Graph the 1 the simplest application give a demonstration that showed switch of suddenly Er effect feedbacks. Sensor of 3 suddenly Er is separated by 120° photo corner, spark through rotor magnet. Every 60° obtains these sensor a new digital position, produce the switch pattern that the graph shows 2 times accordingly. Accordingly, position of OK and witting rotor, resolution is 60° ; If Huo Er sensor is placed in proper place, can make signal changeover and spot of inverting of coil excitation ideal precise match. Inside this bag sth resembling a net, can use random constant or wide modulation of arteries and veins (PWM) drive signal is coil power supply, drive electric machinery runs.

 

Graph electric machinery of BLDC of 1 in-house rotor

 

Graph S1 of switch of 2 suddenly Er rotates in rotor to S3 the switch mode in a week process

 

Be in a lot of notting have to brush dc machine in, suddenly Er sensor detects directly the magnetic field of rotor magnet. Its are as a result, sensor installation is in electric machinery is in-house, expose in high temperature and vibration, lack sealed protection, gas and liquid may cause an effect to the component. In addition, install new sensor, change especially breakdown component is very painstaking work, cost is very high. Some electric machinery are added on the axis hold ring of a magnetism, will spark through this magnetism annulus suddenly Er switch, allow suddenly Er switch to be far from thereby heat component. Graph 3 those who show is give typical examples of this kind of application. The advantage of this solution is temperature lower, more facilitate the flexibility that contact and increased a design, but these advantages also have price: Increased to add the yard that install magnetism dish charge. In this kind of design, the angle sensor in mode of suddenly Er switch does not have appeal.

 

Graph 3BLDC electric machinery, take magnetic body of switch of exterior Huo Er

 

1, sensor type

 

Switch of suddenly Er effect is between two kinds of logistic condition switch, there is certain lag between these two switchpoint. People divides this kind of parts of an apparatus into two kinds big normally: Sheet pole switch, ambipolar lock is put. Take no account of here extremely complete switch and ambipolar switch.

 

Graph 4 sheet extremely switch and ambipolar switch

 

Sheet pole switch

 

Graph the 4 working principles that introduced sheet pole switch. When adscititious magnetic field crosses the job to nod BOP, parts of an apparatus outputs open. If magnetic field is released, before Brp achieves 0, switch of parts of an apparatus is answered close position. Will avoid through Bhys of a few lag transient state happens between two kinds of condition sudden switch incident.

 

Ambipolar Suo Cunqi

 

With sheet pole switch is similar, ambipolar Suo Cunqi also crosses the open after Bop in magnetic field. Nevertheless, after releasing magnetic field, although ambipolar Suo Cunqi is in 0 its position also can hold in field. After the magnetic field that inverts when polarity only passes Brp, ability can return parts of an apparatus to close position, if pursue,4 are shown. Because of be worthy of the name of these this parts of an apparatus, can effectively Suo Cunji condition.

 

1, the requirement of switch of suddenly Er effect

 

Next, let us see a few particular demands that use switch of suddenly Er effect about inverting of BLDC electric machinery:

 

Sheet pole and ambipolar

 

The task of sensor is accurate ground detects the position of rotor. Good case is, rotor position every time the sensor when as it happens changes 60° provides an inverting signal, take no account of electric machinery speed and the torque that bring to bear on, every 180° switch outputs every sensor. Graph the 5 sheet that showed a tradition extremely switch and two behavior of different ambipolar Suo Cunqi. Can see, switch can bring sheet pole to occupy sky comparing lopsidedly, and ambipolar Suo Cunqi is when Bop and Brp absolute value are equal, occupy sky comparing as it happens to be 50 ％ . Sensitivity is taller, delay is less, this is the reason that first selection is close to the switchpoint of 0mT. Accordingly, the ambipolar Suo Cunqi of tall sensitivity is the optimal choice of this application.

 

Graph the switch graph of switch of 5 different Huo Er. The lowest of defer of ambipolar Suo Cunqi of tall sensitivity, hold sky comparing balance

 

Switchpoint precision

 

Very regretful, because there has been Cheng difference in semiconductor production process, cannot create an identical sensor so. Every sensor has its individual character, and the fact proves, magnetism switchpoint is a parameter that suffers craft difference effect badly. In addition, environmental influence, shape because of 2 for example or the mechanical stress that humidity causes, also can bring about switchpoint to produce deflection during life of parts of an apparatus. To reduce these effects, switch of effect of a few suddenly Er uses behead wave principle, through clever method eliminates suddenly Er probe and the deflection that input amplifier class. This technology allows an user to appoint switchpoint inside the narrow window that has little difference only. The mechanical stress that brings from this fights the another large dominant position that function also is TLE49x6 series high.

 

Graph 7 was to show the parallel case between two when have different switchpoint difference ambipolar Suo Cunqi. Can see, at worst, if Bop and Brp as it happens are on the either end that appoints switchpoint limits, occupy sky is very more lopsided than the likelihood. Partial parts of an apparatus uses afore-mentioned behead wave principles, the difference of switchpoint is less, because this is right the effect that takes sky comparing is very little, the electric machinery in rotating to do week of process can realize a balance to send move.

 

Graph the difference with the lesser effect that 6 switchpoint difference compares for nothing to occupying can bring a balance occupy sky comparing

 

Defer

 

Magnetic field passes after 0 o’clock immediately inverting, do not answer sensor interior is handled and by defer. Suddenly Er switch of Ying Feiling is the fast signal method that is based on an input and output to have little delay only.

 

Shake

 

The repeatability of switch style is another when electric machinery inverting applies important level. With shake the metabolic extent that parameter will come to identify the switchpoint in groovy unit process of cargo bandling has how old.

 

Graph 7 stationary switchpoint and switchpoint of temperature compensation formula

 

2, the angle sensor of mode of suddenly Er switch

 

Apply in the light of what if the graph shows magnetic body of exterior Huo Er 3 times,can use, have the switch pattern that wants a sensor to be able to found switch of suddenly Er effect only, be based on the gigantic magnetoresistive that wins nobel prize (GMR) effect principle, in the IGMR technology that handles standard silicon craft to blend in its to succeed. If pursue 8 show, one is installed on electric machinery axis simple cylindrical magnetic body, use at founding to pass 2, 3, 4, 6, 7, 8, 12 mix 16 extremely right the switch mode that drive rotor place needs. Depend on automatic calibration algorithm, the angle error that is less than 1° can be obtained during temperature limits and working life (mechanical) , the switch pattern that its switch mode can offer than the most accurate suddenly Er switch normally is exacter.

 

Taller to a few requirements torsion is flowing for sexual electric machinery, use only what in brushing dc machine, use is not have in great majority piece inverting is insufficient, they need to use special winding design and comfortable the drive algorithm that match comes synchronous drive electric machinery. Electric machinery of these permanent magnetism synchronism (PMSM) needs more accurate feedback normally.

 

Graph sensor of 8 installation suddenly Er, there is a radial magnetic body on the axis