Linear motor thrust ripple feedforward suppression system based on disturbance energy observation

Abstract

The invention discloses a linear motor thrust ripple feedforward suppression system based on disturbance energy observation, and belongs to the field of linear motor control, the system calculates disturbance energy caused by thrust ripple by electromagnetic energy, load consumption energy and rotor kinetic energy variation according to an energy balance relation in a control period; calculating equivalent disturbance current according to the disturbance energy and the rotor speed; and finally, superposing the disturbance current and the collected bus current to generate a synthetic current, and injecting the synthetic current into the linear motor in a feedforward manner. According to the invention, the use of inductors, capacitors and other devices is avoided, so that the circuit design is simplified, the size, weight and cost of the system are reduced, and the stability and reliability of the system are improved. In addition, through a feedforward control method, bandwidth limitation and response lag caused by a PID controller are avoided, the dynamic response speed and the adjustment precision of the system are remarkably improved, the motor control performance is improved, and the overall efficiency of the system is improved.

Description

Technical Field

[0001] This invention belongs to the field of linear motor control, specifically, it relates to a linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation. Background Technology

[0002] Linear motors, due to their high precision and efficiency, are widely used in automated production, robotics, and precision instruments. However, during operation, thrust fluctuations often occur due to load changes and speed fluctuations, affecting equipment stability and operational accuracy. Traditional thrust fluctuation suppression methods mainly rely on current or torque control, but these methods struggle to effectively distinguish between different disturbance sources and have limited effectiveness under complex operating conditions. Therefore, a new method for suppressing thrust fluctuations is urgently needed to address these problems. To this end, this invention provides the following technical solution. Summary of the Invention

[0003] To address the issue that existing methods for suppressing thrust fluctuations in linear motors cannot accurately control disturbance energy, leading to unstable fluctuation control, this invention proposes a thrust fluctuation feedforward suppression system based on disturbance energy observation. By accurately analyzing the electromagnetic energy, load energy, and rotor kinetic energy of the motor, the remaining disturbance energy is calculated, and precise thrust fluctuation suppression is achieved through feedforward adjustment of the disturbance current.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation includes:

[0006] Sampling module, electromagnetic energy measurement module, load energy consumption monitoring module, mover kinetic energy change calculation module, disturbance energy calculation module, disturbance current estimation module, clock module, feedforward control module;

[0007] The input end of the sampling module is connected to the linear motor to collect the operating parameters of the linear motor. The output end of the sampling module is connected to the corresponding input ends of the electromagnetic energy measurement module, the load energy consumption monitoring module, the mover kinetic energy change calculation module, the disturbance current estimation module, and the feedforward control module, respectively.

[0008] The output of the clock module is connected to the electromagnetic energy measurement module, the load energy consumption monitoring module, the mover kinetic energy change calculation module, the disturbance energy calculation module, and the disturbance current estimation module to provide a synchronous clock signal.

[0009] The output of the electromagnetic energy measurement module is connected to the disturbance energy calculation module to provide the electromagnetic energy E. em ;

[0010] The output of the load energy consumption monitoring module is connected to the disturbance energy calculation module to provide the load energy consumption E. T ;

[0011] The output of the mover kinetic energy change calculation module is connected to the disturbance energy calculation module to provide the mover kinetic energy change E. M ;

[0012] The output of the disturbance energy calculation module is connected to the disturbance current estimation module to provide the disturbance energy E. S ;

[0013] The output of the disturbance current calculation module is connected to the feedforward control module to provide the disturbance current I. disturbance ;

[0014] The output of the feedforward control module is connected to the linear motor, and is used to inject the compensated synthetic current I into the linear motor. in .

[0015] As a further technical solution of the present invention, the electromagnetic energy measurement module calculates the electromagnetic energy E using the following formula. em : ;

[0016] Among them, E in E provides energy to the power source. R Energy is consumed by the resistor, E L This represents the change in the magnetic field energy stored in the stator winding.

[0017] As a further technical solution of the present invention, the power input energy E in Energy consumed by resistance E R and the change in magnetic field energy storage E L Calculated using the following formula:

[0018]

[0019] in, , The bus voltage and bus current for the current control cycle;

[0020] in the formula For the current time, This is the time corresponding to the initial moment of the current control cycle; , , This represents the phase current value flowing through the stator winding at the current moment of the current control cycle. , , This represents the phase current value flowing through the stator winding at the initial moment of the current control cycle.

[0021] As a further technical solution of the present invention, the load energy consumption monitoring module calculates the load energy consumption E using the following formula. T :

[0022]

[0023] in, , The load thrust and mover speed for the current control cycle; For the current time, This is the time corresponding to the initial moment of the current control cycle.

[0024] As a further technical solution of the present invention, the mover kinetic energy change calculation module calculates the mover kinetic energy change E using the following formula. M :

[0025]

[0026] in, For the mass of the mover, For the current control cycle and current time, the mover velocity, This represents the mover velocity at the initial moment of the current control cycle.

[0027] As a further technical solution of the present invention, the disturbance energy calculation module calculates the disturbance energy ES using the following formula: E S = E em -E T -E M .

[0028] As a further technical solution of the present invention, the disturbance current calculation module calculates the disturbance current I using the following formula. disturbance :

[0029]

[0030] in, This is the thrust fluctuation coefficient.

[0031] This application also discloses a feedforward suppression method for thrust fluctuation of a linear motor based on disturbance energy observation. This method is applied to the above-mentioned system and includes the following steps:

[0032] Within one control cycle, the bus current I of the linear motor is collected. dc Bus voltage U dc Three-phase phase current I a I b I c Motor velocity v e and load thrust F L;

[0033] Based on the collected parameters, calculate the electromagnetic energy E for the current control cycle. em Energy consumed by the load E T and the change in kinetic energy E of the mover M ;

[0034] According to the energy balance relationship, the electromagnetic energy E em Energy consumed by the load E T and the change in kinetic energy E of the mover M Calculate the disturbance energy E caused by thrust fluctuation. S ;

[0035] According to the disturbance energy E S and the velocity v of the mover e The equivalent disturbance current I is calculated. disturbance ;

[0036] The disturbance current I disturbance With the collected bus current I dc Superimposed to generate a composite current I in and the synthesized current I in Feedforward injection is given to the linear motor.

[0037] The beneficial effects of this invention are:

[0038] 1. This invention avoids the use of inductors, capacitors and other components by adopting a feedforward suppression method based on disturbance energy, thereby simplifying circuit design, reducing system size, weight and cost, and improving system stability and reliability.

[0039] 2. This invention avoids the bandwidth limitation and response lag caused by PID controllers through the feedforward control method, which significantly improves the dynamic response speed and adjustment accuracy of the system and enhances the motor control performance.

[0040] 3. This invention effectively reduces thrust fluctuations by real-time monitoring and compensation of disturbance energy, ensuring the high precision and stability of the motor, and is especially suitable for applications with large load variations.

[0041] 4. Feedforward control enables the system to respond quickly to disturbances, avoiding the lag problem in traditional feedback control, thereby effectively optimizing the suppression of thrust fluctuations.

[0042] 5. By accurately calculating and compensating for disturbance energy, this invention can effectively reduce unnecessary energy waste and improve the overall efficiency of the system. Attached Figure Description

[0043] The invention will now be further described with reference to the accompanying drawings.

[0044] Figure 1 This is a schematic diagram of the framework structure of the linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] A linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation, such as Figure 1 As shown, it includes:

[0047] Sampling module 1, Electromagnetic energy measurement module 2, Load energy consumption monitoring module 3, Mover kinetic energy change calculation module 4, Disturbance energy calculation module 5, Disturbance current estimation module 6, Clock module 7, Feedforward control module 8, Linear motor 9;

[0048] The specific connection relationship is as follows: the input end of the sampling module 1 is connected to the linear motor 9, and its output end is connected to the corresponding input ends of the electromagnetic energy measurement module 2, the load energy consumption monitoring module 3, the mover kinetic energy change calculation module 4, the disturbance current calculation module 6, and the feedforward control module 8, respectively.

[0049] The input terminal of the electromagnetic energy measurement module 2 is connected to the output terminals of the sampling module 1 and the clock module 7, and the output terminal of the electromagnetic energy measurement module 2 is connected to the disturbance energy calculation module 5.

[0050] The input terminal of the load energy consumption monitoring module 3 is connected to the output terminals of the sampling module 1 and the clock module 7, and the output terminal of the load energy consumption monitoring module 3 is connected to the disturbance energy calculation module 5.

[0051] The input terminal of the mover kinetic energy change calculation module 4 is connected to the output terminals of the sampling module 1 and the clock module 7, and the output terminal of the mover kinetic energy change calculation module 4 is connected to the disturbance energy calculation module 5.

[0052] The input terminal of the disturbance energy calculation module 5 is connected to the output terminals of the electromagnetic energy measurement module 2, the load energy consumption monitoring module 3, the mover kinetic energy change calculation module 4, and the clock module 7. The output terminal of the disturbance energy calculation module 5 is connected to the disturbance current estimation module 6.

[0053] The input terminal of the disturbance current calculation module 6 is connected to the output terminal of the disturbance energy calculation module 5 and the clock module 7, and the output terminal of the disturbance current calculation module 6 is connected to the feedforward control module 8.

[0054] The output of clock module 7 is connected to electromagnetic energy measurement module 2, load energy consumption monitoring module 3, mover kinetic energy change calculation module 4, disturbance energy calculation module 5, and disturbance current estimation module 6.

[0055] The input terminal of the feedforward control module 8 is connected to the output terminal 1 of the sampling module and the disturbance current calculation module 6, and the output terminal of the feedforward control module 8 is connected to the linear motor 9.

[0056] The input terminal of the linear motor 9 is connected to the output terminal of the feedforward control module 8, and its output terminal is connected to the sampling module 1.

[0057] in:

[0058] The sampling module 1 can be designed and implemented with reference to various existing circuits with current, voltage, speed, position detection and data transmission functions. For example, Hall-type current and voltage sensors and various motor speed sensors can be used with corresponding signal processing and analysis circuits for design and implementation.

[0059] The electromagnetic energy measurement module 2 can be implemented using a circuit capable of performing the calculations of formulas (1), (2), (3), and (4), for example, by using a digital signal processor (DSP) supplemented with corresponding peripheral circuits;

[0060] The load energy consumption calculation module 3 can be implemented by a circuit that can realize the calculation function of formula (5), for example, by using a digital signal processor (DSP) supplemented by corresponding peripheral circuits;

[0061] The kinetic energy change calculation module 4 can be implemented by a circuit that can realize the calculation function of formula (6), for example, by using a digital signal processor (DSP) supplemented by corresponding peripheral circuits;

[0062] The disturbance energy calculation module 5 can be implemented by a circuit that can realize the calculation function of formula (7), for example, by using a digital signal processor (DSP) supplemented by corresponding peripheral circuits;

[0063] The disturbance current calculation module 6 can be implemented by a circuit that can realize the calculation function of formula (8), for example, by using a digital signal processor (DSP) supplemented by corresponding peripheral circuits;

[0064] Clock circuit 7 can be designed and implemented using various existing clock signal circuits;

[0065] The feedforward control module 8 can be implemented using a circuit capable of performing the calculation function of formula (9), for example, by using a digital signal processor (DSP) supplemented with corresponding peripheral circuits;

[0066] Linear motor 9 can be any of the existing models of three-phase linear motors.

[0067] During the operation of the linear motor, within any control cycle, according to the principle of energy conservation and energy balance, the electrical energy provided by the power supply... It is mainly converted into the change in the magnetic field energy stored in the stator winding. Heat loss caused by energizing the stator winding resistance and electromagnetic energy used for mechanical consumption. .

[0068] The electromagnetic energy consumed on the mechanical side includes the mechanical energy consumed by the total load thrust. kinetic energy change of the mover and disturbance energy ; including disturbance energy This can be viewed as an additional energy loss of thrust fluctuation in the current control cycle; therefore, accurate observation of the disturbance energy can enable accurate solutions for thrust fluctuation.

[0069] Furthermore, according to the mechanical equations of a linear motor, the thrust fluctuation of the motor can be considered as the product of the thrust coefficient and the equivalent disturbance current. Therefore, accurate observation of the equivalent disturbance current can be achieved by accurately observing the disturbance energy. Injecting the observed equivalent disturbance current into the bus current through a feedforward method can effectively correct the input energy, thereby compensating for the disturbance energy and ultimately achieving an effective reduction in thrust fluctuation.

[0070] Therefore, the proposed method for feedforward suppression of thrust fluctuations in linear motors based on disturbance energy observation in this invention observes the disturbance energy in real time based on the energy balance relationship within one control cycle, and calculates the disturbance current in real time based on this energy. The disturbance current is then injected into the bus current flowing to the linear motor 9 to achieve feedforward suppression of thrust fluctuations. Its specific working principle is as follows:

[0071] First, the sampling module 1 collects motor information such as bus current, bus voltage, three-phase current, and mover speed of the linear motor 9 in real time during the current control cycle, and transmits the collected results to the electromagnetic energy calculation module 2, the load energy consumption calculation module 3, the mover kinetic energy change calculation module 4, and the feedforward control module 8. The electromagnetic energy calculation module 2 is based on the bus current, bus voltage, three-phase current collected by the sampling module 1 and the time information synchronously transmitted by the time module 7. It combines formulas (2), (3), and (4) to solve in real time the input energy, the energy consumed by the resistor, and the change in the magnetic field energy stored in the stator winding in the current control cycle. The calculated energy of each part is combined with formula (1) to solve for the electromagnetic energy of the current motor, and the electromagnetic energy obtained is transmitted to the disturbance energy calculation module 5 in real time. The load energy consumption calculation module 3 combines the load thrust and speed information transmitted by the sampling module 1 and the time information synchronously transmitted by the time module 7, and formula (5) to solve for the load energy consumption in the current control cycle in real time, and the load energy consumption obtained is transmitted to the disturbance energy calculation module 5 in real time. The mover kinetic energy change calculation module 4, combining the rotational speed information from the sampling module 1 and the time information synchronously transmitted by the time module 7, calculates the mover kinetic energy change in the current control cycle in real time using formula (6), and simultaneously transmits the calculated mover kinetic energy change for the current control cycle to the disturbance energy calculation module 5 in real time. The disturbance energy calculation module 5 calculates the electromagnetic energy from the electromagnetic energy calculation module 2, the load energy consumption calculation module 3, and the mover kinetic energy change calculation module 4. Energy consumption by the load Change in kinetic energy of the mover The energy information is combined with the synchronization time information of the clock module 7 and the disturbance energy of the current control cycle of formula (7) to solve in real time, and the calculated disturbance energy is transmitted to the disturbance current calculation module 6. The disturbance current calculation module 6 combines the disturbance energy information transmitted from the disturbance energy calculation module 5 and the time information synchronously transmitted by the time module 7, and combines formula (8) to solve the disturbance current in real time, and transmits the current to the feedforward control module 8 to compensate the current flowing to the motor. The time module 6 outputs a fixed clock signal, which is sent to the electromagnetic energy calculation module 2, the electrical load energy consumption calculation module 3, the mover kinetic energy change calculation module 4, the disturbance energy calculation module 5, and the disturbance current calculation module 6 to ensure that the clocks of these five circuits can be accurately synchronized; the feedforward control module 8 combines the bus current and disturbance current information transmitted from the sampling module 1 and the disturbance current calculation module 6 and the time information synchronously transmitted by the time module 7, and combines formula (9) to obtain the final composite current flowing to the motor, and realizes the feedforward compensation for the current.

[0072] Based on the various operating parameters of the motor obtained by the linear motor sampling module 1, combined with the motor energy balance relationship, the motor disturbance energy is observed in real time. The disturbance current is calculated based on the observation results and injected into the bus current through feedforward to effectively suppress thrust fluctuation.

[0073] Specifically:

[0074] The function of the sampling module 1 is to collect information such as current, voltage, speed and position during the operation of the motor based on current, voltage and position sensors.

[0075] The electromagnetic energy calculation module 2 functions to calculate the electromagnetic energy of the motor in real time based on the energy balance relationship within the motor; specifically, it works as follows:

[0076] Based on the current, voltage, and time information transmitted from sampling module 1 and clock module 7, and combined with the energy balance formula (1) and the energy calculation formulas (2), (3), and (4) of each part of the motor, the electromagnetic energy of the motor in the current control cycle is calculated in real time. The solution results are then passed to the disturbance energy calculation module 5.

[0077]

[0078] In the formula, Rs and Ls are the phase resistance and phase inductance, respectively;

[0079] These are the power input energy, resistor consumption energy, and stator winding magnetic field energy changes for the current control cycle, respectively.

[0080] , The bus voltage and bus current for the current control cycle;

[0081] in the formula For the current time, This is the time corresponding to the initial moment of the current control cycle;

[0082] , , This represents the phase current value flowing through the stator winding at the current moment of the current control cycle.

[0083] , , This represents the phase current value flowing through the stator winding at the initial moment of the current control cycle.

[0084] The function of load energy consumption calculation module 3 is to calculate the energy consumption of the load within the motor in real time; specifically, it is as follows:

[0085] Based on the load thrust, speed, time, and other information transmitted from sampling module 1 and clock module 7, and combined with the load energy consumption calculation formula (5), the load energy consumption of the motor in the current control cycle is calculated. The solution results are then passed to the disturbance energy calculation module 5.

[0086]

[0087] in the formula , The load thrust and mover speed for the current control cycle;

[0088] For the current time, This is the time corresponding to the initial moment of the current control cycle;

[0089] The function of the mover kinetic energy change calculation module 4 is to calculate the change in mover kinetic energy in the motor in real time; the specific method is as follows:

[0090] Based on the rotational speed information transmitted from sampling module 1 and clock module 7, and combined with the calculation equation (6) for the change in mover kinetic energy, the change in mover kinetic energy in the current control cycle is solved. The solution results are then passed to the disturbance energy calculation module 5.

[0091]

[0092] in the formula For the mass of the mover, For the current control cycle and current time, the mover velocity, This represents the mover velocity at the initial moment of the current control cycle.

[0093] The function of disturbance energy calculation module 5 is to perform real-time calculation of the disturbance energy corresponding to the thrust fluctuation within the motor; specifically, it is as follows:

[0094] The electromagnetic energy is transmitted from the electromagnetic energy calculation module 2, the load energy consumption calculation module 3, and the mover kinetic energy change calculation module 4. Energy consumption by the load Change in kinetic energy of the mover The energy information, combined with the time information of clock module 7 and the disturbance energy calculation formula (7), is used to solve for the disturbance energy consumed by the thrust fluctuation of the motor in the current control cycle. ;

[0095]

[0096] The function of the disturbance current calculation module 6 is to calculate the disturbance current in real time based on the disturbance energy calculated by the disturbance energy calculation module 5; specifically, the method is as follows:

[0097] Based on the rotational speed and time information transmitted from sampling module 1 and clock module 7, and the disturbance energy transmitted from disturbance energy calculation module 5 The disturbance current of the motor in the current control cycle is solved by combining the disturbance current calculation formula (8). ;

[0098]

[0099] In the formula For thrust fluctuation coefficient, For the current control cycle and current time, the mover velocity, For the current time, This is the time corresponding to the initial moment of the current control cycle;

[0100] The function of clock module 7 is to generate a fixed clock signal and transmit the clock signal to electromagnetic energy calculation module 2, electrical load energy consumption calculation module 3, mover kinetic energy change calculation module 4, disturbance energy calculation module 5, and disturbance current estimation module 6 to ensure that the clocks of these four circuits can be accurately synchronized.

[0101] The function of feedforward control module 8 is to perform feedforward compensation on the current bus current based on the calculated disturbance current, thereby effectively suppressing the thrust fluctuation of the current motor; specifically, the method is as follows:

[0102] According to formula (9), based on the bus current flowing out of the current power supply of the motor obtained by the sampling module, The disturbance current calculated by disturbance current estimation module 6 Superimpose the currents and make the combined currents... Flow to linear motor 9.

[0103] .

[0104] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation, characterized in that, include: Sampling module (1), electromagnetic energy measurement module (2), load energy consumption monitoring module (3), mover kinetic energy change calculation module (4), disturbance energy calculation module (5), disturbance current estimation module (6), clock module (7), feedforward control module (8); The input end of the sampling module (1) is connected to the linear motor (9) to collect the operating parameters of the linear motor (9). The output end of the sampling module (1) is connected to the corresponding input ends of the electromagnetic energy measurement module (2), the load energy consumption monitoring module (3), the mover kinetic energy change calculation module (4), the disturbance current calculation module (6), and the feedforward control module (8). The output of the clock module (7) is connected to the electromagnetic energy measurement module (2), the load energy consumption monitoring module (3), the mover kinetic energy change calculation module (4), the disturbance energy calculation module (5), and the disturbance current estimation module (6) to provide a synchronous clock signal; The output of the electromagnetic energy measurement module (2) is connected to the disturbance energy calculation module (5) to provide electromagnetic energy E. em ; The output of the load energy consumption monitoring module (3) is connected to the disturbance energy calculation module (5) to provide the load energy consumption E. T ; The output of the motioner kinetic energy change calculation module (4) is connected to the disturbance energy calculation module (5) to provide the motioner kinetic energy change E. M ; The output of the disturbance energy calculation module (5) is connected to the disturbance current calculation module (6) to provide the disturbance energy E. S ; The output of the disturbance current calculation module (6) is connected to the feedforward control module (8) to provide the disturbance current I. disturbance ; The output of the feedforward control module (8) is connected to the linear motor (9) and is used to inject a compensated synthetic current I into the linear motor (9). in .

2. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 1, characterized in that, The electromagnetic energy measurement module (2) calculates the electromagnetic energy E using the following formula. em : ; Among them, E in E provides energy to the power source. R Energy is consumed by the resistor, E L This represents the change in the magnetic field energy stored in the stator winding.

3. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 2, characterized in that, The power input energy E in Energy consumed by resistance E R and the change in magnetic field energy storage E L Calculated using the following formula: ； in, , The bus voltage and bus current for the current control cycle; in the formula For the current time, This is the time corresponding to the initial moment of the current control cycle; , , This represents the phase current value flowing through the stator winding at the current moment of the current control cycle. , , This represents the phase current value flowing through the stator winding at the initial moment of the current control cycle.

4. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 1, characterized in that, The load energy consumption monitoring module (3) calculates the load energy consumption E using the following formula. T : ； in, , The load thrust and mover speed for the current control cycle; For the current time, This is the time corresponding to the initial moment of the current control cycle.

5. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 1, characterized in that, The mover kinetic energy change calculation module (4) calculates the mover kinetic energy change E using the following formula. M : ； in, For the mass of the mover, For the current control cycle and current time, the mover velocity, This represents the mover velocity at the initial moment of the current control cycle.

6. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 1, characterized in that, The disturbance energy calculation module (5) calculates the disturbance energy ES using the following formula: E S = E em -E T -E M .

7. The linear motor thrust fluctuation feedforward suppression system based on disturbance energy observation according to claim 1, characterized in that, The disturbance current calculation module (6) calculates the disturbance current I using the following formula. disturbance : ； in, This is the thrust fluctuation coefficient.

8. A feedforward suppression method for thrust fluctuation of a linear motor based on disturbance energy observation, characterized in that, Applied to the system as described in any one of claims 1 to 7, the method includes the following steps: Within one control cycle, the bus current I of the linear motor (9) is collected. dc Bus voltage U dc Three-phase phase current I a I b I c Motor velocity v e and load thrust F L ; Based on the collected parameters, calculate the electromagnetic energy E for the current control cycle. em Energy consumed by the load E T and the change in kinetic energy E of the mover M ; According to the energy balance relationship, the electromagnetic energy E em Energy consumed by the load E T and the change in kinetic energy E of the mover M Calculate the disturbance energy E caused by thrust fluctuation. S ; According to the disturbance energy E S and the velocity v of the mover e The equivalent disturbance current I is calculated. disturbance ; The disturbance current I disturbance With the collected bus current I dc Superimposed to generate a composite current I in and the synthesized current I in Feedforward injection is given to the linear motor (9).

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