 1min i max i max i max unit type frame i dc nomi- nal (a) p dc nom (kw) i 1min 5khz (a) i 1min 3.6khz (a) i out 5khz ...
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Sizing of the system and product vacon • 46 24-hour support +358 (0)201 212 575 • email: service@vacon.Com 7 a dedicated tool is available to help in the selection of a correct power unit based on either power or current profile. Examples of dimensioning based on storage power and current profiles a...
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8 vacon • 47 information to acquire from customers tel. +358 (0) 201 2121 • fax +358 (0)201 212 285 8. Information to acquire from customers it is important to find enablers and limiting factors of the customer system. The following list is, in priority order, the information to be acquired from cus...
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Document id: dpd01887a rev. A vacon ltd member of the danfoss group runsorintie 7 65380 vaasa finland www.Danfoss.Com.