CIM-based AMI and GIS interfaces for energy consumption analysis and grid losses estimation

Transcription

1 IEN 2014 CIM-based AMI and GIS interfaces for energy consumption analysis and grid losses estimation Aleksander Babs Institute of Power Engineering Gdansk, Poland

2 Grid losses general model Grid losses Technical losses Non-technical losses Fixed losses Variable losses Evidence & billing losses Illegal consumption do not vary with current, independent of the actual load served by the power system (corona, leakage, dielectric, opencircuit) proportional to the square of the current (resistance and impedance losses) wrong data, unbilled meters, wrong meter parametrisation fraudulent energy consumption 2

3 Grid losses smart meters added value Smart meters typically can collect and measure: Energy consumption profiles (60s, 300s, 3600s etc) Instantaneous voltage and current per phase Profiles can be used to check if there is a possibility of illegal consumption in a given network segment. Instantaneous voltage and current readouts, captured from all meters in a LV segment at the same time, can be used to pinpoint the location of misuse. 3

4 Simplified LV radial network segment Power profiles for network segment Individial power profiles 4

5 Calculations profile based For a given period, the energy consumption measured by the balancing meter ( ) should be equal to a sum of: individual profiles, single phase meters individual profiles, three phase meters technical and non-technical losses 5

6 COSEM objects for energy profiles No Object/ Attribute Access Rights Cl Type Value Meaning name M/R/F/P/H Hourly profile : Profile created based on the states of counters for various types of energy, voltage and current every 15, 30 or 60 minutes. 1 logical_name octet-string[6] FF R-/R-/--/--/R- 2 buffer array The buffer must be recorded on a continuous basis - R-/R-/--/--/Rirregularities of the recording in the buffer are not permitted (exactly one entry in the averaging period) 3 capture_objects array {8,0-0: ,2}; {1,0-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {4,1-0: ,255,2} {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; {3,1-0: ,2}; Clock Load profile 1 status +A -A QI (+Ri) QII (+Rc) QIII (-Ri) QIV (-Rc) Pmax U L1 U L2 U L3 I L1 I L2 I L3 R-/R-/--/--/R- 4 capture_period double-longunsigned y y=60, 300, 900, 1800, 3600 s RW/R-/--/--/R- 6

7 Calculations instantaneous values With known impedance (Z i ) for a specific segment (ACLineSegment) and instantenous current value (I i ) as measured by an AMI meter, voltage drop can be calculated. For a given point in time, calculated and measured voltage values (U i ) must match at all nodes. 7

8 Required CIM classes and attributes The number of parameters required to perform the calculations is relatively low: Parameter CIM class Attribute Line id ACLineSegment IdentifiedObject.name Start/end node id TopologicalNode IdentifiedObject.name Line voltage (kv), BaseVoltage nominalvoltage Resistance per unit of length R [Ω/km], PerLengthSequenceImpedance r Reactance per unit of length X [Ω/km], PerLengthSequenceImpedance x Resistance R [Ω], ACLineSegment r Rectance X[Ω], ACLineSegment x Length [km] Conductor length Line status (0/1) SvStatus inservice 8

9 COSEM object for instantaneous values No Object/ Attribute name Cl Type Value Meaning Instantaneous voltage (phase) 3 1-0:x logical_name octet-string[6] FF x=32 in phase L1 x=52 in phase L2 (only for 3 ph meter) x=72 in phase L3 (only for 3 ph meter) Access Rights M/R/F/P/H R-/R-/--/--/R- 2 Value long-unsigned R-/R-/--/--/R- 3 scaler_unit scal_unit_type {0,35} scaling=0, unit=v, accuracy: 0.0 V R-/R-/--/--/R- Instantaneous current 3 1-0:x logical_name octet-string[6] 01001F0700FF x=31 in phase L1 R-/R-/--/--/Rx=51 in phase L2 x=71 in phase L3 2 Value long-unsigned R-/R-/--/--/R- 3 scaler_unit scal_unit_type {-1,33} scaling=-1, unit=a, accuracy: 0.0 A R-/R-/--/--/R- 9

10 Message profiles for DLMS/COSEM (IEC 62056) Client application (ERP, other client app) should be able to: selectively "write" and "read" values as well as "invoke" actions down to individual attribute level of COSEM Objects in Logical Devices located in physical devices receive unsolicited event notifications from individual COSEM Objects in Logical Devices located in physical devices. CREATE(SetRequest) CREATE(ActionRequest) CREATED(SetResponse) CREATED(ActionResponse) DLMS request for specific COSEM object or action request DLMS response with specific COSEM object or action response Client application AMI Headend + MDM 10

11 Model simplification Radial networks - easiest to handle No automatic handling of tie-points reconfiguration in LV network topology would need toplogy change event handling Full physical model would need to account for every single component of grid losses - but a selection of the most significant ones seems to be enough for a start No reactive power calculations No provision for phase load imbalance Fixed losses not very significant for LV network 11

12 Grid losses management system functions Grid losses management system for LV network should: Exchange data with AMI and GIS using CIM Detect unusual patterns in energy use historic vs actual data Perform calculation of grid losses using near-realtime data from smart meters and static topology data Determine possible trouble nodes in the network Receive filtered alerts from meters (tamper, bypass etc) as described by the EPRI CIM Interoperability Test Procedures for (Meter Reading & Control), ECITP

13 IEN 2014 Questions?