Caterpillar Inc.

Jyothiraditya Ramaswamy

Karthik Desingu

Jackson Wai

Ahmed Khalil

Gregory J Speckhart

James David Siegle

Yingying Kuai

Jean Marcos Lobo Da Fonseca

Gholamreza Esmaili

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

A fundamental harmonic matching control technique (FHMT) can optimize the use of the switching devices needed to operate a dual active bridge DC/DC converter, which reduces the peak and RMS currents thereby reducing the switching power losses. The FHMT control techniques can also reduce the current rating of the switching devices, transformer, and the inductor of the dual active bridge DC/DC converter.

Current control techniques for DC/DC converter

Growing community of inventors

Anupuram, India

Jyothiraditya Ramaswamy