Application note. 0 % / 70 % feed-in regulation

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1 Application note 0 % / 70 % feed-in regulation

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3 Application note 0 % / 70 % feed-in regulation PV feed-in regulation depending on owner's electricity consumption Contents Precondition.... Balancing settlement procedure.... Selective settlement procedure...5 Purpose and scope of application... 6 General situation Current challenge...6. Solution for raising the feed-in limit % regulation...9 Connection options Grid connection variants Wiring diagram Wiring diagram... 6 Connecting measurement equipment/ meters Powador-proLOG on energy meter without S0 pulse interface Powador-proLOG on energy meter with S0 pulse interface Powador-proLOG on grid analysis device with ModBus interface Powador-piccoLOG on energy meter without S0 pulse Powador-piccoLOG on energy meter with S0 pulse Powador-piccoLOG on energy meter with RS85 KACO protocol Configuration on the data logger Powador-piccoLOG Powador-proLOG Glossary... Application note for 0 % / 70 % feed-in regulation Page

4 Precondition Precondition NOTE The solutions below for 0 % or 70 % regulation of a PV plant only work if the feed-in meter and accounting by the grid operator are accumulating. This means that each phase is not regulated/ accounted separately but all three phases are treated as a whole. If you do not receive an accumulating statement from the grid operator, you cannot implement this regulation.. Balancing settlement procedure MADE IN GERMANY XL 0kW L 5kW 5kW kw -kw,5kw L kw 5kW kw -kw kw 5 L N 5kW 5kW kw Σ= kw 5kW kw kw With balancing settlement Without balancing settlement Regulation 0 % / 70 % -kw,5kw 0kW 6 Figure : How the balancing settlement procedure works Key (numbers in Figure ) Consumption per phase Reduction through balancing settlement PV power per phase 5 Without balancing settlement Difference 6 0 W supplied In the balancing settlement procedure, three-phase/single-phase inverters with a data logger and a measuring device must be connected to the phases L, L and L. The network operator calculates the total amount of energy fed in and the total amount of energy supplied. The energy fed in is spread evenly across all three phases. If the network operator does not use a balancing settlement procedure, the selective settlement procedure is used. Page Application note for 0 % / 70 % feed-in regulation

5 Precondition. Selective settlement procedure MADE IN GERMANY XL L 5kW 5kW 0kW MADE IN GERMANY XL L kw 5kW kw MADE IN GERMANY XL L 5kW 5kW 0kW Figure : How the selective settlement procedure works Key (numbers in Figure ) Consumption per phase PV power per phase Measuring device/s0 meter In the selective settlement procedure, single-phase inverters with a data logger and feed-in meter must be connected to each phase. The network operator calculates the amount of energy fed in per phase and the total amount of energy supplied. The energy fed in is spread evenly across all three phases. Three-phase inverters therefore cannot be connected. For each phase, the lower consumption is communicated to the corresponding data logger via the feed-in meter. The data logger calculates the feed-in reduction and transmits this directly to the inverter. The inverter then adjusts its feed-in power to match consumption on this phase. NOTE In this implementation, the SymBus must be neither activated nor connected in the inverter. If activated incorrectly, a three-phase inverter is simulated by three single-phase inverters. Application note for 0 % / 70 % feed-in regulation Page 5

6 Purpose and scope of application Purpose and scope of application This document describes solutions that can be used to increase the energy generated by the owner's consumption of the photovoltaic with an existing feed-in regulation. It also documents how the feed-in is prevented into the power grid if required. General situation. Current challenge Photovoltaic systems whose total output does not exceed 0 kwp have the option in many European countries to store a fixed feed-in limit to avoid having to install an expensive ripple control receiver. In other countries however, the PV systems are permitted to be connected to the public grid, but not to feed into these networks. Due to these requirements from the grid operator, a solution needed to be developed for new systems and existing systems. Basically the 70 % regulation produces the following graphical display (Figure ) Power [kw] :00 0:00 0:00 06:00 08:00 0:00 :00 :00 6:00 8:00 0:00 :00 00:00 Time [hh:mm] Figure : Diagram of energy feed-in with lost energy >70%. Power [kw] :00 0:00 0:00 06:00 08:00 0:00 :00 :00 6:00 8:00 0:00 :00 00:00 Time [hh:mm] Figure : Diagram of increase in owner's consumption Key (numbers in Figure ) Key (numbers in Figure ) 70 % feed-in power (yellow area) 70 % feed-in power (yellow area) Lost feed-in power (red area) Available feed-in power with new software solution (green area) 70 % fixed feed-in limit (grey line) - regulation command to inverter (70 %) 70 % fixed feed-in limit (grey line) - regulation command to inverter (70 %) To make this form of regulation easier to understand, the function is used on a 0 kwp system. With a fixed regulation logic of 70 %, the maximum feed-in power is 7 kw. As shown in Figure, the power portion above this of approx. kw would be lost. The new software solution from KACO new energy permits the 0 % of the total output to be made available with an existing feed-in limit to 70 % in which the inverter power is regulated depending on the current consumption. Page 6 Application note for 0 % / 70 % feed-in regulation

7 General situation. Solution for raising the feed-in limit The new software solution allows the fixed feed-in limit of 70 % to be raised to 70 % + X, The X here represents the owner's consumption, for example in a detached house. For the feed-in limit to be raised above 70 %, an additional digital consumption meter must be connected to the data logger. The examples below explain how to connect a meter. The total consumption is communicated to the data logger by the additional meter so that the logger can establish a new maximum feed-in power. This maximum feed-in power is sent to the inverter via an active power command. If the feed-in power of a PV system is compared with the consumption of a detached home, a graph such as the following example is produced. 0 9 Power [kw] :00 0:00 0:00 06:00 08:00 0:00 :00 :00 6:00 8:00 0:00 :00 00:00 Time [hh:mm] Figure 5: Diagram comparing the energy requirement of a detached home and PV output Key (numbers in Figure 5) Energy requirement of a detached home 70 % feed-in power (yellow area) 70 % fixed feed-in limit (grey) - regulation command to inverter (70%) Lost feed-in power (red area) The graphic shows that a continuous base load is present primarily at night. It also shows that apart from the base load, there is always an on and off of the consumer which can be produced by connecting and disconnecting a TV, oven, iron, computer, light, etc. (Pos. ) Based on this graph, we can see that the actual consumption values communicated would result in considerably less power being lost from the PV system. Application note for 0 % / 70 % feed-in regulation Page 7

8 General situation Power [kw] 6 5 Regulation command to inverter 0 00:00 0:00 0:00 06:00 08:00 0:00 :00 :00 6:00 8:00 0:00 :00 00:00 Time [hh:mm] Figure 6: Diagram of increase in owner's consumption Key (numbers in Figure 6) Regulation command to inverter 70 % + owner's consumption PV power gained through owner's consumption 70 % feed-in power PV power lost despite owner's consumption Using the data logger for calculations allows more efficient use to be made of the PV system so that more energy can be produced and then used in the owner's home. Graph (Figure 6) also shows that a red area (lost energy) is nevertheless produced because the amount of power consumed by the owner has fallen to 0 but the PV system could provide more electricity. When the intrinsic consumption falls to 0 kw, the 70 % regulation function takes effect again. Page 8 Application note for 0 % / 70 % feed-in regulation

9 General situation. 0 % regulation In countries where feed-in into the public grid is not desirable or is prohibited, the regulation must ensure that no power is fed from the system into the public grid. Depending on the intrinsic consumption, the PV system output may be connected up so that the user can make use of the energy generated himself and nothing has to be purchased from the public grid. The consumption meter must therefore be connected to the data logger so that the logger can generate the regulation commands. If a consumption meter is not connected to the data logger, the logger continuously sends a regulation command to the inverters with a 0 % feed-in maximum. This means that feed-in must not take place. The graph below shows the possible PV power (red) and the power actually used in the home (green). 0 9 Power [kw] :00 0:00 0:00 06:00 08:00 0:00 :00 :00 6:00 8:00 0:00 :00 00:00 Time [hh:mm] Figure 7: Diagram of 0% regulation Key (numbers in Figure 7) PV power available (red area) Bought-in power (yellow area) Energy requirement of a detached home (green area) By connecting up additional consumers, heating, water or energy storage systems (e.g. Powador-gridsave), owner's consumption and therefore use of the PV current can be increased considerably. This function can however only be used by Powador-proLOG because this has an S0 output and could therefore connect up another consumer via a relay circuit. Alternatively, depending on the system fitted, this connection for another consumer could also take on the internal "Priwatt" function of the inverter. Application note for 0 % / 70 % feed-in regulation Page 9

10 Connection options Connection options PV generator Inverter inverters inverters < 0kWp Powador-proLOG XL Powador-piccoLOG Measurement unit from MSE Janitza S0 from digital meter S0 from optical meter reader Measurement equipment S0 from digital meter S0 from optical meter reader Properties Communication via: Modbus TCP Communication via: S0 Communication via: RS85 Communication via: S0 Figure 8: Overview of connection options 5 Grid connection variants The diagram below shows what the connections for the entire PV system could look like in principle. It shows the PV system, the fitted meters and the consumers which exist in every home. Depending on irradiance, the amount of power produced by the system will vary. The arrows show what the home buys in (red line) and the system output (green line). The pale blue line shows the commands sent to the PV system (inverters). To produce these commands, the data logger needs details from the meter to allow it to determine the current feed-in power and/or energy requirement (dark blue line). The difference that is actually fed into the public grid is calculated from these values. Page 0 Application note for 0 % / 70 % feed-in regulation

11 Zweirichtungszähler Grid connection variants 5. Wiring diagram High irradiance Photovoltaic array Medium irradiance Low irradiance MADE IN GERMANY XL Figure 9: Wiring diagram Key Inverter 5 Digital feed-in meter / reference meter Consumer 6 Regulation command to inverter Powador-proLOG XL / piccolog data logger 7 Data line from consumption meter Digital consumption meter / single-direction meter 8 Public grid This wiring diagram shows two meters (feed-in meter / bought-in electricity meter & consumption meter) in the PV system. The consumption meter may only measure the consumers in the home. The PV system must not be included in the measurement. Balancing/non-balancing meters with and without a return inhibit can be used for the consumption meter because the energy direction is always the same in all phases. As in all the examples which follow, the data logger must be connected to the inverter via the RS85 interface. Application note for 0 % / 70 % feed-in regulation Page

12 Zweirichtungszähler Grid connection variants 5. Wiring diagram MADE IN GERMANY XL Figure 0: Wiring diagram Key Inverter 5 Digital feed-in meter / bidirectional meter Consumer 6 Regulation command to inverter Powador-proLOG XL / piccolog data logger 7 Data line Digital balancing feed-in meter with return inhibit or grid analysis device 8 Public grid In the second wiring diagram, two meters are fitted in a PV system. Alongside the grid operator's bidirectional meter, another meter which also measures feed-in (and bought-in electricity) must also be installed. In the simplest variant, a balancing single-direction meter with return inhibit is fitted and measures the feed-in. Alternatively with prolog, a balancing bidirectional meter with return inhibit can also be connected to record the bought-in electricity at the same time. A grid analysis device can also be used for the same function with prolog. Page Application note for 0 % / 70 % feed-in regulation

13 Connecting measurement equipment/meters 6 Connecting measurement equipment/meters 6. Powador-proLOG on energy meter without S0 pulse interface In the example below, the Powador-proLOG XL data logger is connected to the energy meter with an optical meter reader. NOTE Only Powador-proLOGs from the XL series can activate this example in the software. + - DI MADE IN GERMANY XL V + - Figure : Powador-proLOG on energy meter without S0 pulse interface Key Powador-proLOG XL S0 pulse (white) Analogue energy meter with optical meter Cable for optical meter reader reader The optical meter reader records the rotating aluminium disc of an analogue meter and the pulsating LED of a digital meter without S0 interface and supplies the data logger with a certain pulse rate. For the data logger to understand how many pulses represent one kwh, this pulse constant must be stored in the data logger. Before you can store the pulse constant, the digital input must be activated. Instructions for setting / activating the digital inputs can be found in the data logger's manual. In this example, the positive cable from the optical meter reader simply has to be connected to the data logger because the negative connections are made inside the data logger. If the optical meter reader is powered by an external power supply unit, the negative connection of the external power source must be connected with the negative connection on the DI input. Application note for 0 % / 70 % feed-in regulation Page

14 Connecting measurement equipment/meters 6. Powador-proLOG on energy meter with S0 pulse interface In the example below, the Powador-proLOG XL data logger is connected to the consumption meter with an integrated S0 pulse output. NOTE Only Powador-proLOGs from the XL series can activate this example in the software. + - DI MADE IN GERMANY XL Figure : Powador-proLOG on energy meter with S0 pulse interface Key Powador-proLOG XL S0 pulse Digital energy meter with S0 output A digital consumption meter, which can communicate the precise consumption, is connected to the Powador-proLOG. Unlike the previous example, no additional hardware is needed here. If the feed-in meter is connected correctly to the data logger's DI input, the DI input must be activated and the pulse constant of the counter stored in the Powador-proLOG. As explained in this example, the consumption meter is connected directly to the data logger (Powador-proLOG XL). To increase consumption, the data logger can use a digital output to switch a relay, which can activate other consumers. Page Application note for 0 % / 70 % feed-in regulation

15 Connecting measurement equipment/meters 6. Powador-proLOG on grid analysis device with ModBus interface In the following example, a Powador-proLOG data logger of the XL series is connected to a grid analysis device from Janitza with a switch. MADE IN GERMANY XL Figure : Powador-proLOG on grid analysis device with ModBus TCP (Ethernet) interface Key Powador-proLOG XL Janitza grid analysis device Hub Ethernet cable Because the software function is not only used in small systems, an example with large systems is provided too. The Janitza grid analysis device determines the consumption of say a factory building or shopping centre and transmits this value directly via ModBus TCP to the data logger which in turn can generate the active power commands to send these to the inverters. The Janitza grid analysis device is already stored in the data logger's database and can therefore be used right away. For the data logger to know that there is a component communicating using ModBus in the network, it must be stored in the prolog using the IP address. Application note for 0 % / 70 % feed-in regulation Page 5

16 Connecting measurement equipment/meters 6. Powador-piccoLOG on energy meter without S0 pulse In this example, a Powador-piccoLOG and an optical meter reader which contains an analogue consumption meter are used. + DI - RS V Figure : Powador-piccoLOG and energy meter without S0 pulse Key Powador-piccoLOG External voltage supply for optical meter reader Analogue or digital energy meter with optical meter reader without S0 pulse Cable for optical meter reader with potential equalisation The optical meter reader usually delivers 000 pulses per kwh to the data logger. The pulse rate in the Powador-piccoLOG can of course be adapted. The number of kwh per disc revolution or number of LEDs, which must be applied in the data logger, is stated on the type plates of the meters. 6.5 Powador-piccoLOG on energy meter with S0 pulse In this example, a Powador-piccoLOG is connected to a meter which has its own S0 output. + - DI RS85 Figure 5: Powador-piccoLOG on energy meter with S0 pulse Key Powador-piccoLOG Digital energy meter with S0 output You need to route two wires from the meter to the data logger, and connect up the data logger accordingly. Because there is a difference between the consumption and feed-in meters, you should read the quick guide and/or manual for the Powador-piccoLOG. This describes how a meter needs to be connected. Again in this case the pulse constant must be reported to the data logger so that precise regulation can take place. For this, you have to enter the correct pulse constant in the device management tool and transfer it to the data logger. More information can be found in Chapter 6. Page 6 Application note for 0 % / 70 % feed-in regulation

17 Connecting measurement equipment/meters 6.6 Powador-piccoLOG on energy meter with RS85 KACO protocol In this example, a Powador-piccoLOG is connected with the measurement equipment which communicates the measured value via RS85. RS85 Figure 6: Powador-piccoLOG on the measurement equipment Key Powador-piccoLOG Measurement equipment (RS85 KACO protocol) This measurement equipment is connected to the RS85 interface, as is an inverter. This solution has the shortest response time. KACO new energy therefore recommends using the measurement equipment if possible. Connecting the KACO measuring point to our data loggers reduces the number of inverters that can be connected by. piccolog >> - = Application note for 0 % / 70 % feed-in regulation Page 7

18 Configuration on the data logger 7 Configuration on the data logger 7. Powador-piccoLOG Figure 7: Device management tool for Powador-piccoLOG Connecting data logger KACODMT software tool installed on the PC.. Connect data logger to PC using micro USB cable.. Start device management tool (KACODMT).. Select piccolog manager. Page 8 Application note for 0 % / 70 % feed-in regulation

19 Configuration on the data logger Figure 8: Power control settings. Select "Power control" button on left. 5. Select "No ripple control receiver". 6. Select the "Maximum grid feed-in" in the drop-down box. 7. Activate "Take owner's energy consumption into account". 8. Hit "Transfer" button to send configuration to the data logger.»» Configuration completed with success. Application note for 0 % / 70 % feed-in regulation Page 9

20 Configuration on the data logger 7. Powador-proLOG Figure 9: Configuration using Powador-proLOG software Connect data logger with PC and have data logger start page open.. Configure grid analysis device, feed-in meter or consumption meter as usual. (See operating instructions for Powador-proLOG (Chapter 0). Admin measurement >> Power control >> Select general configuration, the active power process "P Fix" (See Figure 9). Figure 0: P Fix settings. Click on the "Configure" button, after selecting the active power process.. Enter the desired reduction (see Figure 0), in our example, this is an inverter limitation to 70% 5. Now only IPL needs to be activated. This is done by selecting "Yes" in the drop-down box Page 0 Application note for 0 % / 70 % feed-in regulation

21 Glossary 8 Glossary Term Bidirectional meter S0 mixed signal Consumption meter with return inhibit Power consumption Optical meter reader Digital meter Abbreviation Bidirectional meters are used to measure the amount of electricity that is fed by the photovoltaic system into the public network. A consumption meter is an electricity meter that records the amount of energy generated by a system. It normally has a return inhibit, i.e. the (low) amount of energy consumed by the inverter itself is not taken into account during periods without production. Total of all consumers in the home; the PV power must not be included! Optical device for reading the consumption meters. It is not necessary to adjust the sensitivity because it adjusts automatically to each meter. The reader is able to read both passive optical displays (meter discs) and active optical displays (pulse LED) Energy meter for displaying the actual energy consumption and the actual usage period, which is also integrated in a communication network. Application note for 0 % / 70 % feed-in regulation Page

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