A power flow calculation on a pandapower network can fail to converge (or fail to run at all) for a vast variety of reasons, which often makes debugging difficult, annoying and time consuming. To help with that, the diagnostic function automatically checks pandapower networks for the most common issues leading to errors. It provides logging output and diagnoses with a controllable level of detail.
To demonstrate the usage of the diagnostic function we will use a very basic exemplary pandapower network with several flaws.
There will be no further explenation on how to create pandapower networks since there's a separate tutorial available in this regard.
import warnings
warnings.filterwarnings("ignore")
# imports the pandapower module
import pandapower as pp
# defines a function that creates an example network, which will be used a lot in this tutorial
# run this code first in order for the examples to work
def faulty_example_network():
net = pp.create_empty_network()
pp.create_bus(net, name = "110 kV bar", vn_kv = 110, type = 'b', in_service = 'True')
pp.create_bus(net, name = "20 kV bar", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 2", vn_kv = 30, type = 'b')
pp.create_bus(net, name = "bus 3", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 4", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 5", vn_kv = -20, type = 'b')
pp.create_bus(net, name = "bus 6", vn_kv = 20, type = 'b')
pp.create_ext_grid(net, 0, vm_pu = 1)
pp.create_line(net, name = "line 0", from_bus = 1, to_bus = 2, length_km = 0, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 1", from_bus = 2, to_bus = 3, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 2", from_bus = 3, to_bus = 4, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 3", from_bus = 4, to_bus = 5, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 4", from_bus = 5, to_bus = 6, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 5", from_bus = 6, to_bus = 1, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_transformer_from_parameters(net, hv_bus = 1, lv_bus = 0, i0_percent= 0.038, pfe_kw = 11.6,
vkr_percent = 0.322, sn_mva = 40.0, vn_lv_kv = 22.0,
vn_hv_kv = 110.0, vk_percent = 17.8)
pp.create_load(net, 2, p_mw = -1, q_mvar = 0.200, name = "load 0")
pp.create_load(net, 3, p_mw = 1, q_mvar = 0.200, name = "load 1")
pp.create_load(net, 4, p_mw = 1, q_mvar = 0.200, name = "load 2")
pp.create_load(net, 5, p_mw = 1, q_mvar = 0.200, name = "load 3")
pp.create_load(net, 6, p_mw = 1, q_mvar = 0.200, name = "load 4")
pp.create_switch(net, bus = 1, element = 0, et = 'l')
pp.create_switch(net, bus = 2, element = 0, et = 'l')
pp.create_switch(net, bus = 2, element = 1, et = 'l')
pp.create_switch(net, bus = 3, element = 1, et = 'l')
pp.create_switch(net, bus = 3, element = 2, et = 'l')
pp.create_switch(net, bus = 4, element = 2, et = 'l')
pp.create_switch(net, bus = 4, element = 3, et = 'l', closed = False)
pp.create_switch(net, bus = 5, element = 3, et = 'l')
pp.create_switch(net, bus = 5, element = 4, et = 'l', closed = False)
pp.create_switch(net, bus = 6, element = 4, et = 'l', closed = False)
pp.create_switch(net, bus = 6, element = 5, et = 'l')
pp.create_switch(net, bus = 1, element = 5, et = 'l')
return net
# creates the example network
faulty_net = faulty_example_network()
pp.runpp(faulty_net)
--------------------------------------------------------------------------- LoadflowNotConverged Traceback (most recent call last) ~\AppData\Local\Temp\ipykernel_20180\2418505463.py in <module> 1 # creates the example network 2 faulty_net = faulty_example_network() ----> 3 pp.runpp(faulty_net) ~\Documents\Python Scripts\pandapower\pandapower\run.py in runpp(net, algorithm, calculate_voltage_angles, init, max_iteration, tolerance_mva, trafo_model, trafo_loading, enforce_q_lims, check_connectivity, voltage_depend_loads, consider_line_temperature, run_control, distributed_slack, tdpf, tdpf_delay_s, **kwargs) 239 _check_bus_index_and_print_warning_if_high(net) 240 _check_gen_index_and_print_warning_if_high(net) --> 241 _powerflow(net, **kwargs) 242 243 ~\Documents\Python Scripts\pandapower\pandapower\powerflow.py in _powerflow(net, **kwargs) 84 result = _run_pf_algorithm(ppci, net["_options"], **kwargs) 85 # read the results (=ppci with results) to net ---> 86 _ppci_to_net(result, net) 87 88 ~\Documents\Python Scripts\pandapower\pandapower\powerflow.py in _ppci_to_net(result, net) 186 algorithm = net["_options"]["algorithm"] 187 max_iteration = net["_options"]["max_iteration"] --> 188 raise LoadflowNotConverged("Power Flow {0} did not converge after " 189 "{1} iterations!".format(algorithm, max_iteration)) 190 else: LoadflowNotConverged: Power Flow nr did not converge after 10 iterations!
As you can see there is at least one error in our network that prevents the load flow calculation from running properly.
# diagnoses the faulty network
pp.diagnostic(faulty_net)
hp.pandapower.diagnostic_reports - WARNING: _____________ PANDAPOWER DIAGNOSTIC TOOL _____________ hp.pandapower.diagnostic_reports - INFO: Checking for missing bus indices... hp.pandapower.diagnostic_reports - INFO: hp.pandapower.diagnostic_reports - INFO: PASSED: No missing bus indices found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for elements without a connection to an external grid... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Disconnected section found, consisting of the following elements: hp.pandapower.diagnostic_reports - WARNING: buses: [5] hp.pandapower.diagnostic_reports - WARNING: switches: [7, 8] hp.pandapower.diagnostic_reports - WARNING: lines: [3] hp.pandapower.diagnostic_reports - WARNING: loads: [3] hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 5 disconnected element(s) found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for connections of different voltage levels... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0 connects bus 1: 20 kV bar (vn_kv = 20.0) and bus 2: bus 2 (vn_kv = 30.0) hp.pandapower.diagnostic_reports - WARNING: line 1 connects bus 2: bus 2 (vn_kv = 30.0) and bus 3: bus 3 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: line 3 connects bus 4: bus 4 (vn_kv = 20.0) and bus 5: bus 5 (vn_kv = -20.0) hp.pandapower.diagnostic_reports - WARNING: line 4 connects bus 5: bus 5 (vn_kv = -20.0) and bus 6: bus 6 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 4 element(s) that connect different voltage levels found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for impedance values close to zero... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0: r_ohm <= 0.001 or x_ohm <= 0.001 hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge after replacing implausible elements with switches. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 element(s) with impedance values close to zero found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for components with deviating nominal voltages... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Trafo(s) [0]: hv and lv connectors seem to be swapped hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 component(s) with deviating nominal voltages found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for invalid_values... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: bus: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'bus 5' with attribute 'vn_kv' = -20.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: line: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'line 0' with attribute 'length_km' = 0.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 2 invalid values found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for overload... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Overload check failed: Power flow still does not converge with load and generation scaled down to 0.1 percent. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No buses with multiple gens and/or ext_grids found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking switch configuration... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge with all switches closed. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: External grid found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for usage of wrong reference system... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Found load 0: 'load 0' with p_mw = -1.0. In load reference system p_mw should be positive. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: Found 1 load(s) with negative p_mw. In load reference system, p_mw should be positive. If the intention was to model a constant generation, please use an sgen instead. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No elements with deviations from std_type found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: numba_comparison failed due to the following error: hp.pandapower.diagnostic_reports - WARNING: Power Flow nr did not converge after 10 iterations! hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No parallel switches found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{'disconnected_elements': [{'buses': [5],
'switches': [7, 8],
'lines': [3],
'loads': [3]}],
'different_voltage_levels_connected': {'lines': [0, 1, 3, 4]},
'impedance_values_close_to_zero': [{'line': [0]},
{'loadflow_converges_with_switch_replacement': False}],
'nominal_voltages_dont_match': {'trafo': {'hv_lv_swapped': [0]}},
'invalid_values': {'bus': [(5, 'vn_kv', -20.0, '>0')],
'line': [(0, 'length_km', 0.0, '>0')]},
'overload': {'load': False, 'generation': False},
'wrong_switch_configuration': False,
'wrong_reference_system': {'loads': [0]}}
For a more compact report, there a two options that can be passed as arguments to the diagnostic function:
warnings_only = True : only positive check results (errors found) will be in the report
detailed_report = False: only error summaries, no detailed error descriptions
The default setting is:
diagnostic(net, warnings_only = False, detailed_report = True)
# report with warnings_only
pp.diagnostic(faulty_net, warnings_only=True)
hp.pandapower.diagnostic_reports - WARNING: _____________ PANDAPOWER DIAGNOSTIC TOOL _____________ hp.pandapower.diagnostic_reports - WARNING: Checking for elements without a connection to an external grid... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Disconnected section found, consisting of the following elements: hp.pandapower.diagnostic_reports - WARNING: buses: [5] hp.pandapower.diagnostic_reports - WARNING: switches: [7, 8] hp.pandapower.diagnostic_reports - WARNING: lines: [3] hp.pandapower.diagnostic_reports - WARNING: loads: [3] hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 5 disconnected element(s) found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for connections of different voltage levels... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0 connects bus 1: 20 kV bar (vn_kv = 20.0) and bus 2: bus 2 (vn_kv = 30.0) hp.pandapower.diagnostic_reports - WARNING: line 1 connects bus 2: bus 2 (vn_kv = 30.0) and bus 3: bus 3 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: line 3 connects bus 4: bus 4 (vn_kv = 20.0) and bus 5: bus 5 (vn_kv = -20.0) hp.pandapower.diagnostic_reports - WARNING: line 4 connects bus 5: bus 5 (vn_kv = -20.0) and bus 6: bus 6 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 4 element(s) that connect different voltage levels found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for impedance values close to zero... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0: r_ohm <= 0.001 or x_ohm <= 0.001 hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge after replacing implausible elements with switches. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 element(s) with impedance values close to zero found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for components with deviating nominal voltages... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Trafo(s) [0]: hv and lv connectors seem to be swapped hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 component(s) with deviating nominal voltages found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for invalid_values... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: bus: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'bus 5' with attribute 'vn_kv' = -20.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: line: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'line 0' with attribute 'length_km' = 0.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 2 invalid values found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for overload... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Overload check failed: Power flow still does not converge with load and generation scaled down to 0.1 percent. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking switch configuration... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge with all switches closed. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for usage of wrong reference system... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Found load 0: 'load 0' with p_mw = -1.0. In load reference system p_mw should be positive. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: Found 1 load(s) with negative p_mw. In load reference system, p_mw should be positive. If the intention was to model a constant generation, please use an sgen instead. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{'disconnected_elements': [{'buses': [5],
'switches': [7, 8],
'lines': [3],
'loads': [3]}],
'different_voltage_levels_connected': {'lines': [0, 1, 3, 4]},
'impedance_values_close_to_zero': [{'line': [0]},
{'loadflow_converges_with_switch_replacement': False}],
'nominal_voltages_dont_match': {'trafo': {'hv_lv_swapped': [0]}},
'invalid_values': {'bus': [(5, 'vn_kv', -20.0, '>0')],
'line': [(0, 'length_km', 0.0, '>0')]},
'overload': {'load': False, 'generation': False},
'wrong_switch_configuration': False,
'wrong_reference_system': {'loads': [0]}}
# report with summaries only
pp.diagnostic(faulty_net, report_style="compact")
hp.pandapower.diagnostic_reports - WARNING:
_____________ PANDAPOWER DIAGNOSTIC TOOL _____________
hp.pandapower.diagnostic_reports - INFO: missing_bus_indices:
hp.pandapower.diagnostic_reports - INFO:
hp.pandapower.diagnostic_reports - INFO: PASSED: No missing bus indices found.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: disconnected_elements:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: disonnected_section: {'buses': [5], 'switches': [7, 8], 'lines': [3], 'loads': [3]}
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: different_voltage_levels_connected:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: lines:
hp.pandapower.diagnostic_reports - WARNING: line 0: buses [1, 2]
hp.pandapower.diagnostic_reports - WARNING: line 1: buses [2, 3]
hp.pandapower.diagnostic_reports - WARNING: line 3: buses [4, 5]
hp.pandapower.diagnostic_reports - WARNING: line 4: buses [5, 6]
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: impedance_values_close_to_zero:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: line 0: r_ohm <= 0.001 or x_ohm <= 0.001
hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge after replacing implausible elements with switches.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: nominal_voltages_dont_match:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: trafo:
hp.pandapower.diagnostic_reports - WARNING: hv_lv_swapped: [0]
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: invalid_values:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: bus:
hp.pandapower.diagnostic_reports - WARNING: bus 5: 'vn_kv' = -20.0 (restriction: >0)
hp.pandapower.diagnostic_reports - WARNING: line:
hp.pandapower.diagnostic_reports - WARNING: line 0: 'length_km' = 0.0 (restriction: >0)
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: overload:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: Overload check failed: Power flow still does not converge with load and generation scaled down to 0.1 percent.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - INFO: PASSED: No buses with multiple gens and/or ext_grids found.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: wrong_switch_configuration:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge with all switches closed.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - INFO: PASSED: External grid found.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: wrong_reference_system:
hp.pandapower.diagnostic_reports - WARNING:
hp.pandapower.diagnostic_reports - WARNING: loads [0]: wrong reference system.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - INFO: PASSED: No elements with deviations from std_type found.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: numba_comparison failed due to the following error:
hp.pandapower.diagnostic_reports - WARNING: Power Flow nr did not converge after 10 iterations!
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - INFO: PASSED: No parallel switches found.
hp.pandapower.diagnostic_reports - WARNING:
--------
hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{'disconnected_elements': [{'buses': [5],
'switches': [7, 8],
'lines': [3],
'loads': [3]}],
'different_voltage_levels_connected': {'lines': [0, 1, 3, 4]},
'impedance_values_close_to_zero': [{'line': [0]},
{'loadflow_converges_with_switch_replacement': False}],
'nominal_voltages_dont_match': {'trafo': {'hv_lv_swapped': [0]}},
'invalid_values': {'bus': [(5, 'vn_kv', -20.0, '>0')],
'line': [(0, 'length_km', 0.0, '>0')]},
'overload': {'load': False, 'generation': False},
'wrong_switch_configuration': False,
'wrong_reference_system': {'loads': [0]}}
# diagnoses the faulty network
pp.diagnostic(faulty_net)
hp.pandapower.diagnostic_reports - WARNING: _____________ PANDAPOWER DIAGNOSTIC TOOL _____________ hp.pandapower.diagnostic_reports - INFO: Checking for missing bus indices... hp.pandapower.diagnostic_reports - INFO: hp.pandapower.diagnostic_reports - INFO: PASSED: No missing bus indices found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for elements without a connection to an external grid... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Disconnected section found, consisting of the following elements: hp.pandapower.diagnostic_reports - WARNING: buses: [5] hp.pandapower.diagnostic_reports - WARNING: switches: [7, 8] hp.pandapower.diagnostic_reports - WARNING: lines: [3] hp.pandapower.diagnostic_reports - WARNING: loads: [3] hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 5 disconnected element(s) found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for connections of different voltage levels... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0 connects bus 1: 20 kV bar (vn_kv = 20.0) and bus 2: bus 2 (vn_kv = 30.0) hp.pandapower.diagnostic_reports - WARNING: line 1 connects bus 2: bus 2 (vn_kv = 30.0) and bus 3: bus 3 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: line 3 connects bus 4: bus 4 (vn_kv = 20.0) and bus 5: bus 5 (vn_kv = -20.0) hp.pandapower.diagnostic_reports - WARNING: line 4 connects bus 5: bus 5 (vn_kv = -20.0) and bus 6: bus 6 (vn_kv = 20.0) hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 4 element(s) that connect different voltage levels found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for impedance values close to zero... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: line 0: r_ohm <= 0.001 or x_ohm <= 0.001 hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge after replacing implausible elements with switches. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 element(s) with impedance values close to zero found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for components with deviating nominal voltages... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Trafo(s) [0]: hv and lv connectors seem to be swapped hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 1 component(s) with deviating nominal voltages found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for invalid_values... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: bus: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'bus 5' with attribute 'vn_kv' = -20.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: line: hp.pandapower.diagnostic_reports - WARNING: Invalid value found: 'line 0' with attribute 'length_km' = 0.0 (data type: <class 'numpy.float64'>). Valid input needs to be >0. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: 2 invalid values found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for overload... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Overload check failed: Power flow still does not converge with load and generation scaled down to 0.1 percent. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No buses with multiple gens and/or ext_grids found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking switch configuration... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge with all switches closed. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: External grid found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking for usage of wrong reference system... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Found load 0: 'load 0' with p_mw = -1.0. In load reference system p_mw should be positive. hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: SUMMARY: Found 1 load(s) with negative p_mw. In load reference system, p_mw should be positive. If the intention was to model a constant generation, please use an sgen instead. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No elements with deviations from std_type found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: numba_comparison failed due to the following error: hp.pandapower.diagnostic_reports - WARNING: Power Flow nr did not converge after 10 iterations! hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No parallel switches found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{'disconnected_elements': [{'buses': [5],
'switches': [7, 8],
'lines': [3],
'loads': [3]}],
'different_voltage_levels_connected': {'lines': [0, 1, 3, 4]},
'impedance_values_close_to_zero': [{'line': [0]},
{'loadflow_converges_with_switch_replacement': False}],
'nominal_voltages_dont_match': {'trafo': {'hv_lv_swapped': [0]}},
'invalid_values': {'bus': [(5, 'vn_kv', -20.0, '>0')],
'line': [(0, 'length_km', 0.0, '>0')]},
'overload': {'load': False, 'generation': False},
'wrong_switch_configuration': False,
'wrong_reference_system': {'loads': [0]}}
Bus 5, line 3, load 3 as well as switches 7 and 8 are not connected to an external grid. To fix that, we close switches 8 and 9.
faulty_net.switch.closed.loc[8, 9] = True
Lines 0, 1, 3 and 4 connect different voltage levels. Apparently bus 2 (30 kV) and bus 5 (-20 kV) have wrong voltage levels values. We change that to 20 kV.
faulty_net.bus.vn_kv.loc[2, 5] = 20
Line 0 is 0 km long (and therefore its impedance is 0 ohm). We change the length to 1 km.
faulty_net.line.length_km.at[0] = 1
We fix that by swapping the hv and lv connectors of trafo 0 back.
faulty_net.trafo.hv_bus.at[0] = 0
faulty_net.trafo.lv_bus.at[0] = 1
Load 0 has a p_mw value of -1. Since pandapower uses the load reference system for loads, the value should either be positive or an sgen should be used. We assume the former and change the value to 1.
faulty_net.load.p_mw.at[0] = 1
# new diagnosis to check, whether we fixed all errors
pp.diagnostic(faulty_net)
hp.pandapower.diagnostic_reports - WARNING: _____________ PANDAPOWER DIAGNOSTIC TOOL _____________ hp.pandapower.diagnostic_reports - INFO: Checking for missing bus indices... hp.pandapower.diagnostic_reports - INFO: hp.pandapower.diagnostic_reports - INFO: PASSED: No missing bus indices found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No problematic switches found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No connection of different voltage levels found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No elements with impedance values close to zero found... hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No components with deviating nominal voltages found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No invalid values found hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: Power flow converges. No overload found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No buses with multiple gens and/or ext_grids found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: Power flow converges. Switch configuration seems ok. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: External grid found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: correct reference system hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No elements with deviations from std_type found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No results with deviations between numba = True vs. False found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - INFO: PASSED: No parallel switches found. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{}
Apparently, all errors have been fixed. So we can try again to run a loadflow calculation.
pp.runpp(faulty_net)
faulty_net
This pandapower network includes the following parameter tables: - bus (7 elements) - load (5 elements) - switch (12 elements) - ext_grid (1 element) - line (6 elements) - trafo (1 element) and the following results tables: - res_bus (7 elements) - res_line (6 elements) - res_trafo (1 element) - res_ext_grid (1 element) - res_load (5 elements) - res_switch (12 elements)
Now the loadflow calculation runs without problems.
Other errors the diagnostic function can help to identify, are networks with too much load or wrong switch configurations. The function automatically checks, if the loadflow converges with all loads and generation scaled down to 0.1% or with all switches closed.
# imports the pandapower module
import pandapower as pp
# defines a function that creates an example network
# run this code first in order for the examples to work
def overload_example_network():
net = pp.create_empty_network()
pp.create_bus(net, name = "110 kV bar", vn_kv = 110, type = 'b')
pp.create_bus(net, name = "20 kV bar", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 2", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 3", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 4", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 5", vn_kv = 20, type = 'b')
pp.create_bus(net, name = "bus 6", vn_kv = 20, type = 'b')
pp.create_ext_grid(net, 0, vm_pu = 1)
pp.create_line(net, name = "line 0", from_bus = 1, to_bus = 2, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 1", from_bus = 2, to_bus = 3, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 2", from_bus = 3, to_bus = 4, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 3", from_bus = 4, to_bus = 5, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 4", from_bus = 5, to_bus = 6, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_line(net, name = "line 5", from_bus = 6, to_bus = 1, length_km = 1, std_type = "NAYY 4x150 SE")
pp.create_transformer_from_parameters(net, hv_bus = 0, lv_bus = 1, i0_percent= 0.038, pfe_kw = 11.6,
vkr_percent = 0.322, sn_mva = 40.0, vn_lv_kv = 22.0,
vn_hv_kv = 110.0, vk_percent = 17.8)
pp.create_load(net, 2, p_mw = 100, q_mvar = 0.2, name = "load 0")
pp.create_load(net, 3, p_mw = 100, q_mvar = 0.2, name = "load 1")
pp.create_load(net, 4, p_mw = 100, q_mvar = 0.2, name = "load 2")
pp.create_load(net, 5, p_mw = 100, q_mvar = 0.2, name = "load 3")
pp.create_load(net, 6, p_mw = 100, q_mvar = 0.2, name = "load 4")
pp.create_switch(net, bus = 1, element = 0, et = 'l')
pp.create_switch(net, bus = 2, element = 0, et = 'l')
pp.create_switch(net, bus = 2, element = 1, et = 'l')
pp.create_switch(net, bus = 3, element = 1, et = 'l')
pp.create_switch(net, bus = 3, element = 2, et = 'l')
pp.create_switch(net, bus = 4, element = 2, et = 'l')
pp.create_switch(net, bus = 4, element = 3, et = 'l', closed = 0)
pp.create_switch(net, bus = 5, element = 3, et = 'l')
pp.create_switch(net, bus = 5, element = 4, et = 'l')
pp.create_switch(net, bus = 6, element = 4, et = 'l')
pp.create_switch(net, bus = 6, element = 5, et = 'l')
pp.create_switch(net, bus = 1, element = 5, et = 'l')
return net
overload_net = overload_example_network()
pp.runpp(overload_net)
--------------------------------------------------------------------------- LoadflowNotConverged Traceback (most recent call last) ~\AppData\Local\Temp\ipykernel_20180\528784445.py in <module> 1 overload_net = overload_example_network() ----> 2 pp.runpp(overload_net) ~\Documents\Python Scripts\pandapower\pandapower\run.py in runpp(net, algorithm, calculate_voltage_angles, init, max_iteration, tolerance_mva, trafo_model, trafo_loading, enforce_q_lims, check_connectivity, voltage_depend_loads, consider_line_temperature, run_control, distributed_slack, tdpf, tdpf_delay_s, **kwargs) 239 _check_bus_index_and_print_warning_if_high(net) 240 _check_gen_index_and_print_warning_if_high(net) --> 241 _powerflow(net, **kwargs) 242 243 ~\Documents\Python Scripts\pandapower\pandapower\powerflow.py in _powerflow(net, **kwargs) 84 result = _run_pf_algorithm(ppci, net["_options"], **kwargs) 85 # read the results (=ppci with results) to net ---> 86 _ppci_to_net(result, net) 87 88 ~\Documents\Python Scripts\pandapower\pandapower\powerflow.py in _ppci_to_net(result, net) 186 algorithm = net["_options"]["algorithm"] 187 max_iteration = net["_options"]["max_iteration"] --> 188 raise LoadflowNotConverged("Power Flow {0} did not converge after " 189 "{1} iterations!".format(algorithm, max_iteration)) 190 else: LoadflowNotConverged: Power Flow nr did not converge after 10 iterations!
pp.diagnostic(overload_net, warnings_only = True)
hp.pandapower.diagnostic_reports - WARNING: _____________ PANDAPOWER DIAGNOSTIC TOOL _____________ hp.pandapower.diagnostic_reports - WARNING: Checking for overload... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: overload found: Power flow converges with load scaled down to 0.1 percent. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: Checking switch configuration... hp.pandapower.diagnostic_reports - WARNING: hp.pandapower.diagnostic_reports - WARNING: Power flow still does not converge with all switches closed. hp.pandapower.diagnostic_reports - WARNING: -------- hp.pandapower.diagnostic_reports - WARNING: _____________ END OF PANDAPOWER DIAGNOSTIC _____________
{'overload': {'load': True, 'generation': False},
'wrong_switch_configuration': False}
As you can see, with loads scaled down, the loadflow converges, which helps to isolate the problem.