AT509574B1 - FOUR QUADRANTS CONTROLLERS WITH INHERENT FINISHING - Google Patents

Description

Austrian Patent Office AT509 574B1 2012-03-15

[0001] Four-quadrant actuators with inherent smoothing (filed Aug. 10, 2009) [0002] The invention relates to four-quadrant actuators for controlling permanently excited DC machines and other loads, constructed from two bidirectional half-bridges (HBi, HB2), each having a positive (ΗΗHH2) , middle (HM !, HM2) and a negative (HL ^ HL2) terminal, each consisting of a first active switch (Sn or S12), connected in series with a respective second active switch (S2i or S22), wherein an antiparallel diode (Dn, D12, D21, D22) is connected to each active switch (Sn, Si2, S2i, S22), furthermore consisting of two coils (Li, L2) or four coils (Ln, L21, L12, L22), of two capacitors (Cn C2) or four capacitors (Cn, C2i, C12, C22), a first positive (E ^ and a second negative (E2) input terminal for connection of a unipolar voltage source (Ui) and a first (A ^ and second (A2) Output terminal for connecting the La st.

The prior art can be found in the patent literature WO 2002089308 A1 (AFL GERMANY ELECTRONICS GMBH). The classic half bridge is treated here. At the load (machine) a pulse-shaped voltage is applied, in addition, the voltage at the load can not be greater than the operating voltage. A comparison with the circuits treated in the subject patent shows the difference. By virtue of the smoothing inherent in the circuit, there is no pulse voltage on the machine but a smoothed one. This improves the electromagnetic compatibility and leads to reduced insulation load of the machine and the commutator. In one of the presented circuits, in addition, the voltage on the machine can be raised above the operating voltage.

The most commonly used four-quadrant drive stage is a full bridge (Figure 2), also called the H-bridge, consisting of two half-bridges (Figure 1). The load is connected between the midpoints of the half bridges. Consider, e.g. a motor drive, it follows, neglecting the losses for the speed of a permanent-magnet DC machine, at the supply voltage Ui, the voltage constant of the permanent-magnet motor cE and the duty ratio d to n = --d-ul. These frequently used shells

Cf tion but also has some disadvantages or limitations. There is a pulse-shaped voltage at the load (machine). This leads to parasitic capacitances to displacement currents through the housing and bearings. Furthermore, it comes with longer leads to the load to voltage overshoots on the machine winding and unwanted emissions. In addition, the pulse-shaped voltage leads to a greater load of winding insulation compared to DC voltages or slowly varying voltages. Especially at low operating voltages is added that the voltage at the load can not be raised above the operating voltage. In addition, the current drawn from the source is pulsed. Filters can be used against the pulse-shaped voltage or the pulse-shaped current and against the too low voltage with an upstream step-up converter. However, the four-quadrant drive circuits presented here basically overcome the stated disadvantages and limitations.

The circuits are constructed of two half-bridges. These each consist of two active (S ^ S2) and two passive (D ^ D2) switches. The two active switches (S ^ S2) are connected in series and each antiparallel bridged by a diode (D ^ D2). The positive terminal of the first active switch (S1) simultaneously forms the positive terminal (HH) of the half-bridge (HB). The connection between the negative terminal of the first active switch (SO with the positive terminal of the second active switch (S2) forms the middle terminal (HM) of the half-bridge (HB) and the negative terminal of the second active switch (S2) forms the negative terminal (HL) of the half-bridge (HB).

It should be noted here that, in principle, any two-pole load for which a two- or four-quadrant operation is advantageous can be used as the load except for a permanently excited DC machine. Austrian Patent Office AT509 574B1 2012-03-15 In the first circuit variant (Fig. 3), a coil is now connected between the first input terminal and the middle terminal of the two half-bridges. The two negative terminals of the half bridges are connected together with the second input terminal. Between the positive and the negative terminal of each half-bridge a capacitor is switched. This can also be designed as a polarized capacitor. The first output terminal is connected to the positive terminal of the first half-bridge and the second output terminal is connected to the positive terminal of the second half-bridge.

In the second circuit variant (FIG. 4), a coil is now connected in each case between the first input terminal and the positive terminal of the two half bridges. Between the positive and the negative terminal of each half-bridge a capacitor is switched. Furthermore, a capacitor is connected between the middle terminal of each half-bridge and the second input terminal of the circuit. All capacitors can be designed as poled types. A coil is connected between the second input terminal and the negative terminals of the half bridges. These can be linked together. The middle terminals of the half bridges are connected to the output terminals of the circuit.

For the control of the converter several concepts are available. If one controls the half-bridges in push-pull operation, then the coils of the circuit are in continuous operation (non-latching operation). To keep the current load of the input source low, it may be useful to offset the drive signals of the two half-bridges to each other.

To perform the source low impedance and to avoid the effects of the inductance of the supply line, a capacitor should be connected in parallel with the input terminals.

The task to realize a four-quadrant with inherent smoothing is inventively achieved in that between the first input terminal (Ei) and the middle terminals (HMi, HM2) of the two half-bridges (HBi, HB2) each have a coil (L_i, L2) is connected and the two negative terminals (HU, HL2) of the half-bridges (HBi, HB2) are connected together with the second input terminal (E2) and between the positive (HHi, HH2) and the negative (HLi, HL2) terminal of each half-bridge ( HB !, HB2), a capacitor (Ci, C2) is connected and the first output terminal (Ai) to the positive terminal (HHi) of the first half-bridge (HBi) and the second output terminal (A2) to the positive terminal (HH2) of the second Half bridge (HB2) is connected, or that between the first (egg) input terminal and the positive terminals (HHi, HH2) of the two half-bridges (HB !, HB2) each have a coil (Lu, Li2) is connected and that between the positive ( HHi or HH2) and the negative terminal (HLi or HL2) of each half-bridge (HBi or HB2) a capacitor (Cu or Ci2) is connected and between the middle (HMi or HM2) terminal of each half-bridge (HB! or HB2) and the second (E2) input terminal of the circuit, a capacitor (C2i or C22) is connected and between the second input terminal (E2) and the negative terminals (HLi or HL2) of the half-bridges (HBi, HB2) one each Coil (L2i, L22) is connected and the middle terminal (HMi) of the first half-bridge (HBi) to the first output terminal (Ai) and the middle terminal (HM2) of the second half-bridge (HB2) to the second output terminal (A2) is connected ,

The coils of the circuit can also be coupled in various ways. As a result, a further improvement of the filter effect can be achieved.

The figures illustrate a half bridge (Figure 1), a full bridge (Figure 2) and the two variants of the four quadrant actuator described herein with inherent smoothing (Figures 3 and 4). In Fig. 2, the active switch is exemplified as a self-locking n-channel MOSFET. Of course, any active switch can be used. It should also be noted that the half bridges are also available as finished assemblies (modules). 2.5

Claims (6)

Austrian Patent Office AT509 574B1 2012-03-15 1. Vierquadrantensteller for controlling permanently excited DC machines and other loads, constructed from two bidirectional half-bridges (HBi, HB2), each with a positive (HHi, HH2), middle (HMi, HM2) and a negative (HLi, HL2) terminal, each consisting of a first active switch (Sn or S12), connected in series with a respective second active switch (S21 or S22), wherein to each active switch (S11, Si2, S2i , S22) an antiparallel diode (Du, D12, Du, D12) is connected, further consisting of two coils (Ln L2), two capacitors (Ci, C2), a first positive (Ei) and a second negative (E2) input terminal for connecting a unipolar voltage source (Ui) and a first (Ai) and second (A2) output terminal for connection of the load (M), characterized in that between the first input terminal (Ei) and the middle terminals (HM !, HM2) of the two Halbbrüc ken (HB !, HB2) in each case a coil (Li, L2) is connected and the two negative terminals (HLi, HL2) of the half-bridges (HBi, HB2) with the second input terminal (E2) are connected together and between the positive (HHi , HH2) and the negative (HLi, HL2) terminal of each half-bridge (HBi, HB2), a capacitor (Ci, C2) is connected and the first output terminal (Ai) to the positive terminal (HHi) of the first half-bridge (HBi) and the second output terminal (A2) is connected to the positive terminal (HH2) of the second half-bridge (HB2). 2. four-quadrant controller for controlling permanently excited DC machines and other loads, constructed from two bidirectional half-bridges (HBi, HB2), each having a positive (HHi, HH2), a middle (HMi, HM2) and a negative (HLi, HL2) connection, each consisting of a first active switch (Sn, or Si2), connected in series with in each case a second active switch (S2i, or S22), wherein for each active switch (Sn, Si2, S2i, S22) an antiparallel diode ( Du, Di2, Du, Di2), further consisting of four coils (Ln, L2i, Li2, L22), four capacitors (Cn, C2i, Ci2, C22), a first positive (Ei) and a second negative (E2 ) Input terminal for connecting a unipolar voltage source (Ui) and a first (Ai) and second (A2) output terminal for connection of the load, characterized in that between the first (Ei) input terminal and the positive terminals (HHi, HH2) of the two half-bridges ( HBi, HB2) in each case one coil (Lu, U2) is connected and that between the positive (HHi or HH2) and the negative terminal (HLi or HL2) of each half-bridge (HBi or HB2), a capacitor (Cu or Ci2) is connected and between the middle (HMi or HM2 ) Terminal of each half-bridge (HBi or HB2) and the second (E2) input terminal of the circuit a capacitor (C2i or C22) is connected and between the second input terminal (E2) and the negative terminals (HLi or HL2) of the half-bridges ( HBi, HB2) in each case a coil (L2i, L22) is connected and the middle terminal (HMi) of the first half-bridge (HB!) With the first output terminal (A ^ and the middle terminal (HM2) of the second half-bridge (HB2) with the second output terminal (A2) is connected. 3. Vierquadrantensteller according to claim 2, characterized in that the coil (Lu) between the first input terminal (Ei) and the positive terminal (HHi) of the first half-bridge (HB!) With the coil (L21) between the second input terminal (E2) and the negative terminal (HLi) of the first half bridges (HBi) is coupled together and further the coil (Li2) between the first input terminal (Ei) and the positive terminal (HH2) of the second half bridge (HB2) with the coil (L22) between the second input terminal (E2) and the negative terminal (HL2) of the second half-bridges (HB2) is coupled together. 4. Vierquadrantensteller according to claim 2, characterized in that the coils (L2i, L22) between the second input terminal (E2) and the negative terminals (HLi or HL2) of the half-bridges (HBi or HB2) are coupled together. 3/5 Austrian Patent Office AT509 574B1 2012-03-15 5. Four-quadrant controller according to one of claims 1 to 4, characterized in that the half-bridges are operated in push-pull and driven in phase with each other. 6. Four-quadrant actuator according to one of claims 1 to 5, characterized in that between the first (Ei) and second (E2) input terminal another capacitor is connected. 1 sheet of drawings 4/5