Application Note
78F0714
8-Bit Single-Chip Microcontroller
Permanent Magnet Synchronous Motor Control
µPD78F0714
Document No. U19166EE1V0AN00
Date published February 2008
© NEC Electronics 2008
Printed in Germany
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Application Note U19166EE1V0AN00
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Application Note U19166EE1V0AN00
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4
Application Note U19166EE1V0AN00
Table of Contents
Chapter 1
Introduction
.......................................................
6
Chapter 2
Working System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7
2.1
System Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2
Development Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2.1
In-Circuit Emulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2.2
Integrated Development Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3
Source Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.1
Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.2
File Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 3
PMSM Motor Fundamentals
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1
Target Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2
Sine PWM Digital Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3
Synchronization with Hall Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.4
Close Loop Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.5
System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Chapter 4
Getting Started
Chapter 5
Software Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
21
5.1
Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.2
Program Area Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Chapter 6
Sample Result
Chapter 7
Source Code
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1
Marco Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.2
Global Variable Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.3
Main Entry Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.4
System Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
7.5
Main Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.6
Hall Sensor Signals Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.7
PI Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Application Note U19166EE1V0AN00
5
Chapter 1 Introduction
This application note presents a 3-phase permanent magnet synchronous motor
control software developed for NEC 8-bit microcontroller uPD78F0714 with
sinusoidal waveform. The 78F0714 microcontroller facilitates a dedicated
peripheral for 3-phase motor control, enabling easier motor drive with AC
induction motors and/or permanent magnet DC/AC motors (BLDC/PMAC).
The presented software library is written in standard C language and provides a
set of sample functions for sinusoidal waveform generation, the synchronization
mechanism and closed loop control of PMSM drive. The source code is
compatible with IAR (http://www.iar.com/) Embedded Workbench C/C++
compiler and debugger tools.
This software library can be taken as a demonstration tool together with NEC
Motor Control Starter Kit (MC-LVKIT) and a Maxon EC motor. By using the sine
wave generation and speed regulation algorithms provided in the library, user can
concentrate on the application development with a few parameter adaption.
A PMSM usually consists of a magnetic rotor and wound stator. The magnetic
rotor rotates as the magnetic field produced by the wound stator changes. Such
construction requires no brushes in between, producing greater efficiency and
power density. It provides high torque-to-inertia ratios and also reduces the
maintenance cost. A PMSM generates magnetic flux using permanent magnets
on the rotor, which generates torque most effectively when it is perpendicular to
flux generated by the stators. To maintain near-perpendicularity between stator
flux and rotor flux, a control method with position-speed feedback loop are
popularly used for controlling a PMSM.
Prerequisite
Note
Disclaimer
6
The prerequisite for using this library is the basic knowledge of C programming,
AC motor drives and power inverter hardware. In-depth know-how of motor
control functions is only required for customizing existing modules and when
adding new ones for complete application development.
This control software only functions with NEC Library for Motor Control in the
preliminary version.
The demo control software described in this application note is used for
demostration purpose only. Please do not use it for any purpose beside
demostration and evaluation purpose.
Application Note U19166EE1V0AN00
Chapter 2 Working System
2.1 System Feature
•
•
•
•
The motor control algorithm employs PI closed-loop control. The
power switches are controlled by means of sinusoidal pulse width
modulation (PWM).
The rotor position feedback hardware elements are Hall sensors.
The motor is capable of rotating in both direction and has a speed
range from 500 rpm to 9000 rpm.
Rotation direction, control profile, speed and current overshoot can
be controlled with help of NEC Motor Control Visualizing GUI.
2.2 Development Tools
2.2.1 In-Circuit Emulator
The user software can be downloaded to the target device with on-chip
debugging (OCD) emulator NEC 78K0MINI, a separately sold device, which
supports pseudo real-time RAM monitoring and C-Spy debugging.
Figure 2-1
NEC MINICUBE Connection
For more information about this OCD emulator, please refer to document
U17029EJ3V0UM00.
Application Note U19166EE1V0AN00
7
Chapter 2
Working System
2.2.2 Integrated Development Environment
This library is compiled with C/C++ compilers and debuggers for NEC Electronics
78K0 of IAR Embedded Workbench 4.40 or higher version.
Note
You can download the 4K limited free version of IAR Embedded Workbench to
compile the software library.
2.3 Source Code
2.3.1 Downloads
The source code of this control software can be downloaded on http://
www.eu.necel.com/docuweb/
2.3.2 File Structure
Kernel Files
io78f0714.h
•
Microcontroller specific files, registers addresses
Ink78f0714.xcl
•
Microcontroller specific files, segment definition
definitions.h
•
Macro definitions
global.h
•
8
Global variables definitions
Application Note U19166EE1V0AN00
Working System
Main Programs
Chapter 2
pmsm_main.c
•
Entry program
init.h, init.c
•
Hardware initializing functions
mainfunctions.h, mainfunctions.c
•
•
•
•
Control Programs
Sine waveform output function
ADC measured data storage function
Current overshoot precaution function
Software variables reset function
Hall.h, Hall.c
•
Interrupt sub-routines for hall sensor signal change
regulation.h, regulation.c
•
PI controller function
NecLib.h, NecLib.c
•
NEC Library for Motor Control
Application Note U19166EE1V0AN00
9
Chapter 3 PMSM Motor Fundamentals
This chapter will explain the basic process of developing a control software for
PMSM.
3.1 Target Motor
PMSM
A PMSM rotates at a fixed speed in synchronization with the frequency of the
power source independent of the load, provided an adequate field current is
applied on the motor windings.
A 3-phase PMSM drive commutates the phase windings sinusoidally such that
the stator magnetic field is at 90 degrees to the PM rotor magnetic field, producing
a maximum torque on the rotor.
Figure 3-1
PMSM and BLDC
PM Motor Cross Section and Electromagnetism
By design, the basic architecture of a BLDC motor and a PMAC motor have no
intrinsic differences. A BLDC motor can normally be driven by alternating current
and PMAC motor by direct current. However, the windings are specially designed
to retain a trapezoid form of current for BLDC motor and a sinusoidal form for
PMAC motor.
BLDC motor
PMAC motor
Phase Voltage and Phase Current rectangular
sinusoidal
Current Peak Value
high
low
Torque
with commutation
ripples
smooth
Noise
high
low
Core Power Loss
high
low
Switching Power Loss
low in inverter
high in inverter
Implementation
simple
relatively complicated
In a BLDC motor, only two windings carry current at any given time. This reduces
the winding utility by 33%. On the other hand, in a three-phase PMAC motor,
three-phase sinusoidal voltages are applied on all three windings and all three
windings carry current at all times. This will naturally increase switching loss in
inverter.
10
Application Note U19166EE1V0AN00
PMSM Motor Fundamentals
PMSM Model
Chapter 3
Stator voltage differential equations:
RA, RB, RC are the resisitence in the stator
Stator and rotor flux linkages:
LAA, LBB, LCC are the stator inductances.
LAB, LAC, LBA, LBC, LCA, LCB are the mutual inductances.
Application Note U19166EE1V0AN00
11
Chapter 3
PMSM Motor Fundamentals
3.2 Sine PWM Digital Control
NEC 78F0714 8-bit micro-controller contains a 10-bit inverter control timer. This
timer consists of an 8-bit dead-time generation timer, and allows non-overlapping
active-level output, as in the figure depicted below.
Figure 3-5
Inverter Timer Outputs
A sinusoidal waveform can be represented by a number of relative values
compared to the triangular carrier signal. The frequency of the sinusoidal
waveform is dependent of the number of relative values within a period. The ratio
of sine wave peak value to triangular wave peak value determines the output
waveform amplitude.
To gain a precise control of output waveform amplitude, the maximum of relative
value (resolution) should be as large as possible. But higher resolution will lead to
lower PWM frequency. Frequencies of lower than 20KHz can produce noises
within human audible threshold. On the other hand, the faster the PWM frequency
is, the less time the MCU will have to execute commands. To minimize acoustic
disturbance while having more time for program routines, 20KHz is usually
selected as PWM cycle.
The NEC micro-controller 78F0714 works with a 20MHz oscillator. The compare
counter maximum (half of the PWM cycle) is thus 20MHz / 20 KHz / 2 = 500.
12
Application Note U19166EE1V0AN00
PMSM Motor Fundamentals
Chapter 3
The base frequency of a sine wave is dependent on the number of sampling
points. In other words, it depends on the size of the sine look-up table. Too few
sampling points will lead to a so-called staircase effect. The staircase effect will
cause excessive motor current distortion, which causes higher heat dissipation.
Superfluous sampling points consume precious memory in the micro-controller.
A good rule is to divide the PWM carrier frequency by the maximum desired sine
wave frequency. The nominal speed of the motor in case is around 10000 RPM,
corresponding to a sine wave frequency of 166.67Hz. The number of look-up table
sampling points is 120.
The generated PWMs are then transmitted to transistor switches of an inverter in
the control hardware. DC power will thus be converted to AC power at the required
frequency and amplitude.
Figure 3-6
Half-bridge Circuits and Motor Connection
The inverter is composed of three equivalent half-bridge circuits. Only one side
of the half-bridge circuit, either the high side or the low side, should be switched
on at any given time. Otherwise the control hardware will be short-circuited. Deadtime is then inserted to avoid such situation.
At the outputs of the half-bridge circuits, 120-degree-shifted three-phase
sinewave waveforms can be detected with a simple RC-circuit.
Figure 3-7
Sinusoidal Control Waveform and corresponding PWM Signals
The amplitude of the line-voltage is always less than that of the output waveform,
around 88.6% of the peak value. This effect is an intrinsic limitation of the sine
PWM control method.
Application Note U19166EE1V0AN00
13
Chapter 3
PMSM Motor Fundamentals
3.3 Synchronization with Hall Sensors
Determining Rotor
Position
Figure 3-8
14
Hall sensors are used to determine rotor position during operation. Using the builtin Hall sensors in phase winding can simplify control logic and does not require
extra circuit to process the signals. Electricity carried through the phase winding
conductor will produce a magnetic field that varies with current, and such a Hall
sensor can be used to measure the current without interrupting the circuit.
Rotor Position and Hall Sensors Outputs
Application Note U19166EE1V0AN00
PMSM Motor Fundamentals
Chapter 3
By connecting Hall sensor signals to microcontroller interrupt input pins, the
interrupt request will be generated when the signals change. The corresponding
subroutine can thus estimate the rotor position according to turing direction and
update the output waveform angle accordingly.
Table 3-1
Section allocation by Hall sensor signals combination
Hall C
Hall B
Hall A
Section
0
0
0
Invalid
0
0
1
1
0
1
0
3
0
1
1
2
1
0
0
5
1
0
1
6
1
1
0
4
1
1
1
Invalid
The sections are numbered according to the rotor position illustrated in Figure
3-5 .
The relationship between Hall sensor signals and the desired control signal
waveform can be depicted in the figure below by resorting the section orders.
Figure 3-9
Motor Currents and Hall Sensor Signals rotating clockwise
Application Note U19166EE1V0AN00
15
Chapter 3
PMSM Motor Fundamentals
3.4 Close Loop Control
Introduction
PI controller is a generic feedback controller commonly used to implement
closed-loop control. A PI controller responds to an error created by subtracting
desired value from output quantity. Then it adjusts the controlled quantity to
achieve the desired system response. The controlled value can be any
measurable system quantity such as speed, torque or flux. The parameters of a
PI controller can be adjusted empirically by tuning one or more gain values and
observing the change in system response. A digital PI controller is executed at a
periodic sampling interval. It is assumed that the controller is executed frequently
enough so that the system is under proper control.
The proportional (P) contribution of the controller results from multiplying the error
by a P gain value. A larger error results in larger proportional contribution. This P
term contribution tends to reduce the overall error as time elapses. However, the
P term has less effect as the error approaches zero. Most systems with P term
only controller have a steady error and do not converge. Large P gain value
imposes a tight control on the output value but an excessively large proportional
gain will lead to process instability.
The integral (I) contribution of the controller is used to eliminate small steady error
but always brings along larger overshoot. Errors of the system are multiplied by I
gain value and accumulated over time into an error buffer. This error buffer forms
the I term output of the PI controller.
Speed Measurement
A closed-loop PI speed controller requires actual motor speed for controller input
to eliminate the speed difference. The actual motor speed is in this software is
realized by computing the time elapsed between two consecutive Hall signal
changes.
Hall sensor C signal is connected to interrupt pin INTP5. Interrupt request will thus
be generated each time the Hall sensor C signal changes. 16-bit Timer Counter
01 is set to run at 78KHz and is read during this interrupt service. The timer counts
multiplying the Timer Counter 01 interval is the time elapsed since the last Hall
sensor signal change.
Figure 3-10
16
Speed Measurement with Hall Sensor C Signal
Application Note U19166EE1V0AN00
PMSM Motor Fundamentals
PI Controller
Figure 3-11
Chapter 3
The digital PI controller is called at fixed time interval by checking the overflow
flag of a dedicated timer counter.
PI Speed Controller Implementation
The speed difference is computed by subtracting actual motor speed from
setpoint. The difference will be multiplied by P-gain and I-gain factor. The sum of
the two gains will be normalized to duty cycle of the inverter timer to update the
output waveform amplitude.
The parameters of the PI controller can be determined by using the ZieglerNichols closed-loop tuning method.
Table 3-2
Ziegler-Nichols closed-loop parameter tuning method
Controller Type
P-Gain
Reset Time
P Controller
0,5 x Kc
-
PI Controller
0,45 x Kc
Kc / Tc
Kc is the critical value of P-gain factor, with which the P-only Controller results in
an ultimate periodic oscillation of output response.
Tc is the period of the oscillation.
Application Note U19166EE1V0AN00
17
Chapter 3
PMSM Motor Fundamentals
3.5 System Overview
The sensorred control system presented in this application note has the following
implementation:
Figure 3-12
Implementation of the control software
The setpoint of motor speed is specified with user input made on the NEC
Visualizing GUI for Motor Control.
The sine angle of the output waveform is updated on Hall sensor signal change
and the measured frequency fmotor will impose on the motor to keep it in
synchronization.
When the current in the motor overshoots the threshold value of the rectifier, an
interrupt request will be made to the microcontroller. The demo software will shut
off the MOSFET with a switch signal during the interrupt service.
18
Application Note U19166EE1V0AN00
PMSM Motor Fundamentals
Chapter 3
The control system has the following states
Figure 3-13
System States of the Control Software
When Stop command is sent to the control software, the motor will be stopped
even when the setpoint is not zero.
AD converter can be used to measure system variables such as motor shunt
current and phase currents. Such features are not implemented in the demo
software presented in this application note.
Application Note U19166EE1V0AN00
19
Chapter 4 Getting Started
To debug the user program, the NEC 78K0MINI in-circuit emulator (ICE) should
be connected with the micro board through the 2JP7 on-chip debugging
connector as shown in Figure .
Figure 4-1
MINICUBE Connection with NEC StarterKit for Motor Control
To debug software using desired working frequency, an external oscilltor must be
mounted on the ICE oscillator slot.
Figure 4-2
20
External Oscillator Installation
Application Note U19166EE1V0AN00
Chapter 5 Software Configuration
This chapter will describe the possibilities of enabling / disabling some features
implemented in the demo control software.
5.1 Control Registers
Some features implemented in this demo control software can be enabled or
disabled by manipulating the macro definitions in header file definitions.h in the
sample source code.
The major control variables are defined in the header file global.h. Possible values
of the control variables are described below.
definitions.h
ENABLE_UART
This macro definition enables UART communication.
To reduce flash memory consumption, user can disable UART communication,
by commenting out the definition.
CLOSE_LOOP
This macro definition indicates the compiler include the close loop control code.
To exclude closed-loop control function, user can comment out the definition.
SENSORRED
This macro definition indicates the compiler include the close loop control code.
To exclude this code, comment out the definition.
norm_constant
This constant is used to calculate the motor actual speed from timer counts.
actual_count_min, actual_count_max
These two constants are used to limit the timer count value. Value exceeding the
limit will be ignored.
global.h
onoff
This flag stores information of system on / off state.
0 = system stopped, 1 = system set to start, 2 system running
disconnx
This flag indicates if the motor system is disconnected from visualizing module.
0 = normal, 1 = system disconnected
OverCurrent
This flag indicates if motor current overshoot occurred.
0 = normal, 1 = motor current oveshot
Application Note U19166EE1V0AN00
21
Chapter 5
Software Configuration
Motor_Dir
This flag indicates the motor rotation direction.
0 = anti-clockwise, 1 = clockwise
Loop_Sel
This flag indicates the motor drive control method.
0 = open-loop, 1 =closed-loop
SecureSel
This flag indicates if hardware over-current protection is used.
0 = disabled, 1 = enabled
SensorSel
This flag indicates the motor drive synchronization method.
0 = sensored control, 1 = sensorless control
BemfA_sel, BemfB_sel, BemfC_sel
These three flags determine which channel of the Back-EMF should be measured
by A/D-Converter.
0 = not selected, 1 = selected.
ovf
This flag indicates the number of times the timer overflows.
After the third time of timer overflow, the motor speed will be set to 0, and system
will be stopped.
5.2 Program Area Consumption
By changing the macro definitions in the header file definitions.h, program size
of the demo software varies as shown in the table below.
Table 5-1
22
Program size with different settings
ROM Area
RAM Area
Close Loop with UART
3,820 bytes
446 bytes
Open Loop with UART
2,870 bytes
430 bytes
Close Loop without UART
2,787 bytes
248 bytes
Open Loop without UART
1,834 bytes
232 bytes
Application Note U19166EE1V0AN00
Chapter 6 Sample Result
This chapter will show some sample results using the control software described
in this application note.
Figure 6-1
Phase Voltage, Current and Hall Sensor Signal at 1272 rpm (21.19Hz)
Figure 6-2
Phase Voltage, Current and Hall Sensor Signal at 7428 rpm (123.8Hz)
Channel 1 depicts the motor phase current.
Channel 2 depicts the phase control signal waveform.
Channel 4 is the Hall sensor signal of the correspondent phase.
Application Note U19166EE1V0AN00
23
Chapter 6
Sample Result
The figures below display the system dynamics of the in-use PI speed controller
under different circumstances.
Figure 6-3
P-Gain-only Dynamic Performance with Kp varying from 0.03 to 0.146
Figure 6-4
PI Controller Dynamic Performance with Ki varying from 0 to 0,015
Figure 6-3 displays the system response with proportional error control.
Figure 6-4 displays the system response under a PI speed controller with different
settings of I-gain.
24
Application Note U19166EE1V0AN00
Chapter 7 Source Code
This chapter will list the source code of the demo control software described in
this application note.
7.1 Marco Definitions
#ifndef __DEFINITIONS_H__
#define __DEFINITIONS_H__
#include <io78f0714.h>
#define SENSORRED
#define ENABLE_UART
#define CLOSE_LOOP
#define CLEAR
#define SET
0
1
/* Regulator constants: */
#define norm_constant
#define actual_count_min
#define actual_count_max
2343750
213
15625
// constant to norm the timer count
// minimum valid count value (11003 rpm)
// maximum valid count value (150 rpm)
#endif
7.2 Global Variable Definitions
#ifndef __GLOBAL_H__
#define __GLOBAL_H__
#include
#include
#include
#include
<io78f0714.h>
<migration.h>
<intrinsics.h>
"definitions.h"
unsigned int MaxSpeed = 9540;
/* exchange variables for communication */
/* must be defined as unsigned integer */
unsigned int motor_rpm, reg_Y, DeltaX;
// measured values
unsigned int Kp, Ki;
// controller parameters
unsigned int PWM_CYCLE, DUTY_CYCLE, setpoint, deadtime; // control variables
// state
unsigned
unsigned
unsigned
unsigned
unsigned
variable
int onoff;
int disconnx;
int OverCurrent, SecureSel;
int Motor_Dir;
int Loop_Sel;
/* control variables */
unsigned int DCLevel = 249;
unsigned int phase_A;
unsigned int steps;
unsigned char newspeed;
unsigned char ovf;
// 0 = off, 1 = on, 2 = running
// 0: anti-clockwise, 1: clockwise
// 0: closed loop 1: open loop
// angle variable
// frequency variable
/* regulation variables */
Application Note U19166EE1V0AN00
25
Chapter 7
Source Code
unsigned int actual_count = 0;
// actual timer count value for speed
// (16 Bit = [0 ... 65535])
long Integrator;
/* motor position control variables */
unsigned char Motor_Pos;
unsigned int PHASE_A_LEFT[]
= {0, 0, 8130, 0, 49090,
0, 28610, 0, 18370,
unsigned int PHASE_A_RIGHT[] = {0, 0, 49090, 0, 8130,
0, 28610, 0, 38850,
0,
0,
0,
0,
59330,
38850};
59330,
18370};
#endif
7.3 Main Entry Program
/* pmsm_main.c */
#pragma language = extended
#include "global.h"
#include "definitions.h"
#include "init.h"
#include "regulation.h"
#include "mainfunctions.h"
#ifdef ENABLE_UART
#include "NecLib.h"
#endif
//----------------------------------------------------------------------------// Option Byte
//----------------------------------------------------------------------------#pragma constseg = OPTBYTE
__root const unsigned char option = 0x00;
#pragma constseg = default
#pragma constseg = SECUID
__root const unsigned char secuid[] =
{0x00, 0xFF, 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
#pragma constseg = default
//============================================================================
// MAIN
//============================================================================
#pragma language = extended
void main(void)
{
_DI();
// Disable all interrupts
/* uPD init */
init_Interrupt();
system_init();
var_init();
#ifdef ENABLE_UART
extern unsigned int* CommVarAddr[variable_no];
ClearAddresses ();
CommVarAddr[RPM]
CommVarAddr[REGY]
CommVarAddr[XD]
CommVarAddr[KP]
CommVarAddr[KI]
CommVarAddr[PWMCYCLE]
CommVarAddr[DUTYCYCLE]
CommVarAddr[SETPOINT]
26
=
=
=
=
=
=
=
=
&motor_rpm;
®_Y;
&DeltaX;
&Kp;
&Ki;
&PWM_CYCLE;
&DUTY_CYCLE;
&setpoint;
Application Note U19166EE1V0AN00
Source Code
Chapter 7
CommVarAddr[DEADTIME]
CommVarAddr[ONOFF]
CommVarAddr[DISCONNX]
CommVarAddr[OC]
CommVarAddr[MOTORDIR]
CommVarAddr[LOOP]
CommVarAddr[SSD]
CommVarAddr[MAXSPEED]
=
=
=
=
=
=
=
=
&deadtime;
&onoff;
&disconnx;
&OverCurrent;
&Motor_Dir;
&Loop_Sel;
&SecureSel;
&MaxSpeed;
SaveDefaultValue ();
CommStart();
start_51;
#endif
// transmission interval timer
#ifdef CLOSE_LOOP
start_50;
#endif
// regulation interval timer
_EI();
// Enable all interrupts
while (1)
{
if (onoff)
{
if (onoff == 1)
// system starts
{
Motor_Pos
= P0 & 0x0E;
phase_A
= PHASE_A_LEFT[Motor_Pos];
steps
= 62;
// reset frequency variable
system_start();
onoff
= 2;
}
#ifdef CLOSE_LOOP
if (onoff == 2)
{
if ((!Loop_Sel) && TMIF50) PIRegulation();
}
#endif
}
else
{
system_stop();
// setpoint changed, and =0, system stops
actual_count = 0;
motor_rpm
= 0;
Integrator
= 0;
newspeed
= 0;
}
if (newspeed > 1)
{
motor_rpm
= norm_constant / actual_count;
// normalize speed
steps
= motor_rpm / 10;
// synchronization
newspeed
= 1;
ovf
= 0;
}
else if (newspeed == 1 && OVF00 == 1)
{
ovf++;
OVF00 = 0;
if (ovf > 2)
// after 3 * 78.125KHz * 65536 = 2,5s
{
ovf = 0;
motor_rpm = 0;
if (setpoint)
{
disconnx = 1;
// device error, shutdown system
}
}
}
#ifdef ENABLE_UART
Application Note U19166EE1V0AN00
27
Chapter 7
Source Code
if (disconnx)
{
var_init();
}
if (TMIF51)
{
TMIF51 = 0;
CommUpdate ();
}
#endif
}
}
7.4 System Initialization
/* init.c */
#include "init.h"
#include "definitions.h"
extern unsigned int deadtime;
extern unsigned int PWM_CYCLE;
/*********************************************/
/****
H/W µPD INIT
****/
/*********************************************/
void system_init(void)
{
init_PORT();
init_OSC();
init_TW0();
init_TM00();
init_AD();
init_50();
init_51();
init_UART00();
}
/**************************/
/****
System start
****/
/**************************/
void system_start(void)
{
start_TW0;
start_TM00;
//start_AD;
INTTW0UD_on;
}
/*************************/
/****
System stop
****/
/*************************/
void system_stop(void)
{
INTTW0UD_off;
stop_TW0;
stop_TM00;
stop_AD;
}
/*************************/
/****
System stop
****/
/*************************/
void init_PORT(void)
{
// 7 6 5 4 3 2 1
EGP = 0x0E;
// 0 0 0 0 1 1 1
EGN = 0x0F;
// 0 0 0 0 1 1 1
//
| | |
28
Application Note U19166EE1V0AN00
0
0
1
|___TOFF7 Secure shut off
Source Code
Chapter 7
//
|_|_|_____Hall Ext. IRQ both edges
/*
Low voltage power module TRIP signal shuts off power to MOSFETs
It is active high and driven by P5.4
*/
PM5
= 0xEF;
/* P53 input for CR01 */
P54
= CLEAR;
/* Clear Trip Signal */
}
void init_OSC(void)
{
// IMS - Internal Memory Size
// 7 6 5 4 3 2 1 0
// | | | 0 |_|_|_|____ROM3 ROM2 ROM1 ROM0
// | | |
1
0
0
0
32KB Internal ROM
// |_|_|___RAM2 RAM1 RAM0
//
1
1
0
1024 bytes interal high-speed RAM
IMS = 0xC8;
/* Memory size switching */
PCC
= 0x00;
// MCM bit 7 6 5 4 3 2 1 0
//
0 0 0 0 0 0 0 |____MCM0
MCM0 = 1;
/* Sets division ratio */
0: Ring OSC
1: X1
/* X1 as input clock */
}
/****************************/
/**** Inverter timer
****/
/****************************/
void init_TW0(void)
{
TW0M
= 0;
TW0TRGS = 0;
TW0C
= 0x01;
TW0OC
= 0;
TW0CM3
= PWM_CYCLE;
TW0CM0
= 0;
TW0CM1
= 0;
TW0CM2
= 0;
TW0DTIME = deadtime;
TW0BFCM4 = PWM_CYCLE/2;
TW0BFCM3 = PWM_CYCLE;
TW0BFCM2 = 0;
TW0BFCM1 = 0;
TW0BFCM0 = 0;
}
/*****************************/
/**** 16-bit timer 00
****/
/*****************************/
void init_TM00(void)
{
CRC00 = 0x07;
PRM001 = SET;
PRM000 = CLEAR;
ES001 = SET;
ES000 = SET;
}
// underflow every second time
/* buffer - PWM carrier frequency */
/* buffer - PWM duty phase A */
/* buffer - PWM duty phase B */
/* buffer - PWM duty phase C */
/* Dead time */
/* ADC Trigger */
/* PWM carrier frequency */
/* initiial PWM duty phase C */
/* initiial PWM duty phase B */
/* initiial PWM duty phase A */
/* CR01 compare register */
/* Count clock 78.125 kHz */
/* TI000 pin Both Edges */
/**************************/
/**** 8-bit timer 50 ****/
/**************************/
void init_50(void)
{
// TCL50 bit 7 6 5 4 3 2 1 0
//
0 0 0 0 0 |_|_|____ TCL502 TCL501 TCL500
//
1
1
1
fx/8196 =
TCL50 = 0x07;
CR50 = 17;
/* 7ms */
}
2.44
KHz
/*****************************/
Application Note U19166EE1V0AN00
29
Chapter 7
Source Code
/****
8-bit timer 51
****/
/*****************************/
void init_51(void)
{
// TCL51 bit 7 6 5 4 3 2 1 0
//
0 0 0 0 0 |_|_|____ TCL512 TCL511 TCL501
//
1
1
0
fx/8196 =
TCL51 = 0x06;
CR51 = 12;
/* 5ms */
}
/*********************/
/****
UART00
****/
/*********************/
void init_UART00(void)
{
PM10
= SET;
PM13
= SET;
PM14
= CLEAR;
P14
= SET;
BRGC00 = 0x56;
// ASIM00
//
//
//
//
//
//
//
//ASIM
PS001
=
PS000
=
CL00
=
SL00
=
TXE00
=
RXE00
=
POWER00 =
STIF00
SRIF00
SRMK00
/* 115200 */
bit 7 6 5 4 3 2 1 0
| | | | | | | 1
| | | | | | |___SL00
0: 1 stop bit
| | | | | |_____CL00
1: 8 data bits
| | | |_|_______PS001 PS000
| | |___________RXE00
1: enable reception
| |_____________TXE00
1: enable transmission
|_______________POWER00
= 0xE5;
CLEAR;
CLEAR;
SET;
/* 8-bit */
CLEAR;
SET;
SET;
SET;
= CLEAR;
= CLEAR;
= CLEAR;
/*************************/
/****
Interrupts
****/
/*************************/
void init_Interrupt (void)
{
// interrupt definition
IF0L = 0x00;
IF0H = 0x00;
IF1L = 0x00;
IF1H = 0x00;
/*
/*
/*
/*
=
=
=
=
/* Enables receive interrupt */
0xE1;
0xFD;
0x87;
0xEF;
=
=
=
=
0xFF;
0xFD;
0xFF;
0xFF;
}
30
//
//
//
//
INT
INT
INT
INT
request
request
request
request
//
//
//
//
//
7
1
1
1
1
5
1
1
0
1
6
1
1
0
1
4
0
1
0
0
3
0
1
0
1
2
0
1
1
1
1
0
0
1
1
0
1
1
1
0
EXT 1,2,3 enabled, INTP0(TOFF) enabled */
TWO enabled */
TX, RX, RXE, TM01 enabled */
ADIF enabled */
PR0L
PR0H
PR1L
PR1H
KHz
// FLMD0
}
MK0L
MK0H
MK1L
MK1H
2.44
Application Note U19166EE1V0AN00
//
//
//
//
INT
INT
INT
INT
low
low
low
low
priority
priority
priority
priority
Source Code
Chapter 7
7.5 Main Functions
/* mainfunctions.c */
#include "mainfunctions.h"
#include "definitions.h"
// motor drive variables
extern unsigned int motor_rpm, reg_Y, DeltaX;
extern unsigned int Kp, Ki, Kd, PWM_CYCLE, DUTY_CYCLE, setpoint, deadtime;
extern
extern
extern
extern
unsigned
unsigned
unsigned
unsigned
int DCLevel;
int phase_A;
int steps;
char Motor_Pos;
// control variables
extern unsigned int onoff;
extern unsigned int disconnx;
extern unsigned int OverCurrent;
extern unsigned int Motor_Dir;
extern unsigned int Loop_Sel;
extern unsigned int SecureSel;
extern unsigned int SensorSel, BemfA_sel, BemfB_sel, BemfC_sel;
// sine angle variables
unsigned char phA, phase_B, phase_C;
// sinusoidal signal generating signal
const unsigned char SinTable[] = {0x00, 0x0D, 0x19, 0x25, 0x32, 0x3E, 0x4A,
0x56, 0x61, 0x6D, 0x78, 0x82, 0x8C, 0x96, 0xA0, 0xA9, 0xB2, 0xBA, 0xC1,
0xC8, 0xCF, 0xD5, 0xDA, 0xDF, 0xE3, 0xE7, 0xEA, 0xEC, 0xEE, 0xEF, 0xEF};
/***********************************************************/
/** Reload Inverter with new values -> ISR: TWOexception **/
/***********************************************************/
#pragma vector=INTTW0UD_vect
interrupt void INTTW0UD_exception (void)
{
phA = phase_A>>9;
if (Motor_Dir)
{
phase_C = phA
phase_B = phA
}
else
{
phase_C = phA
phase_B = phA
}
+ 40;
+ 80;
+ 80;
+ 40;
// BFCM3_value = PWM Cycle;
TW0BFCM3 = PWM_CYCLE;
if (phase_C >= 120) phase_C -=120;
if (phase_C < 30)
TW0BFCM2 = DCLevel + ((DUTY_CYCLE
else if (phase_C < 60)
TW0BFCM2 = DCLevel + ((DUTY_CYCLE
else if (phase_C < 90)
TW0BFCM2 = DCLevel - ((DUTY_CYCLE
else
TW0BFCM2 = DCLevel - ((DUTY_CYCLE
* SinTable[phase_C]) >> 8);
* SinTable[60-phase_C]) >> 8);
* SinTable[phase_C-60]) >> 8);
* SinTable[120-phase_C]) >> 8);
if (phase_B >= 120) phase_B -=120;
if (phase_B < 30)
TW0BFCM1 = DCLevel + ((DUTY_CYCLE * SinTable[phase_B]) >> 8);
else if (phase_B < 60)
TW0BFCM1 = DCLevel + ((DUTY_CYCLE * SinTable[60-phase_B]) >> 8);
Application Note U19166EE1V0AN00
31
Chapter 7
Source Code
else if (phase_B < 90)
TW0BFCM1 = DCLevel - ((DUTY_CYCLE * SinTable[phase_B-60]) >> 8);
else
TW0BFCM1 = DCLevel - ((DUTY_CYCLE * SinTable[120-phase_B]) >> 8);
if (phA < 30)
TW0BFCM0 = DCLevel
else if (phA < 60)
TW0BFCM0 = DCLevel
else if (phA < 90)
TW0BFCM0 = DCLevel
else
TW0BFCM0 = DCLevel
+ ((DUTY_CYCLE * SinTable[phA]) >> 8);
+ ((DUTY_CYCLE * SinTable[60-phA]) >> 8);
- ((DUTY_CYCLE * SinTable[phA-60]) >> 8);
- ((DUTY_CYCLE * SinTable[120-phA]) >> 8);
phase_A += steps;
if (phase_A >= 61440) phase_A -= 61440;
}
/***************************************************/
/** ISR: Over-current Signal
**/
/** Function: Trigger safety shutdown
**/
/***************************************************/
#pragma vector=INTP0_vect
interrupt void INTP0_exception (void)
{
if (SecureSel)
{
P54 = SET;
// set P54 -> TRIP high (@ 40-pin Ribbon connector)
OverCurrent = SET;
}
}
/***************************************************/
/** Communication Variable Initialization
**/
/***************************************************/
void var_init ()
{
motor_rpm
= 0;
// RPM,
reg_Y
= 0;
// REGY
DeltaX
= 0;
// XD,
Kp
= 50;
// KP,
Ki
= 1;
// KI,
PWM_CYCLE
= 500; // PWMCYCLE,
DUTY_CYCLE = 0;
// DUTYCYCLE,
setpoint
= 0;
// SETPOINT,
deadtime
= 0;
// DTIME
onoff
= 0;
disconnx
= 0;
OverCurrent = 0;
Motor_Dir
= 0;
Loop_Sel
= 0;
SecureSel
= 1;
}
7.6 Hall Sensor Signals Control
/* hall.c */
#include "hall.h"
#include "definitions.h"
extern
extern
extern
extern
extern
extern
extern
unsigned
unsigned
unsigned
unsigned
unsigned
unsigned
unsigned
char newspeed;
char Motor_Pos;
int Motor_Dir;
int phase_A;
int PHASE_A_LEFT[];
int PHASE_A_RIGHT[];
int actual_count;
unsigned int last_hall_time = 0;
32
Application Note U19166EE1V0AN00
// Count value (n-1) from TM00
Source Code
Chapter 7
unsigned int this_hall_time = 0;
// Count value (n) from TM00
//====================================================================
// Speed measurement of the motor
//====================================================================
#pragma vector=INTTM01_vect
interrupt void INTTM01_exception (void) //Speed_Meassurment()
{
this_hall_time = CR01;
if (this_hall_time <= last_hall_time)
actual_count = 0x10000 - last_hall_time + this_hall_time;
else
actual_count = this_hall_time - last_hall_time;
last_hall_time = this_hall_time;
if ((actual_count > actual_count_min) && (actual_count<actual_count_max))
newspeed++;
}
#ifdef SENSORRED
/*********************************************/
/****
Ext_ISR Detect Hall A
****/
/*********************************************/
#pragma vector=INTP1_vect
interrupt void INTP1_exception (void)
{
Motor_Pos = P0 & 0x0E;
if (Motor_Dir) phase_A = PHASE_A_RIGHT[Motor_Pos];
else
phase_A = PHASE_A_LEFT[Motor_Pos];
}
/*********************************************/
/****
Ext_ISR Detect Hall B
****/
/*********************************************/
#pragma vector=INTP2_vect
interrupt void INTP2_exception (void)
{
Motor_Pos = P0 & 0x0E;
if (Motor_Dir) phase_A = PHASE_A_RIGHT[Motor_Pos];
else
phase_A = PHASE_A_LEFT[Motor_Pos];
}
/*********************************************/
/****
Ext_ISR Detect Hall C
****/
/*********************************************/
#pragma vector=INTP3_vect
interrupt void INTP3_exception (void)
{
Motor_Pos = P0 & 0x0E;
if (Motor_Dir) phase_A = PHASE_A_RIGHT[Motor_Pos];
else
phase_A = PHASE_A_LEFT[Motor_Pos];
}
#endif
7.7 PI Controller
/* regulation.c */
#include <io78f0714.h>
#include "regulation.h"
#include "definitions.h"
extern
extern
extern
extern
extern
extern
unsigned
unsigned
unsigned
unsigned
unsigned
unsigned
int
int
int
int
int
int
setpoint;
motor_rpm;
Kp;
Ki;
reg_Y;
DeltaX;
Application Note U19166EE1V0AN00
33
Chapter 7
Source Code
extern unsigned int PWM_CYCLE;
extern unsigned int DUTY_CYCLE;
extern long Integrator;
#ifdef CLOSE_LOOP
/* local variables */
static long lbuf; // local long type calculation buffer
int ERR;
// speed error
long Yp;
// Y proportional part
long Yi;
// Y integral part
int Ytotal;
// Y result
/* value range limits */
#define Yp_max
#define Yp_min
#define Yi_max
#define Yi_min
#define Integrator_max
#define Integrator_min
#define Y_max
#define Y_min
9768960
-9768960
9768960
-9768960
9768960
-9768960
9540
0
//
//
//
//
//
+9540
-9540
+9540
-9540
+9540
*
*
*
*
*
1024
1024
1024
1024
1024
void PIRegulation(void)
{
TMIF50 = 0;
/*
PI Regulator
Range of values:
setpoint
motor_rpm
ERR
=
0%...+100% = (integer) =
=
0%...+100% = (integer) =
= -100%...+100% = (integer) =
0...+9540
600...+9540
-9540...0...+9540
Kp
Ki
*/
= -100%...+100% = (integer) =
= -100%...+100% = (integer) =
-1024...0...+1024
-1024...0...+1024
// calculate ERR
ERR = setpoint - motor_rpm;
DeltaX = ERR;
//
//
if (ERR < 0) DUTY_CYCLE--;
if (ERR > 0) DUTY_CYCLE++;
// calculate Yp and limit
// calculate Yp = ERR * Kp;
lbuf = ERR;
lbuf *= Kp;
// limit Yp
if
(lbuf > Yp_max) lbuf = Yp_max;
else if (lbuf < Yp_min) lbuf = Yp_min;
Yp = lbuf;
// calculate Yi and limit
// calculate Yi(t) = ERR * Ki * t;
lbuf = ERR;
lbuf *= Ki;
// limit Yi
if
(lbuf > Yi_max) lbuf = Yi_max;
else if (lbuf < Yi_min) lbuf = Yi_min;
Integrator = (Integrator + lbuf);
if
(Integrator > Integrator_max) Integrator = Integrator_max;
else if (Integrator < Integrator_min) Integrator = Integrator_min;
Yi = Integrator;
// calculate Y and limit */
34
Application Note U19166EE1V0AN00
Source Code
Chapter 7
lbuf = Yp + Yi;
Ytotal = lbuf >> 10;
// normalizing by divide by 1024 (2^10)
Ytotal = reg_Y + Ytotal;
// limit Y
if
(Ytotal > Y_max)
else if (Ytotal < Y_min)
reg_Y =
lbuf =
//lbuf
lbuf =
Ytotal = Y_max;
Ytotal = Y_min;
Ytotal;
reg_Y;
= (lbuf * PWM_CYCLE / Y_max) >> 1;
(lbuf * PWM_CYCLE / 8200) >> 1;
// limit DUTY_CYCLE
if
(lbuf > PWM_CYCLE/2) lbuf = PWM_CYCLE/2;
else if (lbuf < 0) lbuf = 0;
DUTY_CYCLE
= lbuf;
}
#endif
Application Note U19166EE1V0AN00
35