PFC2400W375 Regulated Power Supply

Cost Savings

Depending on the cost of your electrical service, the severity of the problem, and how much you run your machine, a PFC power supply can pay for itself anywhere from 6 months to 3 years. After this the savings continue in perpetuity. Actual savings can be higher when the hidden costs of increased failure rates and down time are also considered.

In farmed applications where 10’s or 100’s of machines are installed in the same building, the AC waveform can degrade to the point where power distribution becomes inefficient.

In severe cases without power factor correction, the AC service rating has to be upgraded along with the wiring within the facility to meet the additional demand caused by the reactive components of the loads. Otherwise, the facility’s utility service and/or its wiring system have to be de-rated to carry the added reactive load. De-rating means the wires can’t carry the rated load, so to compensate, either a heavier gauge wire needs to be used or fewer machines can be installed.

In this example costs are increased due to the capital expense of upgrading the service and/or wiring, or by reducing the facility’s capacity (an opportunity cost), as well as increasing the electric bill along with fines associated with reactive demand because more power is needed to run the machines. If the distorted line harmonics spread out beyond the service entry to the building, then the utility provider may also charge additional penalties in various tiers depending on the extent of the violations.

One way to bring the power factor closer to the ideal value of 1 is to use power factor correction power supplies on every machine. The advantage of PFC power supplies over centralized PFC controllers is that the power supplies are inherently scalable – every time you add a machine, it already comes with its own built-in power factor correction. Another advantage for installing PFC correction on each machine is that the correction goes all the way up to the plug, whereas centralized PFC correction only corrects the power up-stream. The difference being installation at each machine provides total protection whereas a centralized solution leaves the possibility that the equipment sharing the same line can still victimize each other with line harmonics that negatively affect their operation and even increase failure rates.

Specialized for servos – ADVANCED Motion Controls PFC power supplies are designed to work specifically with servo drives.

Typical regulated power supplies and servo drives don’t work well together. The reason is the dynamic nature of servo drives can cause the current demand to change faster than the power supply can respond. The result is two closed loop systems that run against each other (out of phase with each other). Oscillations and instability results when the power supply tries to regulate the voltage from a rapidly changing load and the servo drive tries to regulate the motor while simultaneously compensating for the resulting fluctuations from the power supply – in essence the way they respond to each other feeds back on itself.

For those that are mathematically inclined, the system can be modeled as a non-ideal voltage source feeding a negative impedance (constant power) load. The solution produces a complex conjugate pair of poles which indicates underdamped behavior leading to oscillations and even instability depending on the circuit parameters. However, there’s a solution, the PFC power supplies from AMC don’t have this issue and are designed to supply a stable source of power regardless of the demand from the load, even in case of 100% load transients, in or out.

Another challenge for power supplies is that servo drives frequently regenerate energy back to the supply during certain events such as heavy deceleration. Many switching supplies can’t handle regeneration and have no way to prevent the bus voltage from rising to the point where either the servo drive shuts down due to over voltage or the power supply is damaged. The ADVANCED Motion Controls PFC power supply on the other hand can handle regenerative energy because it has a built-in shunt circuit. The circuit protects the servo drive and the power supply by directing excess energy through a resister preventing overvoltage issues from ever happening.

Custom solutions for specific applications

Custom power supplies that match specified loads and voltage levels are available for qualified applications. The advantage is the power rating can be sized to your needs and the power factor correction can be tuned for your load profile resulting in maximum efficiency and cost savings.

Another option is to have the PFC capabilities built into the servo drive in a complete custom solution. For OEMs the advantage here is that the drive will always receive the same clean power regardless of the local utility service or line quality thus ensuring consistent and reliable operation for your end-users.

Summary

• Clean consistent power anywhere in the world
• Designed specifically to work with servo drives and motor controllers
• Perfect for sensitive applications such as semiconductor, instrumentation, CMM and more
• Electrically, the PFC acts as a pure resistive load with a PF > 0.99
• Not affected by harmonic distortion, line voltage notching, effects from adjacent AC machines, line surge, line sag, even a skipped half-cycle
• Higher power, efficiency and reliability are expected from the drives feeding from the PFC
• Can pay for itself anywhere from 6 months to 3 years based on savings from utility costs and penalties

Product Highlights

• AC Line Harmonic Independent Power Factor Correction
• Line Voltage Surge and Lightning Protection
• High Efficiency and Power Factor even at Low Line and Loads
• Fault Status Logic Output for Power Sequencing
• AC Line Voltage and Frequency Monitoring and Protection
• Automatic and Forced Shunt Resistor Switch
• Soft Start Pre-charging Circuitry to Limit the Inrush Current
• Over Voltage, Over Current, Over Temperature Protections
• Medical Grade I/O Isolation and Chassis Leakage Current Rating
• Double Line Fused for Split Single-Phase Services
• Filtered Auxiliary AC Outlet for Ancillary System Loads

Input Specs

• 100 - 240 VAC Nominal AC Input Range
• 50/60 Hz Single Phase AC

Output Specs

• 375 VDC Output Voltage
• 3.2ADC continuous output current (@120VAC)
• 6.4ADC continuous output current (@240VAC)

Power and Efficiency

• 2.4kW @240VAC Input
• 1.2kW @120VAC Input
• >.95 Power Factor @250W up to .99 >250W
• 97% Efficiency @240VAC/50Hz