Capable of sourcing and sinking power, BOP Power Supplies produce 1,000 W of dc power bi-directionally in 6 models from [+ or -]10 to [+ or -]100 V. Units pass smoothly through zero to provide true [+ or -] voltage and [+ or -] current. To maintain low dissipation while sinking power from active load, devices recuperate energy for reuse. Power supplies can be controlled digitally from front panel keypad, as well as GPIB or RS-232 remote interfaces to set voltage or current and 4 protection limits.
Kepco's bipolar models, called BOP, are capable of four-quadrant operation, meaning that they can swing from plus to minus voltage and plus to minus current. When they are set to produce a plus voltage and a plus current, or a minus voltage and a minus current, the BOP are conventional sources. When operation requires a plus voltage and a minus current, or vice versa, then the BOP are absorbing power from its load and are acting as a sink. As the 1000 watt BOP are high-efficiency switch mode designs, they dispose of the power they sink in a non-dissipative fashion by recuperating it back to the a-c power mains.
Bipolar power supplies are often used to simulate phenomena that are polarity or direction-sensitive: right-left, clockwise-counterclockwise, charge-discharge. They can simulate the day-night cycle of battery charging, the right-left torque of power steering assemblies and can control motors, electron beams and steering magnets.
BOP are used to produce all sorts of d-c to medium frequency output variations and waveforms. These can be programmed by analog input or by SCPI-based digital control through either IEEE 488-2, RS 232 or RS 485 (bitbus, IEEE 1118). Additionally, there is direct entry output control through the panel-mounted keypad. The newly introduced internal waveform generator allows a user to combine segments of a sinusoidal waveform, triangular waveform, a ramp, a sawtooth waveform and a square 50% duty cycle pulse, plus d-c to create a variety of arbitrary waveforms. 3,933 of points per basic waveform can be programmed with arbitrary, phase relationships. The resulting waveshape can be repeated from 1 to 255 times. For count 0, the waveshape is executed indefinitely until a stop command is received. The waveshape graphics are displayed on a panel-mounted LCD display, which also displays both settings and actual output values.
The programmed waveshapes can be used to control either voltage or current with both positive and negative values. Voltage mode bandwidth is d-c to 2 KHz. Current mode bandwidth is d-c to 0.8 KHz. Thus, for example, it is possible to reproduce an a-c sinusoid with differing degrees of distortion or drop outs for test purposes. Alternatively varying amounts of "noise" can be added to a d-c output to gauge the effect on a test subject. With the built-in arbitrary waveform generator, much more complex waveforms can be made to drive these kilowatt-sized power amplifiers to do test and simulation work.
For even higher power, the 1000 watt BOP models can be combined in serial and parallel combinations. For example up to three models can be connected in parallel in a master-slave configuration so that their output currents track and add to produce 3000 watts of d-c to low frequency waveforms. It is readily possible to connect two sets of three-in-parallel BOP power supplies to produce a fully programmable 6KW combination. It is also possible to place three units in series and parallel connect two of these groups to obtain the same 6KW. The instruction manual provided with the instruments provides illustrated instruction on how they may be interconnected to add voltage or add current.
More information is available on the Kepco website, www.kepcopower.com.
The BOP High Power are true 4-quadrant programmable voltage and current power supplies. 4-quadrant operation means that they are capable of both sourcing and sinking power. These bipolar power supplies pass smoothly through zero to provide true [+ or -] voltage and [+ or -] current. The BOP High Power use switch mode technology for low dissipation. To maintain low dissipation while sinking power from an active load, the BOP High Power recuperate the energy for reuse. The key to this is a bi-directional a-c input power factor correcting (PFC) circuit, which allows transparent energy interchange without dissipative sinking. The PFC circuit lowers the line harmonic distortion of the input current while maintaining a power factor greater than 0.97. The PFC works in both generation and recuperation modes.
The BOP High Power models produce 1000 watts of d-c power bi-directionally in six models from [+ or -]10V to [+ or -]100V.
The BOP High Power models are controlled digitally from a front panel keypad or either of the built-in standard remote interfaces, either GPIB or RS 232, to set voltage or current and the four protection limits (+voltage, -voltage, +current and -current). A large LCD displays the settings, mode of operation and the actual output voltage and current. Additionally, the BOP High Power can be remotely controlled by an analog [+ or -]10V input. This mode is selected by the keypad from the menu, or remotely, through the IEEE 488 controller.