Power electronic losses of a customer-end inverter in low-voltage direct current distribution

Abstract

A low-voltage direct current (LVDC) distribution system comprises a rectifier, a DC network, and customer-end inverters (CEI) responsible for the AC supply to the electricity end-users. The CEIs can be implemented as single-phase or three-phase ones; in this paper, feasible single-and three-phase topologies are introduced and their losses are calculated using nine different power switches. Three commercially available IGBT, MOSFET, and SiC MOSFET power switches are selected for comparison. In this application, a galvanic isolation between the DC network and the customer is required. The isolation is implemented by using an isolating DC/DC converter at the CEI supply, and therefore, the input voltage of the CEI can be different from the DC network voltage. In this paper, the effect of the supply voltage level on the losses of the CEI is calculated for the nine power transistors in single-and three-phase topologies.

Multi-zone LVDC distribution systems architecture for facilitating low carbon technologies uptake

“…LVDC provides better infrastructure for managing local generation/loads to enable stable and optimal islanded operation. For example, the LVDC with a central BESS trial site reported in [13] can provide power for the relevant customers for 5 hours in the case of the main grid outages. The project detailed in [14] has also replaced an existing islanded AC microgrid by an LVDC microgrid to improve the management of the network.…”

Instantaneous conduction and switching losses in two-level voltage source inverters

“…II, it should be observed that when a controllable switch turns on the opposite free-wheeling diode turns off and in both of them there are losses (switch-on and reverse recovery, respectively). The vectors of the turn-on and turnoff switching losses (sw-on & sw-off) of the IGBT and the reverse recovery losses (rr) of the diode are given by [9] p abc sw-y,igbt (t) = f sw E sw-y I c-ds…”

“…(9) (9) describes the turn-on and turn-off switching losses and reverse-recovery losses of a 2L-VSI depending on preceding (9). It can be seen that all the other terms on the right-hand side of (9) equal zero and vanish; either because of (1 3 −d[k]) = 0 (second and fourth term) or (I 3 −S abc [k−1]) = 0 (third term).…”

“…A similar argument holds true for the other terms if the lower controllable switch is turned on and/or the current direction is negative. To sum up: The first term in (9) corresponds to the first line of Tab. II, the second term in (9) to the third line of Tab.…”

“…To sum up: The first term in (9) corresponds to the first line of Tab. II, the second term in (9) to the third line of Tab. II, the third term in (9) to the second line of Tab.II and the fourth term in (9) to the fourth line of Tab.…”