Bidirectional dc-dc converters (BDC) have recently received a lot of attention due to the increasing need to systems with the capability of bidirectional energy transfer between two dc buses. Apart from traditional application in dc motor drives, new applications of BDC include energy storage in renewable energy systems, fuel cell energy systems, hybrid electric vehicles (HEV) and uninterruptible power supplies (UPS).
The PSB 9000 Series is a bidirectional DC source that incorporates two devices in one: a power supply (source) and an electronic load (sink) with energy recovery. The PSB 9000 Series has the functionality of two-quadrants operation as a standard. In source mode, the device becomes a flexible, auto-ranging power supply like our PSI 9000 Series. In sink mode, the device acts like an electronic load with an energy recovery feature, such as our ELR 9000. The PSB 9000 eliminates the need for two topologies, chassis and reduces space, weight, and cost.
Key Features of the PSB 9000 series Auto-Ranging DC programmable power supply:
Up to 95.5%
With Automatic Detection
Temperature Controlled Fan Speeds
Auto-Ranging Output Stage
With Pushbuttons & Blue LCD for Actual Values, Set Values, Status & Alarms
USB & Ethernet Port Integrated or alternatively Installed IEEE/GPIB Port
SCPI Command Language Supported
As the name “bidirectional” implies, there are basically two modes of operation in an “Integrated Bidirectional DC” converter in terms of power transfer. These modes are denoted by Mode A-to- B and Mode B-to- A. Some correlate this feather as “charging” and “discharging” modes, which comes from the fact that at least one of the dc sources in many IBDC applications is a battery, and thus charging and discharging terms become meaningful. The PSB is ideally suited to test batteries, EV chargers, Motor Controllers and Energy Storage Systems.
Auto-Ranging Power Stage
All models are equipped with a flexible auto-ranging bi-directional power stage which provides a higher output voltage at lower output current, or a higher output current at lower output voltage, always limited to the max. nominal output power. The power set value is adjustable with these models. Therefore, a wide range of applications can already be covered using just one unit.
Much like our ELR 9000 Series of Programmable DC Loads, the PSB 9000 regenerates 92-94% of the sunk current to the AC input. This form of energy recovery lowers energy costs, heat dissipation and avoids expensive liquid cooling systems, as required conventional electronic loads which convert the DC input energy into heat.
All models within this series include a true function generator which can generate typical functions, as displayed in the figure below, and apply them to either the output voltage or the output current. The generator can be completely configured and controlled by using the touch panel on the front of the device, or by remote control via one of the digital interfaces. The predefined functions offer all necessary parameters to the user, such as Y offset, time/frequency or amplitude, for full configuration ability. Additionally, to the standard functions which are all based upon an arbitrary generator, this base generator is accessible for the creation and execution of complex sets of functions, separated into up to 99 sequence points.
Accurately testing batteries using a standard Electronic Programmable Load or DC source can create challenges. Batteries respond to change in current demand in mico-seconds (µsec), while most programmable devices respond in milli-seconds (msec). In sink mode of operation (load), the PSB slews from 10% to 90% of full scale current in <50µsec. The PSB 9000’s high speed slew rates results in real-world simulation since speeds are similar to that of an actual battery.