Permanent Magnet Synchronous Machine (PMSM) and Ideal (continuous) Drive circuit, with mechanical load. The drive includes a D-Q control algorithm.

In a companion version of this design, "PMSM Motor And PWM Drive", the same motor control algorithm is used but SVM (space vector modulation) provides PWM switching signals to ideal switches in an actual 3-phase inverter implementation.

Permanent Magnet Synchronous Machine (PMSM) and PWM Drive circuit, with mechanical load. The drive includes a D-Q control algorithm, and uses space-vector modulation (SVM) to generate the digital PWM signals to the switches of the bridge.

The waveform plot in the upper left shows the drive command (light blue waveform), with values 0 to 1, where 1 is commanding the maximum quadrature current of 10 A. The motor's response is the output shaft angle in radians (orange waveform), and shows that increasing torque command results in greater rotational displacement against the load spring. The waveform plot in the upper right shows the actual motor torque (green waveform) and the A-phase current (dark blue waveform).

In a companion version of this design, "PMSM Motor And Ideal Drive", Clarke and Park Transform models are used with a continuous ideal voltage drive.This shows the ability to develop motor control and drives at the abstract level and at the circuit level.

In yet another version of this design example, the ideal switches will be replaced with actual power MOSFET device models. This can help in bridge component sizing and performance specification.

This example shows a more detailed circuit- and logic-level implementation of the PID Control Loop shown in the companion example, “PID Speed Control Loop – Continuous”. The ideal motor drive block of the “Continuous” version is expanded here, to include both a H-bridge motor drive, and also the digital logic necessary for converting the continuous PID controller output into the desired PWM signals that are distributed to drive the gates of the power MOSFET switches. The MOSFET model was calibrated to represent an IRF3710, using only information published on the manufacturer’s datasheet.

The rest of the system, including the PID block-diagram controller, the mechanical fan load and the DC Motor characterized to represent an FRC (First Robotics Competition) CIM Motor, are the same as in the Continuous version. While the simulation time for this switching version is significantly longer, more detailed information about practical circuit performance and component sizing is available. For example, the fan speed step response is somewhat different from the conceptual design, because of the losses in the MOSFETs under high current conditions, as well as voltage drop in the battery. Also, information regarding component stress levels within the “datasheet specified” MOSFETs and Diodes is provided.

Simple RC filter to transform PWM signal into an analog one

This example shows a more detailed circuit- and logic-level implementation of the PID Control Loop shown in the companion example, “PID Speed Control Loop – Continuous”. The ideal motor drive block of the “Continuous” version is expanded here, to include both a H-bridge motor drive, and also the digital logic necessary for converting the continuous PID controller output into the desired PWM signals that are distributed to drive the gates of the power MOSFET switches. The MOSFET model was calibrated to represent an IRF3710, using only information published on the manufacturer’s datasheet.

The rest of the system, including the PID block-diagram controller, the mechanical fan load and the DC Motor characterized to represent an FRC (First Robotics Competition) CIM Motor, are the same as in the Continuous version. While the simulation time for this switching version is significantly longer, more detailed information about practical circuit performance and component sizing is available. For example, the fan speed step response is somewhat different from the conceptual design, because of the losses in the MOSFETs under high current conditions, as well as voltage drop in the battery. Also, information regarding component stress levels within the “datasheet specified” MOSFETs and Diodes is provided.

This example shows a more detailed circuit- and logic-level implementation of the PID Control Loop shown in the companion example, “PID Speed Control Loop – Continuous”. The ideal motor drive block of the “Continuous” version is expanded here, to include both a H-bridge motor drive, and also the digital logic necessary for converting the continuous PID controller output into the desired PWM signals that are distributed to drive the gates of the power MOSFET switches. The MOSFET model was calibrated to represent an IRF3710, using only information published on the manufacturer’s datasheet.

The rest of the system, including the PID block-diagram controller, the mechanical fan load and the DC Motor characterized to represent an FRC (First Robotics Competition) CIM Motor, are the same as in the Continuous version. While the simulation time for this switching version is significantly longer, more detailed information about practical circuit performance and component sizing is available. For example, the fan speed step response is somewhat different from the conceptual design, because of the losses in the MOSFETs under high current conditions, as well as voltage drop in the battery. Also, information regarding component stress levels within the “datasheet specified” MOSFETs and Diodes is provided.

Convert the GPIO PWM outputs to Gate(0 +5v) and CV(-2.5v to 2.5v) used by doepfer modular synths.

This example shows a more detailed circuit- and logic-level implementation of the PID Control Loop shown in the companion example, “PID Speed Control Loop – Continuous”. The ideal motor drive block of the “Continuous” version is expanded here, to include both a H-bridge motor drive, and also the digital logic necessary for converting the continuous PID controller output into the desired PWM signals that are distributed to drive the gates of the power MOSFET switches. The MOSFET model was calibrated to represent an IRF3710, using only information published on the manufacturer’s datasheet.

The rest of the system, including the PID block-diagram controller, the mechanical fan load and the DC Motor characterized to represent an FRC (First Robotics Competition) CIM Motor, are the same as in the Continuous version. While the simulation time for this switching version is significantly longer, more detailed information about practical circuit performance and component sizing is available. For example, the fan speed step response is somewhat different from the conceptual design, because of the losses in the MOSFETs under high current conditions, as well as voltage drop in the battery. Also, information regarding component stress levels within the “datasheet specified” MOSFETs and Diodes is provided.

This example shows a more detailed circuit- and logic-level implementation of the PID Control Loop shown in the companion example, “PID Speed Control Loop – Continuous”. The ideal motor drive block of the “Continuous” version is expanded here, to include both a H-bridge motor drive, and also the digital logic necessary for converting the continuous PID controller output into the desired PWM signals that are distributed to drive the gates of the power MOSFET switches. The MOSFET model was calibrated to represent an IRF3710, using only information published on the manufacturer’s datasheet.

The rest of the system, including the PID block-diagram controller, the mechanical fan load and the DC Motor characterized to represent an FRC (First Robotics Competition) CIM Motor, are the same as in the Continuous version. While the simulation time for this switching version is significantly longer, more detailed information about practical circuit performance and component sizing is available. For example, the fan speed step response is somewhat different from the conceptual design, because of the losses in the MOSFETs under high current conditions, as well as voltage drop in the battery. Also, information regarding component stress levels within the “datasheet specified” MOSFETs and Diodes is provided.

The AS123 LED Driver from ACME Semiconductor (fictional) provides fully integrated PWM dimming and a programmable current set-point. This IC is specifically for automotive rear combination (tail/stop) lighting applications. It tightly regulates the desired string current under conditions of widely varying applied DC voltage.

The PWM dimming function, which switches the LED on and off at just over 300 Hz, is active when the line input pin is high and the "PWM_disable" pin is low (

The AS123 supports current programming using a single external resistor (see r_iset in the schematic). The resistor value can be selected to give the desired LED string current, using the following formula:

r_iset = 1.85/i_desired

The AS123 is capable of regulating up to 100mA per string continuously. Therefore the value of r_iset should be no less than 18.5 Ohms. The user can change this resistor value and run a new simulation, to see the effect of this change on the LED string current.

See a "functional block diagram" schematic model of the ACME AS123 here: https://www.systemvision.com/design/acme-as123-led-driver-schematic-model

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