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Modelling of a Hall Effect-Based Current Sensor with an Open Core Magnetic Concentrator Ivan Yatchev 1, *, Mehmet Sen 1,2 , Iosko Balabozov 1 and Ivan Kostov 1 1 2

*

Faculty of Electrical Engineering, Tehcnical University of Sofia, 1000 Sofia, Bulgaria; [email protected] (M.S.); [email protected] (I.B.); [email protected] (I.K.) Vocational School of Technical Sciences, Uludag˘ University, 16059 Nilufer/Bursa, Turkey Correspondence: [email protected]; Tel.: +359-2-965-3873

Received: 11 February 2018; Accepted: 16 April 2018; Published: 19 April 2018

 

Abstract: The present paper deals with the modelling of a Hall effect current sensor with open core magnetic concentrator. 3D magnetic field modelling is carried out using the finite element method (FEM) and Comsol Multiphysics software. Two rectangular core constructions are considered. Different geometric parameters of the magnetic concentrator are varied and their influence on the sensor characteristic is studied, with the aim of reducing the dependence on the output signal on the distance to the conductor. Of the studied parameters, core window length leads to the most significant change in the sensor characteristic. Future work can include the optimization of the sensor construction. Keywords: current sensors; Hall effect; 3D FEM; magnetic concentrator

1. Introduction Current sensors based on the Hall effect are widely used in different applications and are the subject of increasing interest in recent years [1–4]. The output signal of sensors without a magnetic core strongly depends on the distance between the conductor and the Hall sensor, and different approaches are used for eliminating this dependence [5–7]. Where possible, constructions with magnetic cores are used [8,9]. Commercially available current measuring apparatus based on Hall effect sensors usually include a closed magnetic core with a small gap where the Hall sensor is placed. In some specific cases, though, the employment of closed cores as magnetic concentrators is not possible due to the construction of the system where the current to be measured flows. Different geometries of Hall sensors working in current mode are studied in [10]. To prove the accuracy of COMSOL models, they make comparison with results achieved from a model implemented in Verilog-A software. In [11], various schemes of magnetic biosensors that are used for the identification of a wide spectrum of biological, physical, and chemical agents are presented. By numerical simulations using the finite element method (FEM), bending-induced stress effects on ultrathin cross-shaped magnetic sensors are analyzed in [12]. One application of this type of sensors is electronic or tactile skin. In [13–15], different arrays of Hall sensors working in current mode are studied, and electronic interfaces that are used with sensors are presented. To improve the characteristics of the magnetic sensors in [16,17], optimal design solutions are studied and an optimal geometry of the Hall plate is proposed. In fixed arrangements, the sensor could be easily calibrated for any type of magnetic concentrator and also for coreless design. In nonfixed arrangements, though, especially in the case when a closed core concentrator is not practically realizable, open core magnetic concentrators could be employed, thus reducing the error in the current measurement due to an error in the distance measurement.

Sensors 2018, 18, 1260; doi:10.3390/s18041260

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Sensors 2018, 18, x  2 of 11  In the present paper, 3D FEM modelling of the magnetic field in a Hall effect-based current sensor with Sensors 2018, 18, x  an introduced magnetic concentrator of open core type is carried out with the aim of reducing 2 of 11  the In  the  present  paper,  3D  FEM  modelling  of  the  magnetic  field  in  a  Hall  effect‐based  current  dependence of the output signal on the distance between the conductor and the Hall plate. This can sensor with an introduced magnetic concentrator of open core type is carried out with the aim of  In  the  present  FEM  modelling  of sensor the  magnetic  field  in  a  Hall  effect‐based  current  give the opportunity ofpaper,  further3D  design of a current with preliminary estimated error due to the reducing the dependence of the output signal on the distance between the conductor and the Hall  sensor with an introduced magnetic concentrator of open core type is carried out with the aim of  deviation of the conductor position. plate. This can give the opportunity of further design of a current sensor with preliminary estimated 

reducing the dependence of the output signal on the distance between the conductor and the Hall  error due to the deviation of the conductor position.  plate. This can give the opportunity of further design of a current sensor with preliminary estimated  2. Studied Constructions error due to the deviation of the conductor position.  2. Studied Constructions  Two constructions of the magnetic core of the current sensor are considered: a rectangular C-core

with 2. Studied Constructions  one Two  air gap for the Hall sensor (referred to the  as construction with one air gapa or concentrator constructions  of  the  magnetic  core  of  current  sensor  are  considered:  rectangular    one  air  gap  for  the  Hall  sensor  (referred  to  as  construction  with  one  air  gap  or  with C‐core  one Two  airwith  gap), and a rectangular magnetic core with two air gaps: one for the Hall sensor constructions  of  the  magnetic  core  of  the  current  sensor  are  considered:  a  rectangular   and concentrator with one air gap), and a rectangular magnetic core with two air gaps: one for the Hall  one additional airone  gap, onthe  theHall  opposite (referred to as construction air gaps C‐core  with  air placed gap  for  sensor leg (referred  to  as  construction  with with one two air  gap  or  or sensor and one additional air gap, placed on the opposite leg (referred to as construction with two  concentrator with two air gaps). concentrator with one air gap), and a rectangular magnetic core with two air gaps: one for the Hall  air gaps or concentrator with two air gaps).  sensor and one additional air gap, placed on the opposite leg (referred to as construction with two 

2.1. Construction with One Air Gap air gaps or concentrator with two air gaps).  2.1. Construction with One Air Gap 

The construction consists of two ferromagnetic legs, which on the one end are linked with a third 2.1. Construction with One Air Gap  The  construction  consists  of  two  ferromagnetic  legs,  which  on  the  one  end  are  linked  with  a  leg with anleg  airwith  gap,an  where the where  Hall plate is placed (Figure 1).(Figure  The dimensions given ingiven  the figure are in third The  air  gap,  the  Hall  plate  is  placed  1). the  The  dimensions  in  the  construction  consists  of  two  ferromagnetic  legs,  which  on  one  end  are  linked  with  a  millimeters. The Hall plate is also included in the model (inside the air gap) and its dimensions figure leg  are with  in  millimeters.  Hall  plate  is plate  also  included  the  model  (inside  the  air given  gap)  and  its  are third  an  air  gap, The  where  the  Hall  is  placed in  (Figure  1).  The  dimensions  in  the  considered to be 0.24 × 0.24 × 0.1 mm. dimensions are considered to be 0.24 × 0.24 × 0.1 mm.  figure  are  in  millimeters.  The  Hall  plate  is  also  included  in  the  model  (inside  the  air  gap)  and  its  dimensions are considered to be 0.24 × 0.24 × 0.1 mm. 

  Figure 1. Construction with one air gap.  Figure 1. Construction with one air gap.

 

Figure 1. Construction with one air gap. 

2.2. Construction with Two Air Gaps 

2.2. Construction with Two Air Gaps

2.2. Construction with Two Air Gaps  The construction with two air gaps (Figure 2) is similar to the one in Figure 1, but a fourth leg 

The construction two air gaps (Figuregap  2) is to the one inwhere  Figure 1, Hall  but aplate  fourth with The construction with two air gaps (Figure 2) is similar to the one in Figure 1, but a fourth leg  a  second  gap with is  introduced.  The  second  is similar greater  than  the  one  the  is  leg with alocated and is large enough in order to allow passing a conductor through it.  second gap is introduced. The second gap is greater than the one where the Hall plate is located with  a  second  gap  is  introduced.  The  second  gap  is  greater  than  the  one  where  the  Hall  plate  is  and islocated and is large enough in order to allow passing a conductor through it.  large enough in order to allow passing a conductor through it.

  Figure 2. Construction with two air gaps.  Figure 2. Construction with two air gaps. 

Figure 2. Construction with two air gaps.

 

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3. FEM Modelling Sensors 2018, 18, x  3. FEM Modelling 

The finite element method is used for modelling the magnetic field of the two constructions. The 3. FEM Modelling  The  finite  element  method  is used for modelling  field  of The the  two  constructions.  Comsol Multiphysics program [18] has been employedthe  formagnetic  this purpose. AC/DC module and The  finite  element  method  is used for modelling  the  magnetic  field  of  the  two  constructions.  The  Comsol  Multiphysics program  [18]  has  been  employed  for  this  purpose.  The  AC/DC  module  Magnetic Fields and Electric Currents interfaces have been used. For computation of the Hall plate The  Comsol  Multiphysics program  [18]  has  been  employed  for  this  purpose.  The  AC/DC  module  and Magnetic Fields and Electric Currents interfaces have been used. For computation of the Hall  output voltage, the approach employed in [19] has been used. and Magnetic Fields and Electric Currents interfaces have been used. For computation of the Hall  plate output voltage, the approach employed in [19] has been used.  The finite element analysis is carried out for the 10 A value of the current in the conductor and plate output voltage, the approach employed in [19] has been used.  The finite element analysis is carried out for the 10 A value of the current in the conductor and  different parameters of the magnetic concentrator. Results for the magnetic flux density distribution The finite element analysis is carried out for the 10 A value of the current in the conductor and  different parameters of the magnetic concentrator. Results for the magnetic flux density distribution  for one variant of the two considered constructions are shown in Figures 3 and 4. different parameters of the magnetic concentrator. Results for the magnetic flux density distribution  for one variant of the two considered constructions are shown in Figures 3 and 4.  for one variant of the two considered constructions are shown in Figures 3 and 4. 

    Figure 3. Flux density distribution for the construction with one air gap. 

Figure 3. Flux density distribution for the construction with one air gap. Figure 3. Flux density distribution for the construction with one air gap. 

   

Figure 4. Flux density distribution for the construction with two air gaps.  Figure 4. Flux density distribution for the construction with two air gaps. 

Figure 4. Flux density distribution for the construction with two air gaps. Although  the  inner  dimensions  of  the  concentrator with  two gaps is  greater  than for  the  one  Although  the  inner  dimensions  of  the  concentrator with  two gaps is  greater  than for  the  one  with one gap, the flux density is greater due to introducing the leg with a second gap.  with one gap, the flux density is greater due to introducing the leg with a second gap.  Although the inner dimensions of the concentrator with two gaps is greater than for the one with In order to estimate the effect of introducing the magnetic concentrator, the dependence of the  In order to estimate the effect of introducing the magnetic concentrator, the dependence of the  one gap, the flux density is greater due to introducing the leg with a second gap. magnetic flux density in the Hall plate (volume integral average) on the distance to the conductor for  magnetic flux density in the Hall plate (volume integral average) on the distance to the conductor for  construction  magnetic  is  shown  Figure  5a.  In  Figure  5b,c,  same  In order to without  estimatea  the effectconcentrator  of introducing the in  magnetic concentrator, thethe  dependence construction  without  a  magnetic  concentrator  is  shown  in  Figure  5a.  In  Figure  5b,c,  the  same  dependence  is  shown  for  the  constructions  with  concentrators  with  one  and  two  gaps.  Both  of the magnetic flux density in the Hall plate (volume integral average) on the distance to the dependence  is  shown  for  the  constructions  with  concentrators  with (without  one  and concentrator)  two  gaps.  Both  relationships  are  close  to  a  linear  one,  while  for  the  coreless  design  the  5b,c, conductor for construction without a magnetic concentrator is shown in Figure 5a. In Figure relationships  are  close  to  a  linear  one,  while  for  the  coreless  design  (without  concentrator)  the  dependence is strongly nonlinear.  the same dependence is shown for the constructions with concentrators with one and two gaps. dependence is strongly nonlinear.  Relative values of the flux density are used in order to allow comparison between the different  Both relationships are close to a linear one, while for the coreless design (without concentrator) the Relative values of the flux density are used in order to allow comparison between the different  curves.  dependence is strongly nonlinear. curves. 

Relative values of the flux density are used in order to allow comparison between the different curves.

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  (a) 

  (b) 

  (c)  Figure  5.  Dependence  of  the  flux  density  on  the  distance  to  the  conductor  (a)  no  magnetic  Figure 5. Dependence of the flux density on the distance to the conductor (a) no magnetic concentrator; concentrator; (b) concentrator with one gap; (c) concentrator with two gaps.  (b) concentrator with one gap; (c) concentrator with two gaps.

 

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The influence of different geometric parameters has been studied for both constructions. The varied parameters are shown in Figure 6a,b. In addition to the distance between the Hall plate and 4. Results for the Influence of Different Parameters  the conductor (denoted by d), the parameters subject to variation are window length (l), window height The influence of different geometric parameters has been studied for both constructions. The  (h), and eccentricity (e) of the conductor with respect to the central line. For the case of the concentrator varied parameters are shown in Figure 6a,b. In addition to the distance between the Hall plate and  with two gaps, the size gap2by  ofd),  thethe  additional airsubject  gap is to  also varied.are  window  length  (l),  window  the  conductor  (denoted  parameters  variation  The other geometric parameters are fixed, as follows: height (h), and eccentricity (e) of the conductor with respect to the central line. For the case of the  -

concentrator with two gaps, the size gap2 of the additional air gap is also varied.  coreThe other geometric parameters are fixed, as follows:  cross section is of size 7 × 7 mm;

accommodating the Hall plate is 1.5 mm; -air gap core cross section is of size 7 × 7 mm;  diameter is 2 mm. -conductor air gap accommodating the Hall plate is 1.5 mm;  conductor diameter is 2 mm. 

(a) 

(b) 

 

 

Figure 6. Parameters subject to variation for the two constructions: (a) construction with one air gap; 

Figure 6. Parameters subject to variation for the two constructions: (a) construction with one air gap; (b) construction with two air gaps.  (b) construction with two air gaps.

4.1. Construction with One Air Gap 

4.1. Construction with One Air Gap

Three parameters have been varied for the construction with one air gap: the length l and height 

h of the window and deflection of the conductor from the central symmetry line e.  Three parameters have been varied for the construction with one air gap: the length l and height The dependence of the magnetic flux density B in the Hall plate (volume integral average) on  h of the window and deflection of the conductor from the central symmetry line e. the distance between the conductor and the Hall plate for different parameter values are shown in  The dependence of the magnetic flux density B in the Hall plate (volume integral average) on Figures 7–9. For better comparison of the different characteristics, the flux density in the Hall plate is  the distance between the conductor and the Hall plate for different parameter values are shown in presented in relative units with respect to its maximal value Bmax, which is obtained in the plate at  Figures 7–9. For better comparison of the different characteristics, the flux density in the Hall plate is the minimal considered distance (10 mm) between the conductor and the Hall plate.  presentedCore  in relative units with respect to its maximal value Bmax, which is obtained in the plate at the window  length  has  a  significant  influence  on  the  flux  density–distance  relationship,  minimal considered distance (10 mm) between the conductor and the Hall plate. leading to about 30% difference between the flux density for the first and the last value of the length  Core window length at the largest distance. has a significant influence on the flux density–distance relationship, leading to about 30% difference flux density for the first and the conductor  last value from  of the length at the Variations  of between the  core  the window  height  and  deflection  of  the  the  central  symmetry  largest distance.line  do  not  lead  to  significant  change  in  the  characteristics  (about  4–6%  at  the  largest  distance).  of the core window height and deflection of the conductor from the central symmetry Variations line do not lead to significant change in the characteristics (about 4–6% at the largest distance).

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   Figure 7. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 7. Dependence of the flux density on the distance to the conductor for the concentrator with Figure 7. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 7. Dependence of the flux density on the distance to the conductor for the concentrator with  one gap and different window lengths l.  one gap and different window lengths l. one gap and different window lengths l.  one gap and different window lengths l. 

   Figure 8. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 8. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 8. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 8. Dependence of the flux density on the distance to the conductor for the concentrator with one gap and different window heights h.  one gap and different window heights h.  one gap and different window heights h. one gap and different window heights h. 

   

Figure 9. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 9. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 9. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 9. Dependence of the flux density on the distance to the conductor for the concentrator with one gap and different conductor deflections in the transversal direction e.  one gap and different conductor deflections in the transversal direction e.  one gap and different conductor deflections in the transversal direction e.  one gap and different conductor deflections in the transversal direction e.    

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4.2. Construction with Two Air Gaps 4.2. Construction with Two Air Gaps  4.2. Construction with Two Air Gaps Four parameters have been varied for the construction with two air gaps. In addition to the Four parameters parameters have been varied varied for for the the construction construction with with two two air air gaps. In addition addition to to the the  Four In parameters varied for thehave  casebeen of one air gap, the value of the additional airgaps.  gap is also varied. parameters varied for the case of one air gap, the value of the additional air gap is also varied.    parameters varied for of thethe case of one air the value of the additional air gap also varied.and Hall The dependences relative fluxgap, density on the distance between theis conductor The dependences of the relative flux density on the distance between the conductor and Hall  The dependences of the relative flux density on the distance between the conductor and Hall plate for different parameters of this construction are shown in Figures 10–13. plate for different parameters of this construction are shown in Figures 10–13.  plate for different parameters of this construction are shown in Figures 10–13. For this construction, both sizes of the core window (length and height) influence the sensor For this this construction, construction, both both sizes sizes of of the the core  window (length (length and and height) influence  the sensor sensor  For coresecond window performance. Regarding the influence of the air gap, as it height) can be influence expected,the the lowest performance.  Regarding  the  influence  of  the  second  air  gap,  as  it  can  be  expected,  the  lowest  performance. Regarding the influence of the second air gap, as it can be expected, the lowest dependence on the distance features the construction with the smallest value of the second air gap. dependence on the distance features the construction with the smallest value of the second air gap.  dependence on the distance features the construction with the smallest value of the second air gap. ForFor comparison, in Figure 13, the dependence of the construction with the closed core is also given.  comparison, in Figure 13, the dependence of the construction with the closed core is also given. For comparison, in Figure 13, the dependence of the construction with the closed core is also given. ForFor this construction, the window length and height have more influence on the dependence on  this construction, the window length and height have more influence on the dependence on For this construction, the window length and height have more influence on the dependence on thethe conductor position, leading to changes of 13% and 10%, respectively. The variation of the other  conductor position, leading to changes of 13% and 10%, respectively. The variation of the other the conductor position, leading to changes of 13% and 10%, respectively. The variation of the other twotwo studied parameters results in less than 5% change in the characteristic.  studied parameters results in less than 5% change in the characteristic. two studied parameters results in less than 5% change in the characteristic. AllAll thethe obtained characteristics with open corecore magnetic concentrators, though, feature an almost All  the  obtained  characteristics  with  open  core  magnetic  concentrators,  though,  feature  an  obtained characteristics with open magnetic concentrators, though, feature an linear dependence on the distance between the conductor and the Hall plate. almost linear dependence on the distance between the conductor and the Hall plate.    almost linear dependence on the distance between the conductor and the Hall plate.

  Figure 10. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure 10.10. Dependence distanceto tothe theconductor conductorfor forthe theconcentrator concentrator with Figure Dependenceofofthe theflux fluxdensity density on on the the distance with two gaps and different window lengths l.  two gaps and different window lengths l. two gaps and different window lengths l.

 

Figure 11. Dependence of the flux density on the distance to the conductor for the concentrator with  Figure Dependenceofofthe theflux fluxdensity density on on the the distance with Figure 11.11. Dependence distanceto tothe theconductor conductorfor forthe theconcentrator concentrator with two gaps and different window heights h.  two gaps and different window heights h. two gaps and different window heights h.

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Figure 12. Dependence Dependence of of the the flux flux density density on on the the distance distance to to the the conductor conductor for for the the concentrator concentrator with with Figure 12. Figure 12. Dependence of the flux density on the distance to the conductor for the concentrator with  two gaps and different conductor deflections in the transversal direction e. two gaps and different conductor deflections in the transversal direction e. two gaps and different conductor deflections in the transversal direction e. 

  Figure 13. Dependence Dependence of of the the flux flux density density on on the the distance distance to to the the conductor conductor for for the the concentrator concentrator with with Figure 13. Figure 13. Dependence of the flux density on the distance to the conductor for the concentrator with  two gaps and different values of the second air gap (gap2). two gaps and different values of the second air gap (gap2). two gaps and different values of the second air gap (gap2). 

4.3. Results for Different Values of the Measured Current 4.3. Results for Different Values of the Measured Current  4.3. Results for Different Values of the Measured Current For estimation of the influence of the value of the current on the output voltage signal from the For estimation of the influence of the value of the current on the output voltage signal from the  For estimation of the influence of the value of the current on the output voltage signal from the Hall plate, the output signal has been computed for different values of the current, varying the latter Hall plate, the output signal has been computed for different values of the current, varying the latter  Hall plate, the output signal has been computed for different values of the current, varying the latter from 10 to 40 A. computations have been out using the approach in [19] from 1010  A.  The The  computations  have carried been  carried carried  out  the  in approach  in  construction [19]  for for  the the  from toto  40 40  A. The computations have been out using theusing  approach [19] for the construction with two air gaps and value of the second gap of 5 mm. construction with two air gaps and value of the second gap of 5 mm.    with two air gaps and value of the second gap of 5 mm. In Figure 14, the dependence of the Hall plate output voltage Vhall on the current I for different In Figure 14, the dependence of the Hall plate output voltage Vhall on the current I for different  In Figure 14, the dependence of the Hall plate output voltage Vhall on the current I for different distances to the conductor is given. In Figure 15, the same family of curves has been presented as the distances to the conductor is given. In Figure 15, the same family of curves has been presented as the  distances to the conductor is given. In Figure 15, the same family of curves has been presented as the dependence of the Hall plate output voltage on the distance to the conductor for different currents. dependence of the Hall plate output voltage on the distance to the conductor for different currents.  dependence of the Hall plate output voltage on the distance to the conductor for different currents. The obtained results give the possibility of the difference in the The obtained obtained results results  give  possibility  of  estimating estimating  the  maximal maximal  difference  the  output output  The give thethe  possibility of estimating the maximal difference in the in  output signal signal when varying the distance from the conductor to the Hall plate from 10 to 40 mm. This signal varying when  varying  the  distance  the  conductor  to  the  Hall  plate  from  10  to This 40  mm.  This  when the distance from thefrom  conductor to the Hall plate from 10 to 40 mm. maximal maximal difference is less than 24% for all currents. maximal difference is less than 24% for all currents.  difference is less than 24% for all currents. The linearity of the obtained dependencies could be used as an objective function in a future The linearity of the obtained dependencies could be used as an objective function in a future  The linearity of the obtained dependencies could be used as an objective function in a future optimization. Having the best linear fit of the characteristics (Hall plate output voltage relative to the optimization. Having the best linear fit of the characteristics (Hall plate output voltage relative to the  optimization. Having the best linear fit of the characteristics (Hall plate output voltage relative to distance of the distance  of  the  conductor conductor  to to  the the  Hall Hall  plate), plate),  it it  will will  be be  possible possible  to to  design design  aa  current current  sensor sensor  with with  preliminary estimated current error with respect to the distance error. preliminary estimated current error with respect to the distance error. 

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the distance of the conductor to the Hall plate), it will be possible to design a current sensor with preliminary estimated current error with respect to the distance error. Sensors 2018, 18, x  9 of 11  Sensors 2018, 18, x 

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    Figure 14. Dependence  the  plate  voltage  Vhall  on the  current  for different distances  to  the  Figure 14. Dependenceof  theHall  Hall plate voltage Vhall on the current for different distances to Figure 14. Dependence  of ofthe  Hall  plate  voltage  Vhall  on the  current  for different distances  to  the  conductor.  the conductor. conductor. 

    Figure  15.  Dependence  of  the  Hall  plate  voltage  Vhall  on  the  distance  to  the  conductor  for  four  Figure  15.  Dependence  four  Figure 15. Dependence of  of the  the Hall  Hall plate  plate voltage  voltage Vhall  Vhall on  on the  the distance  distance to  to the  the conductor  conductor for  for four different currents.  different currents.  different currents.

5. Conclusions  5. Conclusions  5. Conclusions Computer  models  for  the  constructions  of  Hall  effect‐based  current  sensors  with  additional  Computer  models  for  the  constructions  of  Hall  effect‐based  current  sensors  with  additional  models concentrators  for the constructions of Hall effect-based current of  sensors with additional open open Computer core  magnetic  are  created.  The  employment  an  open  core  magnetic  open  core  magnetic  concentrators  are  created.  The  employment  of  an  open  core  magnetic  core magnetic concentrators are created. The employment of an open core magnetic concentrator leads concentrator leads to an almost linear dependence of the output signal on the distance between the  concentrator leads to an almost linear dependence of the output signal on the distance between the  to an almost linear dependence of the output signal on the distance between the conductor and the conductor and the Hall plate. The influence of changing different geometric concentrator parameters  conductor and the Hall plate. The influence of changing different geometric concentrator parameters  Hall plate. The influence of changingof  different geometric concentrator estimated for two is  estimated  for  two  constructions  the  magnetic  concentrator  of parameters rectangular isshape,  showing  a  is  estimated  for  two  constructions  of  the  magnetic  concentrator  of  rectangular  shape,  showing  a  constructions of the magneticof concentrator oflength  rectangular shape, showing a more significant influence more  significant  influence  the  window  and  height.  The  dependence  of  the  Hall  plate  more  significant  influence  of  the  window  length  and  height.  The  dependence  of  the  Hall  plate  of the window length and height. The dependence of the Hall plate output voltage on the distance to output voltage on the distance to the conductor has been obtained for different values of the current,  output voltage on the distance to the conductor has been obtained for different values of the current,  the conductor hasof been obtained for values ofThis  the current, and estimation of its linearity can and  estimation  its  linearity  can different be  performed.  linearity  can  be  the  subject  of  further  and  estimation  of  its  linearity  can  be  performed.  This  linearity  can  be  the  subject  of  further  be performed. This linearity can be the subject of further optimization with the aim of the design of optimization with the aim of the design of a current sensor with an open core magnetic concentrator  optimization with the aim of the design of a current sensor with an open core magnetic concentrator  a current sensor with an open core magnetic concentrator for nonfixed arrangements. for nonfixed arrangements.  for nonfixed arrangements.  Acknowledgments:  Financial  support  Uludag  University  for  covering  costs  of  open  access  Acknowledgments: Financial support from from  Uludag University for covering costs of open access publishing is Acknowledgments:  Financial  support  from  Uludag  University  for  covering  costs  of  open  access  greatly acknowledged. publishing is greatly acknowledged.    publishing is greatly acknowledged.    Author  Contributions:    I.Y.,  M.S.  and  I.B.  performed  the  computer  modelling,  I.Y.,  M.S.  and  I.K.  Author  Contributions:    I.Y.,  M.S.  and  I.B.  performed  the  computer  modelling,  I.Y.,  M.S.  and  I.K.  analyzed the results, I.Y. wrote the paper.    analyzed the results, I.Y. wrote the paper.   

Conflicts of Interest: The authors declare no conflict of interest.  Conflicts of Interest: The authors declare no conflict of interest. 

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Author Contributions: I.Y., M.S. and I.B. performed the computer modelling, I.Y., M.S. and I.K. analyzed the results, I.Y. wrote the paper. Conflicts of Interest: The authors declare no conflict of interest.

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