EPE Association: EPE 2020 - LS4b: DC Grids Including Fault Coordination and Protections

EPE 2020 - LS4b: DC Grids Including Fault Coordination and Protections
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2020 ECCE Europe - Conference > EPE 2020 - Topic 06: Grids, Smart Grids, AC & DC > EPE 2020 - LS4b: DC Grids Including Fault Coordination and Protections

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   Approach of an Active Device Protection for Drive Inverters against Short Circuit Faults in an Open Industrial DC Grid
By Simon PULS [View]
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Abstract: An open industrial DC grid has a lot of advantages. Also new challenges arise by coupling severalDC link capacitors of inverters. This paper presents an approach and measurements of an active deviceprotection to withstand possible faults that can occur in the DC grid. In particular, robustness in the eventof faults plays a key role.

   Four Quadrant Bus-Tie Switch for Protection of Shipboard Power Systems
By Gabriele ULISSI [View]
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Abstract: The desire to increase the voltage of DC shipboard power distribution networks to the medium voltage level derives from the pressure to reduce the operating costs of such systems by increasing their efficiency. Solid state bus-tie switches are accepted to be an essential component of such installations at the low voltage level, as they allow system reconfiguration and prevent fault propagation through ultrafast fault current identification and interruption. Nevertheless, the lack of standardisation in medium voltage DC shipboard power systems hinders the development of such technologies as custom, ad hoc solutions must be found according to the selected voltage level. This paper presents a solid state bus-tie switch topology that is scalable in both power and voltage rating and relies exclusively on existing, commercially available technologies. This provides a simple, readily employable solution with the flexibility needed to bridge the technological gap in the time required for medium voltage system operating voltages to become standardised. This paper presents the prototype of the bus-tie switch and validates its scalability through extensive experimental tests.

   Impact of the Initial Transient Interruption Voltage (ITIV) on the Design and Operation of Hybrid Current-Injection DC Circuit Breakers
By Andreas JEHLE [View]
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Abstract: In hybrid DC circuit breakers with current-injection, the arc in the mechanical switch is extinguished with a current pulse. After the arc extinction, the voltage increase across the mechanical switch must be limited in order to avoid an arc reignition. The voltage across the MS is usually assumed to be equal to the voltage across the capacitor CCI in the current-injection circuit, which increases slowly due to slow charging of the capacitor by the fault current. However, in reality the voltage across capacitor CCI is usually not zero at the point in time of the arc extinction. This results in high transient voltages across the mechanical switch, the so called so-called initial transient interruption voltage (ITIV) after the arc extinguishes. However, a fast increasing ITIV can lead to a thermal reignition of the arc. Therefore, it is crucial for the design of a DC-CB to understand, which effects contribute to a high ITIV. In this paper, these causes and the influence of the ITIV are investigated. Furthermore, the beneficial influence of grading capacitors parallel to the MS is investigated. Finally, an optimization of a DC-CB including the ITIV and its results are presented for a typical implementation of a current-injection DC-CB.

   Real Time Control Hardware in The Loop test of a novel MVDC solid-state breaker
By Alessio CLERICI [View]
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Abstract: This paper assesses the development of a novel solid-state MVDC breaker and current limiter.Matlab/Simulink simulations are used as benchmark, then Real Time Control Hardware In the Loop (CHIL) simulations are performed. Same control algorithm is implemented into a microcontroller by using two different software languages: C and MicroPython. In both cases, high performances are achieved by using fast features like hardware interrupts and low level assembler code. Results are then compared in terms of simplicity, ease and speed of implementation and code readability, very important in fast prototyping activity.

EPE 2020 - LS4b: DC Grids Including Fault Coordination and Protections
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2020 ECCE Europe - Conference > EPE 2020 - Topic 06: Grids, Smart Grids, AC & DC > EPE 2020 - LS4b: DC Grids Including Fault Coordination and Protections
	[return to parent folder]

	Approach of an Active Device Protection for Drive Inverters against Short Circuit Faults in an Open Industrial DC Grid By Simon PULS	[View] [Download]
Abstract: An open industrial DC grid has a lot of advantages. Also new challenges arise by coupling severalDC link capacitors of inverters. This paper presents an approach and measurements of an active deviceprotection to withstand possible faults that can occur in the DC grid. In particular, robustness in the eventof faults plays a key role.

	Four Quadrant Bus-Tie Switch for Protection of Shipboard Power Systems By Gabriele ULISSI	[View] [Download]
Abstract: The desire to increase the voltage of DC shipboard power distribution networks to the medium voltage level derives from the pressure to reduce the operating costs of such systems by increasing their efficiency. Solid state bus-tie switches are accepted to be an essential component of such installations at the low voltage level, as they allow system reconfiguration and prevent fault propagation through ultrafast fault current identification and interruption. Nevertheless, the lack of standardisation in medium voltage DC shipboard power systems hinders the development of such technologies as custom, ad hoc solutions must be found according to the selected voltage level. This paper presents a solid state bus-tie switch topology that is scalable in both power and voltage rating and relies exclusively on existing, commercially available technologies. This provides a simple, readily employable solution with the flexibility needed to bridge the technological gap in the time required for medium voltage system operating voltages to become standardised. This paper presents the prototype of the bus-tie switch and validates its scalability through extensive experimental tests.

	Impact of the Initial Transient Interruption Voltage (ITIV) on the Design and Operation of Hybrid Current-Injection DC Circuit Breakers By Andreas JEHLE	[View] [Download]
Abstract: In hybrid DC circuit breakers with current-injection, the arc in the mechanical switch is extinguished with a current pulse. After the arc extinction, the voltage increase across the mechanical switch must be limited in order to avoid an arc reignition. The voltage across the MS is usually assumed to be equal to the voltage across the capacitor CCI in the current-injection circuit, which increases slowly due to slow charging of the capacitor by the fault current. However, in reality the voltage across capacitor CCI is usually not zero at the point in time of the arc extinction. This results in high transient voltages across the mechanical switch, the so called so-called initial transient interruption voltage (ITIV) after the arc extinguishes. However, a fast increasing ITIV can lead to a thermal reignition of the arc. Therefore, it is crucial for the design of a DC-CB to understand, which effects contribute to a high ITIV. In this paper, these causes and the influence of the ITIV are investigated. Furthermore, the beneficial influence of grading capacitors parallel to the MS is investigated. Finally, an optimization of a DC-CB including the ITIV and its results are presented for a typical implementation of a current-injection DC-CB.

	Real Time Control Hardware in The Loop test of a novel MVDC solid-state breaker By Alessio CLERICI	[View] [Download]
Abstract: This paper assesses the development of a novel solid-state MVDC breaker and current limiter.Matlab/Simulink simulations are used as benchmark, then Real Time Control Hardware In the Loop (CHIL) simulations are performed. Same control algorithm is implemented into a microcontroller by using two different software languages: C and MicroPython. In both cases, high performances are achieved by using fast features like hardware interrupts and low level assembler code. Results are then compared in terms of simplicity, ease and speed of implementation and code readability, very important in fast prototyping activity.