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| {{Menu_Photovoltaic_installations}} | | {{Menu_Photovoltaic_installations}}__TOC__ |
| __TOC__ | |
| | |
| == Grid connected PV system ≤ 10kW (Residential) == | | == Grid connected PV system ≤ 10kW (Residential) == |
|
| |
|
| === One single phase inverter === | | === One single phase inverter === |
|
| |
|
| *Typically, a 5kW grid-connected single-phase inverter. with UOC MAX ≤ 600V. | | * Typically, a 5kW grid-connected single-phase inverter. with UOC MAX ≤ 600V. One or two strings – Isctc < 25A, IAC < 32A. In this design there is no string protection. |
| *One or two strings – Isctc < 25A, IAC < 32A.
| | * A PV main switch is necessary. When the inverter is indoors, an additional remote controlled switch at the DC cable entry point is recommended for emergencies services. |
| *In this design there is no string protection.
| |
| *A PV main switch is necessary. When the inverter is indoors, an additional remote controlled switch at the DC cable entry point is recommended for emergencies services. | |
| | |
| [[File:Fig P22.png|none]]
| |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="180px" | Needs
| |
| ! align="center" width="110px" | String junction box
| |
| ! align="center" width="180px" | PV array main switch
| |
| ! align="center" width="160px" | Inverter
| |
| ! align="center" width="170px" | AC box (400V)
| |
| |- {{PV_HC1}} align="center"
| |
| | colspan="5" | '''Switchgears and control (Q)'''
| |
| |- {{PV_HC1}} align="center"
| |
| | - Isolation || • || • (d) || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Switching<br>(Making & breaking<br>rated current || •<br>DC21B || • (d)<br>DC21B || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Control || • (b) || • (d) || (e) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Over-current protection || (c) || || || • (f)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Protection against<br>Insulation fault || || || (g) || (g) <br>RCD type B or A SI
| |
| |- {{PV_HC2}} align="center"
| |
| | '''Surge protection (SPD)''' || || • type 2 || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor<br>Double insulation || Indoor<br>Double insulation || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || Inverter relevant parameters || Energy
| |
| |}
| |
| (a) PV array main switch could be included in the inverter. This solution makes inverter service or replacement more difficult.<br>
| |
| (b) Remote switching for emergency services located as closely as possible to the PV modules or to the point of entry of DC cables in the building.<br>
| |
| (c) No protection is required when the number of string does not exceed 2.<br>
| |
| (d) Service and emergency switching<br>
| |
| (e) Inverter shall include a protection for anti-islanding (in accordance with VDE 0126 for example)<br>
| |
| (f) Overload and short-circuit protection B curve recommended.<br>
| |
| (g) If the inverter provides no galvanic separation a RCD protection is necessary on AC side. IEC 60364-712 specifies RCD type B. Some local regulations require RCD type A SI<br>
| |
| | |
| '''''Fig. P22 :''''' ''Grid connected ≤ 10kW''
| |
| | |
| == 10 to 100kW grid connected PV system (Small building)==
| |
| | |
| === One three phase multi input inverter without array box ===
| |
| | |
| * Typically, 10kW to 36kW grid-connected inverters, U<sub>OC MAX</sub> probably higher than 600V (i.e. 800V or 1000V), Isctc < 125A, Iac < 63A.
| |
| * In this range of power, inverters usually have between 2 and 4 maximum power point tracking (MPPT) inputs, so the number of strings in the same DC sub-network is equal to one or two.
| |
| * There is no need for string protection.
| |
| * A PV main switch for each MPPT input is necessary.
| |
| * When an inverter is indoors, additional remote-controlled switches at DC cable entry point are recommended for emergencies services.
| |
|
| |
|
| [[File:Fig P23.png|none]]
| | {{FigImage|DB422723_EN|svg|P22|Grid connected <{{=}} 10kW}} |
|
| |
|
| {| class="wikitable" width="800px"
| | == 10 to 100kW grid connected PV system (Small building) == |
| |-
| |
| ! width="170px" | Needs
| |
| ! align="center" width="145px" | String junction box
| |
| ! align="center" width="165px" | PV array main switch
| |
| ! align="center" width="135px" | Inverter
| |
| ! align="center" width="185px" | AC box (400V)
| |
| |- {{PV_HC1}} align="center"
| |
| | colspan="5" | '''Switchgears and control (Q)'''
| |
| |- {{PV_HC1}} align="center"
| |
| | - Isolation || • || • (d) || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Switching<br>(Making & breaking<br>rated current || •<br>DC21B || • (d)<br>DC21B || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Control || • (b) || • (d) || (e) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Over-current protection || (c) || || || • (f)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Protection against<br>Insulation fault || || || (h) || (h)<br>RCD type B or A SI
| |
| |- {{PV_HC2}} align="center"
| |
| | '''Surge protection (SPD)''' || (g) || • type 2 || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor IP5x<br>Double insulation || Indoor IP5x<br>Double insulation || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || || Energy
| |
| |}
| |
| (a) PV array main switch could be included in the inverter. This solution makes inverter service or replacement difficult.<br>
| |
| (b) Remote switching for emergency services located as closely as possible to the PV modules or to the point of entry of DC cables in the building.<br>
| |
| (c) No protection is required when the number of string does not exceed 2.<br>
| |
| (d) Service and emergency switching<br>
| |
| (e) Inverter shall include a protection for anti-islanding (in accordance with VDE 0126 for example)<br>
| |
| (f) Overload and short-circuit protection (B curve recommended).<br>
| |
| (g) If there is no SPD in the inverter or if the distance between String junction box and inverter exceeds 10m a SPD is necessary in this box.<br>
| |
| (h)
| |
| *If the inverter provides no galvanic separation a RCD protection is necessary on AC side. IEC 60364-712 specifies RCD type B. Some local regulations require RCD type A SI
| |
| *If the inverter provides at least simple separation
| |
| ** Without functional earthing: insulation monitoring is necessary, it's usually done by the inverter in this range of power.
| |
| ** With functional earthing: the earthing shall be done with a DC MCB breaker (C60PV 4P series 2 – 10A) or a fuse.
| |
|
| |
|
| '''''Fig. P23 :''''' ''10-100kW single multi MPPT inverter''
| | === One three phase inverter with one string combiner box === |
| | |
| | |
| === One three phase inverter with One Array box === | |
|
| |
|
| * Typically, 30kW to 60kW grid-connected inverters. U<sub>OC max</sub> is generally higher than 600V (up to 1000V), Isctc does not exceed 200A, Iac does not exceed 100A. | | * Typically, 30kW to 60kW grid-connected inverters. U<sub>OC max</sub> is generally higher than 600V (up to 1000V), Isctc does not exceed 200A, Iac does not exceed 100A. |
| Line 110: |
Line 18: |
| * A main PV switch is required. When an inverter is inside, additional remote-controlled switch at DC cable entry point is recommended for emergencies. | | * A main PV switch is required. When an inverter is inside, additional remote-controlled switch at DC cable entry point is recommended for emergencies. |
|
| |
|
| [[File:Fig P24.png|none]]
| | {{FigImage|DB422725_EN|svg|P23|10-100kW single MPPT inverter}} |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="160px" | Needs
| |
| ! align="center" width="135px" | String / Array junction box
| |
| ! align="center" width="160px" | PV array main switch
| |
| ! align="center" width="145px" | Inverter
| |
| ! align="center" width="200px" | AC box (400V)
| |
| |- {{PV_HC1}} align="center"
| |
| | colspan="5" | '''Switchgears and control (Q)'''
| |
| |- {{PV_HC1}} align="center"
| |
| | - Isolation || • || • (d) || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Switching<br>(Making & breaking<br>rated current || •<br>DC21B || • (d)<br>DC21B || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Control || • (b) || • (d) || (e) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Over-current protection || • || (c) || || • (f) | |
| |- {{PV_HC1}} align="center"
| |
| | - Protection against<br>Insulation fault || || || (h) || (h)<br>RCD type B or A SI
| |
| |- {{PV_HC2}} align="center"
| |
| | '''Surge protection (SPD)''' || (g) || • type 2 || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor IP5x<br>Double insulation || Indoor IP5x<br>Double insulation || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || || P, Q, PF, Energy
| |
| |}
| |
| (a) PV array main switch could be included in the inverter. This solution makes inverter service or replacement difficult.<br>
| |
| (b) Remote switching for emergency services located as closely as possible to the PV modules or to the point of entry of DC cables in the building. The main switch in array box can be equipped with tripping coil and motor mechanism for remote reclosing for that purpose.<br>
| |
| (d) Service and emergency switching<br>
| |
| (e) Inverter shall include a protection for anti-islanding (in accordance with VDE 0126 for example)<br>
| |
| (f) Overload and short-circuit protection (B curve recommended).<br>
| |
| (g) If there is no SPD in the inverter or if the distance between String / Array junction box and inverter exceeds 10m a SPD is necessary in this box.<br>
| |
| (h)
| |
| * If the inverter provides no galvanic separation a RCD protection is necessary on AC side. IEC 60364-712 specifies RCD type B. Some local regulations require RCD type A SI.
| |
| * If the inverter provides at least simple separation
| |
| ** Without functional earthing: insulation monitoring is necessary
| |
| ** With functional earthing: the earthing shall be done with a DC MCB breaker (C60PV 4P series 2 – 10A) or a fuse.
| |
| | |
| '''''Fig. P24 :''''' ''10-100kW single MPPT inverter''
| |
| | |
|
| |
|
| === Multi single phase inverters design === | | === Multi single phase inverters design === |
| Line 159: |
Line 26: |
| * In that case, the DC system is very simple and the AC system is very similar to usual AC systems. | | * In that case, the DC system is very simple and the AC system is very similar to usual AC systems. |
|
| |
|
| [[File:Fig P25.png|none]]
| | {{FigImage|DB422726_EN|svg|P24|10-100kW multi single MPPT inverter}} |
| | |
| {| class="wikitable" width="800px" | |
| |-
| |
| ! width="170px" | Needs
| |
| ! align="center" width="120px" | PV array<br>main switch
| |
| ! align="center" width="140px" | Inverter
| |
| ! align="center" width="180px" |
| |
| ! align="center" width="190px" | AC box (400V)
| |
| |- {{PV_HC1}} align="center"
| |
| | '''Switchgears and control (Q)''' || colspan="4" | See ≤10kW design | |
| |- {{PV_HC1}} align="center"
| |
| | '''Surge protection (SPD)''' || • type 2 || || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor IP5x<br>Double insulation || || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || Energy || P,Q, PF, Energy, unbalance
| |
| |}
| |
| (h) If the inverter provides no galvanic separation a RCD protection is necessary on AC side. IEC 60364-712 specifies RCD type B. Some local regulations require RCD type A SI<br>
| |
| '''''Fig. P25 :''''' ''10-100kW multi single MPPT inverter''
| |
| | |
| | |
| === Three phase inverter with two Array boxes (Na ≤ 2) ===
| |
| | |
| Typically, 60kW to 100kW grid-connected inverters with 2 arrays. Array cable protection is not necessary for 2 or 3 arrays.
| |
| The I<sub>sctc</sub> array ≤ 200A, I<sub>sctc</sub> ≤ 400A, and I<sub>max</sub> AC ≤ 200A. A PV main switch is required close to the inverter. Remotely operated switches in array boxes allow disconnects to be located close to the PV modules in the event of emergencies.
| |
| | |
| [[File:Fig P26.png|none]]
| |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="160px" | Needs
| |
| ! align="center" width="135px" | String / Array junction box
| |
| ! align="center" width="170px" | PV array main switch
| |
| ! align="center" width="160px" | Inverter
| |
| ! align="center" width="175px" | AC box (400V)
| |
| |- {{PV_HC1}} align="center"
| |
| | colspan="5" | '''Switchgears and control (Q)'''
| |
| |- {{PV_HC1}} align="center"
| |
| | - Isolation || • || • (d) || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Switching<br>(Making & breaking<br>rated current || •<br>DC21B || • (d)<br>DC21B || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Control || • (b) || • (d) || (e) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Over-current protection || • || (c) || || • (f)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Protection against<br>Insulation fault || || || (h) || (h)<br>RCD type B or A SI
| |
| |- {{PV_HC2}} align="center"
| |
| | '''Surge protection (SPD)''' || (g) || • type 2 || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor IP5x<br>Double insulation || Indoor IP5x<br>Double insulation || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || || P, Q, PF, Energy
| |
| |}
| |
| (a) PV array main switch could be included in the inverter. This solution makes inverter service or replacement difficult.<br>
| |
| (b) If switching for emergency services is required, the main switch in array box can be equipped with tripping coil and motor mechanism for remote reclosing.<br>
| |
| (c) No protection is required when the number of arrays ≤ 3 (No cable sizing benefit)<br>
| |
| (d) Service and emergency switching<br>
| |
| (e) Inverter shall include a protection for anti-islanding (in accordance with VDE 0126 for example)<br>
| |
| (f) Overload and short-circuit protection.<br>
| |
| (g) If there is no SPD in the inverter or if the distance between DC box and inverter exceeds 10m a SPD is necessary in this box.<br>
| |
| (h)
| |
| * If the inverter provides no galvanic separation a RCD protection is necessary on AC side. IEC 60364-712 specifies RCD type B. Some local regulations require RCD type A SI
| |
| * If the inverter provides at least simple separation
| |
| ** Without functional earthing: insulation monitoring is necessary
| |
| ** With functional earthing: the earthing shall be done with a DC MCB breaker (iC60PV 4P series 2 – 10A) or a fuse.
| |
| | |
| '''''Fig. P26 :''''' ''10-100kW single MPPT inverter with 2 arrays''
| |
|
| |
|
| == 150kW to 500kW Grid connected PV system (Large building and farm) == | | == 150kW to 500kW Grid connected PV system (Large building and farm) == |
|
| |
|
| === Three phase inverter with more than two Array boxes === | | === Three phase inverter with more than two string combiner boxes === |
|
| |
|
| * Typically, 150kW to 500kW single inverter. | | * Typically, 150kW to 500kW single inverter. |
| * This design is very similar to the previous one except that it has more arrays, which requires array cable protection. | | * This design is very similar to the three phase inverter with one string combiner box except that it has more arrays, which requires array cable protection. |
| * Istc <= 400A, IAC <= 600A. | | * Istc <= 400A, IAC <= 600A. |
|
| |
|
| [[File:Fig_P27_2015.jpg|none]]
| | {{FigImage|DB422728_EN|svg|P25|150-500kW single MPPT inverter with N arrays > 2}} |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="150px" | Needs
| |
| ! align="center" width="70px" | String
| |
| ! align="center" width="130px" | Array junction box
| |
| ! align="center" width="140px" | Generator junction box
| |
| ! align="center" width="140px" | Inverter
| |
| ! align="center" width="170px" | AC box 400V or other voltage (Transfoless inverter)
| |
| |- {{PV_HC1}} align="center"
| |
| | colspan="6" | '''Switchgears and control (Q)'''
| |
| |- {{PV_HC1}} align="center"
| |
| | - Isolation || • || • || • || (a) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Switching<br>(Making & breaking<br>rated current || || •<br>DC22A || • <br>DC22A || • (a) || • (d) | |
| |- {{PV_HC1}} align="center"
| |
| | - Control || || • (b) || || • (a)(e) || • (d)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Over-current protection || • || || • (c) || || • (f)
| |
| |- {{PV_HC1}} align="center"
| |
| | - Protection against<br>Insulation fault || || || || • (h) || • (h)
| |
| |- {{PV_HC2}} align="center"
| |
| | '''Surge protection (SPD)''' || || (g) || • type 2 || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || || Outdoor IP5x<br>Double insulation || Indoor<br>Double insulation || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || || || P, Q, PF, Energy, Alarm, THD, individual harmonics
| |
| |}
| |
| (a) PV array main switch could be included in the inverter. This solution makes inverter service or replacement more difficult.<br>
| |
| (b) If switching for emergency services is required, the main switch in array box can be equipped with tripping coil and motor mechanism for remote reclosing.<br>
| |
| (c) Array cable protection is recommended to prevent cable oversizing. To ensure fast trip of protections 6 to 8 arrays are recommended.<br>
| |
| (d) Service and emergency switching <br>
| |
| (e) Inverter shall include a protection for anti-islanding (in accordance with VDE 0126 for example)<br>
| |
| (f) Overload and short-circuit protection.<br>
| |
| (g) If there is no SPD in the inverter or if the distance between DC box and inverter exceeds 10m a SPD is necessary in this box.<br>
| |
| (h) Galvanic insulation is provided by LV/MV transformer,<br>
| |
| :* PV system without functional earthing: insulation monitoring is necessary: IMD - IM20 and accessory IMD-IM20-1700
| |
| :* PV system with functional earthing: the earthing shall be done with a DC MCB breaker (C60PV 4P series 2 – 10A) or a fuse.
| |
| '''''Fig. P27 :''''' ''150-500kW single MPPT inverter with N arrays > 2''
| |
| | |
| === Multi single phase inverters design ===
| |
| | |
| Typically 10x20 to 20x30kW grid connected inverters <br>
| |
| U<sub>oc</sub> max ≤ 1000V one or two string per inverter. IAC max 50A for one inverter.
| |
| | |
| [[File:Fig P28.png|none|800px]]
| |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="200px" | Needs
| |
| ! align="center" width="150px" | String junction box
| |
| ! align="center" width="130px" |
| |
| ! align="center" width="130px" |
| |
| ! align="center" width="190px" | AC Combiner box
| |
| |- {{PV_HC1}} align="center"
| |
| | '''Switchgears and control (Q)''' || See 10 to 36kW design || || ||
| |
| |- {{PV_HC1}} align="center"
| |
| | '''Surge protection (SPD)''' ||• type 2 || || || • type 1 or 2
| |
| |- {{PV_HC3}} align="center"
| |
| | '''Enclosure (E)''' || Outdoor IP5x<br>Double insulation || || || Standard AC requirement +<br>grid code requirement
| |
| |- {{PV_HC4}} align="center"
| |
| | '''Metering''' || || || Energy || P, Q, PF, Energy, Alarm
| |
| |}
| |
| '''''Fig. P28 :''''' ''150-500kW multi 3-phases inverters''
| |
| | |
| === Multi MW Grid connected PV system (Large building and farm)===
| |
| | |
| * Typically 500kW-630kW inverters with LV/MV transformers and MV substation.
| |
| | |
| [[File:Fig P29.png|none]]
| |
| | |
| {| class="wikitable" width="800px"
| |
| |-
| |
| ! width="150" | Needs
| |
| ! width="70" align="center" | String
| |
| ! width="130" align="center" | Array junction box
| |
| ! width="140" align="center" | Generator junction box
| |
| ! colspan="2" |Inverter
| |
| ! width="170" align="center" | AC box 400V or other voltage (Transfoless inverter)
| |
| |-
| |
| !
| |
| !
| |
| !
| |
| !
| |
| ! DC side
| |
| ! AC side
| |
| !
| |
| |- align="center"
| |
| | colspan="7" | '''Switchgears and control (Q)'''
| |
| |- align="center"
| |
| | - Isolation
| |
| | •
| |
| | •
| |
| | • (a)
| |
| |•
| |
| |•
| |
| | •
| |
| |- align="center"
| |
| | - Switching<br>
| |
| (Making & breaking<br>
| |
| rated current
| |
| |
| |
| | •<br>
| |
| DC22A
| |
| | • (a)
| |
| |•
| |
| DC22A or
| |
| 23A
| |
| |•
| |
| AC1
| |
| | •
| |
| |- align="center"
| |
| | - Control
| |
| |
| |
| | • (b)
| |
| |
| |
| |•
| |
| |•
| |
| | •
| |
| |- align="center"
| |
| | - Over-current protection
| |
| | •
| |
| |
| |
| | • (c)
| |
| |No
| |
| |•
| |
| | • (f)
| |
| |- align="center"
| |
| | - Protection against<br>
| |
| Insulation fault
| |
| |
| |
| |
| |
| |• (h)
| |
| |•
| |
| |
| |
| | • (h)
| |
| |- align="center"
| |
| | '''Surge protection (SPD)'''
| |
| |
| |
| | (g)
| |
| | • type 2
| |
| | colspan="2" |(g)
| |
| | • type 1 or 2
| |
| |- align="center"
| |
| | '''Enclosure (E)'''
| |
| |
| |
| | Outdoor IP5x<br>
| |
| Double insulation
| |
| | Indoor<br>
| |
| Double insulation
| |
| | colspan="2" |
| |
| |
| |
| |- align="center"
| |
| | '''Metering'''
| |
| |
| |
| | Energy
| |
| |
| |
| | colspan="2" |
| |
| | P, Q, PF, Energy, Alarm, Power quality
| |
| |}
| |
| (a) PV array main switch is usually included in the inverter panel.<br>
| |
| (b) If switching for emergency services is required, the main switch in array box can be equipped with tripping coil and motor mechanism for remote reclosing.<br>
| |
| (c) Array cable protection is recommended to prevent cable oversizing. To ensure fast trip of protections 6 to 8 arrays are recommended.<br>
| |
| (f) Overload and short-circuit protection.<br>
| |
| (g) If there is no SPD in the inverter or if the between DC box and inverter >10m a SPD is necessary in this box.<br>
| |
| (h) Galvanic insulation is provided by LV/MV transformer,
| |
| * PV system without functional earthing: insulation monitoring is necessary: IMD - IM20 and accessory IMD-IM20-1700
| |
| * PV system with functional earthing: the earthing shall be done with a DC MCB breaker (C60PV 4P series 2 – 10A) or a fuse.
| |
| '''''Fig. P29 :''''' ''500-630kW inverters with LV/MV transformers''
| |
