Preliminary information
All Voltage Values
| Parameter | Min | Typ. | Max | Comment |
|---|---|---|---|---|
| Supply voltage | 11.5 V | 12 V | 13.2 V | Barrel Plug input, 2.1mm I.D. x 5.5mm O.D. Positive Centre |
| Input Current (Vin =12.0 V) | ||||
| HV enable (S1) off | 24 mA | |||
| HV enable on, Set point 0V, Output High | 60 mA | |||
| HV enable on, Set point FS, Output High, no Load | 220 mA | |||
| Output current | 80 uA | |||
| Voltage Calibration | ||||
| HV monitor @ DCDC converter, mean error | 0.08% FS | Over the whole voltage range | ||
| HV monitor @ DCDC converter, max error | 0.25% FS | Over the whole voltage range | ||
| HV monitor @ HVPS output, mean error | 0.15% FS | Over the whole voltage range | ||
| HV monitor @ HVPS output, max error | 0.55% FS | Over the whole voltage range | ||
| PID rise time | ||||
| Step from 0 to 10% FS | 30 ms | Kp=0.08, Ki=0.008, Kd=0 | ||
| Step from 0 to 100% FS | 90 ms | Kp=0.08, Ki=0.008, Kd=0 |
High voltage level control
- Open loop with a set point between 0 and 1000 representing 0-100% of full-scale output
- Regulated output with a set point resolution of 0.1% full scale. PID regulator control with user-settable Kp, Ki, and Kd values. PID controller updated every 1 ms.
High voltage reading
- 12-bit ADC high-voltage reading at the output of the High-voltage DC/DC converter used for output-voltage regulation
- 11-bit ADC high-voltage reading at the output connector for feedback to the user.
- 2 x 1000 samples / second
- Calibration of ADC voltage reading:
- Linear calibration
- Quadratic calibration
- Linear interpolation with a 21-points look-up table.
Output stage control
- Programmatically settable to 3 states:
- Output LOW: HV output connector connected to GND
- Output HIGH: HV output connector connected to the the High voltage
- Output OFF: Both optocouplers off. HV output connector connected to GND through the voltage reading circuit (100M impedance), which will discharge residual charges in an electrostatic actuator in ~0.1 s (for a 1nF load).
- Timer-controlled switching between the High voltage set-point and ground
- Minimum Frequency: 10 mHz (period of 100 s)
- Maximum Frequency: load-dependent (output current of hvps-x: 100-150 uA)
- User-settable duty cycle between 0% and 1% with 0.1% resolution.
- Manual control via on-board button
- latching or non-latching operation
Memory
Configuration and Operational parameters stored in device EEPROM, allowing quick start-up in a predefined configuration
Communication
Serial interface via usb-micro connector
4 kV unit
Regulation and Calibration accuracy
In closed-loop regulated voltage control
- Top: measurement as a function of the internal voltage set point.
- V output: Effective output voltage measured externally with a TESTEC HVP-15F 10kV probe.
- V hvps-x EM+: Calibrated voltage read internally and measured at the output of the High voltage DC/DC converter. This voltage is used as measurement for the closed-loop control of the output voltage.
- V hvps-x EM+: Calibrated voltage read internally and measured at the output connector of the hvps-x (after the optocouplers). Used to inform the user of the effective output voltage.
- Centre: Calibration error related to the internal measurement at the output of the DC/DC converter.
- Regulation error: Represents the error between the voltage set point and the internal voltage read by the hvps-x. It represents how well the PID regulator is working at keeping the output to the desired value.
- Calibration error: Represents the error between the voltage read internally by the hvps-x, and the actual output voltage measured externally with a TESTEC HVP-15F 10kV probe. It represents the precision of the calibration of the hvps-x.
PID regulation speed and profile
For kp=8E-2, ki=8E-3, and Kd=0. Curves measured at 20%, 40%, 60%, 80%, and 100% of full scale voltage. Measured externally with a TESTEC HVP-15F 10kV probe.
Switching profile
Square signal generated with the optocouplers at 100% of full scale. Measured externally with a TESTEC HVP-15F 10kV probe.
