1 / 11

Protection Systems

Protection Systems. Batteries and Protection Systems Session Daniel Bohachick. Protection System Topics. System overview Fail safe concerns Reliability Real world behavior Whole system protection Implementation. System Overview. Primarily to protect batteries

orenda
Download Presentation

Protection Systems

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Protection Systems Batteries and Protection Systems Session Daniel Bohachick ASC2005 Kickoff Conference

  2. Protection System Topics • System overview • Fail safe concerns • Reliability • Real world behavior • Whole system protection • Implementation ASC2005 Kickoff Conference

  3. System Overview • Primarily to protect batteries • Operates whether sourcing or sinking power • Complete Electrical Isolation from other Systems • Automatic monitoring and reaction • “Smart Fuse” • No single correct solution 5.8.3. Protection Circuitry – Batteries must have protection circuitry appropriate for the battery technology. Proof is required at scrutineering that the protection system is adequate. Protection circuitry should be primarily for the purpose of protection. ASC2005 Kickoff Conference

  4. System Overview(cont.) Array Protection System Battery Pack Power Trackers Power Switch(es) Motor Motor Controller ASC2005 Kickoff Conference

  5. Fail Safe Concerns • The Culprits • Incorrect setting on power trackers or motor controller • Lack of active monitoring(telemetry or driver readouts) • Regen Braking • What occurs when a fault is detected • Actions afterward Protection System Limits* 1) Over Voltage(OV) 2) Over Temperature(OT) 3) Over Current(OC) 4) Under Voltage(UV) * Depending on Battery Chemistry ASC2005 Kickoff Conference

  6. System Overview(cont.) Array Protection System Battery Pack Power Trackers Power Switch(es) Motor Motor Controller ASC2005 Kickoff Conference

  7. Reliability • Verifying Set Points • Diagnostics and Fault Readout • How is protection system powered? • Sensitivity to noise(EMI/RFI) • Sense Voltage Isolation(Galvanic, Optocouplers) • Ability to impound(connectors, sense leads) • Hysteresis, Delay, Calibration ASC2005 Kickoff Conference

  8. Real World Behavior • In-house or off the shelf designs do not always work according to spec • Power tracker and motor controller set points can be changed • Human error • Secondary system damage • Motor Controller ASC2005 Kickoff Conference

  9. Whole System Protection • Regen on a steep down hill can cause problems due to a battery fault conditions isolating the motors load causing a large dI/dT for the inductance and since V = L dI/dT, then a large transient voltage could appear on the motor controller bus causing damage to: • MOSFET • Main Capacitor • Internal DC/DC • Motor Winding I **Also some MPPT should be shut off before battery is disconnected. ASC2005 Kickoff Conference

  10. System Overview(cont.) Array Protection System Battery Pack Sequenced Power Shut Down Power Trackers Power Switch(es) Motor Motor Controller Dynamic Braking ASC2005 Kickoff Conference

  11. Implementation • Braking Resistor, Clamping Diode, or Transient Stability Circuit on Main Bus. • Integrate Protection System to soft shut down all sources • Provide telemetry to detect and prevent conditions that result in faults • When a fault occurs determine root cause before continuing • Understand effects on system when an abrupt shut down occurs ASC2005 Kickoff Conference

More Related