Caterpillar Inc.

Karthik Desingu

Jyothiraditya Ramaswamy

Jackson Wai

Ahmed Khalil

Gregory J Speckhart

James David Siegle

Jean Marcos Lobo Da Fonseca

Capacitor voltage balancing techniques are described for a 3-level 3-level dual-active-bridge converter that controls the duration of a zero voltage state of the low voltage (LV) and medium (MV) side transformer voltages based on a voltage difference between the upper and lower capacitors of both the LV and MV sides independently, the power delivered (P), and the LV and MV DC voltages. This control varies the angle to maintain the power requirement, which induces the additional voltage drop across the transformer inductance to produce the required current to flow through the capacitors and balance the capacitor voltages.

Capacitor voltage balancing techniques for multi-level dual active bridge converter

Techniques are described to smooth start a multilevel dual active bridge converter by pre-charging the capacitors present on the converter without requiring any additional hardware. Various phase shift angles determine the power delivered by the dual active bridge converter. By using the techniques, a predefined amount of time is reserved to pre-charge the capacitors until the capacitors reach a desired voltage after which time the smooth starting of the dual active bridge converter is initiated.

Start-up control for multilevel dual active bridge converter

Growing community of inventors

Puducherry, India

Karthik Desingu