Two-phase stepping motor PWM control method based on three-phase inverter topological structure

Abstract

The invention discloses a two-phase stepping motor PWM control method based on a three-phase inverter topological structure, and the method comprises the steps: connecting a DC bus voltage through employing the three-phase inverter topological structure, and connecting an a-phase winding and a b-phase winding of a two-phase stepping motor into the three-phase inverter topological structure in series. The on-off of each power switch device in the three-phase inverter topological structure is controlled through a PWM (Pulse Width Modulation) signal to realize the control of the two-phase stepping motor; the two-phase stepping motor driving control circuit has the advantages that the driving control of the two-phase stepping motor is realized by only adopting six power switch devices, and the hardware cost is relatively low.

Description

Technical Field

[0001] The invention relates to a two-phase stepper motor control method, in particular to a two-phase stepper motor PWM control method based on a three-phase inverter topology structure. Background Art

[0002] Existing two-phase stepper motor control methods are usually implemented based on a typical driving topology structure implemented by a double H-bridge. The two H-bridges in the typical driving topology structure drive the a-phase winding and the b-phase winding of the two-phase stepper motor respectively.

[0003] Each H-bridge is composed of four power switch devices, and each winding of the two-phase stepper motor requires four power switch devices to drive. The a-phase winding and the b-phase winding of the two-phase stepper motor require a total of eight power switch devices to drive. Therefore, the hardware cost of the existing two-phase stepper motor control method is relatively high. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a two-phase stepping motor PWM control method based on a three-phase inverter topology structure with low hardware cost.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a two-phase stepper motor PWM control method based on a three-phase inverter topology structure, which connects the DC bus voltage by adopting the three-phase inverter topology structure, and connects the a-phase winding and the b-phase winding of the two-phase stepper motor in series to the three-phase inverter topology structure, and controls the on and off of each power switch device in the three-phase inverter topology structure through PWM signals to realize the control of the two-phase stepper motor.

[0006] The three-phase inverter topology structure includes six power switch devices, all of which are MOS tubes or 1GBT tubes. The six power switch devices are respectively referred to as the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device; the first power switch device and the second power switch device constitute a first bridge arm, which is called a U arm, the third power switch device and the fourth power switch device constitute a second bridge arm, which is called a V arm, and the fifth power switch device and the sixth power switch device constitute a third bridge arm, which is called a W arm; when the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device are all MOS tubes When, the source of the first power switch device is the first connection end of the U arm, the drain of the first power switch device is connected to the source of the second power switch device, and the connection end thereof is the common end of the U arm, the drain of the second power switch device is the second connection end of the U arm, the source of the third power switch device is the first connection end of the V arm, the drain of the third power switch device is connected to the source of the fourth power switch device, and the connection end thereof is the common end of the V arm, the drain of the fourth power switch device is the second connection end of the V arm, the source of the fifth power switch device is the first connection end of the W arm, the drain of the fifth power switch device is connected to the source of the sixth power switch device, and the connection end thereof is the common end of the W arm, and the drain of the sixth power switch device is the second connection end of the W arm;When the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device are all IGBT tubes, the collector of the first power switch device is the first connection end of the U arm, the emitter of the first power switch device is connected to the collector of the second power switch device, and the connection end thereof is the common end of the U arm, the emitter of the second power switch device is the second connection end of the U arm, the collector of the third power switch device is the first connection end of the V arm, the emitter of the third power switch device is connected to the collector of the fourth power switch device, and the connection end thereof is the common end of the V arm, the emitter of the fourth power switch device is the second connection end of the V arm, the collector of the fifth power switch device is the first connection end of the W arm, the emitter of the fifth power switch device is connected to the collector of the sixth power switch device, and the connection end thereof is the common end of the W arm, the emitter of the sixth power switch device is connected to the collector of the sixth power switch device, and the connection end thereof is the common end of the W arm, and the emitter of the sixth power switch device is connected to the collector of the sixth power switch device. The emitter is the second connection end of the W arm; when the two-phase stepper motor is controlled, the DC bus voltage is connected between the first connection end and the second connection end of the U arm, between the first connection end and the second connection end of the V arm, and between the first connection end and the second connection end of the W arm. According to the control requirements of the two-phase stepper motor, one end of the two windings of the two-phase stepper motor is connected together as the first connection end of the two-phase stepper motor, and the other ends of the two windings of the two-phase stepper motor are respectively used as the second connection end and the third connection end of the two-phase stepper motor. The first connection end, the second connection end and the third connection end of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm in a one-to-one correspondence. The gate of the first power switch device, the gate of the second power switch device, the gate of the third power switch device, the gate of the fourth power switch device, the gate of the fifth power switch device and the gate of the sixth power switch device are respectively connected to a PWM signal for controlling the on and off thereof. ;

[0007] The DC bus voltage is recorded as Vdc, and the voltage utilization duty cycle of the DC bus voltage is recorded as Ds, the value range of Ds is 0-1, and the voltage utilization of the DC bus voltage is equal to 1-Ds; the PWM signal connected to the gate of the first power switch device is called the first PWM signal, the PWM signal connected to the gate of the second power switch device is called the second PWM signal, the PWM signal connected to the gate of the third power switch device is called the third PWM signal, the PWM signal connected to the gate of the fourth power switch device is called the fourth PWM signal, the PWM signal connected to the gate of the fifth power switch device is called the fifth PWM signal, and the PWM signal connected to the gate of the sixth power switch device is called the sixth PWM signal; the duty cycle of the first PWM signal is recorded as Du, the value range of Du is 0-1, when Du=1, the first power switch device is fully turned on, when Du=0, the first power switch device is fully turned off; the second PWM signal and the first PWM signal are The present invention provides two complementary PWM signals; the duty cycle of the third PWM signal is recorded as Dv, the value range of Dv is 0-1, when Dv=1, the third power switch device is fully turned on, when Dv=0, the third power switch device is fully turned off; the fourth PWM signal and the third PWM signal are two complementary PWM signals; the duty cycle of the fifth PWM signal is recorded as Dw, the value range of Dw is 0-1, when Dw=1, the fifth power switch device is fully turned on, when Dw=0, the fifth power switch device is The sixth PWM signal and the fifth PWM signal are two complementary PWM signals; the two windings of the two-phase stepper motor are respectively the a-phase winding and the b-phase winding, the two ends of the a-phase winding of the two-phase stepper motor are respectively referred to as a+ and a-, the two ends of the b-phase winding are respectively referred to as b+ and b-, the a-phase winding and the b-phase winding have four forms: 1, a-, b-, (a+, b+); 2, a-, b+, (a+, b-); 3, a+, b-, (a-, b+); 4, a+, b+, (a-, b-);Among them, (a-, b-) means a- and b- are connected together, (a+, b+) means a+ and b+ are connected together, (a+, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a- and b- are connected together. When the two windings of the two-phase stepper motor are connected in a certain connection form and then connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure, there are 6 connection methods, that is, the two windings of the two-phase stepper motor and the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure have 24 connection methods, among which the first connection method is: a+ is connected to the common end of the U arm The first connection method is: a+ to the common end of the V arm, b+ to the common end of the W arm, (a-, b-) to the common end of the W arm; the second connection method is: a+ to the common end of the U arm, b+ to the common end of the W arm, (a-, b-) to the common end of the V arm; the third connection method is: a+ to the common end of the V arm, b+ to the common end of the U arm, (a-, b-) to the common end of the W arm; the fourth connection method is: a+ to the common end of the V arm, b+ to the common end of the W arm, (a-, b-) to the common end of the U arm; the fifth connection method is: a+ to the common end of the W arm, b+ to the common end of the U arm, (a-, b-) to the common end of the V arm; the sixth connection method is: a+ to the common end of the W arm, b+ to the common end of the V arm, (a-, b-) to the common end of the U arm ; The 7th connection method is: a+ is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a-, b+) are connected to the common end of the W arm; the 8th connection method is: a+ is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a-, b+) are connected to the common end of the V arm; the 9th connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a-, b+) are connected to the common end of the W arm; the 10th connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a-, b+) are connected to the common end of the U arm; the 11th connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a-, b+) are connected to the common end of the V arm; the 12th connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the The common end of the V arm, (a-, b+) is connected to the common end of the U arm; the 13th connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a+, b+) is connected to the common end of the W arm; the 14th connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a+, b+) is connected to the common end of the V arm; the 15th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a+, b+) is connected to the common end of the W arm; the 16th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a+, b+) is connected to the common end of the U arm; the 17th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a+, b+) is connected to the common end of the V arm;The 18th connection method is: a- connected to the common end of the W arm, b- connected to the common end of the V arm, (a+, b+) connected to the common end of the U arm; the 19th connection method is: a- connected to the common end of the U arm, b+ connected to the common end of the V arm, (a+, b-) connected to the common end of the W arm; the 20th connection method is: a- connected to the common end of the U arm, b+ connected to the common end of the W arm, (a+, b-) connected to the common end of the V arm; the 21st connection method is: a- connected to the common end of the V arm, b+ connected to the common end of the U arm, (a+, b-) connected to the common end of the W arm; the 22nd connection method is: a- connected to the common end of the V arm, b+ connected to the common end of the W arm, (a+, b-) connected to the common end of the U arm; the 23rd connection method is: a - is connected to the common end of the W arm, b+ is connected to the common end of the U arm, and (a+, b-) is connected to the common end of the V arm; the 24th connection mode is: a- is connected to the common end of the W arm, b+ is connected to the common end of the V arm, and (a+, b-) is connected to the common end of the U arm; the working voltage of the a-phase winding is recorded as Ualpha, and the working voltage of the b-phase winding is recorded as Ubeta, Ualpha and Ubeta are respectively less than or equal to Vdc, and according to the current values ​​of Ualpha and Ubeta, the current values ​​of the duty ratios of the first PWM signal, the second PWM signal, the third PWM signal, the fourth PWM signal, the fifth PWM signal, and the sixth PWM signal are adaptively set to control the two-phase stepper motor. ;

[0008] The two windings of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure in 24 connection modes. When the two-phase stepper motor is controlled, the duty ratios of the PWM signals connected to the six power switch devices are:

[0009] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the first connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds, where || is the absolute value sign; 2. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0, Du =Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds;

[0010] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the second connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv= |Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds;

[0011] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the third connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Dw+|Ubeta| / Vdc+Ds eta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds;

[0012] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the fourth connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds. a| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds;

[0013] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the fifth connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Dv+|Ubeta| / Vdc+Ds eta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc;

[0014] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the sixth connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds a| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc;

[0015] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the seventh connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds;

[0016] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the eighth connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc;

[0017] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 9th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds;

[0018] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 10th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc;

[0019] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 11th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds;

[0020] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 12th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds;

[0021] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 13th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; beta>0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds;

[0022] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 14th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc When beta>0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vd+Ds;

[0023] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 15th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha>0 and When Ubeta>0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc, Dw=Ds;

[0024] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 16th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc When beta>0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds;

[0025] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 17th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; When beta>0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds;

[0026] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 18th connection method: 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; When beta>0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds;

[0027] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 19th connection method, 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc dc+Ds; 3. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds;

[0028] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 20th connection method: 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds;

[0029] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 21st connection method: 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc dc+Ds; 3. When Ualpha>0 and Ubeta>0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds;

[0030] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 22nd connection method, first, when Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; second, when Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds; 3. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds;

[0031] If the two windings of the two-phase stepper motor and the three-phase inverter topology are connected in the 23rd way:

[0032] 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 3. When Ualpha>0 and When Ubeta>0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc;

[0033] If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 24th connection method: 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha | / Vdc; 3. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc.

[0034] Compared with the prior art, the advantage of the present invention lies in that a three-phase inverter topology is adopted to access the DC bus voltage, and the a-phase winding and the b-phase winding of the two-phase stepper motor are connected in series to the three-phase inverter topology, and the on and off of each power switch device in the three-phase inverter topology is controlled by a PWM signal to realize the control of the two-phase stepper motor. Since the three-phase inverter topology is realized by six power switch devices, the present invention only uses six power switch devices to realize the drive control of the two-phase stepper motor, and the hardware cost is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a connection structure diagram of a three-phase inverter topology structure and a two-phase stepper motor when the two-phase stepper motor PWM control method based on a three-phase inverter topology structure of the present invention controls the two-phase stepper motor. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below with reference to the accompanying drawings.

[0037] Embodiment 1: A two-phase stepper motor PWM control method based on a three-phase inverter topology structure, which connects the DC bus voltage by adopting a three-phase inverter topology structure, and connects the a-phase winding and the b-phase winding of the two-phase stepper motor in series to the three-phase inverter topology structure, and controls the on and off of each power switch device in the three-phase inverter topology structure by PWM signals to realize the control of the two-phase stepper motor.

[0038] In this embodiment, since the three-phase inverter topology is implemented by six power switching devices, the present invention only uses six power switching devices to realize the drive control of the two-phase stepper motor. Compared with the existing two-phase stepper motor PWM control method based on the typical drive topology structure realized by the double H-bridge, two power switching devices are saved and the hardware cost is significantly reduced.

[0039] Embodiment 2: This embodiment is basically the same as Embodiment 1, except that: Figure 1As shown, in this embodiment, the three-phase inverter topology structure includes six power switch devices, all of which are MOS tubes or 1GBT tubes, and the six power switch devices are respectively called the first power switch device T1, the second power switch device T2, the third power switch device T3, the fourth power switch device T4, the fifth power switch device T5 and the sixth power switch device T6; the first power switch device T1 and the second power switch device T2 constitute a first bridge arm, which is called a U arm, the third power switch device T3 and the fourth power switch device T4 constitute a second bridge arm, which is called a V arm, and the fifth power switch device T5 and the sixth power switch device T6 constitute a third bridge arm. It is called the W arm; when the first power switch device T1, the second power switch device T2, the third power switch device T3, the fourth power switch device T4, the fifth power switch device T5 and the sixth power switch device T6 are all MOS tubes, the source of the first power switch device T1 is the first connection end of the U arm, the drain of the first power switch device T1 is connected to the source of the second power switch device T2, and the connection end thereof is the common end of the U arm, the drain of the second power switch device T2 is the second connection end of the U arm, the source of the third power switch device T3 is the first connection end of the V arm, the drain of the third power switch device T3 is connected to the source of the fourth power switch device T4, and the connection end thereof is the common end of the V arm. The drain of the fourth power switch device T4 is the second connection end of the V arm, the source of the fifth power switch device T5 is the first connection end of the W arm, the drain of the fifth power switch device T5 is connected to the source of the sixth power switch device T6, and the connection end thereof is the common end of the W arm, and the drain of the sixth power switch device T6 is the second connection end of the W arm; when the first power switch device T1, the second power switch device T2, the third power switch device T3, the fourth power switch device T4, the fifth power switch device T5 and the sixth power switch device T6 are all 1GBT tubes, the collector of the first power switch device T1 is the first connection end of the U arm, and the emitter of the first power switch device T1 and the second power switch The collector of the device T2 is connected, and its connection end is the common end of the U arm, the emitter of the second power switch device T2 is the second connection end of the U arm, the collector of the third power switch device T3 is the first connection end of the V arm, the emitter of the third power switch device T3 is connected to the collector of the fourth power switch device T4, and its connection end is the common end of the V arm, the emitter of the fourth power switch device T4 is the second connection end of the V arm, the collector of the fifth power switch device T5 is the first connection end of the W arm, the emitter of the fifth power switch device T5 is connected to the collector of the sixth power switch device T6, and its connection end is the common end of the W arm, and the emitter of the sixth power switch device T6 is the second connection end of the W arm;When the two-phase stepper motor is controlled, the DC bus voltage is connected between the first connection end and the second connection end of the U arm, between the first connection end and the second connection end of the V arm, and between the first connection end and the second connection end of the W arm. According to the control requirements of the two-phase stepper motor, one end of the two windings of the two-phase stepper motor is connected together as the first connection end of the two-phase stepper motor, and the other ends of the two windings of the two-phase stepper motor are respectively used as the second connection end and the third connection end of the two-phase stepper motor. The first connection end, the second connection end, and the third connection end of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm, and the common end of the W arm in a one-to-one correspondence. The gate of the first power switch device T1, the gate of the second power switch device T2, the gate of the third power switch device T3, the gate of the fourth power switch device T4, the gate of the fifth power switch device T5, and the gate of the sixth power switch device T6 are respectively connected to a PWM signal for controlling the on and off thereof. ;

[0040] The two windings of a two-phase stepper motor are a-phase winding and b-phase winding respectively. The two ends of the a-phase winding of the two-phase stepper motor are called a+ and a- respectively, and the two ends of the b-phase winding are called b+ and b- respectively. There are four ways to connect the a-phase winding and the b-phase winding: 1. a-, b-, (a+, b+); 2. a-, b+, (a+, b-); 3. a+, b-, (a-, b+); 4. a+, b+, (a-, b-); among them, (a-, b-) means a- and b- are connected together, (a+, b+) means a+ and b+ are connected together, (a+, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a- and b- are connected together. Therefore, when the two windings of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology, there are 12 connection modes. In this embodiment, the two windings of the two-phase stepper motor adopt the first connection mode, and a- and b- are connected to the common end of the V arm, a+ is connected to the common end of the U arm, and b+ is connected to the common end of the W arm.

[0041] Embodiment 3: This embodiment is basically the same as Embodiment 2, except that: in this embodiment, the DC bus voltage is recorded as Vdc, the voltage utilization duty cycle of the DC bus voltage is recorded as Ds, the value range of Ds is 0 to 1, and the voltage utilization of the DC bus voltage is equal to 1-Ds; the PWM signal connected to the gate of the first power switch device T1 is called the first PWM signal g1, the PWM signal connected to the gate of the second power switch device T2 is called the second PWM signal g2, the PWM signal connected to the gate of the third power switch device T3 is called the third PWM signal g3, the PWM signal connected to the gate of the fourth power switch device T4 is called the fourth PWM signal g4, ​​the PWM signal connected to the gate of the fifth power switch device T5 is called the fifth PWM signal g5, and the PWM signal connected to the gate of the sixth power switch device T6 is called the sixth PWM signal g6; the first PWM signal g The duty cycle of 1 is recorded as Du, and the value range of Du is 0-1. When Du=1, the first power switch device T1 is fully turned on, and when Du=0, the first power switch device T1 is fully turned off; the second PWM signal g2 and the first PWM signal g1 are two complementary PWM signals; the duty cycle of the third PWM signal g3 is recorded as Dv, and the value range of Dv is 0-1. When Dv=1, the third power switch device T3 is fully turned on, and when Dv=0, the third power switch device T3 is fully turned off; the fourth PWM signal g4 and the third PWM signal g3 are two complementary PWM signals; the duty cycle of the fifth PWM signal g5 is recorded as Dw, and the value range of Dw is 0-1. When Dw=1, the fifth power switch device T5 is fully turned on, and when Dw=0, the fifth power switch device T5 is fully turned off; the sixth PWM signal g6 and the fifth PWM signal g5 are two complementary PWM signals;

[0042] The two windings of a two-phase stepper motor are a-phase winding and b-phase winding respectively. The two ends of the a-phase winding of the two-phase stepper motor are called a+ and a- respectively, and the two ends of the b-phase winding are called b+ and b- respectively. There are four forms of a-phase winding and b-phase winding: 1. a-, b-, (a+, b+); 2. a-, b+, (a+, b-); 3. a+, b-, (a-, b+); 4. a+, b+, (a-, b-); among them, (a-, b-) means a- and b- are connected together, (a+, b+) means a+ and b+ are connected together, (a+, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a- and b- are connected together. When the two phases After the two windings of the stepper motor are connected in a certain connection form, when they are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure, there are 6 connection methods, that is, the two windings of the two-phase stepper motor and the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure have 24 connection methods, among which the first connection method is: a+ connected to the common end of the U arm, b+ connected to the common end of the V arm, (a-, b-) connected to the common end of the W arm; the second connection method is: a+ connected to the common end of the U arm, b+ connected to the common end of the W arm, (a-, b-) connected to the common end of the V arm; the third connection method is: a+ connected to the common end of the V arm, b+ connected to the common end of the U arm, (a-, b-) connected The common end of the W arm; the fourth connection method is: a+ connected to the common end of the V arm, b+ connected to the common end of the W arm, (a-, b-) connected to the common end of the U arm; the fifth connection method is: a+ connected to the common end of the W arm, b+ connected to the common end of the U arm, (a-, b-) connected to the common end of the V arm; the sixth connection method is: a+ connected to the common end of the W arm, b+ connected to the common end of the V arm, (a-, b-) connected to the common end of the U arm; the seventh connection method is: a+ connected to the common end of the U arm, b- connected to the common end of the V arm, (a-, b+) connected to the common end of the W arm; the eighth connection method is: a+ connected to the common end of the U arm, b- connected to the common end of the W arm, (a-, b+) connected to the common end of the V arm; the ninth connection method is: a+ connected to the common end of the V arm, b- The common end of the U arm is connected to (a-, b+) the common end of the W arm; the tenth connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a-, b+) is connected to the common end of the U arm; the eleventh connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a-, b+) is connected to the common end of the V arm; the twelfth connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a-, b+) is connected to the common end of the U arm; the thirteenth connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a+, b+) is connected to the common end of the W arm; the fourteenth connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a+, b+) is connected to the common end of the V arm;The 15th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the W arm; the 16th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a+, b+) are connected to the common end of the U arm; the 17th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the V arm; the 18th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a+, b+) are connected to the common end of the U arm; the 19th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the W arm; The 20th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the V arm; the 21st connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the W arm; the 22nd connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the U arm; the 23rd connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the V arm; the 24th connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the U arm;

[0043] The working voltage of the a-phase winding is denoted as Ualpha, and the working voltage of the b-phase winding is denoted as Ubeta. Ualpha and Ubeta are respectively less than or equal to Vdc. According to the current values ​​of Ualpha and Ubeta, the current values ​​of the duty cycles of the first PWM signal g1, the second PWM signal g2, the third PWM signal g3, the fourth PWM signal g4, ​​the fifth PWM signal g5 and the sixth PWM signal g6 are adaptively set to control the two-phase stepper motor.

[0044] In this embodiment, the DC bus voltage is recorded as Vdc, the voltage utilization duty cycle of the DC bus voltage is recorded as Ds, the value range of Ds is 0-1, and the voltage utilization of the DC bus voltage is equal to 1-Ds; the PWM signal connected to the gate of the first power switch device T1 is called the first PWM signal g1, the PWM signal connected to the gate of the second power switch device T2 is called the second PWM signal g2, the PWM signal connected to the gate of the third power switch device T3 is called the third PWM signal g3, the PWM signal connected to the gate of the fourth power switch device T4 is called the fourth PWM signal g4, ​​the PWM signal connected to the gate of the fifth power switch device T5 is called the fifth PWM signal g5, and the PWM signal connected to the gate of the sixth power switch device T6 is called the sixth PWM signal g6; the duty cycle of the first PWM signal g1 is recorded as Du, Du The value range of Du is 0-1. When Du=1, the first power switch device T1 is fully turned on. When Du=0, the first power switch device T1 is fully turned off. The second PWM signal g2 and the first PWM signal g1 are two complementary PWM signals. The duty cycle of the third PWM signal g3 is recorded as Dv. The value range of Dv is 0-1. When Dv=1, the third power switch device T3 is fully turned on. When Dv=0, the third power switch device T3 is fully turned off. The fourth PWM signal g4 and the third PWM signal g3 are two complementary PWM signals. The duty cycle of the fifth PWM signal g5 is recorded as Dw. The value range of Dw is 0-1. When Dw=1, the fifth power switch device T5 is fully turned on. When Dw=0, the fifth power switch device T5 is fully turned off. The sixth PWM signal g6 and the fifth PWM signal g5 are two complementary PWM signals.

[0045] The two windings of a two-phase stepper motor are a-phase winding and b-phase winding respectively. The two ends of the a-phase winding of the two-phase stepper motor are called a+ and a- respectively, and the two ends of the b-phase winding are called b+ and b- respectively. There are four forms of a-phase winding and b-phase winding: 1. a-, b-, (a+, b+); 2. a-, b+, (a+, b-); 3. a+, b-, (a-, b+); 4. a+, b+, (a-, b-); among them, (a-, b-) means a- and b- are connected together, (a+, b+) means a+ and b+ are connected together, (a+, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a- and b- are connected together. When the two phases After the two windings of the stepper motor are connected in a certain connection form, when they are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure, there are 6 connection methods, that is, the two windings of the two-phase stepper motor and the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure have 24 connection methods, among which the first connection method is: a+ connected to the common end of the U arm, b+ connected to the common end of the V arm, (a-, b-) connected to the common end of the W arm; the second connection method is: a+ connected to the common end of the U arm, b+ connected to the common end of the W arm, (a-, b-) connected to the common end of the V arm; the third connection method is: a+ connected to the common end of the V arm, b+ connected to the common end of the U arm, (a-, b-) connected The common end of the W arm; the fourth connection method is: a+ connected to the common end of the V arm, b+ connected to the common end of the W arm, (a-, b-) connected to the common end of the U arm; the fifth connection method is: a+ connected to the common end of the W arm, b+ connected to the common end of the U arm, (a-, b-) connected to the common end of the V arm; the sixth connection method is: a+ connected to the common end of the W arm, b+ connected to the common end of the V arm, (a-, b-) connected to the common end of the U arm; the seventh connection method is: a+ connected to the common end of the U arm, b- connected to the common end of the V arm, (a-, b+) connected to the common end of the W arm; the eighth connection method is: a+ connected to the common end of the U arm, b- connected to the common end of the W arm, (a-, b+) connected to the common end of the V arm; the ninth connection method is: a+ connected to the common end of the V arm, b- The common end of the U arm is connected to (a-, b+) the common end of the W arm; the tenth connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a-, b+) is connected to the common end of the U arm; the eleventh connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a-, b+) is connected to the common end of the V arm; the twelfth connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a-, b+) is connected to the common end of the U arm; the thirteenth connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a+, b+) is connected to the common end of the W arm; the fourteenth connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a+, b+) is connected to the common end of the V arm;The 15th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the W arm; the 16th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a+, b+) are connected to the common end of the U arm; the 17th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the V arm; the 18th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a+, b+) are connected to the common end of the U arm; the 19th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the W arm; The 20th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the V arm; the 21st connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the W arm; the 22nd connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the U arm; the 23rd connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the V arm; the 24th connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the U arm;

[0046] The working voltage of the a-phase winding is denoted as Ualpha, and the working voltage of the b-phase winding is denoted as Ubeta. Ualpha and Ubeta are respectively less than or equal to Vdc. According to the current values ​​of Ualpha and Ubeta, the current values ​​of the duty cycles of the first PWM signal g1, the second PWM signal g2, the third PWM signal g3, the fourth PWM signal g4, ​​the fifth PWM signal g5 and the sixth PWM signal g6 are adaptively set to control the two-phase stepper motor.

[0047] When the two windings of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure in 24 connection modes, the duty ratio of the PWM signal connected to the six power switch devices is shown in Tables 1 to 12 in various cases when the two-phase stepper motor is controlled:

[0048] Table 1: Connection method 1 and connection method 2

[0049]

[0050]

[0051] Table 2: Connection method 3 and connection method 4

[0052]

[0053] Table 3: Connection method 5 and connection method 6

[0054]

[0055]

[0056] Table 4: The 7th and 8th connection methods

[0057]

[0058] Table 5: Connection method 9 to connection method 10

[0059]

[0060]

[0061] Table 6: 11th and 12th connection methods

[0062]

[0063] Table 7: Connection method 13 and connection method 14

[0064]

[0065]

[0066] Table 8: Connection method 15 and connection method 16

[0067]

[0068] Table 9: Connection method 17 and connection method 18

[0069]

[0070]

[0071] Table 10: Connection method 19 and connection method 10

[0072]

[0073] Table 11: Connection method 21 and connection method 22

[0074]

[0075]

[0076] Table 12: Connection method 23 and connection method 24

[0077]

[0078] To summarize, the two-phase stepper motor PWM control method based on the three-phase inverter topology structure of the present invention adopts the three-phase inverter topology structure. When the two windings of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure in any connection method, the duty cycle of the first PWM signal g1, the second PWM signal g2, the third PWM signal g3, the fourth PWM signal g4, ​​the fifth PWM signal g5 and the sixth PWM signal g6 can be adaptively set in real time according to the working voltage of the a-phase winding and the working voltage of the b-phase winding, thereby realizing the control of the two-phase stepper motor with a lower hardware cost.

Claims

1. A two-phase stepper motor PWM control method based on a three-phase inverter topology structure, characterized in that A three-phase inverter topology structure is adopted to access the DC bus voltage, and the a-phase winding and the b-phase winding of the two-phase stepper motor are connected in series to the three-phase inverter topology structure. The on and off of each power switch device in the three-phase inverter topology structure is controlled by PWM signals to realize the control of the two-phase stepper motor.

2. The two-phase stepper motor PWM control method based on the three-phase inverter topology structure according to claim 1 is characterized in that The three-phase inverter topology structure includes six power switch devices, all of which are MOS tubes or 1GBT tubes, and the six power switch devices are respectively referred to as a first power switch device, a second power switch device, a third power switch device, a fourth power switch device, a fifth power switch device and a sixth power switch device; the first power switch device and the second power switch device constitute a first bridge arm, which is referred to as a U arm, the third power switch device and the fourth power switch device constitute a second bridge arm, which is referred to as a V arm, and the fifth power switch device and the sixth power switch device constitute a third bridge arm, which is referred to as a W arm; When the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device are all MOS tubes, the source of the first power switch device is the first connection end of the U arm, the drain of the first power switch device is connected to the source of the second power switch device, and the connection end thereof is the common end of the U arm, the drain of the second power switch device is the second connection end of the U arm, the source of the third power switch device is the first connection end of the V arm, the drain of the third power switch device is connected to the source of the fourth power switch device, and the connection end thereof is the common end of the V arm, the drain of the fourth power switch device is the second connection end of the V arm, the source of the fifth power switch device is the first connection end of the W arm, the drain of the fifth power switch device is connected to the source of the sixth power switch device, and the connection end thereof is the common end of the W arm, and the drain of the sixth power switch device is the second connection end of the W arm; When the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device are all IGBT tubes, the collector of the first power switch device is the first connection end of the U arm, the emitter of the first power switch device is connected to the collector of the second power switch device, and the connection end thereof is the common end of the U arm, the emitter of the second power switch device is the second connection end of the U arm, the collector of the third power switch device is the first connection end of the V arm, the emitter of the third power switch device is connected to the collector of the fourth power switch device, and the connection end thereof is the common end of the V arm, the emitter of the fourth power switch device is the second connection end of the V arm, the collector of the fifth power switch device is the first connection end of the W arm, the emitter of the fifth power switch device is connected to the collector of the sixth power switch device, and the connection end thereof is the common end of the W arm, and the emitter of the sixth power switch device is the second connection end of the W arm; When the two-phase stepper motor is controlled, the DC bus voltage is connected between the first connection end and the second connection end of the U arm, between the first connection end and the second connection end of the V arm, and between the first connection end and the second connection end of the W arm. According to the control requirements of the two-phase stepper motor, one end of the two windings of the two-phase stepper motor is connected together as the first connection end of the two-phase stepper motor, and the other ends of the two windings of the two-phase stepper motor are respectively used as the second connection end and the third connection end of the two-phase stepper motor. The first connection end, the second connection end and the third connection end of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm in a one-to-one correspondence. The gate of the first power switch device, the gate of the second power switch device, the gate of the third power switch device, the gate of the fourth power switch device, the gate of the fifth power switch device and the gate of the sixth power switch device are respectively connected to a PWM signal for controlling the on and off thereof.

3. The two-phase stepper motor PWM control method based on the three-phase inverter topology structure according to claim 2 is characterized in that The DC bus voltage is recorded as Vdc, and the voltage utilization duty cycle of the DC bus voltage is recorded as Ds, the value range of Ds is 0-1, and the voltage utilization of the DC bus voltage is equal to 1-Ds; the PWM signal connected to the gate of the first power switch device is called the first PWM signal, the PWM signal connected to the gate of the second power switch device is called the second PWM signal, the PWM signal connected to the gate of the third power switch device is called the third PWM signal, the PWM signal connected to the gate of the fourth power switch device is called the fourth PWM signal, the PWM signal connected to the gate of the fifth power switch device is called the fifth PWM signal, and the PWM signal connected to the gate of the sixth power switch device is called the sixth PWM signal; the duty cycle of the first PWM signal is recorded as Du, The value range of Du is 0-1. When Du=1, the first power switch device is fully turned on, and when Du=0, the first power switch device is fully turned off. The second PWM signal and the first PWM signal are two complementary PWM signals. The duty cycle of the third PWM signal is recorded as Dv, and the value range of Dv is 0-1. When Dv=1, the third power switch device is fully turned on, and when Dv=0, the third power switch device is fully turned off. The fourth PWM signal and the third PWM signal are two complementary PWM signals. The duty cycle of the fifth PWM signal is recorded as Dw, and the value range of Dw is 0-1. When Dw=1, the fifth power switch device is fully turned on, and when Dw=0, the fifth power switch device is fully turned off. The sixth PWM signal and the fifth PWM signal are two complementary PWM signals. The two windings of the two-phase stepper motor are respectively an a-phase winding and a b-phase winding. The two ends of the a-phase winding of the two-phase stepper motor are respectively called a+ and a-, and the two ends of the b-phase winding are respectively called b+ and b-. The a-phase winding and the b-phase winding have four forms:

1. a-, b-, (a+, b+); 2. a-, b+, (a+, b-); 3. a+, b-, (a-, b+); 4. a+, b+, (a-, b-); wherein, (a-, b-) means a- and b- are connected together, (a+, b+) means a+ and b+ are connected together, (a+, b-) means a+ and b- are connected together, (a-, b+) means a- and b+ are connected together, (a-, b-) means a- and b- are connected together. When the two windings of the two-phase stepper motor are connected in a certain connection form and then connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure, there are 6 connection modes, that is, the two windings of the two-phase stepper motor and the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure have 24 connection modes. The first connection method is: a+ is connected to the common end of the U arm, b+ is connected to the common end of the V arm, and (a-, b-) are connected to the common end of the W arm; the second connection method is: a+ is connected to the common end of the U arm, b+ is connected to the common end of the W arm, and (a-, b-) are connected to the common end of the V arm; the third connection method is: a+ is connected to the common end of the V arm, b+ is connected to the common end of the U arm, and (a-, b-) are connected to the common end of the W arm; the fourth connection method is: a+ is connected to the common end of the V arm, b+ is connected to the common end of the W arm, and (a-, b-) are connected to the common end of the U arm; the fifth connection method is: a+ is connected to the common end of the W arm, b+ is connected to the common end of the U arm, and (a-, b-) are connected to the common end of the V arm; the sixth connection method is: a+ is connected to The common end of the W arm, b+ is connected to the common end of the V arm, and (a-, b-) is connected to the common end of the U arm; the seventh connection method is: a+ is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a-, b+) is connected to the common end of the W arm; the eighth connection method is: a+ is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a-, b+) is connected to the common end of the V arm; the ninth connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a-, b+) is connected to the common end of the W arm; the tenth connection method is: a+ is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a-, b+) is connected to the common end of the U arm; the eleventh connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the U arm, (a-, b+) are connected to the common end of the V arm; the 12th connection method is: a+ is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a-, b+) are connected to the common end of the U arm; the 13th connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the V arm, and (a+, b+) are connected to the common end of the W arm; the 14th connection method is: a- is connected to the common end of the U arm, b- is connected to the common end of the W arm, and (a+, b+) are connected to the common end of the V arm; the 15th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the W arm; the 16th connection method is: a- is connected to the common end of the V arm, b- is connected to the common end of the W arm, and (a+, b+) are connected to the common end of the U arm;The 17th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the U arm, and (a+, b+) are connected to the common end of the V arm; the 18th connection method is: a- is connected to the common end of the W arm, b- is connected to the common end of the V arm, and (a+, b+) are connected to the common end of the U arm; the 19th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the W arm; the 20th connection method is: a- is connected to the common end of the U arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the V arm; The 21st connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the W arm; the 22nd connection method is: a- is connected to the common end of the V arm, b+ is connected to the common end of the W arm, and (a+, b-) are connected to the common end of the U arm; the 23rd connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the U arm, and (a+, b-) are connected to the common end of the V arm; the 24th connection method is: a- is connected to the common end of the W arm, b+ is connected to the common end of the V arm, and (a+, b-) are connected to the common end of the U arm; The working voltage of the a-phase winding is denoted as Ualpha, and the working voltage of the b-phase winding is denoted as Ubeta. Ualpha and Ubeta are respectively less than or equal to Vdc. According to the current values ​​of Ualpha and Ubeta, the current values ​​of the duty cycles of the first PWM signal, the second PWM signal, the third PWM signal, the fourth PWM signal, the fifth PWM signal and the sixth PWM signal are adaptively set to control the two-phase stepper motor.

4. The two-phase stepper motor PWM control method based on the three-phase inverter topology structure according to claim 3 is characterized in that The two windings of the two-phase stepper motor are connected to the common end of the U arm, the common end of the V arm and the common end of the W arm of the three-phase inverter topology structure in 24 connection modes. When the two-phase stepper motor is controlled, the duty ratios of the PWM signals connected to the six power switch devices are: If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the first connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds, where || is the absolute value sign; 2. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0, Du =Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the second connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv= |Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the third connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Dw+|Ubeta| / Vdc+Ds eta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the fourth connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds. a| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the fifth connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=Dv+|Ubeta| / Vdc+Ds eta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the sixth connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds a| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 4. When Ualpha<0 and Ubeta<0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 5. When Ualpha<0 and Ubeta<0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the seventh connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the eighth connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 9th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|>| 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 10th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 11th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 12th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 3. When Ualpha<=0 and Ubeta>=0 and |Ualpha|> 4. When Ualpha<=0 and Ubeta>=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 13th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; beta>0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 14th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc When beta>0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vd+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 15th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 3. When Ualpha>0 and When Ubeta>0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 16th connection method, 1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc When beta>0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 17th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; When beta>0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ualpha| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 18th connection method:

1. When Ualpha>=0 and Ubeta<=0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 2. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 3. When Ualpha>0 and Ubeta>0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; When beta>0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 19th connection method, 1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=Dw-|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Dw-|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc dc+Ds; 3. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=Dw+|Ubeta| / Vdc, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dw+|Ualpha| / Vdc, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 20th connection method:

1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Dv-|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; 3. When Ualpha>0 and Ubeta>0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Dv+|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Dv+|Ualpha| / Vdc, Dv=|Ubeta| / Vdc+Ds, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 21st connection method:

1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Dw-|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=Dw-|Ualpha| / Vdc, Dw=|Ubeta| / Vdc dc+Ds; 3. When Ualpha>0 and Ubeta>0, Du=Dw+|Ubeta| / Vdc, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=Dw+|Ualpha| / Vdc, Dw=|Ubeta| / Vdc+Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 22nd connection method, first, when Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du-|Ubeta| / Vdc; second, when Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Du-|Ualpha| / Vdc, Dw=Ds; 3. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Ds, Dw=Du+|Ubeta| / Vdc; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ualpha| / Vdc+Ds, Dw=|Ubeta| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Du+|Ualpha| / Vdc, Dw=Ds; If the two windings of the two-phase stepper motor and the three-phase inverter topology are connected in the 23rd way:

1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=Dv-|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv-|Ubeta| / Vdc; 3. When Ualpha>0 and When Ubeta>0, Du=Dv+|Ubeta| / Vdc, Dv=|Ualpha| / Vdc+Ds, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=Dv+|Ualpha| / Vdc; If the two windings of the two-phase stepper motor and the three-phase inverter topology adopt the 24th connection method:

1. When Ualpha>=0 and Ubeta<=0 and |Ualpha|>|Ubeta|, Du=|Ualpha| / Vdc+Ds, Dv=Du-|Ubeta| / Vdc, Dw=Ds; 2. When Ualpha>=0 and Ubeta<=0 and |Ualpha|<=|Ubeta|, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du-|Ualpha | / Vdc; 3. When Ualpha>0 and Ubeta>0, Du=|Ualpha| / Vdc+Ds, Dv=Du+|Ubeta| / Vdc, Dw=Ds; 4. When Ualpha<=0 and Ubeta>=0, Du=Ds, Dv=|Ubeta| / Vdc+Ds, Dw=|Ualpha| / Vdc+Ds; 5. When Ualpha<0 and Ubeta<0, Du=|Ubeta| / Vdc+Ds, Dv=Ds, Dw=Du+|Ualpha| / Vdc.

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