Circuit Diagrams Perfect Harmony Gen IV - part 2

Transformer Cabinet Power Cell Cabinet Fused Pre-charge Control Cabinet Water Management Unit Output Cabinet Input Cabinet

Circuit Diagrams Perfect Harmony Gen IV - part 1

(1) MCB Control Power (2) FF Latching Relay (3) Control Power Adaptation (4) Control Rack (5) Signal Conditioning Board (6) Break Out Board (7) Wago (8) PT100 Temp. Evaluation (9) Control Power Filter

Electronic Power Devices

- Semiconductor modules and resistors on support plates are extremely sensitive to mechanical stress risk of breaking the ceramic insulation - Place the module onto the heat sink in correct position - Note the sequence of tightening the screws according to the type of module; initially use a very moderate torque to fix the module - Again observing the sequence of tightening the screws tighten them using the advised torque (refer to the given table)

Personal Safety with Medium Voltage Drives

- Always follow proper lock-out / tag-out procedures (lock-out / try-out) before beginning any maintenance or troubleshooting work on the drive. According to local regulations, an “Energized Work Permit” may be required. - Work with one hand, turn away, keep a distance. - Wear insulated or rubber safety shoes. - Wear safety glasses and hearing protection. - Use appropriate equipment for checking low voltage, medium voltage - Voltages may drive a current through your body.

Motor Theory and Control Loops

- About 60% of the electricity generated is consumed by motors (in the US this equates to 1000 billion kilowatt hours, worth $50 billion US). - 92% of all power consumed by motors goes to induction motors. - A typical induction motor will consume 10 to 20 times its capital cost in energy per year. - Any technology, like VFDs, that helps conserve energy is economically important.

Perfect Harmony Pre-Charging

The internal resistance of discharged capacitors reads zero Ohms; as caps are charged, their resistance increases. To avoid the initial peak of the charging current and the oscillating voltage overshoot, voltage must not be applied “step-like” to the caps (preventing a “cell inrush”). For drives using cells with electrolytic capacitors (e.g. Gen IV) the pre-charging is effected by the sufficiently slowed down rise of voltage on the cell inputs (caused by the magnetization of the transformer).

Power Topology for the Perfect Harmony Drive

A power device that controls the speed of an AC motor by taking a fixed frequency, fixed AC input voltage and changing it into a variable AC frequency at a variable AC voltage. VFDs: - control standard AC Induction and Synchronous motors - maintain base-speed performance at varying speeds - replace more expensive variable speed equipment (e.g. DC drives, clutches, valves) - reduce maintenance costs - are more energy efficient (reduce operating costs; payback 1…2 years)