TeraDiode (United States)

High Power Diode Laser Bars serve as the foundation for many high-power laser systems used in manufacturing and research. Efficient heat removal is essential for reducing cost per watt by increasing available output power or extending the effective lifetime of these devices. In this paper we will introduce a novel method for electrically isolated water impingement cooling of high-power diode laser bars operating in the 975nm region. We will present results from 58 emitter diode laser bars operating in the 975nm region with CW output power levels exceeding 500W and a thermal resistivity of less than 0.12 K/W.

Low generational inertia and lack of damping elements cause stability concerns in dc microgrids. Power buffers have been introduced to damp volatile load demands and improve microgrid's stability. Power buffer is a power electronics converter with large storage components (e.g., capacitors), which can decouple dynamics of a power distribution network and electronic loads by adjusting its input impedance and stored energy. Typically, power buffers are controlled individually to serve local loads. Alternatively, collective operation of power buffers is considered here to extend their damping effect to neighboring loads. Additionally, the group operation allows buffer designs with smaller storage components. A supervisory control to manage energy-impedance profiles of power buffers across a grid would require a complex communication network. Alternatively, distributed control lays a reliable ground to link power buffers with a minimal communication. This work offers a fully distributed feedback control algorithm to collectively manage the power buffers, using a sparse communication network. The controller enables the buffers to collectively respond to any load transient. Hardware-in-the-Loop simulation of a dc microgrid is used to show the controller's efficacy; it successfully groups power buffers in the neighborhood of the affected load and manages their energy reservoirs to shape the power supplied by the grid.

This chapter discusses the advanced methods for distributed control of AC microgrids. First, a two-layer control framework that implements the secondary control for an islanded microgrid containing both VCVSIs and CCVSIs is discussed. The first control layer deals with the voltage and frequency control of VCVSIs. The second control layer objectives are to control the active and reactive powers of CCVSIs. Each control layer is implemented through the distributed control of multi-agent systems. Then, a distributed and adaptive secondary voltage control method is discussed. The proposed controller compensates for the nonlinear and uncertain dynamics of DGs and, hence, obviates the control design challenges caused by the nonlinear dynamics of DGs. The controller is fully independent of the DG parameters. Therefore, the controller can be deployed on any DG regardless of the DG parameters and the connector specifications, and its performance does not deteriorate by the change in DG parameters (e.g., due to aging and thermal effects). The discussed controller appropriately responds to the changes in the system operating condition, without any manual intervention, and adjusts its control parameters in real time.

TeraDiode has built kW-class direct diode lasers with the same output power and beam quality as existing industrial lasers. Our kW-class direct diode laser has cut gauge-thickness metal with comparable quality as existing industrial lasers.