822 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 54, NO. 1, JANUARY/FEBRUARY 2018 Modeling, Simulation, and Testing of Switching Surge Transients in Rapid Transit Vehicles DC Power Systems Maxime Berger , Student Member, IEEE, Jean-Pierre Magalhaes Grave , Carl Lavertu, Member, IEEE, Ilhan Kocar, Senior Member, IEEE, Jean Mahseredjian , Fellow, IEEE, and Daniele Ferrara , Member, IEEE Abstract—During the operation of dc rapid transit systems, the rail passenger vehicles are subjected to surge transient events that can damage the on-board equipment and cause service interruption. During the testing phase, vehicle manufacturers must demonstrate the performance of the vehicles under the specified transients. However, system testing is generally not available during design. Engineering analysis must be performed to ensure that the design will meet the transient requirements, and that the overvoltage and overcurrent protective devices are coordinated on a system level. In response to these design challenges, detailed time-domain simulation models of a switching surge transient generator and the vehicle equipment have been developed and validated experimentally. These models are used to evaluate vehicle system parameters sensitivity, as well as to provide design guidelines for increased vehicle power system safety, reliability, and availability. Index Terms—dc power systems, electromagnetic transients program (EMTP), power system protection, railway safety, surge protection. I. INTRODUCTION APID transit systems are widely used in North America for high volume passenger transportation. They are composed of rail passenger vehicles operating as multivehicle trains on a local dc traction power system [1]. Substations are equipped with 6- and 12-pulse diode rectifiers. The power from the traction system substations is delivered to the moving trains by a third-rail system, or an overhead catenary system at voltage between 600 and 1500 V [2], [3]. During operation, the rail passenger vehicles are facing surge transient events that can seriously damage the on-board equip- R Manuscript received May 25, 2017; revised September 5, 2017; accepted October 2, 2017. Date of publication October 10, 2017; date of current version January 18, 2018. Paper 2017-ESafC-0374.R1, presented at the 2017 Electrical Safety Workshop, Reno, NV, USA, Jan. 28–Feb. 3, and approved for publication in the IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS by the Electrical Safety Committee of the IEEE Industry Applications Society. (Corresponding author: Maxime Berger.) M. Berger is with Bombardier Transportation, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada (e-mail: maxime.berger@polymtl.ca). J.-P. M. Grave, C. Lavertu, and D. Ferrara are with Bombardier Transportation, St-Bruno, QC J3V 6E6, Canada (e-mail: jean-pierre.magalhaes@rail. bombardier.com; carl.lavertu@rail.bombardier.com; danfer80@outlook.com). J. Mahseredjian and I. Kocar are with Polytechnique Montreal, Montreal, QC H3T 1J4, Canada (e-mail: jean.mahseredjian@polymtl.ca; ilhan.kocar@ polymtl.ca). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TIA.2017.2761870 Fig. 1. Available magnetic energy in a typical dc rapid transit system. ment and cause major service interruption [4]–[7]. These surges can be predictable or unpredictable [8]. In dc rapid transit systems, surge transients are mainly the consequence of vehicle regenerative braking action [5], lightning strikes [6], [9]–[11], rectifier ac-side capacitor bank switching [12], and stored magnetic energy release at fault clearing [13]. The waveform and the energy level of the surge depends on the nature of the surge transient. High-energy switching surge results from the release of magnetic energy stored into the dc traction system track at fault clearing. Fig. 1 shows an evaluation of the magnetic energy stored as a function of the fault distance from a typical Montreal subway system substation (750 V, 2.5 MW, 12-pulse rectifier). This curve is obtained using the developed substation model in [1]. At fault clearing, if the dc traction system is not receptive, the energy needs to be dissipated by both the wayside and the vehicle on-board equipment. Maximum energy condition typically occurs at a close distance from the substation [2]. Surge transient specifications for rail vehicles are generally based on standardized waveforms, but transit authorities may specify their own requirements based on the knowledge of their local traction system. During the testing phase, vehicle manufacturers must demonstrate the performance of the vehicles under the specified transients [14]. Experiences have shown that the investigation of protection solutions during the testing phase is costly [15]. Complete analysis, considering the behavior of the on-board equipment, should be performed during the design 0093-9994 © 2017 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications standards/publications/rights/index.html for more information. BERGER et al.: MODELING, SIMULATION, AND TESTING OF SWITCHING SURGE TRANSIENTS Fig. 2. 823 Typical dc rapid transit vehicle primary power system. phase to reduce the risk of protection issues and enhance the system operational performance, such as safety, reliability, and availability. Laboratory testing also showed that the behavior of the vehicle under surge transients is not always intuitive. This is explained by the complex interaction between the propulsion inverters and auxiliary power supply (APS) LC-filters, the different overcurrent and overvoltage protective devices mechanisms, and the presence of electronic protection schemes. It is also worth to mention that there is currently no standardized approach for surge transient analysis in dc rapid transit systems [13], [16]. This paper contributes to the knowledge in modeling dc rapid transit vehicles for simulation, and analysis of high-energy switching surge transients. In Section II, detailed models of vehicle’s equipment and protective devices are developed. In Section III, these models are implemented in the Electromagnetic Transients Program (EMTP) [17], and validated experimentally using data gathered during surge transient testing. Based on the experimental results, guidelines on the required level of modeling details are provided for accurate simulations. In Section IV, the developed simulation model is used to evaluate the influence of the main system parameters on the overall vehicle operational performance under switching surge transients. Design guidelines are provided based on the simulation results. Important safety related aspects are also discussed. II. VEHICLE MODELING A. Overview of the Vehicle Primary Power System A typical dc rapid transit vehicle on-board primary power system is shown in Fig. 2. The propulsion system of modern vehicles is composed of one or two traction inverter(s) each connected to one or two threephase traction motor(s). A brake chopper system is also used to dissipate extra braking energy in case of nonreceptivity of the dc traction system during dynamic braking operation [18]. The brake chopper can also act as an overvoltage protective device upon detection of overvoltage conditions. A high-speed circuit breaker (HSCB) is also generally used to protect the propulsion system against internal faults. Fig. 3. High-speed circuit breaker (HSCB) timing diagram. The train auxiliary subsystems are supplied by an APS. The APS converts the dc traction power system high voltage supply into lower galvanically isolated dc and ac supplies. The auxiliary fuse is used to protect the APS against internal faults, while surge arrester or crowbar circuit [16] may be used for overvoltage protection inside the APS. Input diodes are also used in many applications to protect against negative voltage events. Both the propulsion system and the APS are also equipped with input LC-filter to meet the railway electromagnetic compatibility requirements. Both air- and iron-core inductors are used. B. Equipment Models 1) High-Speed Circuit Breaker (HSCB): The HSCB model has been previously presented in [1] in the context of transient overcurrent protection in railway vehicles, but it is summarized here again for the sake of integrity of the presented material. HSCB are typically defined using first-order circuit approximation [19]. The HSCB model consists of a controlled voltage source used to replicate the circuit breaker arcing voltage as shown in Fig. 3. Laboratory testing confirmed that this model is accurate enough to approximate the energy dissipated into the arc during current interruption. In Fig. 3, when the circuit breaker current if exceeds the current setting Id , a trip signal is sent to the HSCB trip coil by its internal detection circuit. As seen in [1], the detection time td decreases with the prospective current Iss and increases with the circuit time-constant (L/R). An opening delay tm is present before the breaker contacts start to open. This delay decreases with the initial rate-of-rise of the current [20]. 824 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 54, NO. 1, JANUARY/FEBRUARY 2018 the selection of the pre-arc I 2 t threshold because it depends on circuit parameters such as the operating voltage, the frequency, and the L/R ratio. It is also recommended in [24] to add a 25% margin when using the pre-arc I 2 t energy (2) i2 tm es (t) = (im es (t))2 dt. Fig. 4. Equivalent circuit of the current-limiting fuse model. Once the contacts start to open, an arc voltage ua is introduced into the circuit, and is used to rapidly break the dc current. The initial arc voltage is represented by a step voltage Ui of duration ti . As the distance between the contacts increases, the arcing voltage ua starts to increase rapidly. This process is approximated by a ramp function with slope β. The peak letthrough current Ip occurs at time tp . For standard HSCB, the difference between tp and td is typically smaller than 10 ms [2], [21]. The arcing voltage ua then continues to increase up to a maximum value Ua , which is considered constant following manufacturer’s data for a given arc chute [20]. During the constant arc voltage period ta, the arcing current ia decreases. The rate-of-decrease of the arcing current depends on the circuit inductance and the maximum arc voltage value Ua . Once the arcing current ia reaches zero, the arc extinguishes. 2) Current-Limiting Fuse: The equivalent circuit of the current-limiting fuse model is shown in Fig. 4 and is detailed in Fig. 5. For modeling purpose, the current-limiting fuse model is divided into two sections: the melting energy calculation, and the arcing mechanism. For transient analysis by simulation, the melting energy calculation is performed using both the fuse time–current curve (TCC) and the pre-arc I 2 t data as shown in Fig. 5(a). Traditional assessment of fuse performance using ac rms TCC is a limited practice for transient overcurrent analysis in dc circuits. The equivalent rms value of the instantaneous current needs to be calculated to use the ac rms TCC. This is because there is as many equivalent TCC in dc circuit as available fault current waveforms in the system [22]. An interesting representation of the influence of the time-constant on the fuse TCC is shown in [23]. In the model of Fig. 5(a), the fuse melting time is first evaluated by comparing the measured rms current with the fuse ac rms melting TCC, and then by calculating the equivalent per-unit melting energy using (1). The total melting time is the time required for (1) to reach a value of 1 p.u. [15] 1 dt. (1) T rm (t) = tm f (t) Current-limiting fuse TCC is generally given down to a minimum melting time of 10 ms. Even if it is not clearly represented on the TCC, current-limiting fuse can break higher fault current in less than 10 ms. In this operating region, the melting time highly depends on the fault current waveform. I 2 t coordination is recommended in this region according to the IEEE Std C37.48.1 [24]. In the model of Fig. 5(a), this is done by calculating the measured pre-arc (or melting) I 2 t energy using (2) and by comparing the obtained value to the pre-arc I 2 t data [25]. It is important to carefully analyze manufacturer’s data for Once it is determined that the fuse is melting from the TCC or the pre-arc I 2 t, the fuse melting process is modeled as a nonlinear equivalent resistance [see Fig. 5(d)] [26]. The resistance is adjusted to best fit the peak let-through current data of the fuse manufacturer for standardized waveforms and testing conditions. There is however a need for a standardized approach to model current-limiting fuse in time-domain tools based on available manufacturer’s data. 3) Propulsion System and APS: The equivalent model schematic for the propulsion system and the APS are given in Fig. 6. Both systems require a precharge circuit to reduce the inrush current at the energization of the converter or after running over a rail gap. This circuit is modeled by two ideal-switch and a precharge resistance. Both the traction inverter and the auxiliary converter are modeled as constant power loads behind an equivalent diode modeling the converters insulated gate bipolar transistor (IGBT) antiparallel diodes. The antiparallel diodes should be modeled because they can carry current when the voltage is negative across the filter capacitor. They need to be modeled by their equivalent nonlinear VI-characteristic to approximate their energy. Details on the constant power load model are provided in [27]. As mentioned before, both systems are equipped of input LCfilter. Capacitor and inductor equivalent series resistance should be considered to increase the model accuracy. If saturable-core inductor is used, it is important to model its saturation because once saturated, it is less effective in limiting the surge current. This has been shown to be one of the most important parameters to consider in the case of rail vehicles. This is demonstrated in Section IV. 4) Propulsion Brake Chopper: The propulsion brake chopper is also an efficient overvoltage protective device. The simplest brake chopper control logic is shown in Fig. 7. It is based on a comparator circuit with a hysteresis band. For surge transient analysis, the IGBT is modeled by an ideal controlled switch. Calculation of the energy absorbed by the brake chopper during surge transient is approximated by integrating the power dissipated by the braking resistor over time as follows: (3) Ebr (t) = vbr (t)ibr (t) dt. 5) Metal-Oxide Varistor (MOV): MOV are commonly used for overvoltage protection in dc applications. The maximum continuous operating voltage (MCOV) of the MOV is first selected based on the nominal voltage, the available temporary overvoltage in the system, as well as the permissible leakage current. Once the MCOV is defined, it is important to evaluate BERGER et al.: MODELING, SIMULATION, AND TESTING OF SWITCHING SURGE TRANSIENTS Fig. 5. Fig. 6. 825 Diagram of the current-limiting fuse model (a) melting energy calculation, (b) breaking process, (c) melting TCC, and (d) nonlinear resistance model. (a) Propulsion system model. (b) Auxiliary power supply model. the required clamping voltage by the selection of a MOV with an appropriate VI-characteristic. It is also mandatory to select a MOV with the necessary energy-handling capacity for the surge environment [13]. Modeling the MOV VI-characteristic is necessary for insulation coordination and to evaluate the necessary energy-handling capacity. Minimum and maximum VI-characteristic tolerances should be considered. The MOV energy is calculated using (4), and compared to the energy capability provided by the MOV manufacturers. Once again, it is important to carefully analyze manufacturer’s data because the energy rating depends on the testing conditions, which can differ between different manufacturers [28] (4) EM OV (t) = vM OV (t)iM OV (t) dt. III. EXPERIMENTAL VALIDATION OF SIMULATION MODELS A. General Procedure Fig. 7. Brake chopper equivalent circuit model. The models presented in Section II are implemented in the EMTP. The EMTP is a time-domain circuit simulation tool based on the modified augmented nodal analysis. It uses fixed time step to solve the circuit system of equations [29]. A time step of 10 μs is selected to accurately represent all the dynamics involved in the switching surge transients under study. 826 Fig. 8. IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 54, NO. 1, JANUARY/FEBRUARY 2018 Simplified schematic of the surge generator. Fig. 10. Validation of the propulsion system and HSCB models (+3 p.u. test). Fig. 11. HSCB arcing and brake chopper clamping action (+3 p.u. test). Fig. 9. Simplified schematic of the surge transient tests. (a) Propulsion system and HSCB (b) Auxiliary power supply (APS). A model of an in-house switching surge transient generator has been developed and implemented in the EMTP (see Fig. 8). The model of the propulsion system, including the HSCB and the brake chopper, is first validated with a +3 p.u., 60 kJ surge injection [see Fig. 9(a)]. The model of the APS including its current-limiting fuse is then validated with ±3 p.u., 60 kJ surge injections [see Fig. 9(b)]. Specific conditions related to each of the three tests are provided in Sections III-C and III-D. B. Modeling of the Surge Generator For the validation of the vehicle model, a custom surge transient generator has been used (see Fig. 8). It is composed of a nonreceptive substation rectifier and a series injection surge transient source. It allows to perform +/−3 kV, 60 kJ switching surge transient tests. The surge transient generator power components and the control circuitry are replicated in the simulation model for increased precision. C. Validation of the Propulsion System Model The model of the propulsion system including both the HSCB and the rheostatic brake chopper is first validated experimentally [see Fig. 9(a)]. A surge of approximately +3 p.u., and 60 kJ is applied to the propulsion system while running at full power (∼700 kW). The propulsion system has an air-core inductor. The HSCB overcurrent trip setting is set at 2.2 p.u. The test results are compared with the simulation results in Fig. 10. Both the surge voltage and the surge current are in good agreements. In the simulation results of Fig. 11, since the HSCB current exceeds its trip setting, the HSCB trips and part of the surge energy is dissipated into the HSCB arc. The brake chopper is also dissipating part of the surge energy to control the capacitor voltage between its hysteresis band (1.30–1.35 p.u.). The remaining energy is absorbed by the traction motors and the filter capacitor. D. Validation of the APS Model The model of the APS is also validated experimentally [see Fig. 9(b)]. The specific APS under test does not have an input diode but do have a saturable-core inductor. A surge of +3 p.u., 60 kJ is still injected into the APS while it is lightly loaded. The test results are also successfully compared with the simulation results in Fig. 12. From Fig. 12, it is concluded that the filter inductor saturation is an important contributing factor because the rate-of-rise of the surge current increases drastically once the inductor saturates. It can also be seen that the MOV is clamping the surge voltage BERGER et al.: MODELING, SIMULATION, AND TESTING OF SWITCHING SURGE TRANSIENTS Fig. 12. Fig. 13. Fig. 15. Impact of the HSCB on the propulsion units surge current. Fig. 16. Impact of the HSCB on the capacitor voltage. 827 Validation of the APS model (+3 p.u. test). Calculation of the energy absorbed by the MOV (+3 p.u. test). these diodes and evaluation of their energy is mandatory to ensure that they will not be damaged. It must also be mentioned that, in both cases, the melting energy of the fuse, which is calculated using (1) and (2), is not high enough to break the fuse. By looking at Figs. 10, 12, and 14, it is also obvious that the simulation models are accurate enough to model both the propulsion system and the APS. Details such as inductor saturation, MOV VI-characteristic, fuse melting energy, HSCB detection and arcing mechanisms, brake chopper control scheme, and IGBT antiparallel diodes must be considered for accurate simulation and analysis of the entire system behavior. IV. ANALYSIS OF MAIN PARAMETERS INFLUENCE Fig. 14. Validation of the APS model (–3 p.u. test). to 1.9 p.u. at the input terminal of the APS unit. In Fig. 13, the energy absorbed by the MOV is calculated by simulation to be 49 kJ using (4). A negative test is also applied to the APS to demonstrate the importance of modeling the IGBT antiparallel diodes. The results from Fig. 14 show that the filter capacitor voltage is at some point clamped to zero because the IGBT antiparallel diodes are conducting once there is a polarity reversal at the capacitor terminals. A large amount of energy may pass through A generic vehicle surge transient test bench is implemented using the validated models. It is used to provide a better understanding of the system behavior under surge transients. Parameters sensitivity will be discussed throughout different case study. The main simulation parameters are provided in the Appendix. The vehicle is composed of two propulsion system units, and one APS. The loads are neglected to observe capacitor trapped charge. A. HSCB Detection and Arcing A surge transient of +2.25 kV, 50 kJ is applied into the propulsion system. Under surge transients, the propulsion system can benefit from the use of the HSCB if the surge current exceeds its trip setting (see Fig. 15). The HSCB can in fact reduce the energy transferred into the propulsion system, which can further reduce the level of trapped charge at the filter capacitor. HSCB tripping under high surge transient is acceptable from an operational standpoint because it can be reclosed remotely. 828 Fig. 17. IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 54, NO. 1, JANUARY/FEBRUARY 2018 Fig. 18. Impact of the inductor saturation on the APS unit. Fig. 19. Impact of the input diode on the APS antiparallel diode current. Impact of the MOV on fuse melting energy and capacitor voltage. As shown in Fig. 16, the HSCB can reduce the level of trapped charge at the filter capacitor. These trapped charges are due to limitations with simple hysteresis band control of the brake chopper. Under running condition, these trapped charges are dissipated by the traction motors. Under the no-load condition, these trapped charges may take time to discharge. This is important to be considered when selecting the brake chopper turn-on and turn-off thresholds. B. Current-Limiting Fuse and MOV Coordination Coordinating current-limiting fuse with MOV is important. Historically, surge arresters have been placed on the load side of the protection fuse for maintainability reasons associated with the localization of the equipment boxes. The disadvantage of this configuration is that the MOV acts as a low resistance during the surge transient and may lead to nuisance operation of the fuse [24]. Fuse should be avoided to break during surge transient. The surge energy should be absorbed by the MOV without breaking the fuse to allow the system to quickly recover after the event. As an example, a surge transient of +3 kV, 60 kJ is applied into the APS system. Fig. 17 shows the melting energy (in p.u.) calculated with the fuse TCC using (1). It also shows the melting energy in kA2 s calculated using (2) which is compared with the I 2 t melting energy provided by the fuse manufacturer. During surge transient, Fig. 17 shows that a MOV located on the load side of the fuse increases the melting energy seen by the fuse, but it also reduces drastically the level of trapped charge at the filter capacitor. C. Inductor Saturation In railway systems, second-order input LC-filters are typically used. Typically, at frequencies higher than 50/60 Hz, the input filter must be inductive. Cut-off frequencies in the range of 15– 35 Hz are generally selected, and the values of the capacitor and inductor are selected accordingly. It is important to design the input filter to meet the electromagnetic compatibility requirements including all the surge transients. In addition, the converter design must consider the influence of the input filter on the converter transfer functions [30]. The impact of saturable-core inductor on the ability of the filter to protect the APS unit against surge transients is shown in Fig. 18. For the same surge applied to the APS (+3 kV, 60 kJ), the air-core inductor is more effective than the saturable-core to limit the surge current rate-of-rise, which leads to a reduction of the maximum capacitor voltage. Air-core inductor should be preferred when high level of switching surge transients are expected. D. APS Input Diode Input diode cannot be used in the propulsion system because regenerative braking requires the power to flow in both directions at the converter terminals. However, for the APS, input diode can enhance the converter ability to deal with negative voltage surges. As an example, a –3 kV, 60 kJ surge is applied into the complete system (two propulsion units and one APS). The results are shown in Fig. 19. The input diode adequately protects the IGBT antiparallel diodes during the surge transient. However, when the input diode is not present, the negative surge propagates at the capacitor terminals, which leads to a polarity reversal. Since the IGBT antiparallel diodes are also in parallel with the filter capacitor, they carry part of the surge current. When there is no input diode, it is recommended to make sure that the IGBT antiparallel diodes I 2 t capability is not exceeded. BERGER et al.: MODELING, SIMULATION, AND TESTING OF SWITCHING SURGE TRANSIENTS 829 V. CONCLUSION Fig. 20. Current-limiting fuse TCC implemented in the EMTP. Overall, this paper contributes to the knowledge in modeling dc rapid transit vehicles for simulation, and analysis of highenergy switching surge transients. Detailed models of a surge transient laboratory setup including the vehicle equipment under test and the protective devices have been developed and validated experimentally. Using the developed and validated vehicle models, this paper identifies important modeling considerations for accurate analysis of surge transients in dc rapid transit vehicles. Through different case study, it also presents important design guidelines which can also be extended for any converter designed for operating in a similar surge environment. One important conclusion of this work is that vehicles should not be excluded of surge transient analysis in dc rapid transit systems. They are both part of the problems and the solutions, i.e., fault inside a vehicle can generate surge conditions, but the on-board protective devices are also a mean of absorbing surge energy circulating into the dc traction system. Experiences have also shown that the development of accurate models is a crucial step to reduce design iterations. Once the models are validated, the analysis of the system behavior is easier using simulations than by high-power laboratory testing. A good knowledge of the system behavior is mandatory to improve system safety, reliability, and availability. APPENDIX MAIN SIMULATION PARAMETERS Fig. 21. MOV VI-characteristic implemented in the EMTP. Model E. Summary of the Lessons Learned on Safety Aspects In rapid transit application, passengers’ safety and vehicle’s essential systems availability are closely related. It is important to keep supplying power to the propulsion system and the auxiliary power system to reduce the occurrence of train failure during operation. On one side, during emergency conditions, availability of the propulsion system allows to move the train to the next station for safe evacuation of the passengers. On the other side, equipment such as lighting, communication devices, ventilation system, and door control mechanisms are critical to avoid a general panic of the passengers, and safely evacuate the train during emergency conditions [27]. In this context, an appropriate coordination of the overvoltage and overcurrent protective devices is mandatory to increase the availability of the important systems. The utilization of the air-core filter inductor, and input diode for the auxiliary power system also increase system resiliency to surge transient events. These are important conclusions for increasing system availability, and, therefore, passengers’ safety. Furthermore, appropriate selection of protective devices ratings is necessary to avoid failures leading to hazardous conditions. A good knowledge of the surge environment and the limits of the protective devices (e.g., energy-handling capacity of MOV) is also critical to reduce the risk of protective device failure. Description Symbol Value – – 750 V 900 V Traction System Nominal Voltage Maximum Voltage Propulsion System (2 units) Power Set-Point Input Filter Inductor Input Filter Capacitor – Lf Cf No-Load 2.5 mH 8.2 mF Brake Chopper (2 units) Turn-on Voltage Turn-off Voltage Brake Resistor – – Rb r 1010 V 975 V 0.3 Ω Detection Id 2 kA Arc Voltage Ui Ua tm ti β 50 V 1500 V 4 ms 2 ms 480 V/ms HSCB Auxiliary Fuse Time–Current Curve Melting Energy – – See Fig. 20 140 kA2 s MOV VI-Characteristic – See Fig. 21 APS Power Set-Point Input Filter Inductor – Lf Input Filter Capacitor Cf No-Load 6.4 mH (@ 0 A) 1.7 mH (@ 275 A) 5.6 mF REFERENCES [1] M. Berger, C. Lavertu, I. Kocar, and J. Mahseredjian, “Performance analysis of DC primary power protection in railway cars using a transient analysis tool,” in Proc. IEEE Veh. Power Prop. Conf., Oct. 2015, pp. 1–7. 830 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 54, NO. 1, JANUARY/FEBRUARY 2018 [2] J. S. 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[28] IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems, IEEE Standard C62.22-2009, Jul. 2009. [29] J. Mahseredjian, V. Dinavahi, and J. A. Martinez, “Simulation tools for electromagnetic transients in power systems: Overview and challenges,” IEEE Trans. Power Del., vol. 24, no. 3, pp. 1657–1669, Jul. 2009. [30] R. W. Erickson and D. Maksimovic, Fundamental of Power Electronics, 2nd ed., Norwell, MA, USA: Kluwer, 2001. Maxime Berger (S’14) received the B.Eng. degree from the Université du Québec à Rimouski, Rimouski, QC, Canada, in 2014, and the M.A.Sc. degree in electrical engineering from Polytechnique Montréal, Montréal, QC, in 2016, where he is currently working toward the Ph.D. degree in electrical engineering. Since 2012, he has been with Bombardier Transportation, St.-Bruno, QC, where he has been working in the Systems Integration Department. His research interests include power electronics, protection, and the simulation and analysis of power systems transients. His research is supported by Bombardier Transportation, the Fonds de Recherche du QuébecNature et Technologies, and the Natural Sciences and Engineering Research Council of Canada through the Industrial Innovation Scholarship Program. Jean-Pierre Magalhaes Grave received the B.Eng. degree in electrical engineering from École Polytechnique de Montréal, Montréal, QC, Canada, in 2004. From 2004 to 2011, he was at Oerlikon Transtec, Inc., St.-Jean-sur-Richelieu, QC. Since 2011, he has been with Bombardier Transportation, St.-Bruno, QC, where he is currently an Expert in auxiliary systems. He is involved in the design, integration, and testing of auxiliary power converters, battery systems, and lighting systems for rail passenger applications. He has two U.S. Patents. Mr. Magalhaes is a registered Professional Engineer in the province of QC. Carl Lavertu (M’17) received the B.Eng. degree in electrical engineering from the Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada, in 1985. From 1985 to 1991, he was at Lauzon Lavertu Consultants, Inc., Drummondville, QC. Since 1991, he has been with Bombardier Transportation, St.Bruno, QC, where he is currently a Senior Expert in power electronics. He has been working on various rail projects, being mainly involved in the design, fabrication, and testing of traction and auxiliary power converters, battery systems, door controllers, and lighting systems. He has two U.S. Patents. Mr. Lavertu is a registered Professional Engineer in the province of QC. Ilhan Kocar (M’10–SM’13) received the Ph.D. degree in electrical engineering from the École Polytechnique de Montréal, affiliated with Université de Montréal, Montréal, QC, Canada, in 2009. He was a Project Engineer at Aselsan Electronics, Inc., St.-Bruno, QC, Canada from 1998 to 2004. He was a Research and Development Engineer at CYME International T&D, St.-Bruno, QC, Canada from 2009 to 2011. In 2011, he joined the Faculty of Electrical Engineering with Polytechnique Montreal, Montréal. He works in close collaboration with electric utilities, research organizations, and power system tool developers. His research interests include power system analysis, modeling, and simulation. Dr. Kocar is a registered Engineer in the province of QC. BERGER et al.: MODELING, SIMULATION, AND TESTING OF SWITCHING SURGE TRANSIENTS Jean Mahseredjian (F’13) received the Ph.D. degree in electrical engineering from École Polytechnique de Montréal, Montréal, QC, Canada, in 1991. From 1987 to 2004, he was at IREQ (HydroQuébec), QC, working on research and development activities related to the simulation and analysis of electromagnetic transients. In December 2004, he joined the Faculty of Electrical Engineering with École Polytechnique de Montréal. 831 Daniele Ferrara (M’16) received the B.S. degree in mathematics for engineering from Politecnico di Torino, Turin, Italy, in 2002. From 2006 to 2011, he was at various engineering firms delivering consultancy services for the aerospace industry in the Turin area. From 2011 to 2017, he held various engineering management roles at Bombardier Transportation, Vado Ligure, Italy, and St.-Bruno, QC, Canada. Since 2017, he has been with SNC-Lavalin, Montréal, QC, where he is currently the Director, Rail Control Systems. He has been working on various aerospace and rail projects, being mainly involved in the design, functional integration, and testing of different on-board and wayside systems.